Saturday, December 27, 2008

Soldano 44

My bandmate in Roadhouse Joe, guitarist Scott Mishoe, bought a very cool little amp from Soldano sold only through Blues City Music near Memphis. The Soldano 44 is a 50-watt 1x12 amp, driven by two Sovtek 5881 power tubes and five (!) 12AX7 preamp tubes. Needless to say, this is one high-gain puppy.

He opted for the matching extension cab, so this rig is a neat little stack. The tone is Marshall-ish to my ear, and very musical and colorful. The dynamics are exceptional.

I was helping Scott dial the amp in when I recorded these short clips:

Soldano 44 Rock. Scott is feeling his inner head-banger.

Soldano 44 Blues. Scott noodles around with some blues licks, trying various guitar settings. Nice tone; no effects.

Soldano 44 Harp. I plugged in without changing any settings, and the result was nasty. I do not mean that in a good way. Great guitar amps don’t always make good harp amps.

Wednesday, December 17, 2008

The Voodoo 5F2H Amp at Work


Here is a short clip of the 5F2H amp at band practice. The drummer took a break and the guitarist started jamming on some slow blues. You can hear me asking what key.

Click here for the sound clip.

In this configuration the 5F2H amp has the Mojotone speaker and a TAD 6L6WGC STR power tube. It's not mic'ed and I'm not using any effects. The recording was made with the Zoom H4 field recorder in the corner of the room.

Monday, December 8, 2008

Joe's Blues Blog



My buddy Joe Lempkowski from the East Bay has spiffed up his blues blog and posted some great new stuff. In this post Joe does a killer set at the Redwood City Blues Jam at the Little Fox Theater, showing off his good chops on a Sonny Jr. Cruncher amp. His regular gig rig is a HarpGear Double Trouble amp. Joe also posts a review of a Skip Simmons-modded Masco MA-17 harp amp. Go check it out.

Monday, November 24, 2008

Review: Fender Pro Junior Project Harp Amp


I’ve played out with the Fender Pro Junior project harp amp a few times now. Here are my impressions:

-It’s LOUD! This little sucker will crank, handling most gigging situations with ease. It is sometimes too loud, and I have to lower the volume. But even on 3 or 4 the amp gets some crunch on tightly cupped bends or duo-tone chords. However, it does its best work above 8 (out of 12) on the volume.

-It cuts through the mix. This amp has the character of a Champ. It is “barky” and hot. This ain’t the fat rolling tone that oozes from big saggy amps; its more horn-like, slightly muted. I have a Weber Beam blocker on the speaker to avoid beaminess, which seems to work well.

-Feedback has not been a big problem. For whatever reason, I’m usually able to crank it and just play; not wandering all over the stage looking for that one perfect spot where the feedback demons disappear.

-I get lots of compliments on the tone, not just from the audience but from blues players. They’re pretty impressed with this little amp. I think it shines for blues rock or boogie.

The
Fender Pro Junior project amp has become my backup rig. I take it whenever I play, just in case. It is small, light, and reliable. I’ve jammed on it for hours with no ill effects. It sings with just a touch of delay.

Cool little amp. I think I’ll keep it.

UPDATE 12/02/08:
Here is a short clip of the Pro Junior getting thrashed at a blues jam.

Wednesday, November 19, 2008

Review: Harmonica for Dummies

Winslow Yerxa, a player well-known on the Harp-L online board, has authored a very good primer on all things harmonica. In the tightly controlled style of the For Dummies genre, this book is a great reference. The writing is concise and clean and the indexes are easy to follow. It is an encyclopedia, not something you need to read from cover to cover. Pick the topics that interest you and save the rest for another day.

The topic that interests me, of course, is harp amps. Yerxa gives rather scanty coverage to this fascinating and important topic that bears so much on tone. To his credit, he steered away from moldy old canards spouted by crusty harp curmudgeons: 1) You must never consider amping your harp until after you have achieved acoustic tone perfection, and 2) Tone comes only from the player, never from the amp. Instead, Yerxa presents the thinnest of harp amp gruel, as if tip-toeing past the topic while not wishing to offend.

The only reference I could find to tubes in his entire section on amps was this, in a paragraph about dealing with feedback:

"Swap the tubes, which are internal plug-in parts that look like tiny science fiction light bulbs"

Good grief!

While Yerxa named a list of microphones that might be suitable for harp (Shure SM57, SM58, 545, and Green Bullet; EV RE10; Audix Fireball; Astatic JT-30; Hohner Blues Blaster) he was mysteriously unable to name a single specific amplifier that might suit harp playing. Why could he not even utter the word “Champ?”

At the end of the chapter on amps Yerxa advised the reader to consult online harmonica sites for more information. If you have arrived here in search of actual useful information about harp amps, you’ve come to the right place.

First, if you are new at this and you know you are interested in a blues or rock tone, get yourself a small tube amp, such as a Fender Champ from the 1970s or a Kalamazoo Model 2. Both are readily available on eBay and elsewhere, and they are inexpensive at $200 to $300.

An even better choice might be a new Epiphone Valve Junior Half Stack, at about $250. All these amps sound great for blues harp with no modifications. Get your microphone (Yerxa’s list is good) and PLAY! You’ll be a harp amp “expert” in no time.

If, on the other hand, you are interested in the cleaner sound associated with country music (or jazz, folk, gospel, bluegrass, Irish, etc), I suggest you don’t buy an amp at all. Instead, buy a small PA system. Start with a 200-watt, eight channel powered mixer and add speakers, stands, and monitors. Shop Craigslist for deals on used products from Peavey, Behringer, Samson, Mackie, Yamaha, etc. Experiment with effects and pedals. Work on your mic technique. As a big added bonus, you’ll be a much more attractive candidate when you start looking around for bands to join if you own a PA system.

There. You now have good advice on how to get started amping your harp. You will inevitably learn more as you go along and make changes. But every blues player needs a small tube amp, and every country/bluegrass/jazz player needs a basic PA.

Harmonica for Dummies by Winslow Yerxa is excellent. I love the sections about harp customizing, positions, overblows and overbends. I’ll refer back to the book often. But the harp newbies who buy the book in search of advice about amps (a very hot topic among new players) will find little useful specific information beyond the suggestion to look elsewhere.

I give this book a IV on the I – IV – V scale of blues harp excellence. Like a small tube amp, every harp player should own this book.



UPDATE: Winslow Yerxa sent a very nice response to this review:

As to your criticisms of the amp chapter in the full review on your blog, guilty as charged. To the "espresso fiend" end of the gear spectrum, the chapter may seem like cold decaf, but to the general reader who may or may not be interested in amplified blues playing, I hope that it will serve as a decent general introduction to the subject.

Some background: I had to fight to include a chapter on such an "advanced" subject, and then had to make huge cuts to fit page counts. Also, I was writing for people who had potentially never picked up a harmonica or seen a vacuum tube or even knew what an amplifier was (part of the Dummies philosophy - assume nothing about what your reader might know). Hence the "tiny science fiction light bulbs" description of tubes (remember, there are people who have grown up in a solid-state microprocessor world who may have no idea what a tube is). Also, I was not writing with a main focus on amplified blues playing, but rather just on the general subject of playing with some kind of amplification, with a nod in the general direction of blues. It was these circumstances that informed the general and conservative nature of the advice in that chapter.

Many thanks to Winslow for his fine book and his willingness to respond. It is much appreciated.

Monday, November 17, 2008

Kenny Blue Ray

I bought a pair of used speakers from Kenny Blue Ray, a premier blues guitar guy from the Bay Area. The speakers are 10A125-O Webers (lightly gigged), which I will use in my 2x10 cab with my Masco amp. I have the same speaker in my project Champ, and the tone is outstanding.

Kenny Blue Ray played and/or recorded with Little Charlie & the Nightcats, SRV, William Clarke, James Cotton, Mark Hummel, Gary Smith, Kim Wilson, Paul Delay and others. These speakers are gonna have some serious mojo.

Thanks, Kenny!

Friday, October 24, 2008

Weber 5F2H Harp Amp


Here is my most recent acquisition: A Weber 5F2H Harp Amp. This amp is sold as a kit by Ted Weber, but this example is already professionally built with a few interesting upgrades.

The 5F2H is basically a clone of a 1950s Fender Tweed Princeton amp that has been hot-rodded for harp. Instead of 5 watts from a single 6V6 power tube, the 5F2H produces 15 watts from a KT66 tube (one of the 6L6 family) and a bigger output transformer. It is a single-ended Class A tone monster.



This amp differs from the stock Weber kit in several ways. The input tube is a beautiful NOS RCA Blackplate 5751, my all-time favorite preamp tube for harp. The rectifier is a solid state Weber Copper Cap WZ34 in place of the glass tube. These Copper Caps have all the sag and tone of the tube, but are much quieter and will last the life of the amp.

The biggest upgrade is the cabinet, a 5E3 (Fender Tweed Deluxe) with a 12-inch speaker. The Pro Junior is pictured next to the 5F2H for size reference. Check out that snakeskin tolex. I’m not sure I’m cool enough for that…



When I got the amp it had a nice old Mojotone MP12R alnico speaker, which is a very good guitar speaker; a knockoff of the Jensen vintage alnicos. However, I don’t care for the sound of the Jensen alnico as the only speaker in a harp amp. They can sound great combined with other speakers in a multi-speaker cab, but by themselves they sound too bright and harsh for my tastes. I’ve removed the speaker (it is for sale) and I’ve ordered a Weber 12F125-O with the H dustcap.

The amp cab, speaker, and chassis had a few alignment issues when I got it (the KT66 tube touched the speaker magnet, for example) but the switch to the ceramic speaker will help, and I’ll tweak things when I re-assemble the amp. Also, I need to devise a way to brace the chassis from the bottom or sides. It is too heavy to be held in place only by two bolts in the top of the amp.

I didn’t play it much before tearing it apart, but I did do an A-B comparison with my project Fender Pro Junior amp. They seemed to have about the same volume; the 5F2H was a little fuller, it made the Pro Jr sound a bit boxy. I’m looking forward to putting it all carefully back together with an excellent harp speaker and thrashing it out. I’ll post a full review with sound clips next week.


UPDATE 11/06/08: Here is a shot of the reassembled amp with the Weber 12F125-O speaker. You’ll notice I swapped a coke-bottle 5V4 tube for the Copper Cap solid-state rectifier. I also added finish washers to the mounting screw on both back panels, and lock washers to the chassis mounting bolts. Everything is tight and squared away now.


The ceramic speaker gave me a little more room for the KT66 tube. The mounting holes for the chassis are slotted, so I slid it as far as I could toward the baffle. When I got the amp the big tube was crammed between the alnico magnet and the back panel, actually touching both. Now it runs free…

This amp is dead quiet. Even at full volume you don’t hear any tube hash. It’s pretty heavy for a small amp at 32.2 pounds. The big output iron and the ceramic speaker make it hefty.

I’ll post sound clips and a full review soon.

Sunday, October 12, 2008

Open- or Closed-Back Cabs for Blues Harp?

You may have noticed that I have a propensity to test conventional ideas. When I decided I needed a speaker cab I went with a closed –back design, while almost all harp players seem to prefer an open back cab when using separate cabs and heads.

I liked the way some closed-back cabs sounded with guitar: Dark and THUMP! I wanted to try that with harp, so I ordered a 2x10 closed back cab from Avatar, thinking I could saw off part of the back panel to convert to a semi open-back configuration if it didn’t work out.

All those cool old tube combination amps harp players use are semi open-back for two reasons: Efficiency and air circulation. Open-back cabs can sound louder than closed unvented cabs, and those tubes get HOT and need airflow.

I’ve played the closed back cab for several months and like the low end, but to my ear it sounded kind of muddy, so I finally got around to removing the back panel and running it across a table saw, cutting off the bottom seven inches.

Now it sounds great! As expected, the cab instantly sounded more lively and open; more musically nuanced, more dynamic. I drove it with my Masco ME-18, which is kind of a darker-sounding harp amp, and also with a Fender Pro Junior and a Fender Champ. They all sounded good, particularly the Champ.

I miss the deep grind I could get with the closed cab when bending a 2-hole draw reed with a tight cup on a lower-tuned harp, but the open cab is more versatile and efficient. So, there are good reasons why some wisdom becomes conventional. Semi open-back cabs sound better.

But if I change my mind I can always put that bottom panel back on the cab and get deep and dark again…

TEST NOTES: The drivers in the cab as I write this are a Weber Sig 10 alnico with smooth cone and a Jensen Mod 10 ceramic. I have a Weber Beam Blocker on the Jensen.

Thursday, October 2, 2008

Ted Weber

I first encountered Weber speakers several years ago when my guitar buddies started raving about them. I was skeptical. Weber speakers just didn’t do it for me.

But when I was later working on my
silverface Champ amp project – creating the ultimate SF Champ for harp – I found that Weber’s 10A125-O speaker was the best sounding blues harp speaker on earth. And I had tried nearly all of ‘em…

I tried the
Weber Beam Blockers, and again they delivered exactly what they promised. The Beam Blockers are now my secret weapon in harp amps.

I found the inexpensive
Weber Signature ceramic 10-inch speaker to be a very good blues harp speaker when I was working on my Fender Pro Junior harp amp project.

I played
Weber’s 5F2H harp amp kit at a blues jam and I thought it was one of the best-sounding small harp amps I’d every heard -- no doubt due in large part to its use of the aforementioned 10A125-O speaker.

So, Ted Weber was developing a pretty damn good batting average with the
Blues Harp Amps Blog. I can be a harsh critic when products don’t deliver the goods, or when they just sound nasty with blues harp. When I decided to try Weber’s Copper Cap solid state rectifier I half expected it to suck. Nobody bats 1.000, do they?

I ordered the 5Y3 version because the rectifier tube in one of my amps was getting noisy, and it gave me a good excuse to try out Weber’s $22 alternative. The bottom line is the Weber Copper Cap rectifier is another great product from Ted, delivering exceptional performance and value. After it arrived and I futzed with it a bit, I ordered another for a second amp. I’ll post a more comprehensive review of the Copper Cap later, but suffice it to say I am very impressed with Ted Weber and his line of products.


UPDATE: FedEx lost the second WY3GT Copper Cap I ordered (it was reported on the FedEx website as delivered but I never got it). Weber shipped a new one as soon as I alerted them about the lost shipment. Good people...

Tuesday, September 30, 2008

Pro Jr Problem: The Top Middle Screw on the Back Panel

I’d read several places online that the top middle screw on the back panel of the Pro Junior amp caused the amp to be noisy, so removing the screw and leaving it out was the way to go. I thought it was just one of those weird online rumors and ignored it. My Pro Jr. sounded fine.

But after I’d taken the amp apart and put it back together several times to make modifications, I noticed during testing that the tone control did not turn as freely as the volume control. It was bound up somehow. Here’s what I found:

The picture above is looking upward at the back of the amp with the back panel removed. The screw hole you see is the top middle screw for the back panel. Below that you can see a rectangular piece of metal; presumably to shield the volume and tone pots from heat or RF signals. The pots are right above it, with the other amp components below.

The metal shield is attached to the circuit board using silicone sealant, and it will move pretty easily. What I discovered it that it can easily get bent upward toward the bottom of the pots when handling the chassis, particularly when you are coaxing the chassis into or out of the cabinet. (It is a tight fit.)

If the metal shield is deflected upwards its free end will be above the top middle screw on the back panel. As you drive in the screw it presses the shield up against the tone pot, causing it to bind up and possibly short.

Problem solved. Just make sure that metal shield is parallel to the control panel just above it and out of the way of the screw.

(BTW, the violet wire at the lower right of the photo is the Negative Feedback Circuit. Follow this wire to the speaker tap, unsolder it and tie it off to give your Pro Junior a slightly coarser harp tone.)

Tuesday, September 9, 2008

Fender Pro Junior Harp Amp Project – Speakers

The original Fender Special Design speaker (made by Eminence) that comes in the Fender Pro Junior amp is very efficient and bright. Together with the high-gain 12AX7 tube in the preamp socket, the stock Pro Junior can be a feedback monster for harp players. A warmer-sounding alternative was needed for this project, but I wanted to keep the cost low. That meant I had to forget about the great Weber VST speakers and used vintage Jensens.

I’d tried the Jensen reissue P10R and C10Q speakers in other projects and didn’t like them. I’d also tried the Weber Signature 10 ceramic with smooth cone and loved it, so I decided to try its alnico twin in the Pro Junior.

Several players have said they saw a drop in volume compared to the original speaker when switching to the Sig10 alnico, and they are right, sort of. Ted Weber describes this speaker as “compressed at high volumes” and he ain’t kidding. This speaker has a nice blat for harp but in the Pro Junior it squeezes the dynamics down a bit too much for my tastes. This speaker is a touch bright (not nearly as bright as the original speaker), making the Pro Junior sound much better but still a little nasal; a little boxy. The compression made the amp slightly monotonous. I could see it in the wave forms when I recorded.

So, I swapped it out for the Weber Sig 10 ceramic I already had on hand. The difference was immediate. The ceramic speaker is a little warmer and less compressed. The amp responds better to mic cupping; it is less boxy, more open and lively; more articulate. To my ear, the ceramic sounds much better.

You be the judge. Here are clips of each speaker in the Pro Junior, recorded under identical conditions.

Weber Sig10 alnico, smooth cone
Weber Sig10 ceramic, smooth cone
NEW: Shure SM57 mic, Weber Sig10 ceramic, smooth cone

The smooth cone in both these speakers promotes earlier break-up and a warmer tone, ideal for blues harp. The amp is not stock: I have replaced all the tubes with harp-friendly options:

NOS JAN Philips 5751 preamp tube (lower the gain slightly)
JJ 12DW7 phase inverter tube (unbalanced wave form for a fuller tone)
Electro-Harmonix EL84 power tubes (warmer versions of the EL84)
I also disconnected the negative feedback circuit. (a little more “dirt” in the tone)

I like the way the Pro Junior sounds now, although I need to take it out and run it around the block in gigs or blues jams. So far, it sounds great for a low-buck project. Total for the used amp and new parts was under $300.

UPDATE: That great-sounding ceramic Signature 10 speaker from Weber is only $30.00, ten dollars less than the alnico version. The cost of this project is only $280.

TEST NOTES
: The Fender Pro Junior amp was set at volume on 4, tone on 4. The amp was mic'ed with an AT2020 condensor mic about 10 inches in front of the amp, slightly off axis. Harp mic had a Shure CM element; harp was Hohner Marine Band Deluxe in B-flat. No effects of any kind were used on the amp or in the recording or editing. The backing track was from a Boss DR-3 drum machine. No animals were harmed during the production of this test, but my dog looked at me kinda funny...

Friday, September 5, 2008

Review: Adam Gussow’s “Amping the Harp“

Frequent visitor to this blog and master harp instructor Adam Gussow has produced an hour-long video devoted exclusively to getting good blues harp tone out of an amplifier, Amping the Harp. This is must-see Amp Tone 101, it costs a measly five bucks, and it belongs in every blues harp player's reference library.

Adam knows what he’s talking about. His tone is the real deal, developed over many years as the blues harp half of Satan & Adam, starting out on the streets of Harlem. The video features his five harp amps and what he likes about each one. The magic of this video is the “Aha” moment you feel when you hear the amps begin to “sing.” Adam is a skilled teacher (Professor of Blues History at Ole Miss) and an immensely talented player who makes complex concepts simpler – even the black art of blues harp amp tone.

The package includes a reprint of an article he wrote for The American Harmonica Newletter in 1993, “Adam’s 10-point Guide; How to Amplify Harmonica for that Great Sound.” The topics include:

-Microphones
-Tube vs. Solid State
-Speaker Configuration
-Volume and Tone Controls
-One Amp vs. Two
-To Elevate or Not to Elevate
-Amp Placement
-Miking Your Amp
-Reverb Units, etc.
-Putting it All Together.

The production values on the video are not high… It is Adam with a small digital camcorder. He must have just had six cups of coffee because he is his usual manic self and he takes a “pause for the cause” several times. Still, the video is worth many times the tiny cost.

There are a few places I disagree with Adam. He makes the blanket statement that NOS (New Old Stock) tubes are better. Maybe, but there are vendors out there who will sweet-talk you into parting with a ton of money for tubes they swear will turn you into Big Walter Horton, but sound no better than some inexpensive new production tubes. Caveat Emptor.

Also, Adam insists on using his Mouse amp (a small, bright, portable solid state amp) in tandem with his great vintage amps. He calls the Mouse his “tweeter.” It gives his tone a quality not everybody likes. (I think it sounds great, but it ain’t my favorite Chicago sound.)

Adam does not go into the minutia of tube swapping and other electronic mods, but his advice and examples are solid gold. Any harp player who watches this vid will have a better understanding of harp amp basics.

Go to Adam's
store on his website, Modern Blues Harmonica. Scroll down until you see “Amping the Harp." Click on the link to take you to TradeBit to complete the transaction. I paid using PayPal and the transaction was quick and flawless.

The Blues Harp Amps Blog gives Adam Gussow’s “Amping the Harp” video a V on the I-IV-V scale. Very highly recommended.

Friday, August 29, 2008

Fender Pro Junior Harp Amp Project - Sound Clip 1

Here is a short recording of the Pro Junior project in a transitional state -- the only thing missing is the new speaker. In this configuration the PJr has the 5751 preamp tube, the 12DW7 phase inverter tube, the new pair of EH EL84 power tubes, and the negative feedback loop has been disonnected. Check it out.

That is pretty remarkable. The Pro Junior has nice grind with the volume on TWO! Tone is on four. The original speaker is a little bright for my tastes, but this little amp is starting to have some real character. I can't wait to hear it with the Weber alnico speaker.



Jump to Fender Pro Junior Harp Amp Project – Speakers

UPDATE: Just for fun, here's a short clip of the PJr amp running through my 2x10 cab.

Wednesday, August 27, 2008

Pro Junior Harp Amp Project: Progress Report


I’ve finally settled on the main components for the Fender Pro Junior harp amp project. I tried to keep the cost low so I wouldn’t violate the low buck nature of the original amp. Thanks for all your suggestions.

Speaker – Weber Signature 10 alnico, straight cone – $40.00

This took a lot of thought and research. I looked around for used premium speakers and found a Kendrick Blackframe, but the deal fell through. True vintage speakers were just too much to spend on this project. I dislike the Jensen alnico import speakers for harp, and the C10Q by itself would be not much different than the stock Eminence.

After trying many speakers and consulting with speaker vendors and amp builders I decided on the Weber Sig 15-watt alnico. I use its ceramic twin in a different amp and like it a lot. The straight, un-ribbed cone gives the speaker a warm crunchy tone, with early break-up and a punchy sound. This should be killer in the PJr project.

Preamp Tube – NOS JAN Philips 5751 -- $20.00

Harp players often swap out stock preamp tubes for lower gain tubes, to reduce feedback and increase power tube distortion at lower volumes. My favorite tube for this when using small amps has been the 5751, which has a gain factor of 70 percent when compared to the stock 12AX7. Harp players often use the 12AY7, but its gain factor of only 45 percent sometimes sucks too much power from amps that are already volume-challenged. I have a used Sylvania 12AY7 I’ll also try in the Pro Junior.

Power Tubes – Electro-Harmonix EL84 -- $20.00

The EL84 family of power tubes is known for a bright sound with chiming overtones. That is great for guitar but not so good for blues harp. The EH EL84 tubes claim to have a warmer tone with less accent on the highs. (And they’re cheap.) The power tubes in the Pro Junior amp look to be originals, so replacement is a good idea anyway.

Phase Inverter Tube – JJ 12DW7 -- $10.00

I wrote extensively about the feedback-fighting properties of this tube here. But in this project I’m not so much interested in that as I am in the tone the 12DW7 can bring to the Pro Junior. This tube is unbalanced, causing the two power tubes to work at unequal levels. The result is a slightly more ragged edge to the harp tones, with a fuller sound. I’m also thinking of trying mismatched power tubes.

Total for parts -- $90.00

All the tubes were purchased from Tube Depot in Memphis. The speaker was ordered directly from Weber. With shipping costs included the total may go slightly over my $100 limit. If you work eBay and Craigslist really hard you can probably assemble the components for less.

The only other modification was to disconnect the negative feedback circuit in the amp. That amounted to un-soldering the violet wire that runs from the center of the circuit board to the speaker jack. I taped it off and secured it out of the way with a zip tie. I also sprayed the tube sockets with some Deoxit.

So, we’ve added 90 bucks worth of stuff to a little $200 used amp in search of better harp tone. How does it sound? So far, it sounds outstanding; a gigantic improvement over the sterile, guitar-ish tone of the stock Pro Junior. I’ll post sound clips next week after the new speaker arrives and I have a chance to sort it all out. Stay tuned…

Friday, August 22, 2008

Update on the Pro Jr. Project

I’ve received several emails with good suggestions for the tube and speaker swaps in the Fender Pro Jr harp amp project.:

-12AY7 in V1 (suggested several times)
-12AU7 in V1
-12AT7 in V2
-12DW7 in V2

(V1 is the preamp socket; V2 is the phase inverter)

-Jensen C10Q reissue speaker

-Weber 10 Sig alnico straight cone speaker
-Weber 10A150 speaker

I emailed Ted Weber and he suggested a 10F150-O, but that costs 90 bucks and I’m trying to keep this project down to a moderate level. I’m still looking around for an interesting used speaker. If nothing turns up I’m leaning toward the Weber Sig ceramic with straight cone. I use that speaker in my 2x10 cab and I know it sounds great with harp.

I ordered a NOS JAN Philips 5751 preamp tube from Tube Depot in Memphis. On a whim I visited my friend Al in his tube heaven junk store and found an old used Sylvania 12AY7 with some corrosion on the pins. I’ll try and clean it up and see how it sounds.

In the article about my Fender silverface Champ project I dug into the issue of the Negative Feedback Circuit in Fender amps and how it affects harp tone. The NFB circuit in the Pro Jr. is a violet wire that extends from the middle of the circuit board to the speaker jack. I’ll unsolder or clip the wire and tape it off. Some players install a switch or pot in the circuit to adjust the NFB, but with the Champ project I discovered that zero NFB is best for my tastes.

I had heard that the green filament heater wires in the Pro Jr are not twisted and are routed along other wires that could easily pick of noise from them. In my Pro Jr. they aren't twisted, but they are dressed pretty well, crossing other wires at a 90 degree angle. The amps does not seem noisy so I'll leave well enough alone.

The Pro Jr. has a bleed circuit that drains the amp of any power within a few seconds of shutdown, which is supposed to keep you from getting shocked. Still, I short the no. 1 pin of the V1 tube socket to ground for extra caution before working on the guts of any tube amp. I suggest you do the same.

Jump to Fender Pro Junior Harp Amp Project – Speakers

Wednesday, August 20, 2008

Harp Amp Project: Fender Pro Junior

The other day I spotted a MIM (Made In Mexico) Fender Pro Junior at a very fair price on Craigslist, so I snapped it up. I owned a Blues Junior amp a few years ago but did not like it much. I may have given up on it too early. So now I’ll take a shot at its simpler little brother, the Pro Junior.

Where the Blues Junior is a Master Volume amp with a FAT button and all manner of bells and whistles, the Pro Junior is bereft of features. It has two chicken head knobs: volume and tone. That’s it. One channel; no reverb. The speaker in the Pjr is a 10-incher, two inches smaller than in the Bjr,

What the two amps share in common is basic circuitry: 15 watts, two EL84 power tubes, a solid state rectifier, 12AX7 phase inverter, and a 12AX7 preamp tube. They also share the EL84’s tendency to sound trebly and to chime when driven hard. That is not a good sound for blues harp.

Be that as it may, the Pro Junior is a pretty popular harp amp. I’ve heard passably good tone honking out of these little amps at blues jams. Some of my harp buddies swear that this or that speaker swap is the magic bullet that transforms the Pjr into a monster little harp amp.

This particular Pro Junior looks to be completely original, and it is in excellent shape, the tolex and grill unmarked. The tubes are all Fender/Groove Tubes/Sovtek and are almost certainly the tubes that came with the amp from the factory. The speaker is the original Fender Special Design. I played the amp and it sounds like… well, it sounds like a stock Pro Jr.

I’m looking for suggestions here. The basic plan: I’ll replace all the tubes. For the preamp tube I’ll start with my favorite, the NOS JAN Philips 5751. In the power section I’m thinking of EL84s known for a bigger bottom end and less sizzle, such as the Electo-Harmonix or the new production Mullards. When replacing a matched pair of power tubes you should always replace the phase inverter as well. I’ll try both a new 12AX7 and the 12DW7 I still have lying around from my Twin Reverb project.

I need recommendations on the new speaker. I don’t want to go with my favorite, the Weber 10A125-O, for two reasons: It is rather expensive and I already use it in my silver face Champ (it sounds amazing). I also don’t want Jensen “vintage” or MOD, or the Weber Sig. I’m thinking maybe a used speaker, or something different. What have you tried that sounded good?

I also want to limit the mods to those that can be accomplished without being (or hiring) an EE. I’ll try to disconnect any Negative Feedback Circuit in the Pjr, but I don’t really want to dive into the complexity and expense of slinging a soldering iron all over it, unless the mods are REALLY simple. My target is to radically improve the harp tone of the Pro Junior with, say, a hundred dollars worth of parts and with me -- a lay tinkerer -- doing all the work.


I welcome any suggestions either in the comments below or via email to me at bluesharpamps@gmail.com
.

Jump to Fender Pro Junior Harp Amp Project – Speakers

Friday, August 15, 2008

Review: Danelectro Fab Echo pedal


First of all, this pedal sells for $14.99, about a tenth what you would expect to pay for a decent delay pedal. That, and a smattering of positive reviews from guitar players got my attention.

The Fab Echo is not long on features, of course. But it does one thing rather well… it has a nice warm slap-back that works well for harp.

Harp players argue constantly about which delay pedal is best: Analog or digital? Maxxon, Ibanez, Boss, or Digitech? If you are a Chicago-style blues player – if you lust after Little Walter’s tone – all those delay pedals have way more features than you will ever need. What sounds good for traditional amped blues harp is a touch of greasy slap-back echo. That’s all.

And that’s where the Danelectro Fab Echo comes in. It has two controls, Repeat and Mix. The repeat knob controls the number of echos, with a single echo at the minimum position. That is what we want for harp. The other knob controls the output mix of dry and wet signals, from all clean to all echo. Essentially, this is s a one-knob pedal for harp players.

What you pay all the extra money for in other delay pedals is the Delay Time control, which is conspicuously missing from the Dano Fab Echo. But if you only use one echo – a “slap-back” – then the lack of a Delay Time control is pretty much meaningless.

I recorded three very brief sound clips to give you a basic idea of how the Dano Fab Echo pedal sounds for blues harp. The first clip has the Repeats control at the minimum (one slap) and the Mix control at the max (all echo, no clean). This clearly illustrates the delay time built into the pedal, but you sure would not want to use it this way.

Clip 1

The next clip has a similar riff, with the only change being the Mix control is at 50 percent. The pedal sounds best to me at this setting

Clip 2

For reference, here is a very short clip with the pedal switched off.

Clip 3

How do you think the Dano pedal sounds? For its price and simplicity I think it sounds good, but lately I have preferred playing dry… no reverb or delay at all. But, Crikey! For chump change you can have a usable no-frills slap-back pedal in your bag of tricks. At the very least it makes a great back-up if your fancy delay pedal (most of whose features you never use) ever craps out.

Observations:

This pedal is made of plastic, but it is hefty and feels solid. The jacks are soldered onto the circuit board but don’t feel loose or cheesy. Product support at Danelectro is known to be pretty much non-existent, but if it breaks, what the heck. Just buy another one.

This pedal is not noticeably noisy. The pilot LED is a brilliant blue. The controls are a little confusing at first because they face away from you as you look at the pedal. It has a 9V power connector so you can use a common power adaptor instead of hassling with batteries.

I ordered it on a Monday evening from Musicians Friend online, and it arrived at my house in Denver via USPS express mail on Thursday morning.


Test Notes:

I used a OneSpot adaptor to power the Dano pedal. The amp was a vintage
Masco ME-18 and 2x10 cab. The recorder was a Zoom H4. Instead of mic’ing the amp, I used the H&K Red Box Pro DI to avoid room effects. The harp mic was a Peavey H5 Cherry bomb with Shure CM element. The harp was a Hohner Marine Band Deluxe in the key of B-flat.

Thursday, July 31, 2008

Gary Smith/Aki Kumar - Rocket Ride



Here is a great vid of Gary Smith (on the right) playing a harp duet with Aki Kumar, an excellent young player.

Both these guys are playing through Sonny Jr. amps: Gary is using his Cruncher and Aki is using his SJ410.

Nice tone...

Wednesday, July 23, 2008

Gary Smith endorses the Sonny Jr. Cruncher Amp

Gary Smith, whose legendary tone earned him the title of Godfather of the South Bay Blues, has endorsed the Sonny Jr. Cruncher amp. This is a very big deal for a lot of reasons.

I had heard about this endorsement but I was skeptical. Gary has always been a vintage Fender guy. In fact, his award winning DVD “
Amplified Blues Harp Demystified” is mostly a celebration of the magic of vintage Fender amp tone. For Gary to get behind a different amp now is, as I said, a very big deal.

Anybody who has heard Gary Smith play live or has heard his CD “
Blues For Mr. B.” or on Mark Hummel’s “Blues Harp Meltdown” knows that Gary has the most beautifully articulated Chicago-style tone on the planet. Listen to the first few bars of You Can’t Hurt Me No More or Elevate Me Mama for an object lesson in blues harpology.

That is why this is such a big deal. Gary honed his extraordinary tone over the last 40 years using mostly Fender gear. His main gig rig of late has been the venerable Fender Bassman. For him to change up now is a huge risk of upsetting the perfect tonal apple cart. He had to be mighty impressed with the Cruncher amp to do this.

He is. I had a conversation about this with him last night. Gary Smith fully endorses the Sonny Jr. Cruncher amp, and will be using it at all his gigs. In larger venues he will add the Bassman for back-end support while mic’ing the Cruncher through the FOH speakers. At all other gigs it will be the Cruncher by itself. What he likes about the Cruncher is the complex tone from the multiple speakers of different sizes and configurations. He told me the Cruncher throws to the back of the room with ease. He walked around while another player used his un-mic'ed rig and said it sounded “right there in the front of the mix.”

As you may be able to tell, I am very impressed with Gary Smith as a blues harp player. He is the real deal, and he is an expert on harp amps. If he sincerely endorses the Sonny Jr. Cruncher – and I am convinced he does – then that is good enough for me. Yes, I have had my differences with Gary Onofrio, the owner of the Sonny Jr. brand, but this is impressive and cannot be ignored. Also, Onofrio was a stand-up guy in helping me hook up with Gary Smith.

Sound clips of Smith playing the Cruncher are on the way and will be added to this post soon. I’m still working to get a Cruncher amp in my hands for a thorough review. Check back for more details on this.


Sonny Jr. Amps

Wezo Megatone Amp

Mike Wesolowski sends along photos and a spec sheet for his very interesting new project, the Wezo Megatone amp, a hot rod harp amp based on the Epi Blues Junior chassis:







Details:

Rugged point to point construction and top quality components
carbon comp resistors
Mallory 150 signal caps
Sprague and JJ high voltage caps
over sized transformers
high capacity power supply
pre-amp tubes: 12AU7, 12AX7

30 watts from a pair of EL34 power tubes, each with separate fixed bias control
unmatched tubes can be used
other tube options: 6L6, 5881, 6CA7, KT66, KT77, KT88, 6550
high capacity whisper fan for tube cooling

Asymetrical Attitude drive control delivers thick, feedback resistantcrunch tone

Variable Mic Pad, will accomadate any type of unbalanced microphone

Other controls: Gain Boost (switch), Volume, Mid Boost (switch), Bass, Treble

Rear Panel Controls:
Line out jack, feed speaker voiced signal into 2nd slave amp or mixer board
Ground lift switch, safely and effectively eliminates ground loop noise
8 and 16 ohm speaker jacks
mains and high voltage fuses
With two EL34 power tubes this little dog will have a serious bark. I hope to have sound clips, release date, and price points soon. Contack Wezo at mwesolowski@triad.rr.com

Sunday, July 20, 2008

Rhythm Tech Mountable Gig Tray

I was enjoying this new vid posted by Adam Gussow of Satan & Adam and noticed he is using the Rhythm Tech Mountable Gig Tray. Check out the mic stand on the right side of the picture.





I've been using that piece of gear for about a year. It's great for harp players... It's a handy staging area for harps and mics between your harp case/gig bag and the performance.


Keeping your harps and mics handy during a gig has always been a problem. Some players go to a lot of trouble to have their entire harp collection on stage in a big case within easy reach at all times. I found that to be a huge pain. With the MGT I can line up the harps I know or suspect I will need in the next set, and they are right there mounted on my vocal mic stand. The MGT has a rubberized mat to avoid clinks or handling noise, side rails to ensure your harps don't get knocked to the floor, and even a hook underneath to hang a towel or chamois or mic or whatever. Very, very handy, and very well made.

As the name suggests it is made for rhythm players, to hold maracas or tambourines or shakers, but it is also ideal for harp players. It is a good place to put your beverage, as well. They sell for about 40 bucks at all the usual places. Highly recommended.

Masco, Alamo, K-Zoo Amps For Sale

Here are some great harp amps offered for sale by a guy who is pretty well-known in the harp community. I see his email/handle in many harp-centric sites on the web: rbeetsme@comcast.net.

Masco Combo amp -"These rare combo amps rarely show up for sale. Mine has a fair amount of cosmetic "patina", cool look. The amp itself is really nice looking, no rust or corrosion. It works fine but is original, some pops and crackles, pots are a little scratchy, speaker seems fine. I would recommend a good amp tech. The guy here is one of the best in the midwest but takes a year to look at your stuff unless you're a rock star."

Alamo Model 3 -"This is the highly desirable wooden cabinet model, sounds terrific, rivals my Kendrick Champ,probably louder! Killer for harp! I have seen some really high prices for these on ebay in the last year. Exc. shape."

Alamo Capri -"Small practice amp in very nice cosmetic shape, sounds similar to a Harmony but i think a bigger sound, Alamo amps work well for harp."

Kalamazoo II -"Greg Heumann went hrough this one, superb player, looks nice too."

Offers are invited for these collectible gems. Email rbeetsme@comcast.net.

[Dang! I might throw down an offer on a couple of those bad boys... -Rick]

Thursday, July 17, 2008

So Far, So Good


Since I started this blog back in March we have had over 16,000 page views, with the average visitor staying more than three minutes. Our readership grows every week. Not bad for a new, narrow special-interest blog, and people are returning again and again to read the articles. Most new visitors get here by searching Google for info on harp amps.

It is interesting that less than 60 percent of our visitors are from the United States. This blog has attracted visitors from over 40 different countries.

Plans for the future include more long-term hands-on reviews of harp amps in real-world situations. I’ve gotten commitments from some amp vendors and builders to loan me their gear for review, or to help me find an owner willing to share his gear. I’ve been in contact with several of the best harp players out there to discus gear and tone. More on that later.

Thank you for visiting my blog. Check back again as the quest for tone rolls on...

Wednesday, July 9, 2008

When Should You Amp Up?


It never fails. Every time a newbie inquires about amps on a harp forum, a crusty old harp veteran will fire back with the moldy cliché that Tone Comes From the Player, Not the Amp! This is invariably followed by other crusty old harp veterans who opine that said newbie should not even THINK about getting an amp until he has acquired good acoustic tone first.

To the first, I say “Duh!” To the second, I say “Nonsense!” Do these curmudgeons also get cranky with guys who buy certain sneakers, growling that the shoes won’t make them play like Michael Jordan? Thanks for illuminating the obvious, fellas.

If a new player (or any player for that matter) admires the tone he hears on recordings or at gigs, he will be curious about the rig the player used. However, no reasonable person would expect to instantly play harp like Jason Ricci after buying a HarpGear 50 amp. But there is nothing wrong with being inspired by the sound of the amp.

Harp players should never be discouraged from amping up. I put my students on the mic from the very first lesson. Every session ends with a few minutes of amplified playing and a brief discussion of amps and mics. Any harp player who has ever stepped up to a mic knows very well that bad harp playing sounds even worse when amped. Amps and mics are incentives to work harder and develop your tone; they are never a crutch for bad tone.

The notion that beginners should not start thinking about amps is absurd. Some crusty old veterans warn that new players might buy the “wrong” amp, or might over-buy. Maybe, but I haven’t seen many beginning harp players lugging boutique 4x10 amps to blues jams. And the decision about which amp is “right” for a player can only be made by the player himself after a lot of experience.

My advice to a new player interested in playing amped blues harp is to get a small tube amp and bullet mic right away. Practice with your rig every day. Before you know it, you will have developed your own tone.

Tuesday, July 8, 2008

Hurricane V8 harp amp on the market



Brian Purdy at HarpGear.com has a very interesting little amp for sale: a Hurricane V8.

I have a mint used Hurricane V8 amplifer for sale. This is the same model amplifier that Rock Bottom played exclusively in the last years of his playing. They have been discontinued for a few years now. It is in perfect condition with a D2F padded cover.
Here is a short demo of the Hurricane V8 amp in action, posted by a friend on YouTube. Nice tone.

Monday, June 30, 2008

Review: Harp Gear Double Trouble

[The Blues Harp Amps blog sends a big "Thanks!" to Joe for his generous contribution of this review.]

About four years ago, I started playing the harp again after laying off for a number of years. Living in the San Francisco Bay Area, there are a lot of harp players. There are almost as many Blues jams. I started hitting a few of them. I was able to try out a lot of different amplifiers.

In the past two years, I've owned several amps. Each of them had their own good and bad points. Tonally, I didn't have any issue with any of them. The main challenge that I had was finding a balance of volume and portability. Some amps were not loud enough. Others were too loud and not very portable. I found a good balance by picking up a Harpgear Double Trouble.

It's a killer amp that packs a surprising punch and is extremely versatile. It has a lot of great tones available in a nicely sized package. It's a righteous balance of portability, tone, volume and feedback resistance.

Portability - This amp is about as wide as a tweed Champ and about almost two feet tall. In the standard configuration, it features two 8" Weber Alnico speakers that are mounted vertically in the cabinet. I am going to guess it weighs less than twenty five pounds. It easily fits in the passenger seat of an average car. One can easily carry the amp in one hand and a suitcase full of harps in the other hand.

Tone - The tone control is incredibly useful. Leave it turned off and you'll get a nicely distorted tone. Turn it up and the tone cleans up nicely. You can dial in as much high end as you wish. The higher the tone control is set, the better the amp punches through the mix. It's a very useful control.

Volume - This amp has two 6V6 power tubes delivering 18 of the loudest and most useful watts around. In the stock configuration, it gets pretty darn loud. It is much louder than a Pro Junior or a Blues Junior. It isn't quite as loud as a tweed Bassman, but it can be very loud. It sits very comfortably on a chair. It's been played in some really loud places. I haven't been in a situation where I or the audience couldn't hear it.

Feedback Resistance - Battling feedback is a problem for most people playing amplified harmonica. One of the nicest features of the Harpgear Double Trouble is very feedback resistant. Feedback doesn't usually set in until the amp is close to the end of the sweep of the volume control. Depending on the microphone, it can be as high as 8 on the volume control. (Which is very loud.) Rarely, have I ever needed to turn it up that loud.

This amplifier sounds good with every microphone I own. A few months ago, some of the people on the Weber Harp BBS where posting sound clips of their amps on youtube. I contributed a couple of this amp with a couple of different microphones.

The first clip is a Shure 545 dynamic microphone plugged into input #1, volume at 6, tone on 10. Hohner Big River Harp key of A.



In the second clip, I am using an older MC-151 equipped Hohner Blues Blaster plugged into input #1, volume at 8, tone on 0. Hohner Big River Harp key of C.



Finally, another nice feature of the Harpgear Double Trouble is that it doesn't cost as much as a house payment or an annual IRA contribution.

[For more from Joe visit
Joe's Blues Blog.]

Sunday, June 29, 2008

Custom vs. Vintage


Which is best? New custom harp amps or tweaked vintage guitar amps?

I had an interesting conversation about harp amps recently with a good West Coast gigging blues harp player. He was very skeptical of harp-specific amps because of their one-trick nature. I think he preferred to start with vintage guitar amps and tweak them to his tastes, which include a broader tonal palette.

That frames the choice pretty well.

Getting good harp tone out of an amp can be a delicate balancing act. You need low-watt speakers that are always on the edge of breakup. You need to tame the input section of the amp to avoid screaming feedback. You want to tip the amp into overdrive when you put a tight cup on your bullet mic. And you want all of this to stay balanced at a variety of volumes and in different venues. Yikes!

People tend to defend their choices, especially if they shelled out a considerable amount of money on them. Owners of boutique harp amps often say they grew tired of trying one amp after another looking for good harp tone, and they finally ended their quest by spending a lot for a specialty amp. But my West Coast friend has a good point: Harp specific amps usually have one voice (usually tube overdrive), and they are tuned to the ear of the builder.

[To be fair, one harp amp builder who springs to mind hawks his 4x10 amp as versatile. He even ships extra tubes with the amp to vary the tone. But if you are jacking tubes in and out of an amp to sculpt the tone you are back to tweaking, same as the guy with the vintage guitar amp. What did you spend all that money for?]

Getting good harp tone out of an amp may be tricky, but it is not rocket science. There are a few basic principles to keep in mind:

-> A bullet mic puts out about fifty times more energy to the amp than a guitar. This exacerbates the fundamental feedback problem that stems from walking around on stage with an open mic in front of a powerful amp. You need to lower the gain of the amp input section. Guitar amps generally use 12AX7 tubes for this, but you should substitute lower-gain tubes such as the 5751 (my favorite tube for V1) or the 12AY7. Some harp guys use the 12AU7 tube but it is not truly interchangeable with the 12AX7 since it draws more current and using it may damage other components in your amp.

-> The lower-gain tubes should be used not only in the preamp sockets, but also in the Phase Inverter (if you have multiple power tubes in your amp). The PI has a gain component as well.

-> The 5Y3 tube is often standard as the rectifier tube, and it works well for harp.

If you buy a boutique harp amp the builder will have already made these choices for you, but the combinations and permutations of various tubes (and their effects on tone) are nearly endless. You will surely fined yourself tweaking your amp, whether it is a new custom or a smelly old vintage.

As I mentioned earlier, you will want to use low-watt speakers. You gotta resist the guitar player’s urge to go for speakers labeled as 100 watts, or other nonsense. Those speakers will be stiff and lifeless in your harp amp. 15 to 25 watt speakers work well, either alnico or ceramic. Ribbed cones sound cleaner; smooth cones break up earlier.

Harp amps with multiple speakers sound best with non-matched drivers. Use both alnico and ceramic speakers in the same cab. Use eight-, ten-, or 12-inch speakers in the same cab. Use speakers from different vendors, such as Jensen and Weber. And don’t spend a fortune on speakers… Harp amps often sound best with medium priced speakers, not elite guitar speakers. My favorite harp speaker is the Weber 10A125-0.

Some harp guys insist on using only expensive New Old Stock tubes, but I’ve found some newer tubes sound fantastic and cost a fraction of the price. Try the Tung Sol new production tubes in both the input and power sections. To my ear they produce excellent warm tone.

So which is best? A new custom harp amp or a tweaked vintage guitar amp? If your skills as a player are progressing (and your skills should always be progressing) you will eventually grow beyond the capacities of your amp, be it a custom or a vintage. Unless you are congenitally disinclined to tinker, you will likely start tweaking your amp to broaden its range of tones. You may start asking yourself why you paid all that money for a boutique amp in the first place.

[Note: The mods I have suggested do not include many other things you can do to improve tone, but those other changes usually involve a soldering iron and a multi-meter. The mods I have listed will have a dramatic and immediate effect on tone. As always, use care when modifying any tube amp. There are voltages that can kill you, even if the amp has been off and unplugged for some time.]

Tuesday, June 17, 2008

Ronnie Shellist; Great Tone



Ronnie's amp is a 5E6A Bassman kit from Weber built by Gerry Hundt. His mic is a vintage Green Bullet. He plays with no reverb or effects, straight into the amp. Freakin' great tone, eh?

Wednesday, June 11, 2008

Testing the 12DW7 Phase Inverter Tube

A few years ago there was a lot of buzz on Harp-L and other Internet harp boards about the 12DW7 tube as a phase inverter in harp amps. I think Gerald Weber started it all when he discovered that an unbalanced phase inverter fattened up the tone and allowed the amp to be turned up to ridiculous volume levels before acoustic feedback occurs. Weber did this by inserting a potentiometer in the phase inverter circuit so he could dial in the exact imbalance level by ear, but the theory persisted that your could achieve the same thing with the unbalanced 12DW7 tube.

A little background…

In most tube amps with multiple power tubes, another tube (usually a 12AT7) takes on the job of splitting the signal to the pairs of output tubes and inverting (or reversing the polarity of) one of the streams. That way, one pair of power tubes pushes the speaker out and the other pair pulls the speaker back. This makes your amp more efficient. Weber discovered that an unbalanced signal – a signal where the push is stronger than the pull – improved harp tone and resisted feedback.

Tubes in the 12AX7 family, including the 12DW7, are dual triodes. That means they are actually two tubes in one. All the other tubes in the family are balanced, with both internal triodes presenting the same amount of gain or amplification. The 12DW7 is an odd duck, with one side having the same gain as a 12AX7 (a gain factor of 100) and the other side having the same gain as a 12AU7 (a gain factor of 20). As a phase inverter, this thing presents a very unbalanced signal to the power tubes.

On to the test…


Well, I was keenly interested in the feedback resisting part of this theory, but I never found anything online that persuaded me this really worked. I was not interested in using the 12DW7 to fatten the tone; there are other ways to do that. But if the 12DW7 was a feedback killer it would be gold.

So I ordered a JJ Tesla 12DW7 (ECC 832) from
Tube Depot in Memphis. I planned to try it in an amp where it could do the most good: A 1972 Fender Twin Reverb. This amp is a 100-watt high-gain beast, restored to original condition and unmodified for harp. It has a fresh quad of 6L6GC EH power tubes and an EH 12AT7 phase inverter. When turned up, it feeds back through my harp mic like nobody’s business.

For this test I placed a Zoom H4 digital recorder 4 or 5 feet in front of the Twin and let it capture the entire test. First I played for some time with the normal 12AT7 phase inverter in the amp, using a C Special 20 harp and my
Peavey Cherry Bomb mic modified by Greg Heumann. Here are the amp settings on the Twin:

Reverb Channel, Bright switch off.
Channel volume – 9
Treble – 1
Middle - 5
Bass – 10
Reverb and Vibrato are off

The 1972 Fender Twin Reverb is a master volume amp, but without the cheesy pull-boost. I rolled the master volume up to 3 ½ before feedback. The amp sounds good like this. The Altec speakers in my Twin are much less bright than the standard CTS speakers or the optional JBL 120s. To be sure, it ain’t Big Walter, but it ain’t bad, either. It sounds as you might imagine… kind of like an overdriven guitar. I like it.

I swapped the 12DW7 tube into the phase inverter socket and resumed the test. I sat in exactly the same spot with the same harp and mic, playing the same riffs. The results were not encouraging. The amp started feeding back at exactly the same place on the master volume. I could hear very little difference in the tone. I tried reversing the polarity of the speaker leads, but could hear no change.

When I first started thinking of doing this test I was talking about it with my friend
Joe Lempkowski, a talented harp player from the East SF Bay. He said he tried it a few years ago but could not hear any real difference. Neither could I.

When I loaded the recording into Adobe Audition I noticed the 12DW7 part of the test was actually slightly lower amplitude and slightly more compressed. When I normalized both tests and listened back to back I could hear a small difference in the tone, but I preferred the stock Twin configuration, not the 12DW7 phase inverter. If others have tried this and had a different outcome I’d love to hear about it

Here is a
link to a brief sound clip from this test. This was stock Twin Reverb, and I’m just tooting along testing different tones. I like the power and presence of the Twin. It worked for Magic Dick, but I don’t need to remind myself that he got that nickname for a reason, and I didn’t. It takes some harp Magic to tame the demon in this amp. The 12DW7 tube was no help at all.

Tuesday, June 10, 2008

The Best Harp Amps



UPDATE:  The best small harp amp on the planet now is the Memphis Mini !!   But for my views of harp amps in 2008, read on.

---------------------------------

Several readers have written asking for my list of “Best” or “Favorite: harp amps, but I have resisted publishing this for a few reasons. I’ve not played some noteworthy amps, and I am burdened with my own biases for or against other amps.

But what the heck… I’m game. I’ve been playing through various blues harp amps for decades. My truly favorite amps are the ones I own, particularly my modified 1970 Fender Champ and my old Masco ME-18 and Avatar cab, but for fairness they will not be included in my list of “best.”

Small Harp Amps – under 10 watts


When I think of small harp amps I think first of a Fender Champ or any of the zillions of clones that use the same basic circuitry: a single 6V6 power tube, 5Y3 rectifier, and an 8-inch speaker. Preamp tubes vary according to taste, usually a 12AX7. These amps are bright and “barky,” and they have a cut-through-the-mix quality that is very satisfying. However, they can be nasal or boxy, and with only 5 watts of power they usually need PA support to be giggable.

Having said all that, every harp player should own a small amp. They have a tone you just can’t get from any other platform. These amps are wonderful for recording and practicing, and for jams.

Best bang-for-the-buck small amps are the Fender Silver Face Champs and the Kalamazoo Model 2. The Epi Valve Jr. half stack is pretty decent.

Of the boutique Champ clones, the best in terms of tone vs. dollars is the little Harp Gear amp. It has exceptional build quality and tone.

Special Mention: The Roland Cube 30 or Cube 30X is a terrific little amp for harp. No, it is not a tube amp, but its tone is excellent, and it is rugged and reliable; indestructible. The built-in amp models and effects are good. I include it in the Small Amp category not because of its power (30 watts) but because of its price. It sells new for about the same money as a decent Silver Face Champ on eBay.

Small harp amps I’ve tried and did not particularly care for: Crate/Palomino, Hohner, Fender Champion 600.

Medium Harp Amps – 10 to 35 watts

The next step up in harp amps starts with amps using two 6V6 power tubes, generating about 12 watts of power. Of all the amps I’ve played or heard in this sub-class, the Fender Black Face Princeton non-reverb amp is by far the best.

Medium harp amps also include the popular Fender Blues Jr. amp. I owned one for a couple of years but never really liked it. It is a high-gain guitar amp at heart, with two EL84 power tubes and a solid state rectifier. I tried tweaking it and finally gave up on it, selling it to a buddy.

One of my favorite medium harp amps is actually a kit from Weber: The 5F2H is an exceptional harp amp using a single KT66 power tube (a relative to the 6L6) and my favorite harp speaker, the Weber 10A125-0. It generates about 22 watts of power and has one of the warmest, roundest harp tones you’ll ever hear. If you lean into it with a tight cup on your bullet mic you get an edgy rasp that sounds just right. This is a great amp.

Other Medium harp amps I like: Fat Dog Amps. Peavey Delta Blues 210. Fender Vibrolux Reverb. 1958 Fender Narrow Panel Pro.


Large Harp Amps – 35+ watts

I think of large harp amps as the rigs you would use with a loud band in a medium to large club venue. They generally do not need to be mic’ed to be heard. They vary in power and speaker configuration.

The tweed 4x10 Fender Bassman from the Fifties is the prime example of a good large harp amp, but these are expensive. The Fender reissue ’59 Bassman amp can also be made to sound quite good. My buddy Ronnie Shellist of the Shuffletones plays through a great-sounding tweed Bassman clone: the 5E6A kit from Weber.

Any list of “best” large harp amps has to begin with the Harp King amps. Their tone is organic and textured at any volume. The Harp King amps can fill a large room with swelling tone and yet they have an uncanny resistance to audio feedback. These amps are expensive and rare, but well worth the money and the wait.

The Meteor amps are outstanding, as are the new HG50 amps from Harp Gear. Both of these are full-on pro gear from good guys who know a thing or two about tone. Their customer service is also excellent.

Any amp Gerald Weber breathes on is spectacularly good. His Kendrick Amps I’ve played are among the best anywhere. And, any amp from Victoria is almost hypnotic in it’s tonal complexity for harp. The best live harp tone I have ever heard came out of a Victoria amp.

Other large harp amps I like: Fender Black Face Super Reverb

So there you have it… My “favorites” list as of this week. I’ve left out dozens of amps, but I guess that is the nature of lists such as this. Let me know your favorite harp amps.