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.

Monday, June 9, 2008

Review: Meteor Harp Amp

[The Blues Harp Amps blog welcomes harp amp reviews from all players. This review of the excellent Meteor Harp Amp is from a friend in St. Louis. I am grateful for the contribution. -Rick]

This is my review of the Meteor harmonica amp based on approximately 3 months of ownership and playing the amp at home and at blues jams. To preface the review, I am an amateur, weekend warrior-type player. I play blues and swing and use a tongue-block embouchure probably 85% of the time (with most of my pucker playing on first-position high end licks). Although I am not currently in a band, I have played in Chicago-style blues and R&B bands in the past.

What I Was Looking for in a Harp Amp

Earlier this year, I reflected on my fleet of three awesome small harp amps (a late-70’s silverface Champ; a 1946 Gibson; and a Hurricane V8 combo amp), and realized they all did the same thing: they achieved a great sound in a small package, but without enough power to be heard in a club setting unless I was willing to mic the amp to the PA and put myself at the mercy of the sound man. I decided to sell off two of the small amps (keeping the Champ) and find a big, loud harp amp with enough feedback-resistant power to play any anticipated situation without going through the PA (I don’t expect to play any large outdoor festivals anytime soon).

Choosing the Meteor

I was a little gun-shy about buying a custom harp amp after a less-than-satisfying experience with a Holland Westside 35 several years ago (problems with customer service, sound quality, and build quality). However, not wanting to spend a lot of time tweaking a guitar amp to suit my needs, I got back into the harp-specific amp market. Coincidentally, the guy who bought the Hurricane amp that I was selling also happened to be an accomplished harp amp builder (not Scott who builds the Meteor), and he had high praise for the Meteor (and I had to agree based on the Kim Wilson Meteor sound samples). Still, I was actually planning to buy an amp made by this other amp builder when a Meteor was listed on ebay by someone in Massachusetts. I put in a bid that I thought would be too low to win, but ended up winning anyway.

First Impressions

I was thrilled when the Meteor arrived at my doorstep in perfect condition – not a scratch, dent, or scuff. I called up Scott, the builder of the Meteor and a friendly guy, and he gave me a few pointers about how to work the controls. Also, several harp-l’ers were willing to share their preferred Meteor settings, which also proved helpful. Within less than an hour of experimenting with various settings in my living room, I was able to dial in a sound that I really liked.

The Outside

The pictures pretty much tell the whole story. The Meteor is covered in a nice and thick brown tweed, with a tan grille cloth and leather handle. The cabinet appears to be pine, not sure if it is finger-jointed. The front of the amp is tilted back such that the speakers point slightly upward, and this seems to make the amp easier to hear on-stage. Instead of a jewel-style “power on” indicator light, the Meteor has a red glowing “M” that is really cool looking.

I also ordered a vinyl amp cover from Custom Amp Covers, Inc. ( for a total of something like $52, including shipping. I selected the imitation leather cover, which fits perfectly and looks a lot better than I expected. I like the cover a lot, and it is also shown in the photos.

The Inside

The amp uses three Weber speakers, that is two 10-inch speakers (Weber 10A125, 10A100T) and one 12-inch speaker (Weber 12A125). As for tubes, there are three pre-amp tubes (not sure if they are AU, AX, etc. since I haven’t removed the metal shields to look), four 6V6GT power tubes (electro-harmonix), and a 5AR4 (Sovtek) rectifier. The photos show the inside pretty well.

The Sound

The Meteor is capable of producing a wide variety of tones from very dark to very bright, depending on the settings. The three different speakers each contribute unique aspects to the sound. The 12” speaker seems to give the amp a lot of bottom end, the kind you can feel vibrating the floor when you play. The 10A125 gives a nice blend of warmth and crunchy breakup, and the 10A100T comes across as exceptionally bright. The combined sound is big and crunchy, yet still well-defined. (The well-defined thing is big for me as I want to be able to articulate notes clearly and not have them get lost in a muddy sound.)

The controls on the amp are volume, “meat,” tone, mid, and presence. The amp has two channels, “Meaty” and “Meatier.” When you plug into the Meatier channel, the “Meat” control knob is active, and this control allows you to increase the volume of the bass frequencies. Either channel gives you plenty of bass, though. The tone knob controls the treble, and by “treble,” I mean “higher frequencies that are relevant to the harp,” not “crazy-high frequencies that cause feedback problems” like you might see with a guitar amp. I typically run the tone between 5 and 9, depending on the key of the harp. The lower the harp key, the higher I run the tone to cut through the mix better. The mid control is one that I do not use very much. In a normal playing situation, I keep this one below a setting of about 2, or it tends to cause screamy feedback, but it does seem to have some utility in filling out the sound if you are dialing in the amp at very low volume (less than a volume setting of 2 for example). The presence seems to sharpen the edge of the sound, and I typically run it between 6 and 8.

The tone controls are tailored to the harp, and one thing that sets the Meteor apart is how useful the tone controls are. With many amps, you pretty much have to set the treble on zero and the bass on the maximum, then crank the amp until just before feedback to get a good sound. With the Meteor, there is a wide spectrum of settings you can use to dial in a variety of tones. The tone controls also seem to somehow affect the overall volume of the amp. You can actually make the amp get loud, even with a volume setting at just 1, depending on how you set the tone controls. When playing in a club situation, I tend to run through the Meatier channel, with the volume between 4 and 5.5, meat between 5 and 6, tone between 5 and 9, mid at 1 (which is the minimum setting), and presence between 6 and 8 when playing with my ceramic element JT30. The Meteor also sounds great through my controlled magnetic green bullet.

Another nice aspect of the Meteor is how sensitive this amp is to microphone cupping technique. I find that I can make a big difference in the sound by just moving one finger a few millimeters.

I also like the huge volume I get with the Meteor without feedback problems. I like to tell the story of the first time I took this amp out and played at a local blues jam. I was called up on stage, plugged in, and blew a few notes. The guy in charge of the sound board immediately started running toward the board, as he thought the Meteor was mic’ed to the PA and set way too loud in the PA mix, but actually, the Meteor was not mic’ed at all. I played nice, however, and turned down my volume to avoid drowning out the rest of the band. Of course, you can still make the Meteor feed back if you are not mindful of your tone control settings, amp placement, and cupping technique. It’s just that all of these issues are completely manageable with the Meteor.

On the Meteor website, there is a quote from Kim Wilson where he refers to the Meteor something along the lines of an amp “in the spirit of Little Walter.” I agree with the Walter-like comparison. This amp is capable of producing that horn-like tone that Walter was known for – similar to Walter’s sound in “Roller Coaster” to my ears.

The Wrap-Up

I am really happy with the Meteor. It delivers the tone, volume, and sound quality I was looking for. The only thing I would change would be to make it lighter-weight. It’s pretty heavy, and it is a little bit of a chore to lug the Meteor long distances or up stairs… still though, this is probably more a case of me being a skinny weakling than the Meteor actually being too heavy, considering the robust, high-quality components. I think
this sound sample provides a pretty good picture of what the Meteor actually sounds like in my hands. Of course, we all sound different, so your mileage may vary.

* * * * * * * *

Monday, June 2, 2008

Jason Ricci's Bassman for Sale

Jason Ricci's backup Fender Bassman amp is for sale. I received this email from Brian at

"I have an interesting opportunity for someone who is into collecting amps. I have Jason Ricci's back up Bassman. This is the amp that he carried and used on the road to back up the "Egyptian" which was his main Bassman he will never part with. This is one of the two actual Bassmans he played through when he was still playing through Bassman amps. I am going to offer this amp on Ebay for anyone who is interested in the opportunity to own this amp. It sounds amazing and is very broke in. Anyone who has seen him play through his Bassman know how good his amps sound. It is in perfect operating condition in the exact shape I got it from Jason. He has engraved his name very small on the corner of the control panel and he has written his contact info on the inside and also signed the inside. "

Jason Ricci switched to the new HarpGear 50, which was a huge coup for Brian Purdy, the talented builder of HarpGear amps. Now Brian offers Jason's backup Fender Bassman for sale. That is extremely cool, and I wish I had room in my collection right now for another big amp. if you are interested you should jump on this quickly before Brian lists it on eBay...