Thursday, January 3, 2013

Blues Harp PA Test

Goofing around with gear; trying to get a gritty sound though the PA.

I set up my PA and played through it using a Shure SM57 mic. The PA is a Mackie 808, the PA we use at clubs that do not have a sound system. I used Mackie C200 speakers.

What I listened for was that slight tearing on the front edge of percussive notes you hear with a nice tube amp. That is the "grit." So I just played the same things over and over and listened.

First I played directly into the PA with everything set flat and the channel trimmed so it was not clipping except on the loudest transients. The tone was as you might imagine: Pretty dry.

Next I cranked the channel trim all the way up and rolled back the master volume. Better, but still not very tube ampish. It distorted but not with the same nice sound you get from a good harp amp.

Then I used a Presonus Tube-Pre between the mic and the PA. I cranked the Drive control and rolled back the Gain control on the Presonus, and backed off the channel trim on the PA a bit. It still clipped the PA channel most of the time.

The preamp did give a bit of that sound. The sound does not have all the moving parts you hear in good tube amps, but if what you want is grit it did have some of that. I thought it sounded pretty good.

I don't think they make the Presonus Tube-Pre any more, but you can get the same effect from an ART Studio Mic Preamp which sells for less than $30.  I've seen Kim Wilson use it.


Leo Moon said...

Thanks Rick, good test.
I've had good results with the Harp Attack pedal through the P.A. The mini tube is a decent sub for 6L6 or 6v6 warmth, for a pedal anyway. It's not likely to match a well-engineered custom built harp amp, either in tone or price. Also still a tweaked Harp Commander I'll likely keep, for its versatility with varied rigs. The H Attack is certainly warmer; the tube is a plus in tone and attack.
I've owned a couple ART Studio Mic Preamps. Did well for a time, but both died in short order, pretty poorly built IMHO.

Jonathan Millett Music said...

Update on the Tubepre- they discontinued it because they just introduced the Tubepre v2