Using a keyboard amp for clean sound

[edspyhill01]

What are the downsides of using a keyboard combo amp as a guitar amp? The choices for guitar amps, no matter the power rating, all have distortion as the main design scheme. Any experiences using a keyboard amp as a jazz guitar amp?

Ed S.

[Franz 1997]

Keyboard amps typically are''voiced'' differently from guitar amps - usually they are designed with a flat response as opposed to to the midrange roll-off capability of most guitar amps ( not all - acoustic image amps are voiced with a roughly flat response, and no doubt there are others).

What this means in practice is that a keyboard amp will probably sound like it has an emphasised midrange, which you may or may not like - particularly with HBs. This may be fine if you have a wide-range middle control so that you can adjust to taste; best thing is to try one.

One reason fender guitar amps are popular for jazz guitar is that they have a big midrange dip built into their frequency response, which fits very well with the midrange peak of many humbucking pickups to produce a beautifully balanced sound, IMO. The guitar pickup is not a ''flat response'' device, and nearly all of them have a peak resonant frequency, whereas a keyboard will produce a more balanced output over its range. Hence, keyboard amps being voiced differently.

Keyboard amps are supposed to be clean sounding, of course; not to get too technical, but the circuitry may well use a different type of transistor from solid state guitar amps, and may sound more 'sterile' for guitar. The kind of transistors ( mosfets, jfets etc) used in guitar amps typically emphasise the 2nd harmonic, and therefore sound ''rounder'' and less harsh.

Just some points to bear in mind. In the end though, if you like the sound, fine!

[eddy b.]

Man I have got to say that I get a killer tone through this big ole Roland Keyboard amp with a 15" and a Tweeter built in...bass for days...however the Treble is a little glassy in a bad way that will never work for "blues", but for solo/chord melody it's pretty sweet..

[jmstritt]

Originally Posted by edspyhill01

The choices for guitar amps, no matter the power rating, all have distortion as the main design scheme.

There are plenty of guitar amps that are designed to stay clean throughout the volume range of the amp. This question comes up fairly often. Can I use a bass amp, a keyboard amp, etc. You can, BUT the difference is that the EQ of the amp is set for the instrument that you are using it with. What this means is that guitar amps are set so that the EQ is adjustable at the points that are most useful for guitarists. Using anything else is going to end up being a compromise.

Guitar amps that are designed to be clean...

Evans
Polytone
Henriksen
Acoustic Image
Roland JC

I am sure that there are more, but those are just a few off the top of my head.

FWIW I played a Roland Cube 80 recently, and for Jazz, using the JC channel of that amp with a little reverb is all you need. 80 watts, 1x12 combo, very lightwieght but rugged construction, and the shop that had it was selling it for under $400.

[kambor]

A keyboard amp is nothing else than a powered PA cabinet marketed for keyboardists so, if you feel like it, you can look for one of those too.

Speaking strictily of guitar amps, I've tried an old unico and a new aer 60 (a limited edition apparently). They both sound great, different from each other but equally good. I've settled on a zt lunchox for portability, if you have a valve preamp it really shines. Evans, Henriksen and Roland are usual suspects too. The new ibanez wholetone seems a good copy of polytone, and maybe more reliable.

As you see, lots of options to torture your dealer a whole afternoon lol

[oldane]

I have an Acoustic Image Corus+ on the way to me. AI amps are very clean - maybe too clean for some - so I may warm it up a bit with a Sansamp Para Driver DI preamp, which I already have, but it could also be done with a good multieffects unit with amp simulations. I could have made the trick with the Sansamp plugged directly into a powered PA speaker (I have tried it, works fine). That way I would have a high powered, good sounding and rather cheap solution. However, the AI amp has many more bells and whistles than that simple PA speaker setup, and everything needed (except the Paradriver - if that is needed) is onboard which eases transport. Weigth only 10kg/20pounds. Small size. Good reviews. Very convenient, very flexible. So that's what I went with.

[jorgemg1984]

Originally Posted by eddy b.

Man I have got to say that I get a killer tone through this big ole Roland Keyboard amp with a 15" and a Tweeter built in...bass for days...however the Treble is a little glassy in a bad way that will never work for "blues", but for solo/chord melody it's pretty sweet..

Add an on / off switch for the tweeter! (any tech can do this in 10 minutes)

About the OP my Henriksen NEVER distorts... I have used it almost all the way up. I never managed to distort my Bandit 65, my M80 or my jazzmaster ultralight amps... I have used this last one fairly loud also and zero distortion. I think it's also hard to distort a Twin Reverb without getting deaf - and even a Super Reverb, Pro Reverb or a Vibroulx can play loud before distortion.... And I am sure amps like Evans or Acoustic Image don't distort. I think Polytones sometimes distort but never with a good speaker on them. So plenty of options...

[cosmic gumbo]

Keyboard amps sound like a PA. A Roland JC120 can stay clean until your ears bleed.

[BigDaddyLoveHandles]

Originally Posted by cosmic gumbo

Keyboard amps sound like a PA. A Roland JC120 can stay clean until your ears bleed.

So true. The only dirt on the JC is dried ear blood.