Acoustic Instrument Processors

Bassman Brad

New member
I have recently been playing in an acoustic trio. Although I perform most of the show on bass, I have also been switching over to acoustic guitar for a few songs. I recently bought a cheap, used acoustic/electric (an Ibanez AEL-20E) which has a piezo system built-in, for use on the acoustic numbers. (I found that, by shopping used, I could actually buy an entire acoustic electric guitar for less than it would cost to put a decent piezo system in my other acoustic guitar.) When I first got it, I thought that the Ibanez sounded like every other guitar that I’ve ever heard with a piezo system. Harsh and brittle on the high end, with exaggerated string noise. This seems to be endemic to the piezo technology, itself, and is not a condemnation of the Ibanez. I’ve heard Martins that were equipped with a piezo system which sounded pretty much the same.

After some experimenting, I was able to make it sound quite a bit better. While you can’t take the piezo sound out with equalization, finding an amplifier that matched the guitar did seem to improve things quite a bit. Direct into a PA didn’t sound very good. In fact, this seemed to shine a spotlight on the piezo-ness of the sound. I have one bass amp which is so tonally neutral (especially when bypassing the preamp and going direct into the FX return jack) that I use it like a mini-PA system. This is what I use to amplify keyboards and the various bass amp models in my SansAmp and Boss GT-6B, and is the first amp I turn to when I need a “natural,” uncolored tone. The Ibanez sounded absolutely terrible through that amp. I mean painfully bad. Maybe there was an impedance mismatch or something, but this just didn’t work AT ALL. The solution that I finally came up with, which is what I used at our gig last night, was to plug into an electric guitar amp, an all-tube 15 watt Traynor amp, which has a really nice, mellow clean channel. The Traynor seemed to take quite a bit of the edge off of the piezos. (I’m guessing that this is because of the even order harmonic thing that you get with tube amps.) Anyway, that’s what I’m doing now.

Right now, I’d say I’m about 85% satisfied with the tone I’m getting. I am fully aware of the problems inherent in trying to amplify an acoustic guitar in a live setting, and I do understand that a certain amount of compromise is always required in these situations. I doubt that I’ll ever reach 100% satisfaction with the tone. But, I think there’s still room for improvement, without laying out big bucks for a different guitar, or a dedicated acoustic guitar amp.

I know that there are processors out there which are designed to take the sound of an acoustic/electric, and make it sound more “natural” (i.e. more like a real acoustic guitar miked up in a room). Some examples are the Boss AD series (AD-3, AD-5, & AD-8), the Yamaha AG Magicstomp, and the new (and rather expensive) Fishman “Aura” system. I’ve done some research and read some reviews on these units at places like Harmony Central. However, I still don’t know if something like this would work for me.

So, my question is, does anybody have any experience with these types of processors? What were your impressions of these units? In other words, how well do these things work, in real world terms? Would they take away enough of the piezo sound that I could run the guitar directly into the processor, and then on into the PA, and be able to leave the amplifier at home? Although I have gotten pretty good results going through the amp, it sure seems silly to carry an electric guitar amp to an acoustic gig. Besides, I already have to haul one amp for my bass. I’d rather not have to carry a second one for the guitar.

Thanks,
 
I am quite a novice in the acoustic guitar arena, so take this for what its worth, but not too long ago a friend of mine and I were providing sound equipment for a friend of my parents' who had come in from New Orleans to perform at a local winery. She plays a bazouki and was providing her own vocal mic, so we were just providing the mixer and speakers (an older, higher end Fender live mixer and 2-way EVs with 15s and horns), and a DI box for the bazouki. I had brought my passive DI box and also my SansAmp Bass Driver just on a whim. Before we moved all of the stuff, we plugged his acoustic (a $600 Takamine) into the system and had him strum a few chords. I had him plug into the passive DI first and then the SansAmp, and the difference between the two was like night and day. The SansAmp sounded much smoother and fuller, without the high end harshness of the passive DI. It was a far more realistic sound.

To make a long story short, I'd recommend trying out the SansAmp, as you might be pleasantly surprised.
 
Adam P said:
To make a long story short, I'd recommend trying out the SansAmp, as you might be pleasantly surprised.
Thanks. That's an idea. I did plug the Ibanez into the SansAmp when I was experimenting with different sounds. It sounded pretty good, actually, but I just thought the Traynor sounded better. Of course, I should mention that the SansAmp that I have is NOT the Bass Driver floor pedal, but the PSA-1 rack-mount unit. I've also got a Lexi fx unit in the effects loop, to give me chorusing, reverb, and so on. While I thought the SansAmp sounded pretty good with the Ibanez guitar, I didn't really spend any time optimizing it for the acoustic guitar. I just basically plugged it in and went through the presets, looking mostly at the models of the clean channels of various electric guitar amps. (Well, O.K. I'll admit that I also tried it through the Marshall plexi models and even the Brian May "Wall 'o AC30s" patch, just for fun.)

There are no acoustic guitar amp models in the 49 factory presets, or any of the modified ones that I've programmed myself for bass or electric guitar. However, the thing is flexible enough that I should be able to program a reasonably good acoustic guitar amp model, myself, with a little experimentation.

Those two units are in my small fx rack, along with a dbx ProVocal. I really need to start carrying that rack to gigs, anyway, to process my live vocal mic. So, I probably will experiment with it some more, and see what it can do for acoustic guitar.

However, I would still be interested in hearing from those of you who have any of the acoustic processors that I mentioned in the original post. I'm still interested in finding out more about those.
 
Try this: Get a Boss GE7 EQ pedal (or something similar) and run your guitar into this, then straight into the effects return of your amp. Put a shallow smile on the eq pedal faders, and you've got a cheap acoustic amp. Plugging into the effects loop bypasses the eq on the preamp and goes straight to the power amp section.
 
Those Boss processors pretty much blow, sorry to any Boss people lurking here. I tried a bunch of them, as I use a fair amount of processing, but I couldn't even get a good basic sound to work with.
 
freshmattyp said:
Try this: Get a Boss GE7 EQ pedal (or something similar) and run your guitar into this, then straight into the effects return of your amp. Put a shallow smile on the eq pedal faders, and you've got a cheap acoustic amp.
So, you're saying that the main difference between an "acoustic guitar amp" and a clean electric guitar amp channel is that the electric guitar amp will have a little more midrange energy? That's useful to know. While I don't have an EQ pedal, I do have a spare 31 band rack unit (by Rane) that isn't being used at the moment. And, actually, I was thinking about patching that into the signal chain anyway, since I didn't feel like I had quite enough equalization control, even with the EQ on the guitar and on the amp, itself.

This will also come in handy when I do some more experimenting with the SansAmp PSA-1. I will be starting with a model of an electric guitar amp, and trying to modify it to sound better on acoustic guitar.

Thanks for the info! :)
 
easychair said:
Those Boss processors pretty much blow, sorry to any Boss people lurking here. I tried a bunch of them, as I use a fair amount of processing, but I couldn't even get a good basic sound to work with.
Thanks for the feedback. From what I've read, these units perform at least four functions - they serve as a direct box to change the impedance of the signal so you can jack it into a PA system more appropriately, they provide equalization, they provide modeling technology to artificially change the perceived size of the guitar body (and how far the modeled mic is from the guitar), and they also provide some effects (chorus and/or 'verb, depending on the model). Specifically, what did you dislike about them? Also, if I may ask, how did you demo the units? Did you run them through a PA system or an amp?
 
Bassman Brad said:
Thanks for the feedback. From what I've read, these units perform at least four functions - they serve as a direct box to change the impedance of the signal so you can jack it into a PA system more appropriately, they provide equalization, they provide modeling technology to artificially change the perceived size of the guitar body (and how far the modeled mic is from the guitar), and they also provide some effects (chorus and/or 'verb, depending on the model). Specifically, what did you dislike about them? Also, if I may ask, how did you demo the units? Did you run them through a PA system or an amp?

I have run them both through PAs and amps. I had better results with amps than PAs, and better results with electric guitar amps than acoustic ones.

I feel this is because of the decreased treble response of amps vs PAs, and electric amps vs. acoustic amps.

The less treble the better, basically. :p

The sound always seems tinny and cold to me, and just plain fake. Adding effects seemed to make things worse, as the signal into the effects was always the cold, thin sound of the guitar through the processor, as my reasoning goes. Adding effects seemed to make them sound even more metallic.

Electric guitar and amp modeling still takes quite a beating as far as quality, modeling an acoustic is orders of magnitude more complex.

Check them out for yourself, but that's what I found. Also, I haven't checked out the Yammie pieces, they may be better.
 
My experience has been that with the right buffer a transducer doesn't have that squawk and harsh ping to the sound that they get otherwise. I've found that a variety of pedal effects (just running through w/effect off) and pre's I've got laying around function well as buffers for the Dean Markley and Baggs transducers I've used.

Tim
 
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Cool deal. That's exactly what I'm trying to do - figure out a way to send the guitar direct without it sounding too "piezo-y." (However, after thinking about Mr. Lawler's post, as well as my own experiences with how much of that piezo sound will go away, if you just find the right unit to play it through, I'm starting to wonder how much of what I thought was the characteristic "quack" of piezos is actually the sound of the guitar's signal not being properly matched to the rest of the signal chain. Possibly an impedance mismatch?)

Anyway, thanks for the info!

Anybody ever get a chance to compare two or more of these types of units side by side?

What about noise levels? I've heard that the Boss units, in particular, can be a bit noisy. Anybody have a problem with this on any of the units mentioned?
 
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