Hello Troubadourians! August seems to be the month that brings out the “guitar geek” in everyone. A lot of you have asked me recently about how I get my acoustic guitar to sound like it does… like a guitar. Even though I covered the basics of my signal chain in my August column last year, I apparently didn’t go into enough detail for many of you. I’m pleased and humbled that you like my tone enough to ask about. I’ll do my best to explain the How, What, and particularly the Why of my acoustic rig. I’ll talk about my guitar, my pedals, and my philosophy of tone. As I’ve said in past columns, pretty much everything that we utilize to amplify our acoustic guitars adds their own tonality to the sound, sometimes to the point of obscuring the things that we recognize as uniquely “us” and making our guitars sound rather generic, and maybe even a little fake. When pickups and electronics are combined with acoustic guitars, the sound of the technology itself can often dominate the natural sound of your guitar.
Yes, I have a really great guitar, a Collings D2H, so, it’s got to be the guitar, right? Well, that’s always a good place to start but isn’t always a guarantee that your amplified tone will be great. Here’s a familiar story – you’ve decided that you’re ready for that high-end, boutique, or custom-built instrument. When you play that beauty live, you want it to sound as good as it does in your living room. So you put in a pickup, cross your fingers, plug in, and… your new guitar sounds pretty much like your old one did. So, it’s the pickup then? Well, no, not really. I have a really simple Fishman under-saddle pickup system in my guitar. In addition to the transducer under the saddle, there is a basic preamp with a volume control and treble and bass controls. I almost always have the volume set at 75%. I will sometimes back-off the bass a touch if the sound in the monitors is really boomy or bass-heavy and I might add pinch of treble to brighten the tone if my strings are fading, but 99% of the time they’re flat, meaning no boost or cut. The basic tone from the pickup system is pretty good at this point, but it’s still a piezo pickup and – for me at least – amplifies a little too much of the sound of everything in the guitar. Most of what we perceive as the tone of a guitar is the different frequencies reaching our ears at different times and blending into the tonalities unique to that instrument. In general, acoustic pickups capture all of the sound in a guitar, amplify it, and deliver it to our ears all at the same time. There isn’t any of that acoustic blending we’re accustomed to hearing and that’s why most pickups don’t sound natural.
Ah, I see… Then the secret is in the pedals, right? Well, sort of… My signal chain is pretty basic; it’s just a series of gain stages and tone controls that I use to take away the tonalities from the pickup that aren’t in my guitar’s natural tone. There isn’t any one thing on my pedalboard that gives me “that tone” that you’re hearing. Rather, I utilize a philosophy of “Addition by Subtraction” to achieve the sound I desire. First, I use a Fishman Aura pedal that has several digital models that replicate the frequency response of high quality studio microphones that are recognized as making guitars sound good – natural – and that record well. This pedal acts like a filter and I can blend the digitally modeled microphone with the basic sound of the piezo pickup and reduce much of its inherent harshness. (I resisted the urge to geek out and I didn’t look at the manual’s explanation of which setting represented which microphone. I simply set the output for a 50/50 blend of the filtered and un-filtered sounds and turned the selector knob until I found a tone that sounded like “me” and I haven’t touched it since). The next pedal is a MXR 10-band EQ. Its sole function is to selectively reduce the lower frequencies that contribute to body resonance and the high frequencies that contribute to noise. The “EQ curve” that works for me is tailored to my specific guitar. The body size and the type of the wood used in its construction contribute to the specific frequencies that I need to control. My rosewood dreadnaught will likely require a different curve than a guitar that is a different size and wood type. Because I play solos, I have the need to boost the level of my guitar’s output when I do so. I use a MXR dyna-comp compressor for this function. The compressor is set for minimal sustain and only enough boost to bring my single-note playing up to the level of my rhythm playing. I don’t use the compressor to “color” my tone; it’s only for temporarily increasing the level of the signal. If I were only playing rhythm guitar to accompany a singer I probably wouldn’t use it at all. The compressor aside, at this point in the signal path my amplified tone is “dialed-in” to sound essentially the same as my un-amplified guitar. But since all of the tone shaping has been subtractive, I need to bring my final overall level up somewhat so that I send a useable signal to the PA. For this I use a MXR micro amp which is just a level-matching amplifier that doesn’t “color” the tone at all. This “finished” signal is then split into two paths; one goes to a passive impedance transformer a.k.a. “Direct Input” (DI) or “direct box” which sends my guitar signal to the PA, and the other path goes to an onstage amplifier that I use only as a personal monitor. For those of you who must know, it’s a Fender Acoustasonic DSP 30. There are much better – and louder – acoustic amplifiers available than my little Fender, but it serves me okay.
But… no matter how much money you invest in your guitar, no matter what gear you ultimately play through, the essential element of any system or rig is YOU. Your own two hands determine the majority of your unique tone. Even if you were to play my guitar through my rig, you would still sound like you. And isn’t that what we’re all trying to do in the first place?
Need to know? Just ask… Charlie (firstname.lastname@example.org)