Acoustic Image Coda: Review

This is a review of the original Coda, introduced by Acoustic Image around the year 2000 or 2001, mostly written in 2001. Since then they have expanded their offerings, addressing most of the (minor) criticisms in this review while adding power and reducing weight. I've put a few new comments in [square brackets] to signify some of the changes that Acoustic Image has made.


I'm an acoustic and electric upright bass player who bought an Acoustic Image Coda combo amplifier. Though I'm no expert on this stuff, I like to think I have a pretty good ear and I thought people interested in this amp might want to hear my opinions. So here they are!

The instruments I've played through this amp include a Jensen electric upright bass with an RMC pickup and my old Czech or German flatback bass with, at various times, an Underwood pickup and a K&K Double Big Twin pickup, and Fishman Full Circle pickup. Often other musicians I play with will plug in as well; I've had good results with electronic keyboards, guitars and vocals.

I bought my Coda from Bob Gollihur, who's always been a pleasure to deal with.


I'm blown away by the Coda. It has a very clear, uncolored, natural sound. It's small and light, very easy to carry around with one hand (or shoulder strap with optional gig bag). It's got more inputs and outputs than you will need unless you're really kinky. It costs $1000 [in 2001], which is a lot, but it seems worth it.


It looks kind of like black R2D2. The controls are on top. It has a downfiring 10" woofer underneath, and front-firing 5" midrange and tweeter. Because of the omnidirectional downfiring woofer, this amp is more forgiving than many others in terms of placement in cramped quarters. But because the midrange and tweeter are front-firing (as they should be) it's still somewhat directional, if less so than most amps.

Some of the black plastic of which it's made is covered with black carpet. If I had a vote, I'd vote against the carpet because it says "scratching post" to cats [now fixed]. It does look good, though. The speaker grille is just flexible plastic; a swift kick and the coaxial midrange and tweeter would be toast [now fixed]. The tweeter, which practically touches the grille, seems especially in danger.

Otherwise the amp seems sturdy and well made. The controls, inputs, and outputs are well laid out and feel solid. It must have been a challenge to pack all that stuff in that relatively small space. Mounting them on top was a good decision given the amp's stature. The amp comes with a little gizmo that can angle it up if you are playing in close quarters [now built-in]. That supposedly reduces the floor coupling needed for the bass notes, but it still sounds great to me.

The power cord is a standard removable cord, so a damaged cord does not mean a repair job. It's also convenient: I leave one cord carefully snaked behind furniture in the room I usually play in, and carry another in the case.

The (optional $100) case is basically a tom-tom case. It's a nice case, well padded with both handle and shoulder strap, but it sure could use some pockets on the side and top for cords, music, and miscellaneous junk. Backpack straps would be another improvement.


The Coda has a very clear, uncolored, natural sound. Its frequency response is great all the way down to the fundamentals on my bass, and goes as high as any musician will need. It's more than loud enough for me, and I don't think I've gotten close to distortion. I'm told that this amp has plenty of oomph for a bassist in a big band. From personal experience with this amp I can only vouch for a dectet, but I have played in big bands, and I believe it.

The four-band EQ [now only three] is surprisingly more versatile than a three-band. I get a really nice bass sound by cutting a lot of the "brite" and boosting the midrange a bit. Having plenty of treble, but not much "brite", means I get a nice edgy sound but not too much finger noise.

Even though the stats claim that the amp goes up to 20kHz, there's very little hiss.

My one complaint about the sound is that it seems to be missing a little punch or tightness. At first I guessed it might have something to do with the downfiring woofer. But then I discovered that if I tune the notch filter (see below) to a particular note's fundamental, the amp does seem to have more punch around that note, even though there are still a few octaves of harmonics going through the woofer. So my guess is that the simple presence of the fundamental lowers the perceived punch. I have to say I like hearing that fundamental, and some lack of punch is a fair price!

Features [again, this refers to the Series I]

Acoustic Image calls it a two channel amp, but it's way more flexible than that would lead you to believe. The two nominal channels are a mic channel with XLR input and an instrument channel with two 1/4" inputs (high/low gain; the high gain input has two impedance choices). Each channel has four band EQ. In addition to the two nominal channels (three inputs), there are effects loops for each channel and a a stereo aux input (mixed down to mono). The mic input, both instrument inputs, both effects loops, and the aux input each have their own level controls. So if you're perverse you can use six inputs simultaneously, each with its own level control. The effects returns and aux input come in post-preamp, though, so instruments that require a preamp or EQ cannot use these inputs effectively. The point is not to use up all six inputs, of course, but rather that a small number of sources are likely to find a way to coexist nicely with this amp.

There's also a master level control and a sweepable notch filter to control feedback on the instrument channel. Unfortunately the notch filter cannot be disabled [now fixed] but it's not too hard to find a spot where it's not really in the way. Sometimes a room has a resonant frequency that you can tune the notch filter to. But it would have been nice to have an "off" position for the knob or if it could be tuned a little lower, completely out of the way.

You really don't need a preamp with the Coda, even with otherwise unaided piezo pickups. The high gain input has two impedance settings, and the high impedance setting is designed for piezos. My acoustic bass and my electric upright bass with RMC pickups both sound great plugged straight into the high gain input with high impedance setting. With my outboard RMC preamp, my EUB sounds good when plugged into the high gain input with low impedance, or into one of the effects returns.

For outputs, it has an XLR direct out, Speakon external speaker output, and 1/4" headphone jack. The headphone level is not affected by the master level control, so you can use the Coda as a headphone amp just by setting the master level at zero. You can also use the headphone as a monitor by leaving the master level up. There's no headphone level control; you have to control all the input levels to control the headphones. But this is usually no big deal if you only use one or two inputs. Given how many knobs, inputs, and outputs the thing already has, I can see why they decided against one more.

Coda vs. Contra

I also considered buying a Contra, which is $200 cheaper than the Coda. I haven't heard the Contra, but I assume that, when used as a bass amp, the Contra sounds almost as good as the Coda. My evidence for this is that when I turn off the Coda's tweeter to simulate the Contra's sound, the difference (mostly in attacks and finger noise) is audible but subtle: High freqs like finger noise sound cleaner and more accurate with the tweeter and more "electronic" without the tweeter. Even though I'm a bass player, I prefer to use the tweeter and cut the brite control as I described above to cut (but not eliminate) finger noise.

What sold me on the Coda over the Contra is its flexibility. In a small venue, a duo or trio can use a Coda by itself. The Contra doesn't have the inputs for this, and its lack of a tweeter means the higher instruments will suffer a little. If you mic your bass, you can mix your mic and pickup signals without a separate box. You can practice with a CD or MIDI file playing through the aux input, or plug in a CD player when you go on break. You can use it as a headphone amp or use the headphone out as a monitor. It makes a dynamite powered speaker system for a PC or portable stereo (just add CD player, laptop, or whatever), except of course that it's mono!

Acoustic Image

Acoustic Image is a great company to work with. It seems to be pretty much of a one person shop; every time I call or write, Rick Jones, the guy who founded AI and who designs the amps, answers. Rick is very responsive to questions, even stupid ones, and he answers in detail. I'm sure Rick would like to make money on Acoustic Image, but you can tell this is also a labor of love for him.

Acoustic Image has a 14 day, no questions asked return policy, which means that if you can't try one of their amps in a shop (my two local AI dealers near me never had any in stock because they got scooped up whenever they arrived) you can order one and send it back if you don't like it. I don't think you'll send it back.


I'm very happy I bought this amp. The sound, power, features, and size are balanced extremely well. If you are looking for a small, flexible, accurate, full-spectrum, powerful combo amp, the Coda will do nicely. I have not seen anything on the market that comes close.

Please like me! • Jon Dreyer • 781-696-2614 • 81 Baker Ave, Lexington MA 02421-6228 • email