Dr. Richard Jones 1947-2023

I am very sad to report the passing of Rick Jones, founder of Acoustic Image, on April 17, 2023. He and I developed a rapport over the past 20+ years, and his commitment to service and support was legendary. Operations at AI have been suspended.

I will provide repair service for Acoustic Image amps. Stay tuned for info.

GH Services is an authorized Acoustic Image Dealer. We provide competitive pricing on Acoustic Image products in Canada and the United States. Acoustic Image amplifiers are hand-made in Raleigh, North Carolina, U.S.A.

Acoustic Image DoubleShot combo with extra cab
Acoustic Image "Double Double" combo

GH Services is located in the Niagara Region of Canada, near Toronto and the Canada-U.S. border. Owner Greg Holmes is a long-time bass player and studio musician, ready and able to help you with any questions you have. More about GH Services here.

First batch of Series III equipment, in 2006
Acoustic Image has introduced some cool new
Series 4 plus models!
Please see the price list below for a summary.
Or scroll down for details...

High technology. Higher fidelity. For all instruments.

What's so unique about Acoustic Image?

Because of the sound quality and the small size, an Acoustic Image amplifier virtually disappears on stage, leaving the sound of the instrument being amplified, only louder. The amp is popular with Jazz guitar players and bassists, as well as horn players and vocalists. We use this amp as the reference amplifier for the BassLab instruments.

This is also an excellent amplifier for The Chapman Stick® since it reproduces the full range with sparkling clarity, and it has the two inputs for the Stick's stereo outputs. With a touch of the built-in reverb (on the "R" models), the Stick amplification is complete.

What Are The S4plus Models?

The S4plus models all use the Clarus head (which is a preamp combined with a power amp) with varying speaker cabinets.

Clarus S4plus
Clarus S4plus
Coda S4plus
Coda S4plus
Corus S4plus
Corus S4plus
Clarus SL-2 / DoubleShot combo
Clarus SL-2 / DoubleShot combo

The differences between the S4plus and Series 4 preamps are noted.

  • Two identical channels that can be mixed to one mono output, or output as separate (stereo) channels. Per channel features:
    • Separately buffered XLR and 1/4 inch inputs — replaces combo jack in Series 4
    • Full 48V phantom power (switchable) for XLR inputs
    • Switchable 10 dB gain boost for low output mics
    • -6 dB front end gain option (user selectable with circuit board jumper) — new feature
    • Input level and master level controls
    • 4 band tone control section (low, low mid, hi mid, high) — replaces 3 band controls in Series 4
    • Switchable phase reverse
      • Can be converted to speaker emulation filter (user selectable with circuit board jumper) — new feature
    • Selectable and sweepable low cut filter (150 Hz and below) — more precise filter than in Series 4
    • Effects loop with send and return
      • Return can be used an aux input
      • Send can be used as a tuner output
    • Selectable effects with wet/dry mix control and variable rate control — new programs, variable rate control is a new feature
      • Reverb with variable decay time (room to hall)
      • Delay with variable delay time
      • Delay/Reverb with variable delay time
    • All selector switches are illuminated when on to give instant configuration information — new feature
  • Direct out with pre/post EQ selection, switchable 10 dB pad and selectable ground lift — 10 dB pad is a new feature
  • Mono or stereo 1/4 inch output (user selectable with circuit board jumper) — new feature
  • Headphone output (1/8 inch) — the 1/8 inch jack replaces a 1/4 inch jack in Series 4
  • Switchable limiter
  • Simulated stereo effects — pseudo stereo (one input---simulated stereo output) — new feature
    • Requires a second powered cabinet
  • Exceptional high fidelity performance
    • 20 Hz to 20 kHz +/- 0.5 dB frequency response
    • Signal to noise ratio greater than 110 dB at direct out — 15 dB better than Series 4
    • Low output distortion, high input clipping level due to use of split power supply — 10 dB more headroom than Series 4
    • Compatible with all instruments

As you can see, many new features are introduced in S4plus and the performance is markedly improved.

The Amplifiers

The Clarus (400 Watts into 4 Ohms) and Focus (800 Watts into 4 Ohms) models combine a one channel preamp or two channel preamp with digital effects, and a switch mode power amplifier in a compact book-sized package that weighs about 2 kilograms (4 pounds). It provides transparent, powerful, and accurate sound reproduction across the full frequency spectrum for acoustic and electric instruments.

Acoustic Image Series III Focus 2R and Clarus 1 amps
Acoustic Image Series III Focus 2R and Clarus 1 amps

Each channel of the preamp section has a combo mic/line input connector, 3-band equalization, a parallel effects loop with return level control, and a selectable notch or low cut filter which is very effective for feedback or "boominess" elimination. There's also a master balanced direct out with ground lift to allow connection to a mixing board for PA augmentation or recording.

The switch mode power amp section drives loads as low as 2 Ohms, and has a switch for dual voltage operation (115/230V, 50/60 Hz) and a detachable power cord.

Unlike other solid state amps, the Clarus and Focus have a distinct, warm sound, more like a tube amp, and they are not "voiced" like many electronic instrument amps -- the frequency response is almost "ruler flat". The EQ is sufficient to overcome room acoustics or to shape your sound without adding noise to the signal, and the optional reverb adds fullness and presence. The amps were not designed to be driven hard to create distortion in the amp, but effects pedals can be used at the input or in the effects loop, and the fidelity of the amp lets the effect shine through.

Acoustic Image Series III Coda R combo
Acoustic Image Series III Coda R combo

The Combos

The Contra (1 channel) and Coda R (2 channel with effects) are compact and powerful combo amplifiers for acoustic and electric instruments. Combining a 3-way speaker system with the Clarus amplifier in a compact 8 kilogram (20 pound) package, many noted players believe they achieve the world's best acoustic sound for bass, guitar, and keyboards.

In this context, "acoustic" means a comfortable volume level where the combo is effectively invisible, providing amplification without coloration.

The combos have a flat frequency response coupled with an extended, tight, well-controlled bass sound and clarity of reproduction. Omnidirectional output of frequencies below 800 Hz allows instruments amplified by the combos to be easily heard by other musicians across the bandstand.

The Series III combos have are the result of extensive redesign into a lighter and more compact format, The electronics, speakers, and sound are the same are previous models.

Using the lifter to tilt the amp
Using the lifter to tilt the cabinet

In order to have a compact enclosure while maintaining accurate reproduction across a broad spectrum of frequencies, a compromise was made in the absolute volume at which the combos and EX cabinet can play at the lowest frequencies. Generally, if the EQ is flat, and aggressive low notes on an electric bass guitar are played, the cabinets can handle the low frequencies up to the point where the preamp "Level" control and the "Master" control are at their 12-o'clock positions (about half way up).

We've found that we set both controls to their 10-o'clock positions for most restaurants and small clubs, leaving plenty of headroom. This is with the combo providing amplification for both guitar and bass simultaneously, and sometimes a microphone. A truly portable PA!

For some venues, a Contra EX extension cabinet can be added for more coverage, but in a higher volume situation you'll want a larger extension cabinet or augmentation by a house PA system. To peel the paint off the walls, we like to use the Acoustic Image amps with AccuGroove cabinets. The fidelity of this combination is amazing. The amps also work very well with the popular speaker cabinets (twin 15 bass cabinets, quad 10s, and so on) that some venues have on hand as "house cabinets".

A built-in lifter mechanism under the front of the combos and EX cabinet allows them to be tilted to better direct sound to the player's listening position. An optional padded gig bag with shoulder strap makes the combos convenient for the travelling musician.


I am blown away by what I am hearing!!! I have heard a few bass players through Acoustic Image combo amps and have always been impressed. I had no idea that they could work so well for Keys. This tiny Coda R amp with Contra EX cabinet seems to allow me a dynamic range unlike any keyboard amp I have played through. I can play gently and still project clearly through the room - not simply softer!! There is also this incredible 3-D quality to the sound projection which actually seems to give my piano samples the most realistic quality I have yet to experience on a keyboard. Thanks!!! · Sean M., B.C.

All my guitars sound smooth as h... through the Corus EX and, like they say, with a kind of 3D presence. We played a nylon Taylor (piezo), a Gitane gypsy jazz box (Schatten), and an Eastman archtop (oval hole, non-cutaway, with a Shadow sound hole magnetic p/u). · Dallas S., B.C.

I just opened and plugged in and I am already floored. And the weight... I don't understand how they can take a great amp, double the power and half the weight without compromising anything. Thanks a lot. · Ninn L., Quebec

I'm totally impressed with the natural sound of the instrument that the amp produces. It was well worth the wait. · Bryan D., Ontario

The amp works a treat. It has fabulous response to my Underwood pickup and the two filter levels work very well to shape the sound. I was playing on a low riser hollow stage Saturday night and the ability to cut out the boomy bottom made the whole difference for my sound. Other guys in the band are also saying that it is the first time outside of rehearsal when they've really been able to hear the bass clearly. Thanks again for everything. · James L., British Columbia

I just received and tried the Coda R and I love it. It's a fantastic piece of equipment. Archtop guitars just sing on it with deep and mellow sound to crisp or fat bass sound, always crystal clear sound, no matter the settings. Pushing the EQ does good results no matter what extreme you try. I am extremely pleased with the amp, the waiting was worth it! Thanks for your kind services. · Claude L., Quebec

Well, I just thought I'd let you know that the Contra is an unequivocal hit! I've played a few small room gigs and the other players have all commented on how big and how natural it sounds... much better for those rooms than my Eden rig. · Michael L.,  Nova Scotia

The amp arrived yesterday safe and sound, we are happy. Thanks again for appreciating our situation and responding so swiftly! · Lyndon G., Australia

We are now full blown into Jazz Fest and the feeding frenzy is on. So far I have had it at approximately fourteen or fifteen shows at 7 different venues, more than one time already at the weekly shows! The amp is awesome and I am glad I went with the Coda R because already vocalists in the trios are preferring to use my mic channel. · Mark P., Quebec

They delivered the amp directly to my apartment on Sunday at 12:30 p.m. I was expecting it Monday or Tuesday. The amp looks great but more importantly sounds great with the Azola Bugbass. I'm really happy with it. Thanks again for all your help. I will definitely recommend you to others. · Mike E., Ontario

Configurations and Prices

Order now! Contact us at ghservices.com@gmail.com or call our toll-free order line 1-866-666-7858.

The available configurations include the amplifier alone or in combination with a cabinet, in single channel or dual channel, both with effects. The following table shows the possibilities, with prices in Canadian dollars. We also sell directly to American locations - contact us for prices.

Free shipping throughout Canada and the U.S. for amps, combos, and cabinets!

Model Description Type Output Chan. FX US$ List* Your Price*  
606 IA Clarus SL S4plus
1ch 600W integrated amp
amp only 600w/4ohm 1 no US$ 629 Not available
607 IA Clarus SL-R S4plus
1ch 600W integrated amp with effects
amp only 600w/4ohm 1 yes US$ 749 Not available
608 IA Clarus SL-2 S4plus
2ch 600W integrated amp
amp only 600w/4ohm 2 no US$ 789 Not available
601 IA Clarus 2 S4plus
10"x8"x3.5", 3 lbs.
amp only 600w/4ohm 2 yes US$ 1029 Not available
* Prices subject to change due to currency exchange rate fluctuations, import fees, and other factors.
Model Description Type Input Chan. FX US$ List* Your Price*  
611 EX Coda
Speaker Cabinet - 1x10" speakers plus 1x5" mid
10" High, 12" Diameter, 13 lbs.
cabinet onlyrated
-- US$ 549 Not available
680 EX UpShot
Speaker Cabinet
6" High, 11" Diameter, 11 lbs.
cabinet onlyrated
-- US$ 429 Not available
690 EX DoubleShot
Speaker Cabinet - 2x10" speakers plus 1x5" mid
11" Wide, 12" Diameter, 15 lbs.
cabinet onlyrated
-- US$ 719 Not available
* Prices subject to change due to currency exchange rate fluctuations, import fees, and other factors.

Any combination of AMP and CAB above. Includes mounting bracket for Coda and UpShot cabs

* Prices subject to change due to currency exchange rate fluctuations, import fees, and other factors.

All amps (heads) come with a padded gig bag.

Acoustic Image products have a five year warranty. The warranty does not cover items that have been obviously damaged through misuse. Details can be found in the manual.

Order now! Contact us at ghservices.com@gmail.com or call our toll-free order line 1-866-666-7858.

No sales tax for American orders. GST/HST will be added for sales in Canada, and PST for Ontario. Preferred payment methods are, in order: e-mail money transfer (INTERAC), bank wire transfer, certified cheque, money order, PayPal (+3%), Visa (+4%), MasterCard (+4%). Credit card payments for non-Canadian customers are in CA$ with exchange rates chosen by the credit card companies, resulting in minor variations from the prices given here. It is usually possible to use PayPal even if you don't have a PayPal account.

Features and Specs

Features for the Clarus and Focus models

Neutrik Speakon speaker connector
Neutrik Speakon speaker connector

Features for the Contra and Coda Combos

All of the feature of the Clarus, plus:

Technical Specifications

Frequency Response20 Hz - 20 kHz ± .5dB
Distortion<0.5% full output, <0.01% typical
Hum and Noise-85 dB or better
AC Power115V/60Hz, 230/50Hz, switchable
Size, amp10" x 9" x 2.5"
Size, cabinet12" height x 15" diameter
Weight, amp2 to 3 kilograms (4 to 6 pounds)
Weight, cabinet8 kilograms (20 pounds)
Mic Input600 Ohm balanced, XLR connector
Phantom Power47 volts, on/off switch with LED indicator
Instrument Input1 MOhm impedance, 1/4" jack
Direct Out+4 dB, balanced, XLR connector, ground lift, pre/post EQ
Effects LoopParallel type, 1/4" jack w/ return level control
Bass ControlShelving type, ±15 dB @ 60 Hz
Mid Control±15 dB @ 650 kHz
Treble ControlShelving type, ±25 dB @ 10 kHz
Notch Filter-18 dB sweepable from 30 to 400 Hz
High Pass Filter-12 dB/octave sweepable from 30 to 400 Hz
TypeDigital with 6 presets and level control
Reverb Presets3 Reverb (Hall, Room, Plate), Delay, Ambient Chorus, Flange
Power Amp
TopologyClass D (PWM)
Switching Frequency230 kHz
Output Power (Clarus)>400 Watts, >500 Watts with 4 Ohm ext. cab, RMS continuous
Output Power (Focus)>800 Watts, RMS continuous
Minimum Load2 Ohm
Output Connectors1 (combos) or 2 parallel (amps) Neutrik Speakon type (pole 1), 4 Ohm min.
Speaker Components in Contra, Coda, Corus, and EX
Frequency Response30 Hz - 20 kHz (40 Hz - 16 kHz ± 3 dB)
50 Hz - 20 kHz (60 Hz - 16 kHz ± 3 dB) Corus
Impedance4 Ohms
Max Power300 Watts
Max SPL>112 dB @ 1 m
Woofer10 inch, downfiring, 30 Hz - 800 Hz
Midrange5 inch, forward firing, 500 Hz - 10 kHz
Tweeter1 inch forward firing, 8 kHz - 20 kHz, with on/off switch
CrossoverPassive, alignment corrected
Available AccessoriesExtension speaker (Model 510 EX), padded gig bag with shoulder strap,
"twist lock" (Speakon) to "twist lock", and "twist lock" to 1/4 inch speaker cables.

Controls and Connections

Clarus S4plus front panel
Clarus S4plus front panel

The rear panel is shown for the Clarus head and for the head docked in a Coda or Corus combo.

Clarus S4plus back panel
Clarus S4plus back panel
Clarus S4plus docked back panel
Clarus S4plus docked back panel

For all enquiries, contact ghservices.com@gmail.com.