The Ruppert Musical Instruments Acouswitch IQ DI is a two-channel acoustic DI and preamp pedal built in Germany. The maker's manual describes it as several tools in one unit: "It is an A/B-input switcher, a high-end preamp, a clean booster, a parametric EQ, an FX looper and a D.I. box." Channel A carries a high-end preamp and a 3-band EQ designed specifically for acoustic instruments, with bass, semiparametric mids and treble controls1.
Lehle GmbH lists the RMI Acouswitch IQ DI as discontinued on its product page2. The pedal is no longer in production, so players looking for one are into the secondhand market.
What it does for an acoustic player
The Acouswitch IQ DI is aimed at the working acoustic player who needs to switch between two instruments, shape each signal, run effects, and hand the mixing desk a clean DI feed, all from one floor unit. Premier Guitar's 2021 review summed up its scope: "The German-built Acouswitch IQ DI from Ruppert Musical Instruments falls into the very good category." The reviewer also praised the build: "It's built as solid as an old Mercedes"3.
Despite the amount of circuitry inside, the enclosure stays compact. Premier Guitar noted it is not much wider or thicker than a paperback, with the knobs recessed into a raised section3.
The controls
Premier Guitar counted the front panel at nine knobs, three footswitches and two mini toggles, alongside the eight I/Os3.
Footswitches1:
- A/B: toggles between input INST A and input INST B, and between channel A and channel B
- MIX LOOP/BOOST: the loop switch doubles as a boost when no loop is engaged3
- MUTE: mutes the LINE OUT and D.I. OUT for quiet tuning or stand-by
| Control | What it does |
|---|---|
| Bass / semiparametric mids / treble | 3-band EQ on channel A, designed for acoustic instruments |
| MF (mid frequency) | Isolates the desired frequency |
| ML (mid level) | Boosts the selected mid frequency |
| Body contour | Notch filter, 45 to 500 Hz, against feedback or as a low boost |
| Mix | Sets the blend of effected signal in the switchable loop |
| PAD | Attenuates the output to match a mixing desk's microphone input |
| PRE/POST | Takes the EQ and effect loops out of the D.I. signal path |
| MIX switch | Chooses between switching inputs A and B or running them parallel |
| PHASE | Inverts the phase of the Mix Loop return signals if needed |
On the semiparametric mids, Premier Guitar's reviewer found it "an entirely painless process of isolating the desired frequency with the MF (mid frequency) control and boosting" it with the ML control3.
The body contour control
The body contour control is the pedal's feedback tool. Lehle describes it as, on one hand, a narrow notch filter to reduce feedback with a frequency range of 45 Hz to 500 Hz, and on the other hand a broad low to low-mid boost2. Premier Guitar called it "effectively a notch filter that works within the 45 to 500 Hz range" and found it pretty effective against feedback and for bolstering the low end3.
Effects loop and DI routing
The pedal carries a serial effects loop and a switchable effects loop, and the loop switch doubles as a boost when you have nothing in the loop3. The manual adds a Mix Loop with a PHASE switch to invert the return signal's phase if needed1. The PRE/POST button takes the EQ and the effect loops out of the D.I. signal path, so the feed to the desk can be kept clean of your pedalboard1. A separate additional output is provided for a tuner2.
Two instruments at once
With two channels for separate instruments3 and a MIX switch that lets you run input A and input B in parallel, simultaneously, rather than switching between them1, the Acouswitch IQ DI can carry two instruments into one signal chain. That puts it in the company of other two-channel acoustic preamps such as the Radial Tonebone PZ-Pre and the Grace Design MOXi, though those pages cover their own features. For more in this territory, see Acoustic Pedals and Preamp Pedals.
In the box
The package includes the pedal, an optimized power supply connector, 4 mounting plates, the user manual and a gig bag1.
Videos
Premier Guitar
Jacques channel
Jacques channel
Questions
Is the Ruppert Acouswitch IQ DI still made?
No. Lehle GmbH, the company that handled the RMI product line, lists the Acouswitch IQ DI as discontinued on its product page. Units are therefore only available secondhand or from remaining stock, and the manual and product information remain available online for owners.
Where is the Acouswitch IQ DI made?
Germany. The manual from Ruppert Musical Instruments states that the Acouswitch IQ DI is manufactured, assembled and tested in Germany, and Premier Guitar's review likewise described it as German-built.
What does the body contour control do on the Acouswitch IQ DI?
It is effectively a notch filter working within the 45 to 500 Hz range. Lehle describes it as a narrow notch filter to reduce feedback, which can also act as a broad low to low-mid boost. Premier Guitar's reviewer found it pretty effective in use.
Does the Acouswitch IQ DI have an effects loop?
Yes. Premier Guitar noted both a serial effects loop and a switchable effects loop, whose switch doubles as a boost. The manual also describes a Mix Loop with a phase switch to invert the return signal if needed, and a mix control that sets the blend of effected signal.
Can you run two instruments through the Acouswitch IQ DI at once?
Yes. The pedal has two channels for separate instruments, and a MIX switch determines whether you switch between input A and input B or run them parallel, meaning simultaneously. The A/B footswitch toggles between the two inputs and channels.
Sources (3)
- EN.indd, Ruppert Musical Instruments, 2023
- RMI ACOUSWITCH IQ DI (DISCONTINUED), Lehle GmbH
- Ruppert Musical Instruments Acouswitch IQ DI Review, Premier Guitar, 2013-04-15
