Acoustic Research Stereo Remote Control

Prologue: The context for this review is that back in the 1980s, preamplifiers and integrated amplifiers with remote controls didn't exist. In early 1985 I borrowed a sample of Acoustic Research's Stereo Remote Control, which I believe was designed by Ken Kantor (later to find fame with NHT) and set it up in my bedroom. It drove a pair of powered loudspeakers with auto turn-on, and I very quickly grew to appreciate, not just the sound quality, but the convenience of being able to control the system from the comfort of my bed. So what did JGH think of the SRC?—John Atkinson

Now here's a cute and useful gadget. The Acoustic Research Stereo Remote Control allows you to perform the most often used system control functions/plus a few unusual ones, from anywhere in the listening room.

First of all, who needs a remote control anyway? In fact, most perfectionists could use it, because the best spot from which to judge, channel balance and reproduction scale (listening volume versus apparent recording distance) is from the middle of the listening area, which is usually not within reach of the appropriate preamp controls.

The SRC's central control module is a tiny box with a row of 5 LEDs which indicate the status of the device at any time. The only "control" on this is a button that selects Tape Play—a function that need not be remotely activated anyway because of the need to load and start the tape before playing it. The tiny hand-held remote controller has only four keys on it, but these are integrated to provide a total of 15 remote functions! Each side of each rectangular key performs a different function (eg, Volume Up, Volume Down, on one key), and several keys—perform secondary functions if you first press a Shift key.

At its full-volume setting, the SRC is a unity-gain device (provides no amplification). It may be connected between a preamp and power amp or to a preamp's tape loop or EPL (External Processor Loop) receptacles. The latter two possibilities are preferable in most cases, as the SRC has Tape loop connections to substitute for those on the main preamp when the SRC is installed.

The unit's switched AC outlet will handle up to 600 watts (5 amps), which rules out the use of most amplifiers with super-beefy power supplies having tens of thousands of microfarads of storage capacitance, as most of these draw far more than 5 amps on turn-on.

The volume and balance changes effected by the unit are not continuous, but occur in 1.5dB increments. On paper this may seem unduly coarse, but in practice it isn't. Frequency-response changes of less than ½dB over a large segment of the audio range are clearly audible because of the resulting change in tonality, but a 2dB change across the entire spectrum is barely audible, and 1dB is less so. And the 1.5dB channel-balance increments occur in one channel only (the one being attenuated), so the level difference between increments is 1.5dB rather than 3 (as would be the case if one went down by 1.5dB and the other up by 1.5dB).

Each time the Volume or Balance button is briefly pressed, the signal is incremented by one step. Holding that button down produces a continuing change at a rate of about one incremental step per second. For faster incrementing, you use the Shift mode.

The Shift function is actuated by pressing the On switch while the unit is already on, and then pressing the desired function button. Thus, Shift plus Volume Up causes volume incrementing at a rate of about one step per half second. Other Shift functions include Left-Channel Mono, Right-Channel Mono, Full Mute (sound completely off rather than attenuated by 20dB), restore to Center Balance, and Sleep Timer. The latter is a delayed turnoff that allows the system to play for 30 minutes before shutting itself off. This, obviously, is for the benefit of those who have extension speakers in their bedroom, or who sleep in their listening room.

The SRC is left plugged in at all times. (It draws only about 6 watts of power.) It stores all previous settings in memory and recalls them when next turned on (by the remote unit). If the unit is unplugged and plugged in again with the power amp on, it produces only a small harmless click and comes on with the Mute on and the Volume all the way down. The unit cannot damage speakers or amplifier unless improperly used (about which see below).

The manufacturer's frequency response and distortion figures on the SRC are astonishingly low, and though I have no means of verifying them, I can attest that the device affects virtually nothing in the sound when operated at or near full volume. At substantially reduced volume settings, the SRC produces what sounds like a very gradual, progressive increase in distortion, barely audible at the worst as a subtle fuzziness. The worst condition, of course, is with the SRC turned down by about 20dB or more and the main preamp's volume control cranked up to compensate for it. If the main volume is set for the loudest level you'll want when the SRC volume is full-up, the latter will rarely need to be turned down so far as to produce audible distortion. In fact, setting the main volume control too high can risk damage to your speakers or power amp, if the preamp's Monitor switch should accidentally be set to Source while playing loud material!

Under normal listening conditions, the only change in sound with the SRC in use may have been an extremely subtle diminution in depth, but I'm not at all sure it was doing even that. It is possible that with the next generation of audio electronics, having even greater resolution than the equipment I am now using (the Berning TF-10 and Conrad-Johnson PV-5), the SRC may cause a perceptible loss of detailing, but I can only speculate on that. As of now, everything considered (and price in particular), the sound quality from this device is quite extraordinary. There are very few $1500 preamplifiers that color the sound as little as the SRC does. And there has never been, to my knowledge, any active device as inexpensive as this that has introduced as little signal degradation.

My sample SRC introduced a very small amount of hum into the system when used between the preamp and one of the power amps we had on hand. This was low enough in level that with a typical high-quality, low-efficiency speaker system the hum was inaudible at distances of more than a foot from each speaker. This is probably well within the manufacturer's 95dB-below-l-volt spec and is totally negligible. A very high gain amplifier, exceedingly efficient speakers (like Klipschorns) or a 60Hz room resonance could conceivably exaggerate the hum to the point where it is barely audible from several feet away, but the likelihood of all three factors conspiring to produce a hum problem is virtually nil. And if you connect the device to your main preamp's Tape loop, hum will be totally inaudible under any circumstances.

My only real criticism of the SRC has nothing to do with its performance but with its indicator lights, which are so bright that they can be distracting in a dimly lit room. In darkness they will actually cast shadows on the opposite wall. It would be nice to be able to turn these off—all except the red Mute indicator, which should be conspicuous. You can dim the indicators by applying two layers of frosted "invisible" tape over the transparent front strip (making sure you leave a 1" space for the infrared pickup device located directly beneath the "reo" of the word "Stereo" on the front panel).

Summing Up
In short, this little gadget works superbly. And although it is intended for use in conjunction with a conventional preamplifier (or an integrated amplifier with an EPL or Tape Loop or removable preamp/power amp links), it could easily serve as the main control center for a simple system using only high-level sources. For example, the Main input could be for a CD player, EPL for a tuner, and Tape for a tape deck.

The device does not foul CD sound, as do many much more expensive conventional preamplifiers.

Couple the SRCC with one of those inexpensive phono units having its own in board RIAA preamp, instead of one of the other high-level sources, and you could have a complete remote-controlled system of considerable quality.

At the price, this is a steal! Very highly recommended.

Acoustic Research (a division of Voxx international)
3502 Woodview Trace
Indianapolis, IN 46268
(844) 353-1307

Anton's picture

This would be a great addition to many current preamps with no remote volume feature or a tape loop!

tonykaz's picture

One sold for $179 + $24 for shipping from a Providence RI Used Equip. outfit.

Tony in Venice Florida

tonykaz's picture

Where is the "we" in all the commenting on this remote device ?

I don't recall Holt referring to his reviewing being done by a single person, he seemed like he was always referring to a vaguely defined group of We. Decades later I concluded Holt was using the Royal "We" descriptive term, the same descriptives used by British Sailers who refer to themselves in a plural sense. ( the sailor and his Ship )

In 1985 I was part of a Reviewing Group of Audiophiles, we evaluated gear as a booze drinking group of ( like minded ? ) debaters. I purchased Product Lines that our group collectively liked but buying and paying was always a singular action.

In 1985 I was not reading Stereophile, I was still a HFN&RR & Audio Mag. reader. Back then I ( we ) was/were selling TAS Mag over the counter at Esoteric Audio but doubting the validity of it's integrity. I still don't read TAS.

I advertised in Audio Magazine

Tony in Venice Florida

Kal Rubinson's picture

Some years back, I was looking for one of these and my (soon-to-be) wife found one for me. I replaced the opamps, changed the filter caps and used it as a preamp in my office system.

Cute design: It used the precision resistors in a ladder DAC as the attenuator.