Coleman Audio SR5.1 Surround Level controller and a/b 5.1 switcher

In this age of the over-the-top feature set on just about all things audio, manufactures seem to tack on just about anything either because they can or to prepare for the inevitable unique application. It’s called “feature creep” in electronic engineering, and it’s as insidious as milk spoiling when you leave it out of the fridge too long. Thanks to digital technology, deep menus, and multi-function selection switches, one usually has to be prepared to read the manual for a bit before you start the occasionally arduous process of interfacing a new device. Sometimes I long for the good old analog days when just about any link in the audio chain did one, and only one, thing, but it did it very well.

Coleman Audio apparently subscribes to that line of reasoning as well, as evidenced by their SR5.1
surround level controller and A/B 5.1 switcher, two devices that are supremely elegant in their simple-yet-effective functionality.

The Details
The SR5.1 is a 1U 19-inch rack-mountable 5.1 surround controller that stands out from the competition in that it’s entirely analog, with the system level control centered around a precise six-element stepped attenuator that tracks to .05 dB throughout its range. The front panel has just the aforementioned Level Control and an individual Mute switch for each of the six channels (unlike many other controllers, it’s only a 6-channel device). On the rear panel, there are six balanced inputs and outputs, all on XLR connectors (yes!!). That’s it. Plain and simple. If you want to trim the individual channel levels, there are internal trim pots to fine-tune the output level of each channel.

The A/B 5.1 switcher is designed to be used as either a simple selector between two 5.1 speaker systems or used to select between two different input sources to feed a single 5.1 speaker system. Once again, the box is 1U, 19-inch rack-mountable with the front panel containing just a single push-button In/Out selector switch. The rear panel contains three sets of six 1/4-inch TRS jacks plus a mini jack for remote switching.

The idea here is that you can not only easily switch between two sets of 5.1 speaker systems being fed from one source, but you can also use it to switch between, say, the output of a console or DAW and maybe a DVD player into the just one 5.1 system, too.

This system is clean as whistle because it’s a passive unit with all switching done with relays. There are no electronics at all in the audio signal path.

The accompanying manual for both units is a small, four-page fold-over that’s short and to the point. There’s not a big story to tell here, so you get just what you need to supplement the intuitive operational nature of the products.

In Use
Both units do exactly what they’re supposed to do, and do it well. Thanks to its minimalist signal path, the SR5.1 sounds great, revealing sonic faults that my usual system had veiled. It’s clean, precise, and (dare I use the word) audiophile in every sense of the word.

The only slight negative might be the fact that to level calibrate the system you have to open up the top and adjust the internal trimmers. This isn’t a problem in a system that’s not prone to change or if you can adjust the levels at the speakers, but it could be a bit of a pain if you change speakers or placement frequently.

The A/B 5.1 is one of those handy devices that will always find a place in a 5.1 studio. It’s sonically transparent and, thanks to its dual use, abundantly functional in everyday surround studio life.

Both of these boxes come at the right time in the surround business. There’s certainly a need for simple, yet functional devices that do their jobs extremely well.

PRICE: The Coleman Audio SR5.1 Surround Level Controller has an MSRP of $875 and the A/B 5.1 Switcher retails at $455.

Surround Professional Magazine