Surround Monitor Controllers

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Bobby Owsinski reviews two of the latest outboard controllers in part one of a two-part series.

It�s funny, but at this point along the time span of multichannel audio I didn�t expect that monitor controllers would still be an issue. But until fully functional multichannel monitor controllers become a standard feature on every new console and workstation, and people stop using old workhorse analog consoles, outboard surround monitor controllers will be more necessary more than ever. And the good news is that there�s a whole new crop of them and they�re getting better. This issue, we�ll take a look at two of them, the TASCAM DS-M7.1 and the EMM Labs Switchmaster Quartet, while next issue we�ll look at three more.

The EMM Labs Switchmaster Quartet

EMM Labs� Ed Meitner has amassed a reputation as an audio designer beyond reproach, with his DSD converters being the centerpoint of Sony�s Sonoma workstation. An outgrowth from Sony�s SACD project, the Switchmaster Quartet controller came in to being when Sony approached Ed about building an extremely transparent and high-quality controller for their demos. Never intended to be a releasable product, the Quartet nonetheless became one after a number of engineers working on SACD projects began to demand the units during mixing.

The EMM Labs Switchmaster Quartet is a 6-channel monitor control center that makes up for somewhat limited features (as compared to others on the market) with elegant simplicity and high sonic standards. The complete system consists of the main unit and a wired remote with all user controls and displays on the remote. The remote draws its power from the main unit.

The unit itself has four sets of multichannel inputs (six inputs per set) on the front panel of the main unit. Two of these sets are either balanced or unbalanced (via a small toggle switch) on XLR connectors. A third set is either balanced or unbalanced with XLR and RCA connectors, and the last set is unbalanced on RCA connectors only. The outputs of the Quartet are on the rear side of the main unit and consist of balanced XLRs and unbalanced RCAs, both of which are buffered for simultaneous operation. The back panel also contains power, MIDI, and remote unit connectors. A DIP switch set is placed on the back panel to set some operational preferences.

The remote consists of a large volume knob with a display that reads from 0 (full attenuation) to 110 (maximum level), along with buttons for system mute, four buttons to select the different sets of inputs, template recall and save, and channel trim controls. Each of these buttons has an associated LED beside it to indicate the button is operational. In addition, there are two buttons on the rear of the unit; a black �Shift� button and a red �Reset� button.

The trim control enables the user to precisely control the level of each channel with a resolution of either .25 or .5 dB, depending upon the DIP switch setting.

Template Load mode allows for the selection of one of six stored templates. Each template saves which input was selected, as well as the master volume, level trim, and mute settings. The system also remembers which template was last saved and restores that setting during power up.

Even though the Mute button is a master system mute, it can also be selected to become a Soft Mute that acts more like a dim mode in that it attenuates the master volume by 26 dB rather than muting the system completely. This feature is enabled by a DIP switch on the rear panel of the main unit as well.

The Specs
As you would expect, the specs are excellent with less than .01% THD and better than �80 dB crosstalk and less tan 110 dB SNR. In addition, the system has 9 dB of additional gain (most controllers are unity) with a maximum output of 26 dBu (lots of headroom, just like in the old days).

In Use
Boy, does this thing sound good! Or rather, it allows everything else to sound as good as it can. To say the least, I was astonished at the sound of the Quartet. As soon as it was connected, the monitor system came alive in a way I�d not heard (and I thought it sounded really good before). Everything was now bigger, fatter, and much more euphonic. Plus, I love the fact that it has XLRs rather than DB25s and RCAs for DVD playback.

The Quartet is generally easy to use, but there are a couple of small quirks that I found in the system. First is the placement of the Shift button, which, by being on the rear panel of the remote, is a little inconvenient, but really not that big an issue. On the unit that I tried, the one thing that did really bug me was the fact that you couldn�t trim a speaker channel level while in solo. This made monitor system calibration take a lot longer than it should, since the only work-around was to unplug the other five speakers from the controller and trim each one individually. After a brief conversation with Ed Meitner, this has subsequently been changed, and all units can now be updated so that trim will work in solo mode.

It should be noted that Meitner stated repeatedly that the Quartet was never intended to be a commercial product, so many features and conveniences were purposely left out. With the general acceptance and increased demand for the unit, an updated version is said to be in the works with a few more bells and whistles.

Price and Contact
The EMM Labs Switchmaster Quartet is one great box! It�s simple to use and sounds so clean you won�t believe it. At an MSRP of $3750 it�s not the least expensive controller on the market, but it�s certainly one of the best sounding. Highly recommended!

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TASCAM DS-M7.1 Surround Controller

While most manufacturers have maintained more or less the same mindset when designing a surround controller, TASCAM has chosen an innovative approach that utilizes the digital domain instead of analog. As a result, their DS-M7.1 surround controller fits a market niche previously unaddressed.

Designed especially for digital consoles or DAWs, the TASCAM DS-M7.1 not only adds multi-speaker monitoring control, but duplicates the output busses so that the signal can be routed to both a stem recorder and multiple amplifier/speaker combinations at the same time. This is a boon to systems that are limited to only eight output busses.

The DS-M7.1 supports all popular surround formats from LCRS, 5.1 and 6.1 to 7.1, as well as sample rates of 44.1k, 48k, 88.2k, 96k, and pull up/down operation via an external master clock. The unit has a variety of features, including bass management, standard 8-channel TDIF, AES/EBU and ADAT connections for a stem recorder, flexible downmixing, a built-in pink noise generator for monitor calibration, individual channel Mute/Solo and delay compensation, and standard monitoring controls like adjustable dim and alternate speakers.

The front panel is somewhat unique in that it detaches from the main unit to become a remote. Only the Power switch and the 9-pin DIN remote connector remain on the front of the main unit (an identical 9-pin DIN is located on the rear panel as well). The remote has a relatively short cable, but it can be extended with a standard 9-pin cable found at most any computer store. For very long extensions (more than 20 ft.), TASCAM offers a special cable as power for the front panel goes down this connection, so the cable tolerances must be very high.

The selector buttons on the remote are well laid out and labeled, and are supplemented with a backlit 20×4 alphanumeric display that shows the parameters and settings of the unit. Beneath the display are five buttons to select system preferences and a Shift key, which enables alternate functions of most of the buttons on the remote. These buttons allow you to select input and output assignments, channel level trim and delay, and downmix, bass management, and test parameters. The system buttons are supplemented with a rotary Value encoder to set the values shown on the display, and two cursor keys to navigate between the parameters shown on the display.

In the center of the remote lie nine Mute Control keys and indicators. These correspond to the channels of the different surround formats supported by the DS-M7.1. When a surround format is selected, the indicators of those channels that are valid for the format are lit. For example, if 5.1 is selected, the L, C, R, LS, RS, and LFE indicators are lit. The keys act as monitor mute keys or solo keys, depending on the status of a Solo/Mute key, and are also used for selecting channels when setting up the relative levels of the channels.

Just to the right is an SPL Reference indicator and Level control used to set and view the SPL level output by the DS-M7.1 when it is properly calibrated.

The remote also has a number of other useful function keys. The ALT SPK key selects speakers connected to the LC and RC channels. When in surround mode, pressing this key automatically performs a Left/Right downmix to the LC and RC channels. Solo/Mute switches the function of the Mute Control keys between muting and soloing (which is user selectable between exclusive or mix mode). SRND/ST basically switches between the selected surround format coming into the DS-M7.1 and stereo input from the dedicated CR stereo inputs on the rear panel. BUS/RTN switches monitoring between the bus inputs from the mixing console and the return inputs from the mixdown recorder. Down Mix/Mono switches between the selected surround format and the currently selected downmix mode (the downmix mode is selected using the System function key). When pressed together with the Shift key, this key combination downmixes directly to mono from any surround format.

A number of other controls are simply In/Out controls. Test is used during set up to turn the internal pink noise generator on and off. BASS MGT turns the bass management function on and off. Mute All cuts all the monitor signals simultaneously. Finally, Dim reduces the monitor output by a software selectable amount.

The rear panel of the DS-M7.1 is fitted with mostly DB25 connectors for analog and digital I/O. First there are two TDIF connectors for console and recorder I/O and a third 25-pin D-sub connector that sends and receives eight channels of AES/EBU that can be used for inserting a surround encoder/decoder into the monitoring path. There are also three expansion slots available for different types of I/O cards that can be used as an alternative to one of the three built-in I/O formats.

There are two sets of 25-pin D-sub connector monitor outputs, analog and digital, which work in parallel and provide up to eight channels of surround monitor outputs apiece. The Analog connectors work as balanced +4 dBu outputs, while the AES/EBU connector provides digital audio in AES/EBU format.
There are three sets of I/O connectors for the master recorder: TDIF, two lightpipe connectors, and a 25-pin D-sub for AES/EBU. A BNC connector is available to receive an external word clock signal complete with a 75-ohm termination switch.

Finally, there are two 1/4-inch +4 dBu inputs that allow the stereo CR outputs from a mixing console to be fed into the DS-M7.1 so that the same amplifier/speaker monitoring system can be used for surround and stereo monitoring, without repatching.

In Use
The DSM is one of the few units that has exactly the right feature set, with nothing meaningful left out or meaningless left in. Operationally it�s easy to use in that you can get around on it fairly well without a manual � providing that you�re already familiar with the basic concepts of a surround controller to begin with. While the D/A converters may not be what you�d call �top of the line,� they do sound really good considering the price of the unit.

TASCAM has done their homework well and included a lot of great features that are useful on a daily basis, but generally overlooked by the competition. Things like the built-in pink noise for calibration (complete with a band limited option), built-in bass management, and the ability to switch between the bus outputs of a console for surround and the stereo outputs are great.

About the only thing that I could even niggle a little about is the fact that, when you downmix to mono, the mix goes to Left and Right rather than to only the Center channel, but this is a small issue that can easily be addressed in a firmware update down the line.

Yet another thing to note is that the DS-M7.1 does not have its own internal clock, and therefore must be driven from an external source. If you don�t have a master word clock, you have to set it to derive clock from any of the source inputs. Failure to do this will result in the display blinking and the output being muted.

Price and Contact
The TASCAM DS-M7.1 is a certainly a well thought out and useful unit. Given the fact that so much studio work has shifted into the workstation from traditional analog consoles, the unit should easily find its niche anywhere that requires a mostly digital signal path. At a MSRP of $1899, you get not only a big bang for the buck in terms of feature set and capabilities, but one that sounds good and is easy to use as well.

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