JBL MSC1 Monitor Controller

The MSC1 is both a sophisticated room-correction tool and a robust controller for use with any two pairs of speakers and a subwoofer.
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The MSC1 is both a sophisticated room-correction tool and a robust controller for use with any two pairs of speakers and a subwoofer.

Working as a freelance recording engineer in Nashville often means that you find yourself in a different listening environment every few days. Small and mid-sized studios, much like home studios, don’t always offer the most accurate control room listening environment. In these conditions, an engineer often relies on his own monitors to provide perspective that allows for mixes that translate well to other playback systems. JBL’s MSC1 is a feature-filled monitor controller that also offers its RMC Room Mode Correction system, to provide more accurate monitoring in less than perfect environments. [RMC is included in JBL’s popular LSR6300 and LSR4300 Series monitors, too -- Ed.]

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The MSC1 ($375 list, $299 street) is housed in a sturdy desktop-ready chassis. All I/O is on the back of the unit, allowing for three separate stereo sources: two input pairs are available via balanced quarter-inch TRS and one set is via unbalanced RCA connectors. Outputs to two sets of monitors and one subwoofer are all provided via quarter-inch balanced TRS outputs. There is also a quarter-inch headphone jack, eighth-inch I/O jacks for the RMC mic, and a USB connection to utilize the RMC process with your host computer (more on RMC later).

A large volume knob in the center of the unit allows for volume control of the two sets of monitors (sets A and B), along with control over a subwoofer to work in conjunction with the “A” monitors. Along the top, you find headphone volume control, A and B Speaker select, a two-button matrix for selecting one of the three possible stereo inputs, and an input level trim. Underneath this trim are two LED indicators which indicate signal presence and clipping. Around the large volume knob are lighted on/off buttons for the sub, RMC, EQ, and mute.

The MSC1 also ships with a calibration mic, USB cable, and eighth-inch TRS cables.

More About RMC

JBL’s third-generation Room Mode Correction processing capability is what sets this monitor controller apart from a standard controller. The most common acoustic problem in control rooms, especially smaller ones, is the lack of proper bass handling. The RMC process allows you to compensate for this by accurately measuring your listening environment, then setting filters in the MSC1 to correct bass inaccuracies. If needed, it also allows you to use trim and delay to compensate for less than perfect speaker positioning, a two-band high and low shelving EQ, and adjustable crossover settings for the subwoofer. It should be noted that RMC is designed to work with any make or model of speaker.

The RMC features are accessed via your host computer, and settings are applied to the MSC1 via USB connection. Once calibration is complete, computer connection is no longer required. While conducting this review, RMC software was available for PC only, but JBL reports that the Mac version will be soon available.

In Use

For the past few years, my monitor of choice has been the JBL LSR6328P alongside using the venerable Yamaha NS-10 as my alternate set. The MSC1 fit in well with this setup, having my JBLs as the A speaker -- which has access to all the processing features -- and the NS-10s as the B set, which are not processed.

First off, the MSC1 powers up and down with all the outputs muted -- a nice feature not always found in other monitoring systems. The large lighted buttons for the RMC, Sub, EQ, and Mute buttons, along with the very large volume knob make it easy to use in most any dimly-lit studio. Speaker select and Input select buttons are unlit, but are still easy to distinguish. The Input Trim knob affects whatever source you have selected, so it acts as an overall level preset rather than a calibration tool for the individual inputs.

Aurally, the unit is transparent. Granted, you are listening through converters in order to use DSP for the MSC1’s processing abilities, but I did not find this to cause any difficulty in monitoring accurately.

Initially configuring the MSC1 takes a bit of time in order to specify and test your particular setup, as the software uses your computer’s soundcard or audio interface. Subsequent calibrations are a lot faster and easier. A number of the on-screen controls allow you to fine tune the performance of the MSC1 to your setup -- for example, you are able to adjust the A speaker level, adjust subwoofer level, polarity and crossover frequency. Using RMC in a shallow control room produced a very noticeable benefit in monitoring low frequencies and how those mixes translated.

On a personal note, I would like to save multiple RMC calibrations in order to have a saved calibration for each of the different studios where I work. Yet, I must note this positive attribute of the MSC1: the most recent RMC calibration is stored in the unit even when unplugged, so I don’t have to leave the PC connected to it post-calibration.


The MSC1 is a great product not only as a robust monitor controller, but it is a sophisticated tool for room correction. Its solid feel and the amount of available connectivity combined with its RMC abilities make it a very attractive choice to engineers on the go and/or those that frequent acoustically-troublesome listening environments.

John Saylor is a Nashville-based independent engineer. Find him at

Price: $375 list

Contact: JBL Professional | 818-894-8850 | jblpro.com