MC3™ Development

The Radial MC3 was developed to address several 'not so obvious' problems that are common in today's recording studio. Radial president Peter Janis explains: "I was in England, trying to do in-store demos with our Primacoustic Recoil Stabilizers. The easiest way to do this is to set the playback system to mono and then pan between one loudspeaker that is on a Recoil while the other is on a piece of foam or countertop. But when we asked the shop techs to do this, we quickly found out that summing mono on many of today's digital workstations is not that easy. It appears that you often have to digitally mix the left and right to mono which can take time and effort. Considering how important this is for checking AM radio compatibility, I was immediately intrigued. This got me thinking. How could we easily sum the output of a stereo system to mono? And as usual, one thing led to the next and the idea for the MC3 was hatched.

"Then, while in Beirut I was treated to a visit to one of the top producer-engineer's private studio. While there, we listened to a production he was working on for National Geographic while switching between three different sets of monitors. It was interesting to see how the engineer built up the mix from his Yamaha NS10s, then how he compared it to the sound when playing the tracks back over his Tascams and then to his Dynaudio speakers. He then added the sub to hear how things were all working. He said it took him a while to get it all to work, but his cocoon had become a comfortable creative space for making music. As I watched this master at work, it became clear to me that he was constantly changing the master level control to hear how the mix worked at lower and higher levels."

Setting the boundaries
If you were to design the perfect small room monitor switcher what would it be? We quickly came to the conclusion that we did not want to compete with some of the high-end switchers that already were available. Instead, we decided to focus on building an affordable switcher that would address some of the key problems that we discovered during our market research. The basic design would be a compact monitor switcher that would enable the user to switch between two sets of monitors, be able to add a sub and then be able to mute the system when auditioning through headphones.

Passive switching for 'straight wire' performance
The problem with active switchers is that they introduce an electronic circuit in between the output of the recorder and the playback monitors. This can introduce coloration and distortion. We chose to make the Radial MC3 completely passive. In other words, the only thing in between the output of the recorder and your monitors are resistive components in the form of potentiometers that let you attenuate the signal.

To ensure a smooth transition from zero to ten, a custom made stereo potentiometer with matched resistive taper was employed with less than 0.5dB deviation at any one point. This single control would enable the user to adjust all levels at the same time for easier manipulation. To help retain accurate mix levels during interruptions, we added an adjustable dim control. This enables you to hit a switch to lower the level without touching the main control knob.

Controlling the monitors
As the target audience would be the project studio, we figured that two sets of monitors would be sufficient. Two front panel switches would enable the user to select which one to use. We decided that individual 'trim controls' on each output would be cool as it would enable the user to set the levels without having to reach back in behind the loudspeaker to make adjustments. In other words, you could sit in the mix position and set the levels more efficiently.

This would of course be equipped with a mono-sum switch to check for AM radio compatibility and phase checking microphones. It is surprising how often a stereo signal can accidentally by reversed. By hitting the mono sum switch, you can quickly test. If the signal seems distant, you may well be out of phase!

Getting down to the bass
We then decided to add a switch to allow a sub-woofer to be added or turned off as needed. This of course necessitated summing the left and right signals to mono. This is done actively so that it will not affect the signals going to the monitors. This output, although designated for a sub, is actually a full range mono output. The sub will be equipped with a low pass filter to set the cut-off frequency. A separate level control on the MC3 is used to fine tune the output so that you can adjust levels from the listening position.

Mixing to headphones
With more and more folks downloading files to their iPods, checking your mix with headphones is a must. Following the lead set during the Workhorse development, we chose to outfit the MC3 with two headphone outputs. This lets the engineer share the mix with the producer as they listen together. We then added a stereo 3.5mm (1/8") TRS output for ear buds... because you will want to also check this format to ensure your final mix appeals to the broadest audience.

Finally, we chose to use the ¼" TRS extra jack on the rear as a stereo auxiliary output that is fed from the active headphone buss. This way, you could, for instance, feed another studio headphone system, remote monitors or even a stereo recorder using the aux output. This runs parallel to the headphones and conveniently uses the headphone volume control to set the output level.

The MC3 was shown for the first time at the 2011 AES Show in New York and it immediately drew the attention of top engineers, producers and magazines - winning a coveted Best Of Show from Music Player magazine.