Gotta Keep ‘Em Separated
The current Audio ER Class is being taught over in the “new” Studio C at Voicetrax SF. (For those of you who might not know the full history, it recently received a facelift, removing a wall between the engineering station and the main classroom.) This is the first time I’d taught there since the renovation. Luckily, I had engineered a different class in there and more importantly, had a private coaching session in that space a week or so before my class started.
One of the things which I noticed (particularly in the private, as we were listening back over the main monitors) is how much more resonance that room has now. The engineering space is pretty boxy, and this expanded area has plenty of uncovered, hard surfaces.
However, one other thing going on (cue “Teachable Moment” music…) is that Voicetrax dispensed with the separate speaker stands (for those who may not have spent a serious number of hours in the earlier space, the main classroom monitors stood on the west wall, but each one had a speaker stand which put them about 3-4′ high). Now, those monitors are sitting directly on the hard surface of the desk. In other words, they are in physical contact with a solid surface, and that solid surface is coupled with the wooden face of the desk, creating a resonant chamber. It’s kind of a quickie subwoofer.
Luckily, in my pile-o-parts, I own a set of monitor isolation pads, which I brought to the first class last week. Then I made them listen to the same audio with and without the pads. Everyone could agree they made a significant difference. The speakers no longer made the desk into a subwoofer.
This is one of those instances where if you made EQ changes on your audio based on how things sounded without the isolation pads, it would probably sound “thin” in a better tuned room. I’ve made it a practice of using the pads for playback (you sit the speakers on what are essentially big blocks of dense acoustic foam) which negates a lot of the enhanced boominess when the monitors were on the desk.
Isolating the monitors from any kind of surface is a good practice. Another reminder of how much the room can impact the qualities of playback. It is always active upon the sound.
What I brought in were these:
(they came in a combo box of assorted pieces for some deal a number of years ago – just never ended up using them) and you can generally find decent quality foam risers or other devices to acoustically isolate your speakers.