John Sayers' Recording Studio Design Forum Archive

I tried eliminating the Central Station from the chain but this didn't do anything. I also tried different cables between the central station and the subwoofer. No changes.

I next switched interfaces--here's results with mic-->Topaz mixer-UAD Apollo16-->central station-->subwoofer->Mackies. As you can see, it doesn't seem to have changed much of anything). For the heck of it, I also ran sweeps with a SM57 and an AT large-diaphragm condenser. (These aren't calibrated to actual SPL levels, but you can see the low-end response doesn't change.)

So...weirdly flat in an area that we'd expect problems in an empty room, and nothing to speak of below 35hz. Weird! But, it appears to be accurate. Listening to some test tones and sweeps at the listening position it appears to be true to what I hear with my ears. So... where do we go from here?

My efforts to figure out if anything could be altering the measured room response are still coming up short. Would it be helpful to see how things change when I add some simple treatments at the first reflection points?

My efforts to figure out if anything could be altering the measured room response are still coming up short.

I would keep trying at that, until you figure it our: something is inserting a fairly steep filter in your signal path. Try it with a totally different laptop computer, install nothing else except REW, and go direct form the headphone out to the speakers, using the built-in mic on the computer as the measurement mic. The frequency response will be badly off, yes, but at least we'll see if there's a difference. Also try with different speakers (borrow some!).

Would it be helpful to see how things change when I add some simple treatments at the first reflection points?

You can if you want, but I would start with the back wall first. And I'd REALLY go searching for that EQ problem first.


- Stuart -