SSL Big Six soundcard calibration: level problems

[rklem]

Hi forum,

I'm taking my first steps with REW to measure my room – and therefore I'm trying to calibrate my soundcard: SSL Big Six.

I connected Big Six Main monitor out to Mic input 1 and selected those USB busses in REW. I set output and Mic 1 input level to max in the Big Six.
But still I only get -12 dbFs output level and -32 dbFs input level in REW when trying to calibrate the soundcard.

REW's "Control input volume" option is grayed out and can't be activated. I checked Big Six' in/out level settings in the MacOS audio settings, but there at max. already.

Any suggestions on how I can achieve proper levels for the soundcard calibration?

 

[John Mulcahy]

The inputs may have a larger full scale input voltage than the outputs. You can just go ahead with the levels as they are.

 

[rklem]

Thanks for your quick reply – but that doesn't work. It looks like I'm doing something fundamentally wrong here...

I tried before with another interface (Apogee Duet 2) and it worked, so I think I understood the process. There's just something about the Big Six that doesn't work (or that I'm doing wrong).

 

[rklem]

I assume calibrating the interface is neglectable when measuring a room, so could I just skip this?

 

[John Mulcahy]

You could skip it, sure, the main purpose is to make sure there's no monitoring feeding the input back to the output. That result looks like an unconnected input, though, so either the patch cable isn't in the right place or the output from REW isn't getting to the selected output channel.

 

[rklem]

Thanks, you were right. The REW output wasn't routed properly. For anyone facing the same problem, here's what I did now:

• REW Output: Big Six (USB Port 15): EXT IN 2 L
• REW Input: Mic Input 1 (USB Port 1)
• Big Six: Switch „EXT IN 2 FROM USB 15/16“ active, EXT 2 In Level: 0 dB, Master Fader: 0 dB
• Big Six: Gain +3 dB, Channel 1 Fader, „USB OUT POST FADER“ active, Ch 1 Fader: -5 dB
• Big Six: MUTE all Input Channels
• Cable Connection: Main Monitor Out L -> Ch1 XLR In

I think this is looking good now?

 

[John Mulcahy]

Yes, perfect.