When calibrating level/EQ of sub with REW - 2 channel mode or PLII/x ?

[Buckster]

just wondered why I get a difference in gain of about 5dB of the sub using REW in

2 channel mode (inc sub)

vs

PLIIx (where sub seems when running REW to be about -5 to -6dB too low ..)

or is it just with the extra channels playing it "mucks up" the calibration

thanks very much, Buckster

[brucek]

just wondered why

Because REW is always to be used in stereo mode. No soundfields allowed because they work on phase and REW is a mono signal........

If you want to test all your speakers you can simply connect each one to a left or right mains position.

brucek

[Buckster]

brucek - spot on - makes sense and thanks for the answer to a noddy question

one other quick one while I'm on it - I'm using the digital output (skipping the soundcard calibration part) - with the assumption that in a decent av amp (I have a Pioneer 59TXi) - that the digital signal/converted signal should be as good as perfectly flat ?

cheers, Buckster

[brucek]

one other quick one while I'm on it - I'm using the digital output (skipping the soundcard calibration part) - with the assumption that in a decent av amp (I have a Pioneer 59TXi) - that the digital signal/converted signal should be as good as perfectly flat ?

Well, the digital output is flat, but the line-in for the mic to REW will not be flat and so you can't use the digital output.

You need to do a soundcard calibration that compensates for the line-in and line-out of the soundcard.

brucek

[sendtobrit]

brucek wrote:

Because REW is always to be used in stereo mode. No soundfields allowed because they work on phase and REW is a mono signal........

If you want to test all your speakers you can simply connect each one to a left or right mains position.

brucek

Question: Am I only measuring the R main with the sub? Or, do I use a Y-cable and send the mono signal to both L & R mains to test them with the sub together?

Also, if I use the Y-cable and put the AVR in PLIIx I can isolate the Center if I unhook the speaker connections to the R & L mains, right?

[brucek]

Or, do I use a Y-cable and send the mono signal to both L & R mains to test them with the sub together?

Sometimes it's good to do both the mains separately with the sub, and then also play them together with the sub. This gives a reveal of whether any peaks or dips are caused by one speaker or the other or both together.

if I use the Y-cable and put the AVR in PLIIx I can isolate the Center if I unhook the speaker connections to the R & L mains, right?

Nope, you must use stereo at all times when you use REW. No soundfields allowed. If you want the center, plug that speaker cable into the right or left main output temporarily.

brucek

[sendtobrit]

Sweet--that's very helpful BruceK.

Much appreciated...