Hope it’s the right area to ask for help

I am in need of advice. I'm ready to calibrate my system with an SPL meter, but I do have a question. I have a NAD T744 receiver running my L&R surround. I also have a NAD 916 six channel amp bridged to three channels to run my L, C, R fronts. I’m trying to use my digital SPL meter from radio shack. I want to know how loud I should set my receiver to start my calibration. The receiver has a volume from -74 to +18. I have the NAD 916 amp INPUT LEVEL at thirty percent in bridged mode.

Set it to 0.

Thanks!

May not be quite that easy.... You need to try the receiver to see what it does during calibration.

Some units disable the master/main volume control during calibration. If yours does this then it generally means the calibration is referenced to the 0dB volume setting.

In that case, you would need to adjust your amp gain controls so when the individual channel trim is at the midpoint (0dB), the SPL is close to 75dB. Then, you'd do a fine tuning with the individual channel trim, as required, to dial right in on 75dB.

If the main/master volume is adjustable during calibration, then I think you'd want to check what volume setting produces 75dB on the surrounds when the trims are at 0dB. Then, use that volume setting and backtrack to the mains and center to set the amp gains to bring those to 75dB with the trim levels at 0dB.

The risk with actually setting the main/master volume to 0dB if the receiver isn't designed that way, is that you may not be able to get 75dB calibration level...may be too loud and not enough adjustment on the channel trims to bring it down. Besides, I usually like to try to keep the channel trims near 0dB if possible, not one extreme or the other.

FWIW, the NAD manual doesn't seem to say anything about the master/main volume setting during calibration. I could assume this means it internally defaults to the 0dB point, but that might not be correct.


Clear as mud?

Got it!

if u haven't done it yet, just put some plugs in your ear. want to save your hearing :) it can get quite loud with the test tones. :eek:

I have WALL-E on Blu-ray it has a sound noise test. Can I use that to calibrat or use the NAD receiver

I have WALL-E on Blu-ray it has a sound noise test. Can I use that to calibrat or use the NAD receiver

I use the test tones in my processor for calibration, FWIW.

thanks for the help. It made a big difference and yeah it was load

I have WALL-E on Blu-ray it has a sound noise test. Can I use that to calibrat or use the NAD receiverPink noise (reference) should be more effective than simple (tone) sine wave..your SPL meter will behave much better with PN. With a tone the meter will interact way more with the ambient conditions i.e. dramatic peaks and nulls will cause significantly different readings as the SPL meter perspective is varied.