I have a NAD t-753 receiver and I've being using it's test tone to level match my 5.1 system. I use an SVS pci 20-39 sub. Today I set up using a digital video essentials DVD and it showed the bass volume to be 20dbs higher than what the other speakers were set at. If I use the DVE settings the sub is 20dbs too low according the the receivers test tones. The other 5 speaks are the same with either test tone. Does any one have an explanation for the different readings and which one is accurate?

I have a NAD t-753 receiver and I've being using it's test tone to level match my 5.1 system. I use an SVS pci 20-39 sub. Today I set up using a digital video essentials DVD and it showed the bass volume to be 20dbs higher than what the other speakers were set at. If I use the DVE settings the sub is 20dbs too low according the the receivers test tones. The other 5 speaks are the same with either test tone. Does any one have an explanation for the different readings and which one is accurate?

Search for "DVE low LFE" or words to that affect.

The .1 channel on DVE is not encoded correctly. There was a ton of discussion on that when DVE came out.

Joe Kane denies it, but some pretty thorough investigations were done by some of the users here, and the bottom line is the disc is wrong.

Brian

That is new information to me however it still seems odd for there to be such a wide margin of error. I just tried using other setup test tones including the Avia disc the thx test from the starwars III disc and the ultimate dvd surround sampler and 5.1 set-up disc from Chesky they all varied for 15-20db less than what the receivers test signal showed. I've concluded that the receivers sub test tone must be off but I can't accurately tell by how much.

I found this thread after a quick search, which does mention the issue.

http://www.avsforum.com/avs-vb/showthread.php?t=1085726&highlight=dve

But I did not turn up the original threads when DVE was released.

A user named EdwardJM (I think) who now works for SVS Subwoofers, did the most detailed evaluations. seems like it was high by about 8 to 10 dB, meaning if you used it, your sub would be LOW by that amount.

The thread linked here does say it has been fixed, but all I can say is "Not Mine". AVR tones are usually spot on for the main channels, but for me it has been hit and miss with the sub tones.

Good luck.

Brian

There is some discussion of it in the FAQs at the DVE site, too.

I think the issue has something to do with encoding subwoofer calibration tones specifically in the LFE channel. The AVIA calibration tones are not encoded in the LFE channel, but the main channels, and are meant to be bass managed. The tone actually warbles and moves back and forth between the speaker and the sub as it changes pitch. The goal is to make certain that the SPL remains the same as it moves back and forth between the speaker and sub. Works quite well.

Thanks for the help. I think I understand some of what is going on. I''ll try the Avia tests and hear how that works. For now though I've made a compromise, I turned down the sub from where it was and It sounds more realistic.

Thanks for the help. I think I understand some of what is going on. I''ll try the Avia tests and hear how that works. For now though I've made a compromise, I turned down the sub from where it was and It sounds more realistic.

Bingo.

No matter what the tones or the meter says, your ears are really the final test, right? If after calibration, you think the sound is too bassy or too lean, a few clicks on the sub level will usually do the trick.

Here is a link to some set-up tips for using Avia:

http://www.keohi.com/keohihdtv/experttips/guykuo/avia/avia_a2z.html

The sub stuff is way down towards the bottom.

Brian