NAD T751 Issue

[oakleaf]

There is no sub out going through the digital audio inputs. Mains, center and surrounds work fine. Unit is set to "Small" on these with "On" for sub. Using Avia's HT set up DVD, low bass comes through all speakers except no output through sub. Interestingly sub works great when EXT 5.1 is selected. Any one have experience with this? Thanks!

[oakleaf]

Any one can jump in!

Further analysis uncovered the following:
(1) "Test" mode on T751 does not send an audio signal to sub, even though it displays subs. Test sends 3 sec audio signal to LF > RF > C > RS > LS > Sub, sending an audio signal to all but sub so you can set balance. You can still set balance to sub here but its a guess.
(2) "Ext 5.1" works (meaning analog audio out from DVD player), so sub, amp, connections are correct.
(3) I used the Avia HT setup DVD to set sub level. No output signal to sub at all.
(4) Played the "Lift-off" Chapter 13 from "Apollo 13" last night. The sub worked with this DVD with the Dolby Digital digital audio out from DVD player!
(5) No signal to sub from the STB Dolby Digital digital out to T751.

So the plot thickens. Why did the sub work for "Apollo 13" but not the "Avia" DVD or through the STB digital out?

[Briz vegas]

I am not clear on your settings and what is "STB" ???

Audio can go the the receiver via digital (optical or coaxial) or analogue - are you saying you are using one of the digital inputs (ie digital to analogue conversion in the NAD)

Audio out is via the pre-outs (including the .1 sub signal) or via speaker connections (for your 5 surround channels)- is this how you have it set up - ie sub via the pre-out sub connection?

Are you saying that when the NAD does the digital to analogue conversion it does not send the low frequency effects audio signal to the sub? i assume that you have also turned up the sub volume setting and there is still no test tone?

[oakleaf]

Briz,

I am not clear on your settings and what is "STB" ???

"STB" is the Samsung Set Top Box ATSC tuner. It has a digital audio output.

Audio can go the the receiver via digital (optical or coaxial) or analogue - are you saying you are using one of the digital inputs (ie digital to analogue conversion in the NAD)

Yes, the digital outputs from the STB and DVD universal player go into the NAD T751 Video1 and Video3 digital audio inputs, respectively.

Audio out is via the pre-outs (including the .1 sub signal) or via speaker connections (for your 5 surround channels)- is this how you have it set up - ie sub via the pre-out sub connection?

Correct, the Subwoofer pre-out goes to the subwoofer amp.

Are you saying that when the NAD does the digital to analogue conversion it does not send the low frequency effects audio signal to the sub?

That is correct.

i assume that you have also turned up the sub volume setting and there is still no test tone?

That is also correct.