[stevehobart]

I have just connected a new Denon 2900 DVD to my NAD T752 (via optical digital sound and component video). The front and centre speakers are driven through a NAD 906 bridged multi-channel power amp using the T752 pre-outs, the sub is connected using the T752 sub pre-out and the surrounds are driven through the T752. My speaker set up is: B&W 603 S3 fronts, B&W LCR600 S3 centre, Advent Legacy surrounds and an M&K V75 sub. All speakers are set to Large on the T752. (Also have a Strong SD digital TV box going to the T752 using component via Scart and Hantrex RGB to Component Box and then to a WideScreen LG 76 cm TV)


The video side of things is good - great picture quality.


There are, however, some funnies with the sound side of things from the Denon 2900.


1. DVD DD 5.1 is fine – all speakers driven including the sub

2. DVD DTS 5.1 does not drive the sub

3. CD – input to the T752 is shown as stereo but does not drive the sub – but when playing CDs on my Yamaha CDC565 CD player, with an analogue link to the T752, the sub is driven.


2. & 3. can only be rectified if all speakers are set to small on the T752.


I can’t understand why the T752 cuts out the sub with CD input from the Denon 2900 but does not with CD input from the Yamaha .


It also does not seem right that DVD DTS does not automatically pick up the sub with all speakers set to large on the T752 – it did with my previous “el cheapo†AWA DVD player.


Can anyone help ????? (Kris Deering ???????)

 

[stevehobart]

Come on you lot - surely someone has a Denon 2900 hooked upt to a NAD T752.


Is Denon Geoff still around ??????


Steve B.

 

[mdubrow]

Not sure if you tried this already, but there is a setting in the Audio Setup menu of the Denon DVD-2900 called "Bass Enhancer (2 Channel)". According to the manual, this setting should send bass sounds through the subwoofer if one is present. The default setting is OFF; you might try turning it ON and seeing if that cures what ails you.


If not, well, I'm fresh out of ideas.

Mike

 

[stevehobart]

Thanks Mike - I've got it set to ON and it makes no difference - and on my reading of the 2900 manual this setting only applies to SACD and DVD A.


I currenltly have speakers set to SMALL on the NAD T752 with the SUB x-over set to 120 and things are not too bad - but I still can't understand why analogue input from a Yamaha CD player will bring in the SUB with all speakers set to LARGE but the DENON 2900 will not do this using the OPTICAL DIG input.


Hopefully someone out there has an idea to overcome this.


Steve B.

 

[ehlarson]

The decoding is being handled by the NAD if you are using optical. This model has a lot of known bugs including problems with subwoofer output.

http://www.reviewcentre.com/review37419.html


THere have been firmware updates for it. Maybe that would help.

 

[Dean_Mc]

The Denon will output CD to the sub with the bass enhancer on but you have to use the analog connections not the digital. That takes all of the thinking away from the NAD. I think the setting on the NAD is EXT 7.1 (?) I suspect if you hooked your Yamaha up digitally it would act the same way - which is correct.


DTS doesn't actually have a .1 track so the NAD is acting correctly there if all of your speakers are set to large.


In most subwoofer-equipped systems, setting front speakers to "Small" is usually the better option. Try 80 hz for x-over.

 

[blgentry]

Quote:

DTS doesn't actually have a .1 track so the NAD is acting correctly there if all of your speakers are set to large.

I think you've made a mistake here. DTS is inherently a 5.1 channel format. My DTS DVDs absolutely provide an LFE (.1) output. Here's a quick overview of their formats from DTS themselves:

http://www.dtsonline.com/technology/at-a-glance.php


I wish I could be more help with the original poster's problem. The fact that you don't get the subwoofer output, via a digital connection, when using DTS, sounds like a receiver configuration issue, or reciever bug to me. Have you tried using the 5.1 channel *analog* outputs (6 RCA cables) from the 2900 to the NAD? That should remove all doubt as to where the problem lies. If you do this, make sure to configure and calibrate the multi channel sound settings in the 2900, as the 2900 itself will do all of the bass management and level setting when using the analog 5.1 outputs.


I'd go through the bass management setup section in the NAD manual and make sure you have everything set up to match the speakers you have. I.E., make sure subwoofer is set to "on" in the right place or places, etc.


Good luck,


Brian.

 

[Dean_Mc]

That's a very nice chart but the .1 in DTS is manufactured by the decoder - it isn't on the disc as a separate track. If all of the speakers are set to large it wont put anything out to the sub.


I have a Linn Unidisk SC that acts as a player and a processor and it behaves the same way as the NAD with DTS and speakers set to large. I can 'choose' to route material below 80 hz to the sub but the processor does it not the disc.


Here's a quote from the Secrets site


DTS's LFE channel is a little different._ In fact, in the cinema, DTS is actually 5.0 (as oppose to 5.1) in that there is no discrete LFE channel._ The LFE channel from the mixing sessions gets low-passed at 80 Hz and added to the surround channels._ In the theater, the surround channels are high-passed at 80 Hz with the reciprocal becoming the LFE channel._ The reasons for this multiplexing is one of space._ DTS's original encoder only handles full-bandwidth channels so a discrete LFE channel would require a full 20% more space on the medium (the disc) as if it were another full range channel.

http://www.hometheaterhifi.com/volum...pril-2000.html


Set your speakers to small - 80 hz x-over - use the analog outputs of the 2900 for music and you'll be set.

 

[blgentry]

Quote:

That's a very nice chart but the .1 in DTS is manufactured by the decoder - it isn't on the disc as a separate track. If all of the speakers are set to large it wont put anything out to the sub.

Quote:

DTS's LFE channel is a little different._ In fact, in the cinema, DTS is actually 5.0 (as oppose to 5.1) in that there is no discrete LFE channel._

Quote:

http://www.hometheaterhifi.com/volu...april-2000.html

I went and read parts of the above referenced post. The information you read applies only to the cinematic version of DTS, as it says in the quote above. If you read down further in the article, you'll find this quote:


"DTS's LFE channel in consumer applications, unlike its cinema counterpart, is discrete but still has a few 'special' considerations. In the early days of mixing 5.1 for DTS CDs, the studios were not being calibrated correctly, with the end result of the LFE channel being set too low."


"Discrete", as in a separate channel. DTS for home is a 5.1 channel format.


None of this will help the original poster, but I wanted to clarify the point.


Brian.

 

[Dean_Mc]

Thanks, I stand corrected - I wasn't aware of the difference between commercial and home applications. I had only skimmed the article to find a reference.


Noneheless, setting the speakers to small with an 80 hz x-over will more than likely solve the problem.

 

[stevehobart]

Thanks everyone for your input - setting speakers to small with a x-over of 80 does solve the problem and that's the way I'll go!


I've checked all the NAD iinputs and speaker settings and they are set correctly for sub W operations.


I have tried CD playback using the analogue links from the Denon 2900 but it is nowhere near as good as using the T752 for the processing - a bit veiled and dull in comparison.


I must point out that this is the only problem I have had with the T752 (which I have had for nearly two years now) except for its high operating temperature which is a bit better since I added a power amp for the front and centre speakers.


I'm also very happy with the Denon 2900 - great picture and sound - and also does a good job on CD, SA-CD and DVD- A - no problems with the unit at all so far.


Thanks again to all!


Steve B.