6-Channel vs. Digital for DTS

[paulsen]

<font color='#000000'>Both my DVD player (Yamaha C920) and my receiver (Yamaha RX-V530) have DTS decoders. I can play DTS DVDs using either decoder. When using the DVD's decoder the connection to the receiver is via 6-channel analog. When using the reveiver's decoder the conection is via the digital optical cable.

I have tried both methods and find that using the digital connection and the receiver's decoder is much better, but I don't understand why.

1. It shouldn't be a digital vs. analog issue since in both cases the signal is processed digitally then converted to analog just once -- it's only a matter of where this takes place.

2. Could it be that the DTS decoder in the receiver is better than the one in the DVD player? Would Yamaha really use an inferior decoder in this player? Both it and the receiver are new models in the same price range so I expect similar quality.

3. I don't expect any mis-match between these two components from the same manufacturer.

4. Could it be that the discrete connection (on either the DVD or receiver end) is somehow defective?

5. Since the most obvious difference is in the bass response is it valid and safe, for diagnostic purposes only, to connect the DVD player's discrete analog subwoofer output directly to the low-level input of my subwoofer?

Thanks for any advice! And thanks for the new FAQ in response to my previous question. A careful analysis of my system showed that all you said is true (esentially that DVD-Audio is &quot;out of the loop&quot; when it comes to base management and speaker delay configuration with my components).</font>

 

[Audioholics]

<table border="0" align="center" width="95%" cellpadding="0" cellspacing="0"><tr><td>

paulsen : <font color='#000000'>1. It shouldn't be a digital vs. analog issue since in both cases the signal is processed digitally then converted to analog just once -- it's only a matter of where this takes place.

2. Could it be that the DTS decoder in the receiver is better than the one in the DVD player? Would Yamaha really use an inferior decoder in this player? Both it and the receiver are new models in the same price range so I expect similar quality.

3. I don't expect any mis-match between these two components from the same manufacturer.

4. Could it be that the discrete connection (on either the DVD or receiver end) is somehow defective?

5. Since the most obvious difference is in the bass response is it valid and safe, for diagnostic purposes only, to connect the DVD player's discrete analog subwoofer output directly to the low-level input of my subwoofer?</font>

<font color='#000000'>1. There is more distance to travel when D/A conversion takes place on the DVD player. And your analogue audio cables are now carrying the analogue signal to the receiver.

2. The bass management that is going on is probably a lot better in the receiver than in the DVD player. Just run the numbers and see what each gear has to do for the price.

3. No, this shouldn't be an issue

4. No, probably not.

5. Not sure why you would want to do this as it would result in splitting your bass management into a voodoo-ish type of mixture between the DVD player and the receiver. Definitely not a scientifically fair testing procedure.

It is generally best to capitalize on the (usually) superior electronics of the receiver for decoding DTS signals.</font>

 

[paulsen]

<font color='#000000'><table border="0" align="center" width="95%" cellpadding="0" cellspacing="0"><tr><td>

hawke : 1. There is more distance to travel when D/A conversion takes place on the DVD player. And your analogue audio cables are now carrying the analogue signal to the receiver.

2. The bass management that is going on is probably a lot better in the receiver than in the DVD player. Just run the numbers and see what each gear has to do for the price.

3. No, this shouldn't be an issue

4. No, probably not.

5. Not sure why you would want to do this as it would result in splitting your bass management into a voodoo-ish type of mixture between the DVD player and the receiver. Definitely not a scientifically fair testing procedure.

It is generally best to capitalize on the (usually) superior electronics of the receiver for decoding DTS signals.

For experimentation, I am using &quot;The Lord of the Rings, Fellowship of the Rings&quot; prolog section to evaluate LFE response of DTS. LotR has *lots* of LFE. There is a huge difference in bass response between DVD decoder via 6-channel vs. Receiver decoder via optical connection.

In response to your responses...

1. I think a difference in cable length would have a much more subtle effect than what I hear. At first I wasn't sure there was even a signal coming from the the receiver's LFE output when using DVD decoder via 6-channel input. Once I confirmed that there was actually a signal it was so low I thought it just might be cross-channel leakage until I removed all but the LFE cable between the DVD and the receiver.

2. You are probably right about this. But, the DVD player actually has *more* configuration options than the receiver does (e.g. rear-channel delay), raising my expectations.

3. Agreed.

4. Still suspicious, and this is the reason for my number 5 ...

5. I want to try the direct hookup from DVD to subwoofer just to &nbsp;evaluate how good a signal is coming out of the DVD. If this gives me the full bass then I can blame the receiver's handling 6-channel input instead of anything in the DVD. Just a diagnostic tool, not intended to be my actual configuration.

So my remaining questions are: Is it safe to do this? Is the DVD analog output compatible with what the subwoofer expects as low-level input?</font>

 

[Audioholics]

<table border="0" align="center" width="95%" cellpadding="0" cellspacing="0"><tr><td>

paulsen : <font color='#000000'>5. I want to try the direct hookup from DVD to subwoofer just to  evaluate how good a signal is coming out of the DVD. If this gives me the full bass then I can blame the receiver's handling 6-channel input instead of anything in the DVD. Just a diagnostic tool, not intended to be my actual configuration.

So my remaining questions are: Is it safe to do this? Is the DVD analog output compatible with what the subwoofer expects as low-level input?</font>

<font color='#000000'>Regarding 5 in particular, there should be no problem with placing a line level signal (from the DVD player's LFE, or subwoofer output) into your sub directly.

But... Could the problem simply be a level difference of the LFE setting on the receiver? Setting the LFE has always ben the mystical setting that lots of people generally set by ear rather than with the SPL meter method. I often change my setting between movies and music... Just a thought.

As a troubleshooting step, what was the LFE setting on your receiver set to?</font>