Chained Sub Pre-outs...what's the truth?

[Tomorrow]

I guess this subwoofer section is as good a place as any to post this possibly dumb question. (You'd think I'd been on here long enough to have picked up this information. ) It has plagued me since I acquired my first Panasonic DVD player and continues with my new BD-55. There are a couple of threads running concurrently that expose others' ignorance of the issues involved, as well. So I guess misunderstanding of the technology is rife. The problem is usually expressed as "I just hooked up my shiny new Blu-ray player, I want to use the analog 5.1 or 7.1 setup, but am getting no bass to my sub. Is my player defective?" Well, we know that sub signals are there but are reduced significantly compared to a duplicated digital connection. We also know that there are work-arounds that easily solve the problem.

BUT....will one of you good technically non-challenged people please answer the following question: Is there a reduction in pre-amped signal strength when the sub pre-out from a multichannel analog source is connected through a receiver (or pre/pro) to a subwoofer? For example....a BD-55-->RX-V2500-->VTF3

Inadequate DVDP bass management features issues aside, is there a diminishing of the electrical signal? Is it a lack of signal strength that causes this perceived problem? I'd just go measure it but I don't have the equipment.

TIA

 

[Tomorrow]

Okay...this is either a really stupid question no one wants to embarrass themselves or me by answering...or nobody knows the answer.

C'mon boys...the truth is out there.....I can take the humbling....

 

[mike c]

i doubt there's much loss ... if there is, the receiver can always bump up the subwoofer channel a few db's.

other than that, i honestly don't understand what's going on HDMI!

 

[croseiv]

So, with my S550 I did have an issue with lower bass output running the multichannel outs as compared to optical with my other DVD player. However, this was overcome decreasing the output of my mains center, surrounds, boosting the gain on my subs a bit and recalibrating. I now have to adjust my volume up about 3 dB more than before, but I garantee I couldn't tell the difference now compared to how it was set before (blu-ray bass management vs recevier's bass management even with the uncertainly of the cross-over). I have been very impressed with the SQ of the Sony.

 

[Tomorrow]

So, with my S550 I did have an issue with lower bass output running the multichannel outs as compared to optical with my other DVD player. However, this was overcome decreasing the output of my mains center, surrounds, boosting the gain on my subs a bit and recalibrating. I now have to adjust my volume up about 3 dB more than before, but I garantee I couldn't tell the difference now compared to how it was set before (blu-ray bass management vs recevier's bass management even with the uncertainly of the cross-over). I have been very impressed with the SQ of the Sony.

Thanks for the input, croseiv. Yes, this is one of the work-arounds.

But I still wonder....WHY does it present decreased output?

 

[Tomorrow]

i doubt there's much loss ... if there is, the receiver can always bump up the subwoofer channel a few db's.

other than that, i honestly don't understand what's going on HDMI!

Mike, you're so funny. Oh, and would you mind loaning me a couple of bills (large). A Z7 loaded with HDMI is prezactly what I'd like/need.

 

[croseiv]

Part of the problem, at least with the Sony's bass management is that you can only decrease the levels. This is something that can be fixed with a firmware update, but one can work around it as I have, as such though, one can't boost the sub's level out of the box.

 

[Tomorrow]

Part of the problem, at least with the Sony's bass management is that you can only decrease the levels. This is something that can be fixed with a firmware update, but one can work around it as I have, as such though, one can't boost the sub's level out of the box.

'Tis the same with the BD-55.

 

[croseiv]

'Tis the same with the BD-55.

Now that's interesting. I wonder why they configured it that way? I don't really see it as an issue though as I have gotten around it with great results. I have been very impressed with the Sony's SQ (and PQ). I have found that there seems to be a pretty big (better) difference with the HD tracks.

 

[Tomorrow]

BUMPITY....still looking for wisdom here. Where are the tech guys with the a/v workbenches and electrical testing equipment? Gene...where are you? (He must be busy in the Garbage Collector Tipping thread. )

What's the answer to the double pre-out question?

 

[Tomorrow]

BUMP AGAIN.

I can't believe that with the collective techical wisdom of this forum, nobody knows why M/C DVD subwoofer output is diminished when passed through a receiver.

 

[mike c]

BUMP AGAIN.

I can't believe that with the collective techical wisdom of this forum, nobody knows why M/C DVD subwoofer output is diminished when passed through a receiver.

i think this i know (ok, im guessing) ... it is not diminished BECAUSE it was passed through the receiver. i believe the multichannel outs of these players have by default a specific -10db thingy on the LFE channel i think

 

[croseiv]

i think this i know (ok, im guessing) ... it is not diminished BECAUSE it was passed through the receiver. i believe the multichannel outs of these players have by default a specific -10db thingy on the LFE channel i think

Yeah, now that you mention it, I seem to recall this as well.

 

[Tomorrow]

i think this i know (ok, im guessing) ... it is not diminished BECAUSE it was passed through the receiver. i believe the multichannel outs of these players have by default a specific -10db thingy on the LFE channel i think

Thanks, Mike. I've heard this before. Of course the question then morphs into "why do they do that?"

But I'm still curious if the pre-outed dvd signal is unchanged as it gets pre-outed by the receiver. Damnit, inquiring minds want to know.