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Old 16th April 2009, 12:57 AM   #981
gedlee is offline gedlee  United States
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Yes, that works too. But being active makes for a headache (power supplies, grounding, etc.). I like passive whenever possible because of less potential for problems.

You could use Y-RCA's if you used padding resistors. Since the DCX has so much gain, this might work fine.
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Old 16th April 2009, 01:03 AM   #982
gedlee is offline gedlee  United States
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Quote:
Originally posted by markus76


Which box are you talking about? The BassQ? Didn't you read the manual?

"Although the
system has been designed to work
with the rest of the Performance Series
system, including AV1 and AVA7,
the unit can be used in almost any
system and can improve the in-room
response of almost any installation."

"There are two subwoofer inputs.
If using an AV1 processor or other
processor that has a single subwoofer
or LFE output
, connect the subwoofer
output to the Left input and set the input
mode to Mono on the front panel of the
JBL BassQ unit. [...] If you are using
a preamp/processor such as the AV2,
or an AVR that has stereo subwoofer
outputs
, connect the left and right
inputs and set the mode to Stereo on
the front panel of the JBL BassQ unit."



But you still don't have the LFE in the speakers.



What more proof do you need than real world data I posted??

Markus

Markus

Your data didn't prove a thing. Only that there was LF output in the center channel NOT that it was any different than what was in the left and right.

And when you set the AVR to "NO Sub" then the LFE is sent to the mains and hence gets to the DCX.

The JBL box REQUIRES the same signals as the DCX period.
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Old 16th April 2009, 01:06 AM   #983
pjpoes is offline pjpoes  United States
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Quote:
Originally posted by amiklos



I have a hard time believing that there is much unique LF content sent to those surround channels, at least not enough to justify the complexity of the system being suggested (yes I saw Markus's data). While in theory there may be something that gets missed, what is the practical impact in the course of 99% of listening? Studios aren't really expecting the average consumer to have 5hz-20khz reproduction on each channel are they?

Even if you did want to combine all the LF info from all the channels, what prevents you from using a mixer to sum sets of channels ahead of the DCX rather than needing several DCX units? The goal is still to send the same LF info to all subs (with requisite processing in place), correct?
Your right, I had misunderstood what was originally being suggested. I thought something else was being suggested, but this all makes sense.
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Old 16th April 2009, 01:08 AM   #984
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Quote:
Originally posted by amiklos
I have a hard time believing that there is much unique LF content sent to those surround channels, at least not enough to justify the complexity of the system being suggested (yes I saw Markus's data).
So what you're basically saying is "Yes I saw the proof but I'm ignoring it and state the opposite". Admittedly one DVD is not representative but I'll definitely check more DVDs in the future. And there will be a lot of thanks to Netflix.

Best, Markus
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Old 16th April 2009, 01:12 AM   #985
pjpoes is offline pjpoes  United States
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Click the image to open in full size.

This is an example of a simple unbalanced to balanced circuit. If you look at the first opamp, you can add the L, C, and R inputs to tag two by having each one have it's own 33k padding resistor. Then all would be combined with no cross talk issues. While it's not necessary, and if you had to buy it, I wouldn't recomend it, you can make it with 3 single opamps (or two duals), and have the benefit of a little lower noise and no cross talk issues.

I've not used this DCX device, but I did use the older DEQ eq unit, and I had so many problems with it. The huge amounts of gain as well as the passive unbalanced to balanced and back again caused a lot of hiss. I think using this mentioned device would fix that maybe, but I would need to pick up a DCX and try it.
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Old 16th April 2009, 01:15 AM   #986
amiklos is offline amiklos  United States
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Quote:
Originally posted by markus76


So what you're basically saying is "Yes I saw the proof but I'm ignoring it and state the opposite". Admittedly one DVD is not representative but I'll definitely check more DVDs in the future. And there will be a lot of thanks to Netflix.

Best, Markus
I'm saying, "I saw Markus show that there was LF content". You didn't show unique content, and I made a point of noting that in the comment you quoted.

Your tone has become quite combative lately. I'm unclear as to the cause.
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Old 16th April 2009, 01:28 AM   #987
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Quote:
Originally posted by gedlee
Your data didn't prove a thing. Only that there was LF output in the center channel NOT that it was any different than what was in the left and right.
Are you sure about that? A few posts ago you were sure that there is no low frequency content in the center channel at all. I feel better by looking at facts and real world data instead of adopting a belief.
Even if the low frequency content in each channel is the same, you might end up with the bass level being to low because you ignore the signal from C, LS, RS, LB, RB.

Quote:
Originally posted by gedlee
And when you set the AVR to "NO Sub" then the LFE is sent to the mains and hence gets to the DCX.
That's correct. But what if the audio engineer decides to mix some low frequency content only to L and R? 3 to 5 of your sources will drop out of your low frequency array.

Quote:
Originally posted by gedlee
The JBL box REQUIRES the same signals as the DCX period.
As I said before I don't know what the BassQ does so I don't know what signal is best. I don't want to promote that box in any way. But the manual is pretty clear that you simply need the sub out which is available from every AVR.

Best, Markus
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Old 16th April 2009, 01:40 AM   #988
pjpoes is offline pjpoes  United States
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Quote:
Originally posted by markus76

As I said before I don't know what the BassQ does so I don't know what signal is best. I don't want to promote that box in any way. But the manual is pretty clear that you simply need the sub out which is available from every AVR.

Best, Markus

Isn't that because it's a different approach which promotes high passing all speakers and not using them as additional LF sources.

I do think there is a problem with highpassing. In my opinion, based on my understanding of LF small room acoustics, you really want to deal with the LF problem at the transition point. That means either removing the mains from the LF equation completely or replicating the LF content across all the LF sources, including the mains. Highpassing the mains doesn't do the same thing as replicating the LF content across all LF sources unless it's high enough in frequency.
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Old 16th April 2009, 02:07 AM   #989
gedlee is offline gedlee  United States
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Quote:
Originally posted by markus76
A few posts ago you were sure that there is no low frequency content in the center channel at all.

Best, Markus

I never said that, you are completely misunderstanding the issues and your attitude has turned me off, so I am done.
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Old 16th April 2009, 08:12 PM   #990
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Quote:
Originally posted by pjpoes
Highpassing the mains doesn't do the same thing as replicating the LF content across all LF sources unless it's high enough in frequency.
pjpoes, either way, multiple subs can only help as long as they are not localizeable. Above ≈100Hz other solutions have to be applied.

Best, Markus
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