Multiple Small Subs - Geddes Approach

[markus76]

From what I've heard there're audio engineers that mix low frequency content even to the surrounds. Movies are remixed for DVD or Blu-ray. The same speaker models for all 5 or 7 channels are used.
An AVR should do the summing. Klein + Hummel does it in their active subwoofers.

Best, Markus

[gedlee]

Originally posted by markus76
From what I've heard there're audio engineers that mix low frequency content even to the surrounds.
Best, Markus

This was hotly debated over at AVS and the conclusion was that it was rare. Does happen, but rarely.

[markus76]

So how would the signal routing look like? In case of filters on the mains a simple y-cable won't make it?

Best, Markus

[gedlee]

Markus

I don't understand. I gave you the routing and I don't use or recommend filters on the mains.

[pos]

Hi Earl,

Do this service only work if you provide the subs?
Would it be possible to use any sub, or do you need to know the specs of the subs to adjust the settings?

[gedlee]

I could do this for any subs, but whats the carret for me in that case? To charge for the service it would have to be pretty steep, so much so that I don't see it as worthwhile. Maybe I'm wrong. What would you pay for such a service?

[randybes]

Earl,

When do you think you will post on your website, the parameters and cose of your sub package?

[markus76]

Originally posted by gedlee
Markus

I don't understand. I gave you the routing and I don't use or recommend filters on the mains.

So the routing with two speakers or stereo should look like this?



With more than 2 channels it's complicated even if an AVR is capable of routing bass to speakers and sub at the same time. There will be signals for which the whole thing is not calibrated for, e.g. LFE played back by the subs but not by the mains.
To avoid this you'll need an AVR that is capable of feeding the low frequencies of all channels to the sub out and back to all speakers—the LFE would need to be routed to every speaker too.

Implementation would be much easier if your code could work with fixed HP filtered speakers. Then nearly every AVR could be used.

Best, Markus

[gedlee]

Markus

That routing is basically correct, although one could just as easily take the L&R out of the DCX unit, but I know that audiophiles have issues with that. What you show is what I do.

It is my understanding (from an alternate site) that ALL AVRs will put the LFE onto any channel that is listed as "large" if the "No Sub" option is set. It's a standard function of the chips. This then covers 90% of the problems and if there is no unique center channel bass then all the bases are covered.

[markus76]

Originally posted by gedlee
It is my understanding (from an alternate site) that ALL AVRs will put the LFE onto any channel that is listed as "large" if the "No Sub" option is set.

That's correct. But how do you get the sum of all channels into the DCX? You would need an AVR with preamp outs and a mixer.

Best, Markus