[mcjasonb]

i'm now seeing 7.2 receivers. i'm assuming the .2 means it has two subwoofer outputs?


is this right?

 

[MichaelJHuman]

Most receivers offering two LFE/bass outputs provide two outputs containing the same signal. People use Y cables to accomplish the same thing. There might be advantages to two outputs - a Y cable is forcing a line level output stage to drive two amp inputs. I have never heard anyone complain about issues with Y cables though.


A few receivers, I think, can process both outputs differently. I assume they can apply different room correction to them. I was thinking the Yamaha RX-Z11 might have done something like that, but I could be wrong.

 

[mcjasonb]

if it can EQ and delay each output (each subwoofer) independently that's cool. if not if seems like a waste.

 

[M Code]

The 1st AVR with dual subwoofer outputs was the HK 745 introduced almost 4 years ago. By using its proprietary Ez/Set EQ software written in-house by Harman/JBL engineers, the DSP would output 2uniquely different sub/LFE streams. Basic idea was to increase the width of the listener's soundstage and to balance the low frequencies heard @ the listerner's position...


Though some may argue...

If the AVR's EQ software doesn't get the low frequencies rite to compensate for the listening room's resonances and peaks, most likely then the rest of the audible spectrum will not sound rite. The majority of this research for multiple subwoofers was done by Dr. Floyd Toole and Todd Welti going back to 2002, check the AES preprint index if you want more information. Also my understandng is that in the new HK 7550HD, its dual subwoofer EQ software has been upgraded significantly..


Just my $0.025...

 

[mcjasonb]

cool, i had no idea.

 

[BNW]

Or... most sub amps contain a line level output as well as the input allowing daisy chaining of multiple subs

 

[M Code]



Quote:
Originally Posted by BNW /forum/post/16978083


Or... most sub amps contain a line level output as well as the input allowing daisy chaining of multiple subs

Cascading a single Subwoofer output to a chain of subwoofers is quite different..

As the source signal is still a single channel..

The referenced EQ software wrtitten/created by Harman/JBL's team uses the single LFE/Subwoofer source stream and then the AVR's DSP post-processes for (2) uniquely, different subwoofers outputs after measuring each listener's position...


Note that this is very different from the method Yamaha uses in their mid-AVRs, they are simply runnng (2) subwoofer outputs tied together..

This can be done very easily by using a $3 Radio Shack Y adapter..


Just my $0.025...

 

[Charles R]



Quote:
Originally Posted by M Code /forum/post/16977324


The 1st AVR with dual subwoofer outputs was the HK 745 introduced almost 4 years ago.

My old Sony STR-DA50ES has dual subwoofer output and was around before room correction was invented.

I have been enjoying it for over 10 years.

 

[penngray]



Quote:
Originally Posted by Charles R /forum/post/16978463


My old Sony STR-DA50ES has dual subwoofer output and was around before room correction was invented.

I have been enjoying it for over 10 years.

yeah but does it have individual settings (trim, EQing, etc)?



The Y-cable was invented more then 10 years ago so having two subwoofer outputs is kind of a moot point

 

[sivadselim]



Quote:
Originally Posted by mcjasonb /forum/post/16976981


if it can EQ and delay each output (each subwoofer) independently that's cool.

There are apparently a few that can. Of course, it's not really going to help with more than 2 subs.