2. home-theater
  3. 1423079143

HT cross over question

I am trying to integrate an analog 2 channel stereo plus a sub using a pass through pre amp and two channel amp with my Yamaha HT reciever.
Basically sharing the mains and sub between the two systems.

So... I am not using the LFE output of the AV receiver. I have the LR signal going pre out ... passing through the Audio Research pre amp and then output from the Audio Research as single ended L and R to the line level inputs of the sub... The sub x over is now at 60 Hz... then the sub output is High pass filtered at 80 Hz and going into the single ended inputs of the classe power amp.

I have the Priority of two channel over HT and so the sub's crossover set at 60 Hz and the volume complimenting my Kef 104.2 LR main speakers using the balanced side of my system.. set by ear ... and may be changed over time.

My question is... what should I set the AV cross over?

I have set all of the speakers to SMALL and the AV receiver is set to mix all low frequency info and output to the LR mains (no sub woofer defined for the AV receiver). Currently the AV receiver x over is set to 80 Hz.

My understanding is that multichannel low frequency info including the LFE stuff is digitally filtered at 80 hz in all channels and then all of this info is combined and output full signal to the LR mains and thus sent to my sub. Where the Subs analog filter is sending the 60 hz an lower info to the sub and the 80 hz and above info is output to the LR main speakers.

It would appear that I have created a hole between 60 and 80 HZ...

What should I do to start... raise the sub xover to 80 when I switch between systems?

What should I listen to to optimize these filter settings?

Do I have to break down and get an spl meter?

If I use the balanced side of the system... the AV reciever is sending the full range plus lFE info out through LR which is then ampliied and sent to the mains.. while the sub sees that signal and filters at the cross over (currently set at 60 Hz) Seems like I wind up with too much bass summing here and the Kefs are trying to reproduce all of the boom boom of a theatre track as well.

I am confusing myself! Is there an OK solution?
tcatman
tcatman OP
57 posts
 
HA... talk about my blind spots.... Thanks for pointing this one out...

Once upon a time... I read that using the speaker level inputs to a sub was the worst possible way to feed them. I thought of the speaker level terminals as a relic from the distant past... Consequently... I never thought of the AV solution using the speaker level inputs at all ....much less in this way.

You are absolutely right... by using the HT bass processing and the LFE output of the AV receiver for movies... I should get rid of the congestion I hear right now in the movie soundtracks....

I found this box
Russound AB-2.2
Tabletop A/B selector

which has a max power spec of 150w RMS... The power handling should be fine (Its a 200 W amp)... This box will disconnect the sub speaker level inputs... then the AV receiver does the LFE thing as designed for movies... or any 2.1 listenting I want to do with the AV reciever... stupid simple.... ssshhh.
I will let you know how the theater sounds.
Thanks for the new way of looking at it.
tcatman OP
57 posts
 
AV
One final question.... I have two crossovers in play now... the AV processor is set at 80 HZ... The sub cross over is set for 80 Hz using the speaker level inputs for music as DB recommended and I concur.. ... (No high pass cross over used)

Is there any problem with this set up of the two cross overs?

Normally... I would turn the sub cross over off... ie 200 Hz. Am I supposed to raise the HT Receiver cross over to something higher when the sub cross over is set for 80hz?

Hopefully the Sub volume level that works for the speaker level inputs and music will also work for the HT receiver and the LFE line level input channel.
Thanks
avgoround
287 posts
 
Well just remember, you're not really using 200 watts of current at the box, since you're really only "taking a signal" off the wires at the sub!..not powering the sub with speaker wire connections. So, I don't believe you're actually drawing current there.
And I would 100% state that using speaker level subwofer connections is 100% better for simply bass signals to the sub, than it is using speaker level connections through the subwoofers internal highpass crossover, and out to the satalite speakers, driven that way!!!! Same can be said for line level connections to the sub, filtering out to the sats, as well.
Just never heard one setup where the sound from the mains was anything special going through the likely cheap crossover parts thrown into a powered subwoofer, as an "after thought". Wouldn't do it..
I like my earlier suggestions, yes.
Hope it works out for you
avgoround
287 posts
 
yes, typically, if your using two crossovers in a subwoofer's path, usually, you turn the later all the way up and out of the way. The one in front gets set to the 80hz. So, connected to the AV pre, you set the pre to 80hz, and sub to 200hz, and so forth. With parallel speaker level connection, however, id run full range from analog pre amp and then set sub cross at wherever main speakers naturally roll off, usually...otherwise, set to 80hz if filtering mid/highs as you first suggested you connected things.
Main thing is really not to set two crossovers in the same path at same location!! Weird phase issues can happen. That's the main issue. So one you will need to set high, and the other about where you want it set, in this case, the discussed 80hz location, and you shouldn't run into any problems associated with two crossovers in front of one another.
tcatman OP
57 posts
 
AV
Does it make any difference if I switch the low level line inputs..... eg HT Amp LFE output with the Preamp out .... going into a switch and the selected output going to the sub LR line level iputs.

Or...is there some advantage to using the speaker level inputs.

(I can't think of a reason)
More to discover