bad salesman advice - sub cross-over (1 Viewer)

[russell>b]

OK got some advice from a home theatre shop that does not seem to make sense:

A Luxman LR 280RX 7.1 receiver

I have: welling speakers welling.com.au

Front L&R towers: Welling Century 8-F : 6 ohm , 30-150W , 40-20000HZ
Rear Towers: Welling GA 8283: 6 ohm , 50 - 120W , 50 - 22000HZ
Front Center: Welling: 5C: 6ohm , 30-100W , 45-20000HZ
Left and right center rear are some outdoor SMALL 100w speakers (only ones not matched)

SUBWOOFER: Welling WS10 10" active sub , 120W RMS 40-120HZ

I don't know the cross-over/rollover freq that the receiver rolls from the fronts to the sub ? I assume it's somewhere between 80-100 HZ from what I read ? lets call it 80HZ for the purpose of this discussion.

The saleman said to set ALL speakers to SMALL on the receiver, set the sub crossover ON THE SUB to about 30-40 HZ and turn the volume up to about 90%

First when you set the fronts to SMALL on the receiver does it direct all bass to the sub or just bass below the crossover freq of 80HZ and still send bass above 80HZ to the fronts ?

2nd if the sub corssover control is set to 30-40HZ (as the salesman suggested) does this not mean that the sub will MISS all bass between 40-80 HZ ????

THE RECEIVER: I have read that if you have a DTS/EX receiver that the receiver controls ALL BASS going to the SUB and therefore you should NOT USE your SUBS crossover control ie. set the sub crossover control to the highest freq, in my case 120HZ and let the receiver control the BASS crossover ?

LASTLY should I set my fronts to large seeing they are towers ? and if I do does the receiver stop sending the BASS to the sub or does it send it to both ??

I know its a lot of questions and thanks for any responses...

 

[Wayne A. Pflughaupt]

Russel,

Correct. However, if you wanted to utilize the sub’s crossover you could send a full-range signal to it from the L/R pre-amp outputs. Of course, this would mean you’d have to set toe front speakers to “large.”

Regards,
Wayne A. Pflughaupt

 

[Jason GT]

This is an interesting bit of advice. It's uncommon but may not be completely without merit.

Typical crossover advice is to set the AVR to your crossover freq, run speakers small and disable (set as high as possible) the crossover on the sub.

What your salesman is telling you is basically to use the AVR for bass management, but to use the sub's crossover to flatten a hump in its response. This will attenuate most sub response but should make it flatter. He tells you to set volume at 90% to compensate for this attenuation.

My thoughts: I should experiment with this a bit more on my sub -- and you may wish to too (playing with the xover to flatten sub response).

 

[Brian Fellmeth]

Jason makea a great point. There may be a method to his (the salesman's) madness.



No, you won't miss it as Wayne said. It will just be attenuated relative to 30 Hz which in some circumstances might be a good thing.