Question About Bass Management

[spurxiii]

Hi all, firstly I want to thank you guys for the great advice which helped me in choosing my speakers since I am new to all this. I've recently purchased a set of B&W DM602 S3 and an LCR60 centre which I'm using with a Richtor Thor MkIV Sub and a Yamaha AV Receiver. The speakers haven't been broken in yet but it sounds great to me. When I first heard the speakers at the dealers I thought they were a little bit on the bright side, but bringing it back home there was no hint of any brightness. I think it is due to the showroom being all tiled and glass everywhere. Anyway back to the Bass Management Question:

1. I currently have the crossover on the subwoofer at maximum and the receiver's crossover set at 80Hz and have played around with this setting but 80Hz sounds best to me at the moment. What should I be setting this crossover to because the DM602s go down to 49Hz ± 3dB on reference axis and the LCR60s go down to 70Hz ± 3dB on reference axis?

2. Does the 80Hz setting mean the speakers will cut out at 80Hz and the sub kicks in? Meaning I will lose the 30Hz from the fronts and 10Hz from the centre.

3. I currently have all the speakers set as small and the receiver outputing the bass to both the front and subwoofer. (there is an option to have bass output to subwoofer only - should I use this setting instead?) I've read in a few places where they say that outputing the bass to both sub and fronts may cause damage to your speakers. Is this true? I think the sound is more fuller and rich with bass outputting to both sub and fronts.

Thanks in advance for any help.

[norpus]

Hi all, firstly I want to thank you guys for the great advice which helped me in choosing my speakers since I am new to all this. I've recently purchased a set of B&W DM602 S3 and an LCR60 centre which I'm using with a Richtor Thor MkIV Sub and a Yamaha AV Receiver. The speakers haven't been broken in yet but it sounds great to me. When I first heard the speakers at the dealers I thought they were a little bit on the bright side, but bringing it back home there was no hint of any brightness. I think it is due to the showroom being all tiled and glass everywhere. Anyway back to the Bass Management Question:

1. I currently have the crossover on the subwoofer at maximum and the receiver's crossover set at 80Hz and have played around with this setting but 80Hz sounds best to me at the moment. What should I be setting this crossover to because the DM602s go down to 49Hz ± 3dB on reference axis and the LCR60s go down to 70Hz ± 3dB on reference axis?

2. Does the 80Hz setting mean the speakers will cut out at 80Hz and the sub kicks in? Meaning I will lose the 30Hz from the fronts and 10Hz from the centre.

3. I currently have all the speakers set as small and the receiver outputing the bass to both the front and subwoofer. (there is an option to have bass output to subwoofer only - should I use this setting instead?) I've read in a few places where they say that outputing the bass to both sub and fronts may cause damage to your speakers. Is this true? I think the sound is more fuller and rich with bass outputting to both sub and fronts.

Thanks in advance for any help.

Sounds to me like you have set it up perfectly and understand it well. Well done!

All speakers to small and 80Hz crossover on the avr is what I use (yes even with the big B&W's)

I send the lfe and all redirected bass to the sub only - it sounds best and makes the mains clearer too

Btw, the 80Hz crossover is not a brick wall - there will likely be a 24dB/octave slope meaning your sub will play some stuff above 80, maybe to 120 and the other speakers will play some signal below 80 tapering off almost completely say at 60. It's all good and well managed

[Thudd1503560234]

1. ...but 80Hz sounds best to me at the moment.

There's your answer on that one

2. Does the 80Hz setting mean the speakers will cut out at 80Hz and the sub kicks in? Meaning I will lose the 30Hz from the fronts and 10Hz from the centre.

-3dB means that the speakers are producing half the volume at that frequency than they would at a higher frequency referenced at 0dB. So if you had a brickwall filter that cut off everything above 50.00Hz and the sub took over at exactly 49.99Hz, it'd sound weird because there'd be a big hole between 80Hz (or wherever they start rolling off) and 49.99Hz when the sub suddenly roars into life.

Real xovers however don't cut off at precisely the frequency you set but roll off at a certain rate depending on the crossover. So if you set the xover at 80Hz, at 60Hz your speakers are still producing output, while the sub is still pumping out at 100Hz, albeit both at reduced volumes (these values are arbitary btw just to illustrate the point). The trick is to find the frequency at which the sub blends seamlessly with the speakers - and if that means you "lose" frequency range from some speakers than so be it, because in reality you're not losing anything, you're gaining better sound.

The other thing to consider too is that it takes a lot of power to produce low frequencies, so if you can take the low frequency load off your speakers and onto the sub, your speakers will be able to handle the rest of their frequency range that much better; so again even though you might "lose" 30Hz from your fronts, the end result is that they perform better at all the other frequencies.

[spurxiii]

Thanks for your answers. I'll leave the crossover at 80Hz and change the bass output to subwoofer only. although the sound was more full with bass output on both subwoofer and fronts I did notice that the fronts sounded clearer with the bass only going to the subwoofer.

I'm glad to hear that the 80Hz crossover setting is not like a brick wall.