[audioman999]

The B100 does not a a sub out.  Therefore in order to integrate a sub into my system i need to use the pre out into the sub and then out of the sub back in to the power in of the B100.  the sub would be a B&W.  will there be a degradation of quality doing this versus running the B100 as is without the sub.

the option is just to invest in larger speakers.  currently have Totem model 1 signatures and am interested in PMC FB1i or OB1i.

Thanks

[srb]

Most subwoofers (including the B&Ws) that have L/R line inputs (a) sum them into a mono signal and (b) do not have line outputs.
 
Some subwoofers have speaker level inputs and corresponding speaker level outputs to run to the main speakers, while providing high-pass filtering to the main speakers to relieve them of having to produce very low frequencies which can result in less distortion and muddiness in the midrange and midbass.
 
The B&Ws appear to have only speaker level inputs and they are connected to the main amplifier in parallel to the main speakers.  I would have to assume that this is a very high impedance connection, similar to the REL subwoofer connection, which does not lower the total impedance on the B100 speaker outputs.  This type of connection would result in running the main speakers full-range.
 
If the B100 preamp outputs are simultaneously active when also internally connected to the power amplifier when the switches are in the "connected" position, it might also be possible to connect them to the L/R line inputs on a subwoofer, but the B100 manual doesn't mention if this is possible.  If it was, the main speakers would also be run full-range.
 
Steve

[audioman999]

I agree/understand that when in the connected position, the pre outputs are still active which would mean the speakers are still full range.

I had assumed that running RCAs out of the integrated into the sub and back into the power amp ins would have allowed me to determine the low frequency cutoff for my book shelf speakers.  and therefore not running full range.  Can anyone confirm?

Assuming the worse and the speakers are still running full range, will running the signal down through the sub and back up to the integrated worsen the "quality" of the signal.  I am assuming it must not be as pure as keeping everything within the integrated and not running a sub.

I guess this raises another question.  is there any downside to running the speakers full range and using the active pre out to the sub to give me extra bass?  i had assumed that if i could manage the low frequency cutoff to the speakers, this would have been the best.

Thanks

[srb]

I had assumed that running RCAs out of the integrated into the sub and back into the power amp ins would have allowed me to determine the low frequency cutoff for my book shelf speakers.  and therefore not running full range.

I don't see RCA line outputs on the B&W subs.  What model(s) were you thinking of?
 
Steve

[audioman999]

older model - ASW2500.  supposed to be a "musical" one.

[srb]

I am now on the same page with you.  The current line of B&W subwoofers do not have line outputs, but the ASW 2500 you referred to does.  This sounds like it will do exactly what you want it to do and because it appears to offer high-pass filtered line outputs, I would be inclined to wire it as you intended, from the preamp outputs to the subwoofer and back to the power amplifier.
 
I don't know how far away you are going to locate the subwoofer, but as long as the cables are not extremely long and are good quality with low capacitance, it might be a better tradeoff to limit the low frequencies to your speakers versus shorter cable length.

According to the manual, the description is that the line outputs would be high-pass filtered.  Per page 5 of the manual:

"The function of the subwoofer is to receive signals from the amplification chain and, where necessary for 2-channel audio, split the signal into low bass and higher frequencies and feed the latter back out to the satellite speakers. Left and right channel inputs may be combined into a single mono low bass feed to the subwoofer drive unit if required."  http://www.bwspeakers.com/downloadFile/speakermodel/DONE_-ASW2500_manual.pdf

Steve

[PRELUDE]

First of all just ask James to make sure that you can run the B100 as L separate and R connected at the same time.If so,than you can turn the switch only on one side L or R to separate mode then use a y connector

Now run a short wire back to power in and a long one to the sub.

[veloceleste]

Use a y connector from preamp out.  One set of cables goes back into the B100 amp in jacks and the second runs to the sub.  The main speakers will run full range and the sub will handle the frequencies below which you set the frequency control at on the sub. This adjustment, along with the level control, (and phase adjustment if the sub has one) requires some trial and error to get the smoothest integration of the sub with the main speakers.  This works if you can locate the sub relatively close to the B100.  You also introduce the risk of the interconnects introducing some hum along the way.

[audioman999]

Thanks for the advice. If I understand correctly, the desired setup is to keep the speakers at full range and adjusting the level of bass for the sub to handle.

1  do the adjustments on the sub allow you to control the amount of bass going back to the speakers?

2. If keeping speakers at full range, can I not just keep the amp "connected" and run a line out from the prez if they are always active.


James - can you confirm that pre out are always active even in connected mode.

Thanks again.

[James Tanner]

Thanks for the advice. If I understand correctly, the desired setup is to keep the speakers at full range and adjusting the level of bass for the sub to handle.

1  do the adjustments on the sub allow you to control the amount of bass going back to the speakers?

2. If keeping speakers at full range, can I not just keep the amp "connected" and run a line out from the prez if they are always active.


James - can you confirm that pre out are always active even in connected mode.

Thanks again.

Hi - yes the pre-out is always active.

james

[audioman999]

Great Problem Solved.  Now to properly integrate into my system.

[niels]

Why not use the speaker level inn on the subwoofer? See the REL netsite for details, in this way the sub receives the exact same signal as the main speakers do. Just run an extra set of cables from the speaker posts or from the speakers to the sub.
Let your main speakers run as they do now, full-range and let the sub add weight at your preferred frequence, with some larger speakers you will need a very low frequency and not all subs have settings that low.
For instance, Stereophile used an REL Strata III sub with small Aerial 5 speakers and found  a setting of 27 hz to be perfect.
For a beginners setup, put the subwoofer in your preferred listening position and crawl along the floor to find the place where you have the highest gain, this is the place the sub sub should be placed, normally its in a corner with the subs driver facing inward in the room. I mean, if you place the sub in your right front corner, the subs driver should face to the left. (For those subs that do not have a driver facing down into the floor.)

[audioman999]

I am still confused as to how to hook up the sub to the speaker posts on the B100.  What type of cable, connection would i need to use?

[Levi]

If your sub comes with a speaker level input, I would simply follow the direction from the sub manufacturer. 

[niels]

I am still confused as to how to hook up the sub to the speaker posts on the B100.  What type of cable, connection would i need to use?

Use any cable you have lying around, or are willing to pay for, it doesnt matter. Connectors? Up to you, I dont use any, just bare wire, but you can use spades if you want.
Instead of hooking the sub up to the amp you can also hook it up to your speakers terminals if thats easier for you.