Subwoofer selection for Beosound Overture and Beolab 2500 speakers

Hi there,

Can anyone suggest a non Bang and Olufsen subwoofer for my Beosound Overture, with Beolab 2500 speakers? I have been looking at the B and W ASW600 but really have no idea what will match. The room is approximately 15m x 7m, carpet, one wall mostly glass as we have have double sliding doors, walls are made from plasterboard. I listen to a wide range of music and need to know what sized sub would suit, what design (as i hear there are many, down firing, ported and non ported etc), and what brand.

Thanks

Brian

Hello,

I do not know why it should be non B&O but would recommend you to either add a BL11 or switch from the 2500 to a pair of BL3. For such a big room the BL2500 might not be really adequate. My room is with many glass walls and about 7*8m big. The BL3 are just good for it. Any other SUB makes the setup just more complicated.

Heribert

The Beolab 2500 fill the room well, just no bass. The reason I would like a non B and O sub is because of the cheaper price, and I have all the connection to get the sub hooked up so thats no problem

The problem with an non B&O sub is getting it integrated well, as usually you lose the high pass crossover function to the satellite speakers. If you have two Powerlink outs and convert one to RCA outs to drive the sub and use the other for the Beolab speakers, the Beosound run full range, which not only lacks the advantage of keeping the bass out of them for clarity but also makes integrating the sub harder. Especially as with speakers with Adaptive Bass Control (if yours have that) the bass level of the small speakers is variable with level. 

PA B&O sub, with the Powerlink going to the sub and then to the smaller Beolabs does both low pass and high pass functions. If you use Powerlink to the Beolabs you'd have to split out the signal to RCA plugs and run it to the sub (if it has a high pass section for line level inputs) and back to Powerlink. 

If the speakers have both Powerlink and RCA inputs as some Beolabs do, not sure about the 2500's, you can go to RCAs to the sub and back to the Beolabs, which would work but the Beolabs would then not turn on from the link signal but from auto sensing an input signal. 

If you go with a non B&O sub make sure it has a line level high pass crossover, otherwise it will be harder to get it integrated. 

Hi Jeff,

Thank you for your quick and detailed response. You have to talk to me like a child when it comes to this stuff as it's not my forte'! So you're telling me that the problem with connecting a non B&O sub is that I will not have control over the frequencies going to the sattelite speakers and the sub? So I will be sending all frequencies to the sub, where I only want the lows, and all frequencies to the satellites where I only want the mid-highs? This may be crude but I figured I would just lower the bass input to the satellite speakers, then adjust the crossover on the sub to filter out the mid-highs. Is this possible??? 

Would the controls on these subs allow me to integrate them somewhat or am I better off saving the extra cash to get a B&O?

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Thank you again for your help,

Brian

Have you tried playing with the bass/treble/loudness adjustments?  I have mine in a room of similar size at waist height flat against a wall (better bass response) and it puts out plenty of bass.  I think the speakers sound terribly flat with all settings on neutral, compared to a conventional amp and quality bookshelf speakers on neutral settings.

Brian,

Most subs that have their own amps have variable low pass crossovers to filter out the high and mid frequencies. Usually you get three controls, level (adjusts the relative volume of the sub), crossover freq (adjusts where the upper freq limit is), and phase or polarity, sometimes the sub winds up in or out of phase with the main speakers depending on things like the crossover frequency and the position of the sub relative to the speakers, so flipping it one way then the other to see which works best is easier than rewiring it.

So, most all subs have low pass filters, including the B&W you link to. The issue is filtering out the bass to the smaller speakers, which releaves them of load, makes them clearer and such. Do your B&O 2500s have both Powerlink plugs and RCA plugs on them? I have to say it's been a while since I've seen a pair and don't know.

If they do, you can get a Powerlink to stereo RCA plug adapter plug, run two RCA wires to the sub (if it has a high pass crossover), then run two RCA wires back, one to each 2500, and you'll get filtered audio to them with no lows in it. It is also possible to do this with the Powerlinks but it's more trouble as using that input the speakers usually won't autosense and turn on without the powerlink power on signal.

Some subs don't have high pass filters for the main speakers, some do and they are variable, and some have fixed frequency high pass crossovers and variable low pass ones. It's not always straightforward, usually you set the high and low pass to the same freq, but sometimes to make it sound smooth in the transition you wind up setting the low pass at a different frequency than the high pass, depending on the room acoustics. Integrating a sub can take a while and a fair amount of tinkering, setup, listen, tweak, listen some more, make a couple of measurements, listen, tweak, etc.

 

Hi Jeff

Thank you again for the valuable information. I plan to purchase the asw600, and trying both wiring set ups to see which sounds better. The 2500s do have a powerlink cable so I will be able to connect the subwoofer that way.

I will let you know how it sounds once all connected. Thanks again for taking the time to answer my questions!

Brian