To bridge or not?

[mr rusty]

we've just acquired a cerwin vega sub-15 subwoofer to complement our intense 152's. Intend to drive the sub15 with the spare numark dimension3 amp. the sub is rated 500W program 1000W peak and is 4ohm. The amp is rated 450W + 450W stereo into 4ohm or 1350W mono bridged into 4 ohm.

What do you guys reckon is best - run this single sub off one channel or bridge the amp?

[Danno13]

I'd run it bridge. If you use one channel, you've got no headroom, whereas bridged you've got plenty! Plus, i'm sure I've read somewhere that its not a good idea to run just one side of an amp.

Although.. running 4 ohm bridged is the equivelant of running 2 ohm stereo.. so probably best to check if anyone else has ran this particular amp in this way. Since its a fairly budget amp, it might not be a very good idea.. and may get way too hot.

[TonyB]

Personally I wouldn't run it in bridged. Although the Numark states it runs at two ohms, I wouldn't trust it for prolonged periods. Using 1350w to power a 500w speaker is also a bit excessive and could well damage the speaker if the volume was too high.

[mr rusty]

thanks - <sarcasm> so far we have a consensus then!! </sarcasm> :)

Prob try it unbridged and see how I get on. As long as the amps not clipping I think it should be the best option. Although it does say the sub has an internal thermal cutout if its overpowered I don't think I want to test it!

[gillo]

thanks - <sarcasm> so far we have a consensus then!! </sarcasm> :)

Prob try it unbridged and see how I get on. As long as the amps not clipping I think it should be the best option. Although it does say the sub has an internal thermal cutout if its overpowered I don't think I want to test it!

keep it that way the that cerwin vega is rated at 250 rms so running it off one channel your supplyin it with nearly twice the rated power already. just keep the other channel gain which isnt being used to 0. also this amp isnt stable doing 4 ohm bridge.

[mr rusty]

Hi Gillo, thanks for the info. Slightly intrigued by your comment that the sub-15 is rated 250W RMS as the operation manual states:


The sub-15 is rated at 500W continuous program. This means that it can be safely used with an amplifier rated 500W RMS as long as the amplifier clip light is not lit most of the time.

Still trying to get my head round amp and speaker ratings! Are you saying that this speaker rated 500W program & 1000W peak, is also to be rated 250W RMS. I understand where the RMS bit comes from, but would have thought continuous program *was* RMS.

BTW, this is the "original" sub-15, not the later sub-15 mk11 which appears to be rated by CV 350W/700W instead of 500W/1000W

[gillo]

Hi Gillo, thanks for the info. Slightly intrigued by your comment that the sub-15 is rated 250W RMS as the operation manual states:



Still trying to get my head round amp and speaker ratings! Are you saying that this speaker rated 500W program & 1000W peak, is also to be rated 250W RMS. I understand where the RMS bit comes from, but would have thought continuous program *was* RMS.

BTW, this is the "original" sub-15, not the later sub-15 mk11 which appears to be rated by CV 350W/700W instead of 500W/1000W

rule of thumb whenever buying speaker look for rms rating, like peavey speakers look at the ratings e.g. 350 rms 700 program (contiuous) 1400 peak:) it may be that any 250 watts rms speaker can handle 500 watts rms as long as its not distorting and the clip light is flashing it all comes down to the manufacture and amps you use. the driver in that bass bin will be the equilavent to a 1000 watts rms soundlab driver! thats because it is being cerwin vega it will be a really efficent driver:)