bad partsexpress amp?

[nayr2]

I just recieved this 250watt partsexpress plate amp:

http://www.partsexpress.com/pe/showd...number=300-794

it seemed to work ok on initial test, until I turned off the speakers and listened to the sub itself. Holy ****, that is disgustingly bad leak-through.. almost as if the crossover is inactive. The crossover does seem to "work", but only by a few dbs.

With the crossover set to 40hz, and at *low* listening volumes, I can hear sounds up to 3000+hz.

Has anybody expreienced something like this before?

[BAM]

Did you plug into the LFE Direct input?

If so, then the problem isn't the amp, it's you. The LFE Direct socket bypasses the crossover, so it can use the Dolby Digital decoder's preset crossover frequency, which is done by every dolby digital receiver. Then, the receiver often has the adjustments for the crossover. Try plugging into either the left or right RCA plug (the white or red ones). This will just sum the inputs into one mono input for the subwoofer but this time the crossover will be in the signal path.

[nayr2]

I have tried the speaker wire "high level inputs" as well as using the pre-out on my amplifier. This is for a stereo setup, I don't have a reciever so no dedicated LFE channel.

[simon5]

Try it with speakers before making your mind.

If you play bass at 90 dB which is not that high, since it's a 12 dB/oct x-over, at 1 kHz you might be still at 40 dB if the subwoofer is a bit peaky on the top end. You will hear the 40 dB midrange quite easily if your room is quiet, but if it's masked by 90 dB midrange played by your speakers, then you won't hear anything.