Powered Sub to 2 Channel ?

So If I have a standard amp (2 channel w/ a and b speakers switches) with a preamp (these are adcom), and I wish to add a 'powered sub', what is the best way ? b speaker output to sub ? tape out from preamp ?
Thanks

PS I will skip the sub over upgrading the amp.....

Assuming your sub has two line level inputs, the way I did this was to simply use two "Y" connectors between the preamp and the main amp. One leg to the main amp and the other leg to the powered sub's line level inputs.

I use the monitor out I tried it with the tape out but I lost control over the base output via the remote (receiver) using the tape loop....in other words as I ajusted the volume of the source (ie LP, CD) the sub volume remained the same...using the monitor loop your sub will increase or decrease as your front two speakers are adjusted.

Peace, Pogue

If you search for a sub with BOTH line level inputs AND outputs (such as thepogue's, Monitor Audio ASW 210), you can run interconnect cables (rca) from the preamp's L + R outputs into the sub's line level inputs, then... run interconnect cables from the sub's line level output to the L + R input of your amp (and of course, speaker wire from your amp to the speakers). You can use the Sub's variable crossover to find a frequency that integrates the sub and mains together: The sub will pick up the low frequency information below the crossover point while the high pass filter will send the rest to your amp so that it is only amplifying the information above the crossover point, thus making it easier to drive your main speakers. This is just one option for subwoofer/speaker connections, but beware -- most subs have line level inputs -- not all have line level outputs.

Q