Re: Post Amp- Pre Amps

From: Christopher Bogart (cbogart@netscape.com)
Date: Fri Oct 02 1998 - 18:06:57 EDT


Or you can just by line out converters which you wire your speaker wires from the
stereo to. They convert that to a line level RCA out, and the better ones allow
you to adjust the gain. Distortion is minimal and with a good amp this works well.
Hell, some good amps take speaker levels as inputs.

Have fun. Stereo stuff is a blast.

Bogart

>
>
> Figure out your maximum watts out, get a 4 ohm dummy load that can handle
> those amps. Connect a parallel high value load (I'd use a variable resistor:
> but must have a min ohm value of greater than the dummy load) resistor also.
> Take the tap out of the parallel resistor and hook it to whatever device you
> need the pre-amp outs for. Your main power will dump into the dummy load and
> the high value resistor will "monitor" the output at a much decreased level so
> that you can use it as a "Pre-Amp". Diagram as follows:
>
> IN (+)
> -----+-----+
> | |
> [4 ohm] [~10ohm - 20K ohm]
> [dummy] +---------- Pre-Out (+)
> [load] [Variable Resistor]
> | |
> -----+-----+---------- Pre-Out (-)
> IN (-)
>
> The dummy load will get VERY hot at high power settings. It's better to
> set your max pre amp aat a lower than max power level with the variable
> resistor, and then control the volume as usual from the source. I make no
> guarantees that this won't absolutely waste some high-end or cheap system. I
> do know that it works for low to medium power applications. (1-20 watts) Use
> at your own risk! ^_^
>
> Shaun H.



This archive was generated by hypermail 2b29 : Fri Jun 20 2003 - 12:10:32 EDT