On 06/09/2010 20:48, Ian Bell wrote:
Andre Jute wrote:
Time to return to tech-talk.

In a modest-sized room (by horn standards anyway) I want to rig up a
singleton of my modded semi-Fidelio bicor horns for Lowther PM6A. I
thought I'd do the monoing in a specially made 1 metre cable between
the CD player and the power amp.

The QUAD CD expects to see at least 10K impedance on its outputs.
Output of the CD player is 2Vrms and about 0.5Vrms of that is required
to drive the amp to enough power to handle the horns, so high value
resistors can be used in the monomaker if there is any advantage to be
gained.

However, the sound is NOT intended to be reprocessed as stereo
downstream (home installation, not studio); if I want stereo again,
i'll just plug in a stereo cable.

The pot on the integrated amp is probably (the board won't be here
until Tuesday and i can't read the spec on the piccie) 50K Alps but I
can replace it with a DACT of which I have a good selection of values.

So what value resistors would you use for monoing?

How many? Only two, or three?

With your choice of values, what can I expect to lose from the monoing
in bandwidth as distinct from gain?

Andre Jute
Visit Jute on Amps at
http://www.audio-talk.co.uk/fiultra/
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#

I would use 3 resistors, all 10K. I think you can guess how to wire
them. The important thing is to place them at the amp end.

Can't guess how to wire them to give the desired attenuation.

--
Eiron.