On Tue, 23 May 2006 23:19:19 +0100, wrote:

Hi,
I'm setting up a parallel configuration of 23 sets of Sony SRS-A205
active speakers in work to be fed from a streaming radio feed from a
PC. The input impedence of the amp in each active speaker is 4.7kOhms
(at 1Khz). The speaker wire runs approx 400 meters in total. I gather
that I don't need a substantial power amp between the PC and the
speakers considering the speakers have amps present within the speaker
boxes, but do I need any kind of amplification function between the PC
audio out and the collection of active speakers or will the PC sound
card be able to handle sending adequate signal levels to the 23 sets of
active speakers over the 400 meters of speaker cable. The speaker
cable is ordinary # 16 gauge multistranded. Any ideas would be
appreciated. Anybody know the maths to solve this question?

Chris.


Looks like no-one has really answered the question although Dave gave you
a big clue when he mentioned DA. DA stands for distribution amplifier
which takes your output from the soundcard and buffers it into a number of
outputs suitable for sending to your active speakers. People like Drawmer
and Sonifex make them.

You can usually get away with paralleling 2 or 3 inputs together and
feeding them from a single output if the connections are short but you
probably need a dedicated DA output for each speaker with a long cable.

Cheers

James.