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Hi
A comment or two about Tim's design:
You don't need both of the 100uF bipolar output caps (with their poly bypasses) as the 2 outputs of the IC are wired in series through the transformer primary. In effect you are using a 50uF cap in series with the signal which is not that good for LF. It will of course work, especially if driving into 10K Ohms or more but a larger value would be better. If you have built one up, please try it!
Secondly the input common mode being supported by the transformer, this is only partially true since even with one 'input' leg disconnected the signal will only fall 6dB maximum.
In all practical instances this is not relevent since signal levels are high and impedances low.
I don't have the time to 'knock it up' and test it but I would suggest the equivalent of 1000 uF Bipolar.
Assuming it is powered by a clean supply you could fit a 620K resistor from one supply rail to ONE of the inverting inputs which will pull the output about half a volt in the OPPOSITE polarity so that you could then use a 1,000uF or greater polarised cap (with it's bypass). This will affect the maximum headroom VERY slightly, much less than 1dB, but depending on the exact IC used this will not be significant if it is 'biassed' away from the polarity that clips first.
Matt S
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