Re: Crossover distortion?
The tiny audio transformers won't do the quality any favours either- compare with what're fitted to a Bush TR82 for instance. The output transistors also need to be decently matched for best results.
Take a careful look at the output stage idle current (volts across the common emitter resistor)- too little = lots of crossover distortion, too much could lead to thermal runaway! If the set still sounds crappy (rather than just tinny) with a few mA, matching is probably poor.
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