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Old 12th Jan 2021, 10:19 pm   #7
Herald1360
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Join Date: Feb 2007
Location: Leominster, Herefordshire, UK.
Posts: 16,526
Default 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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