Tonally I find them QUITE attrative without being colored...maybe it's that triode sound I love. I've replaced the 10 coupling caps per amp; mine sound cleaner throughout the MR and treble than they did before the cap change. They image quite largely yet precisely, due mostly I think to their 'mononess'. With 11 tubes per amp, they produce plenty of heat, but that's why God made airconditioning for us desertrats! The bias is stable after the tubes break-in; I tweak mine at the end of every listening session but just because I'm a tweak! I've also replaced the output tubes with the GREAT-sounding-but-highly-affordable Penta/Shuguang KT88SC ($29 each), but not because I had to...I'm just a tweak!
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