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Slowhand,
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Mine is in the 6sn7 format and it is just wonderful (using Tungsol, Black Glass, Round Plates).
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I just can't imagine with all we do (spend) that it would be worth it to try to save on the tubes at this level.
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Having said that, I have not heard both configurations. You would have to hear both in the same system to be able to discern the real difference.
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I would ask Mick which set up sounds best with the best tubes in place and assuming your budget will allow (even it won't), go for what will be the best sound.
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Thanks for starting all of this for all of us.
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