Tube rolling results:
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First off, thanks ever so much to Ecclectique, Bwhite, Asa, and Jazzdude for all your help and advice in recommending NOS tubes for my Cortese.
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The results of the NOS tubes have been nothing short of stunning with regards to the enhancement of the bass control, sound staging (expansion of and delineation), detail without giving up warmth / emotion, more life like sounding instruments, and much more musicality. I loved the Cortese with the stock tubes and now with the NOS in place and broken in, the listening has become an overwhelming and tireless experience.
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I rolled the following tubes into the line stage section of my Cortese:
Nos Neotron 6SN7's
Nos Mullard EL 37's
NOS 5AR4 Philips Miniwatt Holland Metal Base NOS 1957 Tubes
They were all quite expensive, but in the end well, well, worth every penny.
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I just ordered a pair of NOS Tungsol 6SN7 Black Glass round plates and will let you all know how they stack up against the Neotron 6SN7's after they arrive and are broken in.
It took a good solid 200 hours of continuous running time for the NOS tubes to fully break in before they really showed what they could add to the sound (EL 37's took a particularly long time).
For those of you rolling NOS, give them a bunch of hours before evaluating. The improvement from break in is huge. The value for the extra money invested in NOS is clearly available.
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