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U77/5AR4 reissue is a winner

It is my pleasure to report the full wave rectifier U77/5AR4 is an unqualified success. I have been using a pair for some months and in
comparison to old stock Mullard, Amperex, and others. The U77 are as
far as I can tell in no way inferior to OS tubes. It was kind of a
shot in the dark for me. I thought if New Sensor has the confidence to
label their own tube U77 they must have supreme confidence in it. My
trepidation came from previous 5AR4 issuances that worked but were
lacking in one way or the other from a sonic perspective.

At long last I can say there is a 5AR4 of current manufacture that sounds superb - at least to these ears.

Sections in my 4 samples are closely matched if not identical.

The musicality of OS Mullard/Amperex is sustained. At long last I am
able to say this.

Finally, a 5AR4 that comes up to the mark.

The U77 also stand up very well indeed even against the Western Electric
422A in direct comparison.

I continue to be somewhat amazed by this tube.

If you have a treasured stash of OS/NOS rectifiers and have been worried
that these are irreplaceable in terms of performance and listening pleasure I think you owe it to yourself to try the U77 for yourself and stop fretting.

In full disclosure my source for these tubes was a retail purchase from
McShane Engineering. Thanks, Jim. Thanks too for the extra care as in
noting transconductance of each section and the foam peanut inside the
boxe to stabilize each tube in shipping. I appreciate it.

I also acquired 4 KT-120 for another project not yet completed I have
been working on since 2003 the end of which is now in sight. Details
will be forthcoming at the proper time.


This post is made possible by the generous support of people like you and our sponsors:
  Kimber Kable  


Topic - U77/5AR4 reissue is a winner - elektron 08:31:11 06/22/14 (11)

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