Mullard CV4004 / 12AX7 British New Old Stock Kevin's Stash / No Cryo Reviews

4.6 Rating 9 Reviews

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909.931.9686

Email:

joel.m@upscaleaudio.com

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2058 Wright Avenue,
2058 Wright Avenue
California
91750

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Edward Dabrowski

Verified Reviewer

Author didn't leave any comments.

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Posted 1 year ago

Michael Schutter

Verified Reviewer

“Huge improvement on a McIntosh MA252!”

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Posted 4 years ago

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Posted 4 years ago

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Posted 4 years ago

Ian Richardson

Verified Reviewer

“I’ll try to put this as civil as possible as my other review was never posted. I bought $1800 worth of tubes from Upscale as a first-time customer. $800 of which were CV4004’s, “Kevin’s Stash/no cryo.” What I spent is of less importance than the fact that one of the tubes was simply a dud. It happens. It wasn’t a problem as Sean at Upscale was very helpful in trying to get me a replacement. All I asked was surely a tube this weak and noisy had to be pulled from the buffer section. But Sean’s boss simply said, “Transconductance is a measurement that varies,” as if everyone who buys from them is too dumb to recognize a weak, noisy tube. The others were acceptable, but with this one tube I just threw $200 to the wind. The manager told Sean no replacement. Mind you I never spoke with Kevin, and I don’t think anything nefarious was involved. Only that you should be prepared to risk losing money on the CV4004. They must be down to the dregs on these. All the Popes and La Radiotechnique and even the 6201 Mullards I bought were solid tubes. Very solid. But so it goes. Again, Sean was most helpful. Whoever told Sean to tell me my “high-grade” cv4004 was weak and noisy because “Transconductance varies,” just screams “you’re stupid, and we’ve got your money.” Sorry if this is civil as I can get. I don’t expect it to get posted, but I’ll keep trying. Everything was great except for one tube, and one guy. The rest was solid.”

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Posted 4 years ago

“At the first listen in my Luxman MQ-88uSE I thought the CV4004 was a little laid back in the mid-range, but as the tube accumulated some playing hours the mids opened up and came forward. I still don't even have near enough hours to hear the full blossom of these tubes, but it was evident from the very beginning that they have layer upon layer of extraordinary detail. The Tesla input tubes I was using are very good, but the Mullard just take the performance to another level.”

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Posted 5 years ago

Robert Mayer

Verified Reviewer

“Bought one of these along with a pair of NOS Mullard 6201's, also from Upscale to replace the new new manufacture Tung-Sol's that came with my Bob Carver Crimson 275 because they were a little harsh for my tastes. This combo of Mullards made a very noticeable improvement in both the bass and mid range. The bass now has more bottom end and some real grunt to it, and the mid range gained some extra presence which has steadily increased and become even more revealing as they get some burn in time on them. I'm constantly noticing sounds of instruments in recordings that I'm very familiar with that never stood out before. These are some really sweet sounding tubes.”