Mullard CV4004 / 12AX7 Preamp Vacuum Tube
From our review: "The smaller plates reduce noise. They are dead quiet both electrically and mechanically. Nice thick bottles and well aligned internals also help. If you currently like the Tung-Sol 12AX7 preamp tube you will love this tube. The gain is similar but overall it is quieter and a bit warmer to my ears."
From the manufacturer: "The CV4004/12AX7 is a high gain, low noise valve with a short plate structure for reduced microphonics. Excellent for use in high gain Marshall pre-amplifier circuits where noise and microphonics can be a problem. Best for guitar amps."
The Mullard name and trademark have been acquired by the New Sensor Corporation. This new production Mullard CV4004 tube is manufactured at their Xpo-Pul factory (also known as Reflektor) in Saratov, Russia. New Sensor is an American corporation and since taking ownership of this factory has been steadily improving the quality of current production tubes.
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Warranty Information and Return Policy
Warranty Period: 3 monthsAll our tubes are guaranteed for 3 months from the date of purchase. (Any exceptions will be noted on that tube's Warranty tab)
If you receive a tube that does not perform to the manufacturer's specifications, please do the following:
- contact us to get a return authorization
- return it via regular mail within 90 days from when we shipped it, and we will provide an exchange or refund of the full purchase price of the tube.
Returns not related to warranty or defect will be considered at our discretion, and are subject to a 15% restocking fee.
We can not accept returns that don't have an authorization, are past 3 month, or are returned improperly.
These guidelines may be updated without notice.
Ratings & Reviews
16 reviews
Mullard CV4004 / 12AX7 | new production 12ax7 nos killers
by t smith
I have tried about 15 different tubes and wasted my money on many 12AX7 tubes, and these Mullard CV4004 are the best ones. They have strong mids and an extra-wide soundstage that feels live, as if you're at a concert. omg, the air it added was amazing. They perform exceptionally well, even better than the new stock Telefunken ECC83 TK, which are already good but can't compare to these. The other Mullard tube is almost as impressive. The Genalex 759 is not in the same league as these, and the JJ 803s might be on par with the Mullard CV4004; I have the gold pin JJ 803s coming. Some people claim that the JJ 803s can compete with new old stock (NOS), but I believe the new production Mullard CV4004 is a true NOS killer. the Mullard 12AX7 CV4004 new production tube made a bigger difference in my sound quality than the Western Electric 300B tubes I bought for 1500.00. i got a feeling those JJ-ECC803s gold pins version i got coming will be just as good as the Mullard CV4004. now, go save your money an thank me.
Mullard CV4004 / 12AX7 | Excellent in a Marshall Origin 20
by Bx -
Got a set of three matched and balanced MU-CV4004-12AX7 to replace the stock tubes in a Marshall Origin 20H. Prior, struggled to find settings that weren't harsh. Now, even very trebled out settings sound sweet, clean or distorted. Full and smooth. Delighted with these.
Mullard CV4004 / 12AX7 | KILLER Preamp Tubes
by Gregg
I've used these MU-CV4004-12AX7 in the Preamp section of my Ashdown ABM500 in the past and recently bought 2 to use in my Fender TBP-1 Bass Preamp. The Fender had the original Sovtek 12AX7's in it and these really brought the unit to life. They are clear, warm and punchy and virtually noiseless! Well worth ever penny!
MU-CV4004-12AX7 | Great sounding tube, great price
by Charles
I got two of these MU-CV4004-12AX7 for v1 and v2 of a Marshall DSL 40 combo. It came with JJ’s which work fine and sound pretty good. This tube is a little warmer and sweeter sounding. Definitely helped bring a little more vintage sound to the amp. I used to chase nos tubes but new production seem to be coming around. So save your money, and by from the ruskies. I will be curious to see how long they last. People knock on JJ’s, but they last forever.
Mullard CV4004 / 12AX7 | Good tube
by Steve
They look or sound nothing like a Mullard box plate which I think there inspired from. The Mullard CV4004 are my favourite new production 12ax7. I had good results with them not as harsh as the Tungsol and a well balanced smooth sounding preamp tube for guitar amps. Good reliability and better more realistic price point for new production.