Mullard CV4004 / 12AX7 Preamp Vacuum Tube

14 Reviews
SKU: MU-CV4004-12AX7

Availability: Usually ships within 24 hours.

USD $‎27.95
Each
QuantityPrice
1 – 4USD $‎27.95
5 – 99USD $‎26.95
The new Mullard CV4004 / 12AX7 vacuum tube has a short plate construction making it more stable and better able to handle the vibration inside guitar combo amps.

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 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.

Other Mullard tubes12AX7 Types

Additional Information and Downloads

Tube Matching Information:
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Warranty Information and Return Policy

Warranty Period: 3 months

All 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

14 reviews

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Marshall + Mullard = Melodious

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I purchased a matched pair of these along with a matched and balanced quad set of Mullard CV4004/12AX7 tubes for my Marshall JCM602 combo, and after slightly adjusting the bias back to the referenced -42V I am very pleased. The clean channel sounds much better, i.e. the bass response is punchy and tight while the mids are well balanced, and the highs are sharp and crisp. In relation to the stock Svetlana tubes, the overdrive channel does lose just a tad of that trademark Marshall tone to my ears, but overall I consider the tradeoff to be well worth it.

Excellent in Orange Rockerverb MKIII

by

Wow! Absolutely perfect tubes for this amp (clean and both dirty channel positions) and they sound fantastic! I'll be using these from now on. They are exactly the sound I have been looking for - smoother and much more full sounding than Tung-Sol's in these positions, without question.

Nice Valve

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Used this as a replacement for a AVT 275. A whole lot less noise. Made for even nicer clean ranging from tweedy to voxy. A hair less gain on OD1&2= cutting down on the muddy OD 2. Which made for some sweet ZZ-tone with the treble cut out.

Great Tube!

by

I recent did a switch in my 1979 Marshall 2203 JMP amp which was a US model one with 6550s and had it modded to take el34s which I just bought the JJ E34L tubes here as well and I am happy with there sound as well. I play a lot of AC/DC so hence why I switched to El34s. I ordered one Mullard CV4004 12ax7 along with the power tubes to try something new. I currently have the mullard in V1 and it sounds great. I know a lot of sites say this tube is the highest gain 12ax7 you can get right now but that is far from true. This tube is an average gain tube which I think most people want but the thing I loved about it compared to a few others I tried in V1 was the tube is clear and warm with a bit of that fat cream to it. It didn't sound as brittle or harsh compared to a few other GT and JJs I have tried in V1 and it still packs a great punch. I would buy this tube again for sure!

The guy below beat me to it.

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I have 1 of these Mullard CV4004's and I found a use for it in V2 in my Peavey Valveking 2 100 Head. 'Took off some of that low end and really drove into nice distortion. I don't know why, because in V1 it is pretty tame, and that's with swapping V1 and V2 around (use Shuguang/Ruby in V1, even in my Dark Terror, which provides creamy distortion).
I bought a Joyo Mjolnir the other day, and it came with stock Sovtek EL84 and JJs in the preamp slots. Sound wasn't quite what I wanted right out of the box, but I didn't give up on the sob and spent the whole evening swapping around almost every kind of preamp tube (have 10 different or so).
Finally, I found some creamy, nice distortion with the Mullard in V2, just like with my VK. Wasn't quite right, though, so I did what I do with all my amps: I slammed a Ruby in V1. That almost nailed it. Now, the Ruby that I have in V3 in the DT or the JJ and Preferred Series that I use in my VK (it was almost), the Sovtek LPS (not at all, too clear and lost distortion), and everything else, didn't balance it out out while maintaining creamy grain and crunch. Of them all the Tungsol came to the rescue and nailed it. Had not found a use for the Tungsol earlier, but now I'm glad I bought it. Also, the Mullard that I put over in the Mjolnir was replaced by the EH for V2 in the VK, which I now see as a cheaper version of the Mullard CV4004.