Mullard CV4004 mini-review

[misterwhizzy]

Just replaced V1 in my JCA50H this afternoon with my new Mullard RI CV4004. It replaced an EHX 12AX7 that sounded good enough, but I really like the smoother mids that I had heard in a now burned-out Mullard ECC83. But man, that thing had a ton of gain--probably because I asked Doug to select it that way.

Anyway, all good news on the tone front. The mids are a bit more forward and less raspy than the EHX (or other new production tubes I've tried), but overall the balance is fairly even. It seems to make the highs sweeter while lowering the noise floor and increasing clarity a touch. I think the bigger change was in the overdrive channel, which I had wanted to be an extension of where the crunch channel taps out.

I played through it with my Les Paul. The crunch channel will clean up very well when switched over to the '59 in the neck and the volume rolled back even with the gain on about 7, then the bridge will thicken it up and add a ton of crunch before we even get to the overdrive channel, which goes easily into Rust In Peace levels of gain with the knob on 4 and enough treble (even set low) to maintain good bite and definition. The bass was noticeably tighter with this tube than with the EHX or the Svetlana I had tried in there beforehand. I also like it better than either new production Tung-Sol I have, and it blows away the short-plate JJs.

All in all, it really sounds like a keeper and a significant tone upgrade. Well worth whatever Tube Depot was selling them for.

[FuseG4]

Re: Mullard CV4004 mini-review

Good to know that it's a decent tube. Old stock prices can be ridiculous but modern tubes often have this midrange thing going on, so it seems like the CV4004 gets a little more of the "open" sound I want? Old stock to me usually feels like clear bass and treble and smooth mids. I thought the sovtek lps was not bad but like others I've had trouble with microphonics in combos. So often I go EH cuz they have the treble I like and I would sacrifice a little bass to have that clear sound when clean and almost a little grainy when driven. Cuz you can dial back treble but it's hard to add what isn't there if you start with darker tubes like JJ. The Tung sol I have a hard time hearing the difference from EH so I usually just go eh.
so it seems like this is similar enough to eh/tungsol but has a nicer sound.
I appreciate you sharing your findings cuz I had been wondering if they're worth the price.


Sent from my SM-G930U using Tapatalk

[BenPerkins]

Re: Mullard CV4004 mini-review

It’s an excellent tube. It’s taken the fizz out of my OR15 and also helped the Soak channel on my Carvin Belair 212. The Soak channel previously sounded terrible - now it sounds great, especially with single coils.

[Rex_Rocker]

Re: Mullard CV4004 mini-review

I really like the CV4004 in my Krank Rev Jr. I feel this is the tube to try to thicken up/smooth out a bright amp. I think it achieves this a lot better than the JJ ECC83S which is what most people use because it doesn't lose as much detail, and it has a deeper, chunkier bottom-end.

[FuseG4]

Re: Mullard CV4004 mini-review

I will have to try one at some point
I got a Westinghouse in v1 of my main amp but the rest of mine are a mix of sovtek, Chinese, and JJ. They all sound ok but nothing special. The JJ I don't like in v1 but they are rugged and low noise at least. The Chinese ones sound the best but have occasional pops and ticks

Sent from my SM-G930U using Tapatalk

[misterwhizzy]

Re: Mullard CV4004 mini-review

It’s interesting that to my ears, a good Chinese tube sounds thick and strong, which are adjectives I’d normally associate with a Russian.

[misterwhizzy]

Re: Mullard CV4004 mini-review

Old stock prices can be ridiculous but modern tubes often have this midrange thing going on, so it seems like the CV4004 gets a little more of the "open" sound I want? Old stock to me usually feels like clear bass and treble and smooth mids.

That's probably better-phrased than what I wrote. That sounds like what I hear.

I thought the sovtek lps was not bad but like others I've had trouble with microphonics in combos. So often I go EH cuz they have the treble I like and I would sacrifice a little bass to have that clear sound when clean and almost a little grainy when driven. The Tung sol I have a hard time hearing the difference from EH so I usually just go eh. so it seems like this is similar enough to eh/tungsol but has a nicer sound.

The LPS has always been a bit boring to me. It's clear, but it just doesn't really have any character. To my ears, the Tung-Sol is a bit brighter than the EHX, and the EHX has a bit more grainy upper-mids. The EHX 12AX7s I've had also sound like they have more gain than most other tubes.

I appreciate you sharing your findings cuz I had been wondering if they're worth the price.

That's why I wrote it. Thanks for giving an in-depth response.

[Wattage]

Re: Mullard CV4004 mini-review

Hmm didn't care for them in anything I tried them with. I found them very stiff in my Dual Terror and my EVH III 50


I've got 2 new ones if anyone is interested