Seeking 12AX7 preamp tube, seller recommendations

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JMPGuitars
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Re: Seeking 12AX7 preamp tube, seller recommendations

Post by JMPGuitars »

colossal wrote:
Sun 05/10/20 8:08 am
JMPGuitars wrote:
Fri 05/08/20 7:32 pm
On the other hand, I don't recommend anybody EVER use JJ EL84s. They're trash.
I have found the glass envelope on the JJs to be VERY thin. Way too thin. They become quite brittle with routine use. Not recommended.
They're also dangerous. They have the flashing issue on so many of them it's cuckoo. https://www.youtube.com/watch?v=21G6TkukwY8

I keep seeing this recurring from other people that make the mistake of buying them. The flash can be nothing, or a sign it wants to explode. In either case, it's a great example of poor quality.
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Re: Seeking 12AX7 preamp tube, seller recommendations

Post by Bieworm »

I know you don't want to hear it, but I never had any kind of trouble with sovteks. The sound is debateable but they are very sturdy. The EL84M are very robust. I know..because the reverb driver in my Vibroking is an EL84..of I use regulars they die quickly..
In my 6L6 amps the power tubes are always tungsol new production. Those 5881 and 7581 are awesome
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Re: Seeking 12AX7 preamp tube, seller recommendations

Post by zaphod_phil »

I agree, they're OK and generally solid. Just nothing exciting tone-wise :)
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Re: Seeking 12AX7 preamp tube, seller recommendations

Post by ZeroPointEnergy »

I will update my findings after the tubes come in, for my JCM 800. They "could" be here by late tomorrow, but I figure it might easily be a day or so late, because of the pandemic, IDK. But this time I paid extra for faster delivery service.

They are all 12Ax7's. One is Tung-Sol ECC803s, the other Tung-Sol just says 12ax7. A Mullard Mu12ax7, and a Genalex gold lion ECC83/12AX7.

I'm wondering if I should have ordered a mullard CV4004, instead of one of the tung-sols.

It's disappointing to have "most" of my amp back, but it's missing the "singing sustain". Little from my amp made me smile more deeply, than when the amp goes into singing sustain mode.

Here's hoping for the best when the tubes arrive.
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Re: Seeking 12AX7 preamp tube, seller recommendations

Post by crgfrench »

I've had great results with the new production Mullard CV4004.
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Re: Seeking 12AX7 preamp tube, seller recommendations

Post by JMPGuitars »

crgfrench wrote:
Tue 05/12/20 10:24 am
I've had great results with the new production Mullard CV4004.
How would you characterize them compared to the normal new production Mullard 12AX7s?
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Re: Seeking 12AX7 preamp tube, seller recommendations

Post by crgfrench »

The only other 12AX7s I have used are the JJECC83S, never tried the Mullard 12ax7s. I cant tell much of a sonic difference but the Mullard 4004s are definitely heavier duty physical construction and the glass is thicker than the JJs. Both have lasted a few years now just fine, but I'm just playing at home now and then.
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Re: Seeking 12AX7 preamp tube, seller recommendations

Post by ZeroPointEnergy »

I am happier than before, but I'm not happy that I still don't have singing sustain back yet. Seems like I need higher gain preamp tubes.

I like the Mullard's the best, they are the most musically dynamic and I like how the gain structure sounds. The genalex is similar to the mullard but not as nice in the gain structure, but has decent touch sensitivity.

The Tung-Sol's are good, the gain is better, but not as musically dynamic as the Mullards.

So, next up will be an order of high gain mullard versions of CV4004 and the MU12AX7. I'm done after that! I need some power attenuation so I can get the power tube overdrive involved a bit more.
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Re: Seeking 12AX7 preamp tube, seller recommendations

Post by ZeroPointEnergy »

JMPGuitars wrote:
Tue 05/12/20 10:38 am
crgfrench wrote:
Tue 05/12/20 10:24 am
I've had great results with the new production Mullard CV4004.
How would you characterize them compared to the normal new production Mullard 12AX7s?
I did not get enough at the same gain, so I can't tell yet much of a difference. I think I like the CV4004 better for fuller sound and note blooming, but the MU12AX7 seemed quite similar. I need to get more of these tubes, just normal gain, to make a more accurate side by side comparison.

Most of mine were also low noise low microphonics, and I feel that changed the sonic character somewhat. So I can't really make definitive conclusions yet. I blew up one of my Mullards, which is a bummer.

I will report back probably this summer when I can afford to get more tubes in for taste testing. hehe
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Re: Seeking 12AX7 preamp tube, seller recommendations

Post by JMPGuitars »

ZeroPointEnergy wrote:
Thu 05/28/20 8:17 am
I did not get enough at the same gain, so I can't tell yet much of a difference. I think I like the CV4004 better for fuller sound and note blooming, but the MU12AX7 seemed quite similar. I need to get more of these tubes, just normal gain, to make a more accurate side by side comparison.

Most of mine were also low noise low microphonics, and I feel that changed the sonic character somewhat. So I can't really make definitive conclusions yet. I blew up one of my Mullards, which is a bummer.

I will report back probably this summer when I can afford to get more tubes in for taste testing. hehe
I actually bought a CV4004 Mullard, and compared it to a new Mullard 12AX7. They're both within spec for a 12AX7. However, the CV4004 had a slightly lower amplification factor, and I think also lower plate resistance. I'll retest them and post the results eventually. I have not listened to it yet at all.

Low noise/low microphonics from a tube supplier just means they might have tested the tubes. It could also be lies.
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Re: Seeking 12AX7 preamp tube, seller recommendations

Post by ZeroPointEnergy »

JMPGuitars wrote:
Thu 05/28/20 8:33 am
ZeroPointEnergy wrote:
Thu 05/28/20 8:17 am
...

Most of mine were also low noise low microphonics, and I feel that changed the sonic character somewhat. So I can't really make definitive conclusions yet. I blew up one of my Mullards, which is a bummer.

I will report back probably this summer when I can afford to get more tubes in for taste testing. hehe
...

Low noise/low microphonics from a tube supplier just means they might have tested the tubes. It could also be lies.
I found the low noise and low microphonics mullards to be low gain and I did not like using any of them, too low on the gain, and I ordered 4 preamp tubes, most are Mullards. So that was a big disappointment, but I have reliable backups.

I found high gain Mullards the best in V1, but I need to try more to tell which I like better and what the differences are. If there's another stimulus check coming, then I'm good to go and will report back with more!
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