Good preamp tube options for PI Slot

mwalluk

New member
Right now I'm rolling with a Sovtek in the PI slot of my VHT Deliverance. I wanna try switching it out with something else. What's a reliable brand that works esp well with the PI slot? Tungsol? EHX?
 
Re: Good preamp tube options for PI Slot

there's no such thing as perfect tube for PI. Every amp is different and based on how you like the way it currently sounds you may decide which tube you want. If you feel it's too bright go with JJ, it will warm it up a tad. If it's dark, go with chinese or russian tubes or their re-labeled brands (GT, fender, marshall, mesa...)
If you want more gain you may want to get some hi-gain tube, like JJ ecc803 (or something like that) or use 12ay7 to tame it if it's too loud.

as far as reliability, I've had bad experience with chinese. Rebranded may be better if they do some sort of selection. JJ are also lower noise and IMO more reliable...although noise isn't that big of a concern for PI.

some insist on having a balanced tube, but I wouldn't worry about it. Modern amps use loads of asymmetric clipping anyways, so why bother making the output perfectly balanced when you'll have your preamp make it completely asymmetrical anyways. Also, having it unbalanced adds some sweetness that may be a good thing for guitar. Hi-fi is another story.

this reminds me of questions like "which magnet is perfect for pickups"...it all depends on how the rest of the contraption fits it :)
 
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Re: Good preamp tube options for PI Slot

I Like the EH 12AX7 and the Sovtek LPS has always been a good tube there.
 
Re: Good preamp tube options for PI Slot

If you want more gain you may want to get some hi-gain tube, like JJ ecc803 (or something like that) or use 12ay7 to tame it if it's too loud.

as far as reliability, I've had bad experience with chinese. Rebranded may be better if they do some sort of selection. JJ are also lower noise and IMO more reliable...although noise isn't that big of a concern for PI.

Not to nitpick, but the JJ 803 is actually lower gain than the typical ECC83 by 10% or so. It has a little more "sting" in the highs, so it might just be perception of more gain.

In any case, that is one of my favorite PI tubes. I dont know why, but things sound much clearer with the JJ ECC803. Other than that, the LPS and Mullard RI are my other go-to PI tubes. I kinda prefer the way the long-plates work in the PI hole personally. I have an old RCA 12AX7 that is also the balls as a PI. I keep that one in V1 though.

As for the Chinese tubes and reliability, the Penta brand Chinese 12AX7s are really nice. Ive had problems with Ruby Chinese tubes though.

The Tung-Sol is also really nice. It might not be enough of a difference to most people's ears, but I think it'sa little fatter and clearer. Only downfall is most of my Tung-Sols have developed a 'popping' noise at idle.
 
Re: Good preamp tube options for PI Slot

Not to nitpick, but the JJ 803 is actually lower gain than the typical ECC83 by 10% or so. It has a little more "sting" in the highs, so it might just be perception of more gain.

stand corrected, you're right.
 
Re: Good preamp tube options for PI Slot

Before you you use any New Sensor tube in the PI, shoot them an email with your amp type. Many of their tubes will not take the cat voltage of a follower or phase inverter.
Best
 
Re: Good preamp tube options for PI Slot

Before you you use any New Sensor tube in the PI, shoot them an email with your amp type. Many of their tubes will not take the cat voltage of a follower or phase inverter.
Best

I've been using a Sovtek in the PI for awhile now which works fine, was just looking to experiment a lil.
 
Re: Good preamp tube options for PI Slot

I've been using a Sovtek in the PI for awhile now which works fine, was just looking to experiment a lil.

From what Ive heard, most problems with Sovtek tubes were using a long plate tube in the cathode follower spot.
 
Re: Good preamp tube options for PI Slot

cathode follower circuit pushes the tube more than any other position. One of the reasons is that it overloads max cathode/heater voltage. Lifting heaters for 50-100V above ground helps (and reduces heater hum), but none (or almost none) of the mass produced amps have that implemented...there are few other ways to make CF tube suffer less, but they usually aren't implemented either.
 
Re: Good preamp tube options for PI Slot

are you asking me? if so, I'm all for JJ, regardless of the position, those are my favorite tubes. I've used them in clean amps (fender clone), dirty amps (trainwreck clone) and very dirty amps (soldano and mesa clone) with excellent results. Warm and full tone, but not muddy and noticeably less noise than chinese tubes. I usually play through headphones so I mind noise and do everything to keep my devices noise free :)
 
Re: Good preamp tube options for PI Slot

Bancika - I'm partial to JJs as well, just wondering how the hold up in the PI. Also note it's the short plate one, with those people either love em or hate em.

Edge - I plan on picking up some of the long platted ones.
 
Re: Good preamp tube options for PI Slot

Bancika - I'm partial to JJs as well, just wondering how the hold up in the PI. Also note it's the short plate one, with those people either love em or hate em.

Edge - I plan on picking up some of the long platted ones.

Some of the dudes that HATE the ECC83s LOVE the high gain ECC83s. Even though it's the same type of tube, there's a noticable difference. The regular 83s is nice and warm, and the high gainers are all of that, with some sparkle and bite added in. I dont know why or how it works, but the magic dust they throw on them can be worth it in a spot or two in the amp.
 
Re: Good preamp tube options for PI Slot

Remember guys that the P.I. tube is more a tube of function/gain and not tone....Basically we want a strong,reliable tube in that spot..
 
Re: Good preamp tube options for PI Slot

Bancika - I'm partial to JJs as well, just wondering how the hold up in the PI. Also note it's the short plate one, with those people either love em or hate em.

yeah, I use those short plate everywhere :)
 
Re: Good preamp tube options for PI Slot

Bancika - I'm partial to JJs as well, just wondering how the hold up in the PI. Also note it's the short plate one, with those people either love em or hate em.

Seriously? Wow. I couldn't get them out of any amp I've owned quickly enough. The long-plate ECC803S is a different story, and I have a couple of them for backup, but I have zero use for the plain-Jane ECC83S.

Edge - I plan on picking up some of the long platted ones.

Now you just have me confused. The short plate are the ECC83S, right? And you said you're partial to JJs after the previous post had only mentioned ECC83S, didn't you? So I got the impression you're partial to those. What we have here is failure to communicate.
 
Re: Good preamp tube options for PI Slot

Remember guys that the P.I. tube is more a tube of function/gain and not tone....Basically we want a strong,reliable tube in that spot..

But if we can benefit from some tonal improvements along with some rugged-tough reliability, why not go for it? Can we not have our cake and eat it too? :D Dont deny a fat kid of cake!
 
Re: Good preamp tube options for PI Slot

yeah, I use those short plate everywhere :)

I think every amp Ive owned had a JJ or two. I usually put one in V2 behind a TungSol or EHX. They add warmth and clarity after the TS/EHX feeds in the bite and grind. My Splawn and MKIII sounded phenomenal With a mix of TS/JJs.
 
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