Preamp Tubes? - Who, What, When, Where, Why, and How?

[MartyStrat54]

I have been going through the back pages of the thread and I was looking for something in particular. Made it to page 16 and still a no go. It was a conversation I had with Josh about a thread I started asking about the signal path of a DSL/TSL. I posted a link to the thread on my reply post to Josh. I have tried all sorts of ways to find it and nothing works. I guess I will try and go through another 10 pages or so. Man, I forgot about some of the arguments that took place. Good one's too!

 

[RiverRatt]

It's Karma, man. That's what happens for that "needle in a haystack" comment a few pages ago.

 

[wegman]

I wish I was smarter on this stuff so I could contribute more.

Question gentleman.

How important is the PI tube? I was running a GE there and I wasn't like the dynamics. I swapped it out for black plate and all of the sudden the dynamics changed and things got more articulate. I didn't think the PI had that much bearing on playability of amp but it does mine.

Anyone else experience this?

 

[RiverRatt]

I wish I was smarter on this stuff so I could contribute more.

Don't worry about it. It'll come to you. I'm just a dumbass who reads a lot.

Question gentleman.

How important is the PI tube? I was running a GE there and I wasn't like the dynamics. I swapped it out for black plate and all of the sudden the dynamics changed and things got more articulate. I didn't think the PI had that much bearing on playability of amp but it does mine.

Anyone else experience this?

There were pages about this further back in the thread. Changing the PI tube can completely change the character of the amp. I used to always use a Raytheon 12AT7 short black plate for a PI. Now I prefer a high-gain 12AX7. Tastes change. I think I liked the 12AT7 back before I got some good glass in the preamp & power amp because it took away some of the harsh upper mids and treble. That's not an issue anymore, so now I like to open the amp up and let it breathe.

 

[wegman]

There were pages about this further back in the thread. Changing the PI tube can completely change the character of the amp. I used to always use a Raytheon 12AT7 short black plate for a PI. Now I prefer a high-gain 12AX7. Tastes change. I think I liked the 12AT7 back before I got some good glass in the preamp & power amp because it took away some of the harsh upper mids and treble. That's not an issue anymore, so now I like to open the amp up and let it breathe.

Thanks for info RiverRatt.

This thread is monster. I have gone back and read some parts but it is just over whelming.

Yes changing my PI tube totally changed the character of the amp, for the better.

As I was rolling tubes tonight I noticed that the orange letter RCA's I have are different. One has long plates and another short plates. I just noticed this. The long plates sound way better then short plates. Is there some magical difference between long plates and short plates?

 

[solarburn]

Thanks for info RiverRatt.

This thread is monster. I have gone back and read some parts but it is just over whelming.

Yes changing my PI tube totally changed the character of the amp, for the better.

As I was rolling tubes tonight I noticed that the orange letter RCA's I have are different. One has long plates and another short plates. I just noticed this. The long plates sound way better then short plates. Is there some magical difference between long plates and short plates?

The short plates are less microphonic then the long plates. As far as one sounding better that is up to your ears.

 

[racko7566]

Ok guys, I just got my first mullards and I'm pretty exited. My line up as of now consists of 9 NOS tubes. First 4 from Marty, an Amperex 7025, a black plate Raytheon 12ax7, and 2 sylvania 12ax7 grey plates. I like all of the above but I happen to love the blackplate that seems dead when I look at it hot when rollin, but its far from dead in sound. After Marty hooking me up with my first NOS tubes I went to Ebay to try my first auction. I bid on and won 2 old RCA tubes.
One was a 1952 RCA BLACK PLATE JRC 12AX7 and the other was an RCA 12AX7A 12AX7. Both are good sounding tubes. Now my new additions to the lack of oxegen club are 2 mullards and a SUPER STRONG SYLVANIA 12AX7 thats way hot. The one mullard is a 1966 coded 163 B6B1 mullard 12ax7 tube with the short gray plates and the O getter. I do remember in the best thread of all times, Marty saying after 66 they were using old junk equipment so I stay away from post 66. Well Im of on a rollin session, Any suggestions for new combos for me? ps. sorry for the super run on sentence.

 

[MartyStrat54]

Damn, you're getting some smoking tubes there. Those JRC's are some of the very best older RCA's. And a 1952? Geez, they'd only been making 12AX7's for five years. That's a baby. Make sure you post a picture of that one. I'd love to see it. Also, a lot of people feel that a 12AX7A tube is as quiet as a 7025. I think there is some truth to that. I think a 12AX7A is a much better tube versus a regular 12AX7. It's not a night and day difference, but there's something there that makes it better.

 

[MartyStrat54]

It's Karma, man. That's what happens for that "needle in a haystack" comment a few pages ago.

Well I found it pretty fast, so if you ever need a needle found, call me.

 

[racko7566]

Damn, you're getting some smoking tubes there. Those JRC's are some of the very best older RCA's. And a 1952? Geez, they'd only been making 12AX7's for five years. That's a baby. Make sure you post a picture of that one. I'd love to see it. Also, a lot of people feel that a 12AX7A tube is as quiet as a 7025. I think there is some truth to that. I think a 12AX7A is a much better tube versus a regular 12AX7. It's not a night and day difference, but there's something there that makes it better.

Heres the 52 slant getter RCA Marty.

Its a great tube, but I havent found its mate like I have with the Raytheon.

 

[MartyStrat54]

Wow, great picture. So it has a slant getter? Is it a black plate as well? Looks like it measured pretty high. Speaking of that...

 

[RiverRatt]

The wires coming off those filaments look scary. I'd be afraid to swap that one out while hot.

Racko, If I'm using RCAs, I like to use one in both V1 and V2. They seem to sound better that way to me. Of course, low gain in V1 and high gain in V2.

 

[racko7566]

Wow, great picture. So it has a slant getter? Is it a black plate as well? Looks like it measured pretty high. Speaking of that...

Yes, yes, and yeaaaa!!!

 

[Procter2812]

Well...

I got the Telefunken Long plate and to be honest it sounded real good but was noisy. Background hiss. I paid 18 quid for that sweet piece and it was noisy!

So im gonna ask the seller for a refund... not good.

 

[ken361]

Well...

I got the Telefunken Long plate and to be honest it sounded real good but was noisy. Background hiss. I paid 18 quid for that sweet piece and it was noisy!

So im gonna ask the seller for a refund... not good.

try in the v2?

 

[MartyStrat54]

Probably be best to get a refund, because if it has a problem, it will just get worse. If the seller offers a return, go for it and find yourself a good Telefunken. You'll be happier in the long run.

I just sent a bunch to Solar (Joe) and he went nuts over those damn Tele's.

 

[racko7566]

The wires coming off those filaments look scary. I'd be afraid to swap that one out while hot.

Racko, If I'm using RCAs, I like to use one in both V1 and V2. They seem to sound better that way to me. Of course, low gain in V1 and high gain in V2.

Hey RiverRatt, I'm gonna try my Rcas together tonight in v1 and v2 Ill let you know how they sound.

 

[MartyStrat54]

I can't wait to hear the low down tonight from Mr. Sunshine. He rolled a bunch of Tele's and he will be telling us the dope on them later this evening.

 

[ken361]

dropped the mullard ,v1, v2 tele, v3 sylvania long plate,v4 stock,v5 stock. its pretty smooth! least for today lol!

 

[racko7566]

Just noticed the tops of my 2 new mullards are pinched like the amperex I got, but the mullards are pinched two ways. Is this on all mullards or just certain years? As I speak ( cyberneticly) Im getting ready to try the mullard with an amperex in v1 and the mully in v2. Be right back