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

[MartyStrat54]

Quick question...should pre amp tubes always be covered with the RF shield? I notice some amps cover them, while others don't. Any pros or cons?

The better amps cover all of the preamp tubes, will the general rule is to cover V1. V1 is the tube most susceptible to RF interference, such a short-wave (HAM) radios and CB's (Citizen Band).

A well made amp can work without a cover on V1, but it is a good idea to have one.

 

[LPMarshall hack]

The better amps cover all of the preamp tubes, will the general rule is to cover V1. V1 is the tube most susceptible to RF interference, such a short-wave (HAM) radios and CB's (Citizen Band).

A well made amp can work without a cover on V1, but it is a good idea to have one.

I assume you can buy them? There is a JMP for sale locally that I wanna get, but there are no RF shields on them.

 

[MartyStrat54]

I assume you can buy them? There is a JMP for sale locally that I wanna get, but there are no RF shields on them.

If you get the amp take a moment to look at the socket. Some of the older amps use different type sockets. A popular older style that is still in use is a high shoulder base that accepts a twist on style can (shield). All the different type shields can be obtained from:

Antique Electronic Supply

 

[LPMarshall hack]

If you get the amp take a moment to look at the socket. Some of the older amps use different type sockets. A popular older style that is still in use is a high shoulder base that accepts a twist on style can (shield). All the different type shields can be obtained from:

Antique Electronic Supply

Thanks...

 

[Landshark]

If all the preamp tubes look the same and say Tung-Sol on them, that's what they are. Do they all have short plates? The Tung-Sol is actually one of the better CP preamp tubes. The Ruby EL34BSTR is made by Shuguang in China. Joe likes these tubes in his DSL50.

Yeah, I figured that amp would be wired more old school. It looks like a really nice head for the price. Just curious, where is it actually made?

Yea they are all short plates... I was thinking I had seen on here a time or two that they were decent preamp tubes. I actually though about leaving them in V3 and V4 when I get some more cash rounded up and put a couple good ones in V1 and V2. I'm also thinking about louading the remaining Tung Sols in V3 and V4 of the TSL when I get the money for some beasty NOS tubes for its V1 and V2. Those JJs are starting to get on my nerves with how much darker they are... When I get my cash ready I think a good mullard in V1 will be my best bet for the Vox. She can be a little too pretty at times, although I really love how pretty that clean channel is.

I believe it said 'Made in China'... which is kinda a bummer that such a nice amp wasn't made in good old England, but that explains the buy it new price of $599.99. I probably wont ever part with it though.

 

[Landshark]

The better amps cover all of the preamp tubes, will the general rule is to cover V1. V1 is the tube most susceptible to RF interference, such a short-wave (HAM) radios and CB's (Citizen Band).

A well made amp can work without a cover on V1, but it is a good idea to have one.

HAHA! the Vox doesn't have a cover shield on V1.

 

[ken361]

miss out on a rca last night went for 9 bucks! and a tungsol for a 11, I think

 

[RiverRatt]

Time for today's episode of "What the hell is it?"

I thought I knew what these two tubes were at a glance:

Then on the back there's this:

"Japan Westinghouse" with smooth plates.

 

[MartyStrat54]

That's leaving us hanging. Where did you see them? On PEEBay? I like the marketing philosophy with those tubes. 12AX7 in massive font. On the other side is the ink color that makes RATT ??? question my sanity is: Made In Japan. Although I will say it is in a lot larger font size than most. Some are like this on a tube. Made in Japan...asshole.

So yeah, I would like to know where you saw them. I'm assuming they are Matsushita's. Wouldn't you like to get some NEC's to try out?

 

[MartyStrat54]

Mister Ratt-Your 1967 Russian military, 5000+ hour EL84 has been mailed to you. You should receive it shortly. It is yours to keep. When it shows up, make sure the wife knows it's a freebie and tell her, "See...not all of the tubes cost money."

 

[RiverRatt]

I should have you on hand for those other hard-to-explain moments. Thanks much!

I bought those tubes off eBay today. BIN $15. Anything that weird, I have to own it. I'm thinking they are Ei tubes. AFAIK Matsushita never made anything with a smooth plate, but it would be nice if they are Matsushita. Ultra-rare, only 3 ever made, and I'll have 2 of them. I'll keep them for a year or two and sell them for $110 (like the guy on eBay right now with the two Matsushitas for $110).

 

[Landshark]

Well I went to H&R BLock today and now have a preloaded card with some sweet cash on it!:Ohno: Time for some pre amp tubes! I'd like to buy the recommended V1 and V2 tubes for my TSL and Vox. I'm ready to make it sound GOOD!

 

[core]

Well I got the Raytheon Grey Plates and the Telefunken in today. Added in with the RCA 7025 in the 6100 it is definitely an improvement! Seems a lot smoother. Tell me, they don't glow near as bright as the OG Marshall pre amp tubes is this normal for these?

As soon as I can get the static and crackle issue solved this will be a killer amp. I will upload pics once I can take some.

 

[guitarmartin416]

So...just for shits and giggles, I took an old 1964 Sears amp I had layin around. I loaded it with all Telefunken pre tubes.........wow, just wow!



now if only it were 30watts louder!!!!!!!

 

[CKCinMass]

How do the Brimar Preamp valves rank with you folks?

I found 3 of them in my Old Sound City 50 Plus (I'm doubtful that they will be in it when I sell it - they'll probably wind up in my 2204).

 

[RiverRatt]

Hey, I found a YouTube video on audiotubes.com with some good tube porn (I want a Mazda!). It has some very interesting Telefunkens in it. Watch when he starts talking about "Selected" Telefunken smooth plates, especially the one with the blue tip. You can see that it's a smooth plate, has the diamond in the bottom, and has seams on the top. Telefunken is listed in the factory codes in the Philips Factory Code book, but I've never seen a Telefunken that had the characteristic Philips pinched top seams until this video.

[ame="http://www.youtube.com/watch?v=_6d-cZB7DgA"]http://www.youtube.com/watch?v=_6d-cZB7DgA[/ame]

 

[MartyStrat54]

So...just for shits and giggles, I took an old 1964 Sears amp I had layin around. I loaded it with all Telefunken pre tubes.........wow, just wow!



now if only it were 30watts louder!!!!!!!

Hook it up to a 412 cab with four Man 'O Wars and it will sound 30 watts louder.

 

[MartyStrat54]

I think most of the Tele's that I sold Joe were the "Select" versions. I guess that's why he bought so many. Some still had the paper on them. Another select tube had a yellow tip on it. You will find this on Telefunken's and other Philips tubes.

 

[guitarmartin416]

Hook it up to a 412 cab with four Man 'O Wars and it will sound 30 watts louder.

good point....maybe I'll try that!

 

[RiverRatt]

I think most of the Tele's that I sold Joe were the "Select" versions. I guess that's why he bought so many. Some still had the paper on them. Another select tube had a yellow tip on it. You will find this on Telefunken's and other Philips tubes.

Did any of yours have a pinched top? I've never seen that on a Tele before.