Tube Amps 101: ?

[T.M.A.]

Ok guys,

I've been trying to educate myself about all this online and am getting quite overwhelmed...

I'm in the middle of swapping pre tubes in my JCM 800 2204 and am running into all kinds of jargon like "Cathode Follower Position" (V2?) and "Phase Inverter Position" (V1?) among others. Supposedly certain tubes are better for these positions than others, based mostly the size of their plates. Voltages???

Will someone take a second to brake this down for me???

THANKS

Also, if someone would like to make some recommendations on tube configurations to try out, that would be much appreciated and COOL!

Here's what I've got

4 JJ EC83s
2 Electroharmonix
1 Tungsol
1 Bugera
3 Groove Tubes
2 Sovtek LPS
1 Sovtek WP
1 Shuguang "Preferred Series" (from the tube store)

All 12 Ax7's of course...

PEACE!

[SirJackdeFuzz]

Re: Tube Amps 101: ?

Can not ad much to be honset.

What i can tell you is this :

My fav affordable valves (toobs) is the JJ brand.
Not that i have tested all the others, but what i have read, what i have been told, and what i have in my amp.

If you can afford it, NOS is the way to go (New Old Stock)
But according to EuroTubes, they are expensive . . . i mean, real expensive.

http://www.eurotubes.com/eurotubes-tube-comparison-JJ-Electronic.htm

Hope this helps !

[Chickenwings]

Re: Tube Amps 101: ?

i like EH 12ax7s in marshalls cos of the low noise, high gain and midrange bark.
Power tubes?...whatever is fresh and biased properly but generally i lean towards jjs because they are reliable and have the most headroom/low end.
V1 will make the biggest difference in tone shaping and the last preamp tube is the Phase inverter which will have the most effect on "feel".
In the end tho...you have plenty of toobs....experiment and go with what your ears tell you. have fun!

[T.M.A.]

Re: Tube Amps 101: ?

Hey guys,

Thanks for the feedback. It's really not as complicated as i thought. I found a few articles that broke it down nicely for me the other day. I've been experimenting and have found JJ ECC83s to be the best you're probably going to be able to get. i can imagine something better in my mind, but I don't know if it exists in reality. A good pickup with some JJ's and you should be set. The sovtek LPS are dope as well. I think i like their low notes more. The preferred series tube from the tube store has very nice lows. It really tightened everything up. I'll probably either end up with JJ or LPS in V1. Gonna order some JJ 803's to see how those fare...

CHEERS and GOOD LUCK...

[misterwhizzy]

Re: Tube Amps 101: ?

I guess one thing to note is that there are only a few tube factories left in the world. One in the Slovak Republic produces JJs, the Reflektor factory in Russia produces quite a few brands, including Sovtek, Mullard, Electroharmonix, and Tung-Sol, and the Chinese factory produces Shuguang (and Sino?). Groove Tubes, Ruby, and others take these tubes, test them, then rebrand them based on how well they tested.

Sometimes you may find it worthwhile to have someone beyond your dealer check these out, but usually, I just go to Doug's Tubes and describe what I want. He may charge a couple extra bucks for high gain, but usually it's less than the overhead of Groove Tubes.

Once you get beyond that, you will probably notice differing model numbers, most of which start with 12AX7. It's the X that needs to stay the same for similar amounts of gain. The WA, WB, etc. that you typically see after that base model designation doesn't mean much to me, but it's a good way to tell which are the higher-end tubes. For example, Sovtek puts out a WA, WB, and LPS. Of these, I think the LPS is by far the strongest model. For JJs, they designate tubes as ECC83, which is a European designation for what we Yanks call the 12AX7. All this is kind of irrelevant, except for the fact that all the different model numbers used to confuse me.

As far as what you're talking about, I think that in a JCM800, the V1 position takes the input signal and boosts it way beyond what is coming in. It does this in two stages, because each tube has two amplifiers inside (dual triode). V2 has another gain stage and a cathode follower to drive the tone stack, and V3 is the phase inverter. In the end, V1 sets most of your tone, and V3 sets most of the feel, and in Marshall-style amps, it has a big effect on the power-tube distortion, because a lot of what you hear is actually the PI distorting.

Bottom line is you have a lot of room to play, and your ears will tell you better than any stupid theoretical discussion I may be posting online. For what it's worth, in an amp with similar heritage, I've found the best complement to be Tung-Sol in V1, Ruby 12AX7AC5 HG+ in V2, and JJ long-plate (ECC803S) in the PI position, although many players like the Sovtek 12AX7 LPS in that position. Good luck.

[T.M.A.]

Re: Tube Amps 101: ?

I guess one thing to note is that there are only a few tube factories left in the world. One in the Slovak Republic produces JJs, the Reflektor factory in Russia produces quite a few brands, including Sovtek, Mullard, Electroharmonix, and Tung-Sol, and the Chinese factory produces Shuguang (and Sino?). Groove Tubes, Ruby, and others take these tubes, test them, then rebrand them based on how well they tested.

Sometimes you may find it worthwhile to have someone beyond your dealer check these out, but usually, I just go to Doug's Tubes and describe what I want. He may charge a couple extra bucks for high gain, but usually it's less than the overhead of Groove Tubes.

Once you get beyond that, you will probably notice differing model numbers, most of which start with 12AX7. It's the X that needs to stay the same for similar amounts of gain. The WA, WB, etc. that you typically see after that base model designation doesn't mean much to me, but it's a good way to tell which are the higher-end tubes. For example, Sovtek puts out a WA, WB, and LPS. Of these, I think the LPS is by far the strongest model. For JJs, they designate tubes as ECC83, which is a European designation for what we Yanks call the 12AX7. All this is kind of irrelevant, except for the fact that all the different model numbers used to confuse me.

As far as what you're talking about, I think that in a JCM800, the V1 position takes the input signal and boosts it way beyond what is coming in. It does this in two stages, because each tube has two amplifiers inside (dual triode). V2 has another gain stage and a cathode follower to drive the tone stack, and V3 is the phase inverter. In the end, V1 sets most of your tone, and V3 sets most of the feel, and in Marshall-style amps, it has a big effect on the power-tube distortion, because a lot of what you hear is actually the PI distorting.

Bottom line is you have a lot of room to play, and your ears will tell you better than any stupid theoretical discussion I may be posting online. For what it's worth, in an amp with similar heritage, I've found the best complement to be Tung-Sol in V1, Ruby 12AX7AC5 HG+ in V2, and JJ long-plate (ECC803S) in the PI position, although many players like the Sovtek 12AX7 LPS in that position. Good luck.

Super Stellar information there Mr. Whizzy! I'm definitly sending a LIKE your way! Thanks!

[Grenade]

Re: Tube Amps 101: ?

Go do a search at the Marshall Forum. Some good guts over there also.

[Gone_Shootin]

Re: Tube Amps 101: ?

Try Tung-Sol 12AX7s in the gain stages, and a JJ in the phase inverter. That's become my go to combo.