Questions about the V1 tube...

[ElectricTurkey4369]

I heard this is the most important slot, because it is the input stage? What would change if you were to put a better quality 12AX7 in V1, compared to a cheap one?
Im just curious because alot of people seem to like a Tung Sol in their V1 position.

 

[swbo101]

The V1 sets the stage/color/tone of the guitar before the gain stage. Depending on the characteristics of that tube, it gets carried throughout the amp into the power stage. I use a Tung-Sol RI and have been very happy. It articulates the sound and gives it depth, at least to my ears.

 

[crane]

V1 is for sure an important tube : it's the first input tube. The most important thing is that if you have a middle/bad/cheap tube, all the next stages are affected (it's like a river and a hoverdam, right ?).
For example I find JJ ECC83S lacking harmonic, steril sounding. If I put such a tube in V1 I feel I loose a lot all over the amp. But putting that tube in a gain stage, cathode follower, I find it more insignificant.
Get it ?
But another very important tube is the PI, usually the last one (V5 or V6). If affect the tone globally, but without really shaping it. Put a bright tube at this place, all your amp will become brighter. Put a great NOS Mullard ECC81 (CV4024, no advertising ^^) and it will take off a little bit gain, put improve clarity.
The best way is really to try all this. buy/borrow some tube and try them in every position (stay in the 12AX7/ECC83 or 12AT7/ECC81 familly). Your ears are the jury !

 

[94Tremoverb]

The only things I would add to that is to make sure V1 *is* in fact the first gain stage - sometimes it isn't (eg Express, V2 is) and sometimes only for the clean channel (eg Maverick), and in a very few (eg Blue Angel) V2 is more important even though V1 is actually the first stage.

Also, do NOT try a 12AT7 in any cathode-follower position - V3 and V4 in Rectifiers, but also V1 in the Maverick and Blue Angel! - they have too low a cathode voltage rating and will probably fail. Best to keep them for the Phase Inverter, generally. 12AY7s have the same voltage rating issue but do sound very nice as V1s in amps that will take them.

 

[konstantine RK]

whew good thing I did put a Mesa 12ATS7 in V4 or V5!

I like SPAX-7's in V1 V3

I have a Penta Lab chinese in V2. Not a lot of SPAX7 users in this forum...

 

[dodger916]

whew good thing I did put a Mesa 12ATS7 in V4 or V5!

I like SPAX-7's in V1 V3

I have a Penta Lab chinese in V2. Not a lot of SPAX7 users in this forum...

I had one in V1 of my Mark IV until today when I replaced it with a copper grid post Sylvania. I think this one will be staying for a while.

 

[crane]

The only things I would add to that is to make sure V1 *is* in fact the first gain stage - sometimes it isn't (eg Express, V2 is) and sometimes only for the clean channel (eg Maverick), and in a very few (eg Blue Angel) V2 is more important even though V1 is actually the first stage.

Also, do NOT try a 12AT7 in any cathode-follower position - V3 and V4 in Rectifiers, but also V1 in the Maverick and Blue Angel! - they have too low a cathode voltage rating and will probably fail. Best to keep them for the Phase Inverter, generally. 12AY7s have the same voltage rating issue but do sound very nice as V1s in amps that will take them.

Yep, totally right about 12AT7 and cathode follower !
The Triaxis also has V2 or V1 as first gain stage, depending on the selected mode.