v1 ,info

[mkstylee]

Is it a pretty much given fact that v1 is nearest to the input jack on most amps??,And then the PI is the furthest away??
many thanks

[mkstylee]

Anyone??

[DBI5]

I've never really thought about it to be honest with you.

Has something specific occurred for you to ask this question?

[mkstylee]

Not really mate nothing bad.
I just have quite a few amps and when replacing pre valves i would like to be sure the v1 and so on to the PI go in the right order,as my sets usually include a balanced for the PI and so i can choose a nice one for v1

[Herbvis]

With marshalls that should be a safe bet

[John 14:6]

The first gain stage V1 tube is under the metal can. The can is there to help reduce noise in the first gain stage.

[GuitarBuilder]

DANGER, DANGER, WILL ROBINSON!

Don't assume anything like this when it comes to schematics. You should find the specific schematic for your amp and verify which is V1, etc.

For example, V1 in a JVM410 is an EL34 Power Tube!

[John 14:6]

DANGER, DANGER, WILL ROBINSON!

Don't assume anything like this when it comes to schematics. You should find the specific schematic for your amp and verify which is V1, etc.

For example, V1 in a JVM410 is an EL34 Power Tube!

Here are the JVM preamp tube roles as detailed on the JVM Forum. I had a JVM205H and as far as I know V6 and V7 are the power tubes. The original poster has a YJM100 like mine and V1 is the first gain stage under the can.
I get your point and agreee that no one should believe something just because the read it on the internet.

V1 (under the metal can), V2 gain stages, V1A, V2B are used in all modes, the rest is switched in/out depending on the mode.
V3A: tone control buffer.
V3B: channel mixer/ parallel loop send
V4A: FX mix
V4B: Reverb Mix
V5: Phase splitter.

[Dave W]

I could be wrong and probably am, but I would double check V1 being a power tube. That would be very odd.

Is there a Marshall amp where V1 is not the farthest preamp tube away from the power tubes and the phase inverter is not the closest one?

[Dave W]

Well, just went over to the handy dandy new Marshall amplifier schemantics section, much thanks to Surf and all the contributing members, and shure as shit, V1 in the JVM410 is the first Power tube. That surprised me. I would have has a hard time mashing a ECC83 in a EL34 socket ha!

So, would it be safe then to always assume with Marshall amps that putting aside V-codes, that its a safe bet to assume that the input tube(first preamp tube) is always furthest away and the phase inveter tube(last preamp tube) is closest to the power section?