BE 100 - Tube Layout and nomenclature please !

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ElMariachi78

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Hello,

I am new to this forum and this is my first post after reading lots of threads about preamp tubes for the BE 100.

I have the 2016 model of the BE 100 with the newly added gain structure switch.
My amp came with these stock tubes:

4 x TAD EL34B-STR Power Tubes
2 x ARS branded JJ/Tesla 12ax7 preamp tubes in V1 and V2
2 x ARS branded Chinese 12ax7a/7025 preamp tubes in V3 and V4

I want to try different tubes especially in V1 and V2.
From reading some threads about preamp tubes in the BE 100 I was getting confused about the order and the function of the tubes ( V1 for BE, V2 for HBE and clean channel?)

My understanding in the past was that the preamp tube farthest away from the power tubes is V1 ( the first tube from left to right when standing behind the amp)
but I read in a thread that V1 is the second tube from left to right... .

I would like to have an official statement on this: Please name the preamp tubes from left to right : is it V1,V2,V3,V4 or is it V2,V1,V3,V4 ?
And in which channel does which tube-position work?

Sorry if this is a dumb question but I need to know this ;-)


Thank You very much in advance !
 
What's important is:
First tube= HBE/clean
Second tube= BE
Third tube= cathode
Fourth tube= PI
(from a post a few years back)
 
OK, thank you for the info!

So I guess the first tube is V2 and the second tube is V1 ?
 
ElMariachi78":3tbanofg said:
OK, thank you for the info!

So I guess the first tube is V2 and the second tube is V1 ?

No, The first tube closest to your input jack is V1.
Then comes V2, V3, etc...

Basically, if you look at your amp directly from the rear, the tube all the way to the left is your V1.
The tube all the way to the right (closest to your power tubes) is your V4 phase inverter.
 
Thanks, this was my understanding too until I read this thread: http://www.rig-talk.com/forum/viewtopic.php?f=57&t=183001

These posts from Mike D. , poster above in my thread, made me believe the BE100 is layed out different:

"My understanding is that v1 is the second preamp tube in line from left to right.
V2 is the first tube.
I agree with rgorke as to their function."

"...in other words, v1 (2nd tube)is for BE.
V2 is for HBE and clean"

In my experience with tube rolling in the BE100 so far I would agree with his statements.
In my world V1 is the first input stage of a preamp so the BE100 is off the norm V1 being the first tube from left to right.
I wonder why there is no diagramm or description in the manual of the BE100 how the preamp tubes are layed out.
 
V1 triode a is the boost (HBE) and also the clean.
V1 triode b is just the clean

Clean channel = V1a > V1b into V4 (phase splitter)
BE Channel = V2a > V2b > V3a > V3b into V4 (phase splitter)
HBE Channel = V1a > V2a > V2b > V3a > V3b into V4 (phase splitter)
 
Dirty Dog":2omuemsa said:
V1 triode a is the boost (HBE) and also the clean.
V1 triode b is just the clean

Clean channel = V1a > V1b into V4 (phase splitter)
BE Channel = V2a > V2b > V3a > V3b into V4 (phase splitter)
HBE Channel = V1a > V2a > V2b > V3a > V3b into V4 (phase splitter)


Cool,thanks! :thumbsup:
 
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