5150 mkI head preamp tube layout

[hellraiser85]

What is the correct layout?

1: POWERAMP TUBES <--- V4 V3 V5 V2 V1

or...

2: POWERAMP TUBES <--- V5 V4 V3 V2 V1

I was thinking that "layout 1" was the correct one, but a technician of my town retubes my 5150 as "layout 2". In addition, he fitted the bias to 15 mA (with 4 JJ 6L6GC tubes). Is it correct this?

Thanks!

 

[LSD-Studio]

bias 15mA is WAY to cold.

the layout is printed on the PCB

 

[Loren Littlejohn]

Yeah holly fuck 15mA? Even double that is still a tad cold.

 

[hellraiser85]

Thanks! It's POWERAMP TUBES <--- V4 V3 V5 V2 V1, but what is the phase inverter? V4 or V5?

 

[53Crëw]

The phase inverter is V4. (Assuming V4 V3 V5 V2 V1, which is how the 5150 schematic is drawn.)

Many people seem to think in terms of V5 V4 V3 V2 V1 and call V5 the phase inverter - - same tube, though.

My 5150 came stock running 18mA per tube. I believe most came from the factory running 12-15 mA.