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Hi all, new to the Trinity world - was planning to build one but found a well assembled V6 second hand. It does sound a bit "off" to me though - I would describe it as being strident and has a pronounced quack in the lower midrange when used at humane volumes. This trait seems to follow it between the 2 cabs I have available (2x12 with TT's and 1x15 BBQ) and an appalling assortment of guitars. The demos I hear of these amps seem quite a bit smoother so I decided to start by checking the guts. Workmanship is quite good and clean and all I could find different from the schematic I have found online is R15 is 470ohm instead of 820. All voltages seem reasonable except for V3 which shows

1. 184
2. 39
3. 82
6. 184
7. 37.3
8. 81.7

Mains 119VAC, B+ with tubes 340V

Swapping in another tube changes the numbers a bit but pin 3 still reads higher than the voltage chart. All other voltages in the amp are lower so that is why it stands out to me. Should I be switching in an 820ohm for R15? Would that effect the tone much typically? Cheers!

Measure the resistance values on the PI and confirm they are correct before you change anything, and confirm the wiring is correct and triodes not mixed up etc.

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Thanks for the reply. Everything seems to be correctly connected and resistors are correct. R12 reads a bit high at 62k (I am assuming that is acceptable?) but otherwise all within reason.

I did not receive the build schematic used in construction with the amp so the R15 of 470 may be as intended. I guess my real question is, what value for R15 should be in place as the baseline in a V6 and what effect would there be on altering that value?

470R is more gain than 820R in that position and lower resistances on PI tail deliver more drive than stock 56K.
Neither should make much change to your voltages.
Next, I would try swapping tubes around. That can make changes to your voltages as well as tone.

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Hi to all and I am new as well.........I don't mean to highjack someones thread but I have similar voltages or different voltages than listed on the schematic. Let me first say to Stephen thanks for the help with the resistors.

My voltages are:

V1:
1-165
3-.8
6-135
8-1.0
V2
1-130
3-.89
6-269
8-130.6
V3
1-219
2-52.8
3-74
6-209
7-50.7
8-74
V4
3- 12.5
7- 344
9-328
V5
3-12.5
7-330
9- 321
V6
3- 346

are these voltages anywhere near right ???