Just completed Crack Build,but have a few questions

robertone1

New member
Hi,just finished my Crack build on the weekend and in the process of burning in the tubes etc,so I can get onto installing the SpeedBall after some time.
This is one sweat sounding amp right of the bat on my Sen's HD650's.If this is how it sounds like now,can't wait to install Speedball and try some tube rolling.
First question I have is regarding voltages on a couple of terminals(mains voltage is 240V). Terminal 9 and B6 are a bit higher than the 10-15% rule.
Amp sounds great so far(also have M'Caps EVO on output).
Other question is how hot should this amp get?
Took some temp readings around amp and in some places its quite hot.Im thinking I should of painted the case plate in high temp paint,I can still smell the metal paint
I used venting off.
Resistance checks were right on the money.

12AU7 tube          131 F
6080 base of tube 125 F
6080 top of tube  203 F
Power trans top    116 F
Case top front        107 F
3K ohm Resistors  one 154 F the other 100 F (why the difference in temp from one to the other?)
220uf 250V connected to 14U  136 F
220uf 250V connected to 13U    112 F
220uf 250V connected to 20u    89 F
5W resistor                                  132 F             


Terminal  Voltage    Actual
1                75-90    90 
2                170        169
3                0            0
4                170        168
5                75-90    101
6                0            0
7                100        112
8                0            0
9                100        119  (slightly higher than the 10-15%) rule
10              0            0
11              0            0
12              0            0
13              170        166
14              0              0   
15              185          191
20              0              0
21              206          214

A1            90            100
A2            0                0
A4            0                0
A5            0                0
A6            90              88
A7            0                0
A9            0                0

B1            90              88
B2            170            169
B3            100            112
B4            90              100
B5            170            168
B6            100            119    (slighty higher again than 10-15%)
B7              0              0
B8              0              0

Will post some pics when I get around to paint the woodbase.
Thanks.
 
One triode of the 12AU7 is running a little bit high voltage on the plate, but it is nothing to worry about. Temps are fine.
 
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