doublechaz
New Member
Finally measured those tubes. I hope I did it right. There was a CD player connected to aux and playing for audible checks, but during the testing the unit was switched to phono which had nothing connected. No audio, no hum, no crackle. Neg of the DMM was connected to chasis, Pos to the pin in question.
v14
pin 1 351 V
pin 2 -22.3 V
pin 3 32.5 mV
pin 4 0 V or 3.3 V AC
pin 5 0 V or 3.4 V AC
pin 6 -22.2 V
pin 7 350 V
pin 8 0 V or 365 mV AC
pin 9 377 V
v15
1 350 V
2 -22.1 V
3 67.6 mV
4 3.3 V AC
5 3.4 V AC
6 -22.1 V
7 350 V
8 1.3 V AC
9 377 V
V16
1 351 V
2 -22.3 V
3 90.2 mV
4 3.3 V AC
5 3.3 V AC
6 -22.4 V
7 351 V
8 1.7 V AC
9 378 V
V17 (didn't really glow today as viewed through the socket like it normally would)
1 351 V
2 -22.3 V
3 as high as 34 mV but sometimes sagging to 0
never seen it do this before. Don't know if it was the socket
or what. Did I make a cold solder joint or a short putting in the
10 ohm?
4 3.25 V AC
5 3.37 V AC
6 -22.4 V
7 351 V
8 312 mV AC
9 378 V
You can see the accuracy error in my DMM from the slightly different voltages on direct connected pins, but it should be good enough to sound any alarms.
After the tests with the unit right side up again I took each tube's temp from above straight down so the tube crown filled the view port of the IR gun and got v14 172.7 F, v15 182.6 F, v16 172.7 F, v17 150.8 F.
I did notice while under there that there is a factory looking resistor connected between 2 pins on v17 that doesn't exist on the other three tubes. Pictures available if needed.
The Bach organ and violin stuff I'm playing sounds pretty good at volume similar to being in the front of the original performance. I haven't really tested much for very low or very high volume.
Extra credit question: Anyone familiar with the Decca 1961/1993 Arthur Grumiaux 2 CD set of Bach Complete Sonatas and Partitas for Solo Violin, and if so does anyone know what is that terrible background rumble throughout the recording? Was that venue built directly below the Autobahn or something? It sounds like a diesel ship 10 miles away. I suppose it must be the HVAC, perhaps resonating off a tympany left exposed instead of being covered.
v14
pin 1 351 V
pin 2 -22.3 V
pin 3 32.5 mV
pin 4 0 V or 3.3 V AC
pin 5 0 V or 3.4 V AC
pin 6 -22.2 V
pin 7 350 V
pin 8 0 V or 365 mV AC
pin 9 377 V
v15
1 350 V
2 -22.1 V
3 67.6 mV
4 3.3 V AC
5 3.4 V AC
6 -22.1 V
7 350 V
8 1.3 V AC
9 377 V
V16
1 351 V
2 -22.3 V
3 90.2 mV
4 3.3 V AC
5 3.3 V AC
6 -22.4 V
7 351 V
8 1.7 V AC
9 378 V
V17 (didn't really glow today as viewed through the socket like it normally would)
1 351 V
2 -22.3 V
3 as high as 34 mV but sometimes sagging to 0
never seen it do this before. Don't know if it was the socket
or what. Did I make a cold solder joint or a short putting in the
10 ohm?
4 3.25 V AC
5 3.37 V AC
6 -22.4 V
7 351 V
8 312 mV AC
9 378 V
You can see the accuracy error in my DMM from the slightly different voltages on direct connected pins, but it should be good enough to sound any alarms.
After the tests with the unit right side up again I took each tube's temp from above straight down so the tube crown filled the view port of the IR gun and got v14 172.7 F, v15 182.6 F, v16 172.7 F, v17 150.8 F.
I did notice while under there that there is a factory looking resistor connected between 2 pins on v17 that doesn't exist on the other three tubes. Pictures available if needed.
The Bach organ and violin stuff I'm playing sounds pretty good at volume similar to being in the front of the original performance. I haven't really tested much for very low or very high volume.
Extra credit question: Anyone familiar with the Decca 1961/1993 Arthur Grumiaux 2 CD set of Bach Complete Sonatas and Partitas for Solo Violin, and if so does anyone know what is that terrible background rumble throughout the recording? Was that venue built directly below the Autobahn or something? It sounds like a diesel ship 10 miles away. I suppose it must be the HVAC, perhaps resonating off a tympany left exposed instead of being covered.