Hi
I have had an SSE for nearly ten years, and it is my favourite amp. I have had trouble with arcing 3 times now, and I am now a little hesitant about dropping a new set of power tubes in.
The first time, when i switched from triode mode to UL when the amp was on.
The second time after a thunderstorm, it also fried the inrush current limiter.
And now the third time after a little standstill, the power tubes started arcing when I turned on the amp.
I remember doing some measurements when i finished the build back in the days. But I can't seem to find that information anymore.
Any suggestions on how to proceed with my faultfinding
Sincerely
Jesper
I have had an SSE for nearly ten years, and it is my favourite amp. I have had trouble with arcing 3 times now, and I am now a little hesitant about dropping a new set of power tubes in.
The first time, when i switched from triode mode to UL when the amp was on.
The second time after a thunderstorm, it also fried the inrush current limiter.
And now the third time after a little standstill, the power tubes started arcing when I turned on the amp.
I remember doing some measurements when i finished the build back in the days. But I can't seem to find that information anymore.
Any suggestions on how to proceed with my faultfinding
Sincerely
Jesper
Arcing is a term used for all sorts of stuff. Here I'm assuming that you are seeing sparks flying inside one of the larger tubes.
I have never seen sparks fly in the output tubes (6L6GC, EL34 or KT88) unless they were severely abused or poorly constructed, and in this case they sparked out when powered up the first time.
Sparking inside the rectifier tube is not uncommon. The SSE runs it's rectifier tube pretty hard. About 10 years ago all three of the major tube makers shipped tubes of less than stellar quality such that many sparked out on first power up in any demanding application, like guitar amps, Dynaco ST70's and the SSE.
To compensate for this a change was made to the SSE board. A pair of diodes and another inrush limiter was added to make life easier on the 5AR4. These parts were TR-1, D3 and D4. These solved the sparking rectifier issue. Your nearly ten year old board may or may not have these mods. Look for three small parts between the 5AR4 socket and the solid state diodes.
The original board was labeled in the silkscreen "Simple SE" with a copyright date of 2006.
Litigation by a company selling a similarly named audio product that was neither Simple, or SE, and didn't even use tubes forced me to change the name of the board to SSE. It seemed that Googling for their product brought up dozens of hits from builders showing off their new SSE's.
All boards labeled "Tubelab SSE" with a 2006 - 2012 copyright date on the top, and "Tubelab SSE 04-18-2012" in metal on the bottom near the rectifier tube have these mods.
If you have the old board you can add these parts off board fairly easily. The diodes are the most important part of the mod.
Add a 1N4007 or UF4007 in series with each red wire from the power transformer. This can be done by removing a wire from the T1-RED connector, soldering a diode to the end of the wire with the band (cathode) on the board end. The diode leads can be cut short. cover this with heat shrink tubing leaving only enough diode wire uncovered to go back into the connector where the wire was taken from. Repeat on the other red wire. These parts do not get hot.
An inrush current limiter type CL140 can be added to the transformer CT wire (red-yel). The CL140 does get pretty warm so heat shrink can not be used. It will need to be mounted somewhere so that it can not touch anything. It goes on the end of the red-yellow wire and the other end of the CL140 goes to the T1-RED-YEL connector on the board. all other wires on this connector should remain as they were.
More info about these changes can be found here:
SimpleSE: C1 value
I have never seen sparks fly in the output tubes (6L6GC, EL34 or KT88) unless they were severely abused or poorly constructed, and in this case they sparked out when powered up the first time.
Sparking inside the rectifier tube is not uncommon. The SSE runs it's rectifier tube pretty hard. About 10 years ago all three of the major tube makers shipped tubes of less than stellar quality such that many sparked out on first power up in any demanding application, like guitar amps, Dynaco ST70's and the SSE.
To compensate for this a change was made to the SSE board. A pair of diodes and another inrush limiter was added to make life easier on the 5AR4. These parts were TR-1, D3 and D4. These solved the sparking rectifier issue. Your nearly ten year old board may or may not have these mods. Look for three small parts between the 5AR4 socket and the solid state diodes.
The original board was labeled in the silkscreen "Simple SE" with a copyright date of 2006.
Litigation by a company selling a similarly named audio product that was neither Simple, or SE, and didn't even use tubes forced me to change the name of the board to SSE. It seemed that Googling for their product brought up dozens of hits from builders showing off their new SSE's.
All boards labeled "Tubelab SSE" with a 2006 - 2012 copyright date on the top, and "Tubelab SSE 04-18-2012" in metal on the bottom near the rectifier tube have these mods.
If you have the old board you can add these parts off board fairly easily. The diodes are the most important part of the mod.
Add a 1N4007 or UF4007 in series with each red wire from the power transformer. This can be done by removing a wire from the T1-RED connector, soldering a diode to the end of the wire with the band (cathode) on the board end. The diode leads can be cut short. cover this with heat shrink tubing leaving only enough diode wire uncovered to go back into the connector where the wire was taken from. Repeat on the other red wire. These parts do not get hot.
An inrush current limiter type CL140 can be added to the transformer CT wire (red-yel). The CL140 does get pretty warm so heat shrink can not be used. It will need to be mounted somewhere so that it can not touch anything. It goes on the end of the red-yellow wire and the other end of the CL140 goes to the T1-RED-YEL connector on the board. all other wires on this connector should remain as they were.
More info about these changes can be found here:
SimpleSE: C1 value
Yes that is exactly what I meant by arcing. Sparks inside the tubes. I must admit, I have only used cheap JJ, EH and TAD tubes so far, so maybe that is my main problem.
The next I am going to try is the electroharmonics 6CA7EH, when I have the courage to fire up the amp again.
But I will do the mod to protect the rectifier tube, you suggest, before anything else. Hopefully that fixes my problem.
Thanks for all the answers so far.
The next I am going to try is the electroharmonics 6CA7EH, when I have the courage to fire up the amp again.
But I will do the mod to protect the rectifier tube, you suggest, before anything else. Hopefully that fixes my problem.
Thanks for all the answers so far.