1972 Solarus head

[Martin]

I recieved this Solarus head awhile back. The pots date it at 1972.
 I'm trying to find the schematic and service manual with voltages. All of the schematics I've found have a tube rectifier. there is a solid state rectifier on this amp. I'd like to find an accurate schematic for this year amp.
 Here are the problems:
 1. very low output      2. amp hums alot.   3. 6AN8 tube filament not glowing
even though there is 6v to the filament pin on a new tube.
Any thoughts?  Any help/suggestions?

[mike]

Check Aspen Pitman's "Tube Amp Book" for some Sunn schematics; regardless of the model name(Solarus, Sceptre, 100s, 190L, etc.)as long as it's a 60 watt head with two 6550 power tubes and rev/trem, they're all essentially the same.  You might be able to goose a little more wattage out of the amps that have a solid state rectifier(as opposed to the ones with tubes).  My amp tech(I'm on the west coast) is Don Butler, who is a well-respected British tube amp specialist, but he's not unfamiliar with tube Sunn's(especially after all the stuff I've sent his way!)....check out his site (www.tone-man.com); if you're not adverse to shipping the amp to him, perhaps he could help you, but you'd want to email him first explaining the problems. Good luck!

[David Fralix]

reply: I think the reason for no heater light up, could be tube filament is out, or
         tube socket is dirty. Make sure voltage is getting to tube.
                                                               
                                                                         David

[wil]

for a schematic for your Solarus go to http://www.sunnamplifiers.com/schematics/solarus.gif

[mike]

Every schematic for a Solarus head that I see shows EL-34 power tubes and a GZ-34 Rectifier Tube. I have a 1971 Head, with 6550's and no rectifier tube, must be SS rectification. Does anyone know where I can get a schematic for this one? I have the Tube Amp Book by Aspen Pitman, and the schematic shows the same EL-34's and GZ-34 Rectifier tube. What gives?

[Don T.]

Hello:
 I'm pretty sure the circuits are the same except for the fullwave diode rectifier.
Don T.