Solarus head and maybe bottom

[Bruce Mission Amps]

Hey guys,
Going through a friends garage yesterday I ran into an old Sunn Solarus head (with tubes) and an empty Sunn 2x12 bottom with no speakers or back panel.
I own it now...it needs work but it's not really a beater.
I'll shoot some photos of it later this weekend.
Anyhow, I'd be tempted to restore this head and cab if it's worth it... and if the vinyl can be found so I can whip up a new back panel.
Any suggestions?

Bruce

[HRobert]

Get it fixed.  It'll be worth the time and effort.  Some good 12" speaker would really make the amp sound great.  I'm a fan of the JBL K series, but some good Celestions or Emenence would sound great also.  Try to get speakers with a high SPL rating.

Rob

[pickinatit]

I put a Celestion Vintage 30 & a G12H30 in my Solarus 2x12 cab and they sound great together.

[Ryan Phelps]

Bruce,
Definitely get that head running (will probably need new filter caps, 3-prong A.C. cord and maybe new output tubes) and buy some new speakers! For vinyl, the best match available is from Steve at Angela Instruments (www.angela.com); I think this is Fender-era Sunn vinyl. Send Steve an e-mail....I don't think he has it listed on his website. It comes in two different cut sizes, so check the size of the new back panel. I've also use black Vox vinyl for a replacement back panel on my Sunn 1 x 15 cab. You have to get up real close to see the difference in the vinyl texture.
Also, the Solarus 2 x 12 cab was an "open-back" cabinet with two short back panels top and bottom. I own a mint Solarus with the matching Solarus 2x 12 cab and this is the back panel configuration. Each panel measures 8" tall. Carefully inspect the vertical cleats for the back panel screw holes. Unless it was modified in the past, you should only find screw holes near the top and bottom of the vertical cleats, not in the middle portion.

Good luck!
Ryan

[Bruce Mission Amps]

Well, the 2x12 cabinet has too many screw holes in the rear panel hook strips to have two small panels so I 'm thinking either it was modified or it had a closed back at one time.

I haven't had much time to do anything other then slide the chassis out of the head cab.
It is all original on the inside (no repairs and no mods) but someone stole the darn knobs off it!
It looks like all the E-caps and pots are dated around the middle to late 1971 and it does not have a rectifier tube but solid state diodes in the power supply instead.
The power cord was cut off the chassis for some reason.. (I hope it wasn't done by a tech who found a blown power tranny or something like that)... it has a pair of old GE 6550s in now but no preamp tubes in it.
Maybe one of the PA tubes is shorted and a the owner snipped off the power cord, etc.

Even though I doubt it is, the transformers look big for a 50 watter, more like the size used in amps claiming to be 75 watts to as much as 100 watts in some cases.

I'm really quite interested and curious to see if I can make it it something without investing too much $$.
I'm already behind the 8 ball by a whopping $50.00....
I can't locate a schematic for this amp that does not have a rectifier tube... is it the same otherwise?

 

[Isaac]

The transformers look right to me, for the 60 watt versions with 2x6550 power tubes. Diode rectification would raise that to about 80 watts, IIRC. Not much of a difference, but no power sag when playing loud.

Check the tubes. You may have already turned a profit, if those are proper old 6550's.

[loudthud]

Bruce,

The closest schematic is probably the 190L. You can find a copy in this thread:

http://sunnforum.ampage.org/sdp/index.php/topic,4772.0.html

I noticed from your pics that you amp has the later 190L/350L vibrato PCB. What exactly is printed on the tremolo bug? Ever seen a part like that? When that part goes bad, no signal gets through the amp. A replacement or work-a-round needs to be devised.

[Bruce Mission Amps]

The ink on the device says:
SIGMA Datacell 301R2-12

Yes, I saw on a different, tube rectifier Solarus schem where, (except the reverb input signal), it looks likes the dry signal path is in series with the resistance of the cell.
I hope it is not bad. If it is bad I'd have to think hard about keeping this module.
It looks like proper Cd cells for good sounding vibratos are hard to find... well, Cd cells with the right on-off resistances and skew/ramping rates.

A bit off topic:

I still build all my own Fender Vibrato bugs.
At one time had a few hundred of these good Cd cells and Ne bulbs and was selling them to other dealers, repair shops, etc., ... at first, it took me a little while to find those Cd cells with good on-off resistances and a decent skew/ramping rate.

I was the one who "designed" (designed: stealing the Fender bug device idea) and provided the data for the Weber vibrato bugs.
But, suddenly and for no explicable reason,  all those good Cd cells became unavailable.
I don't know if I just lucked into a few hundred in a supply house or what, but when reordering them one day, I was told they were all gone and there won't be a replacement.
Anyhow, Weber had to get them from someone else (in China I suspect) and ended up using different Cd cells and with different rates from what I've been told.
I have no personal experience with the newer Weber vibrato cells and don't know how well they work.