Sunn Solarus lots of hum

[kupervaser]

I bought a Sunn Solarus amplifier from ebay.
The seller said it was all original and he also sent me the tubes. The tubes are 6550. However the transformers do not look that big to me.
Can you check the pictures and give me some ideas on what tubes should be there?

Here are the pictures:








And another thing. I am in Europe. What is the best way to handle, convert this heat to 240 volts with a built in step down transformer, or get a portable transformer?
Is the convertion with a built in transformer difficult? Are there any partsto be changed or just adding a transformer?

Thanx

[mckinnon audio]

   Hi there,I think it's an older one,look on the front under the name to see where the amp is made.If it says Portland Oregon,it's the older version,should have a pair of EL 34's,(6CA7's) for outputs.Check the phase inverter tube,older models have a 7199,newer ones have a 6AN8 (A).The older ones have the 16 and 8 ohm stickers on the back,where the newer ones had 8 and 4 ohm stickers.As far as the AC goes,I would get an external AC step down transformer rather than try to mount one in the amp itself.Good luck,Mel.

[EdBass]

I think so too, those definitely look like the 40 watt trannies.

[Oli]

Hi,

I live in Germany (with 230V/50Hz ) and use the step down transformators as well, no problem.

Sorry with the tubes, I`ve Sorados and 2000S, they all take the 6550/KT 88.

Greetings

Oli

 

[kupervaser]

Thanx,

It is made in Oregon:



Just asked the seller again and he told me KT88 are the right tubes. He got them out of the amp and stored in it.

[loudthud]

Ask the seller where the reverb tank is.

[mckinnon audio]

  Hi there,the mains fuse is 2 amps,I believe on the KT88/6550 model it is a 4 amp circuit breaker,plus like Ed says,the tranny's are too small,I really think it's a 40 watt model that has the wrong output tubes in it,Mel.

[kupervaser]

do el34 en kt88 have the same pinout than? thanx

[Isaac]

  Hi there,the mains fuse is 2 amps,I believe on the KT88/6550 model it is a 4 amp circuit breaker,plus like Ed says,the tranny's are too small,I really think it's a 40 watt model that has the wrong output tubes in it,Mel.

All of my 6550 models have a 3 amp slo-blo fuse. I agree that the transformers look too small.

[EdBass]

do el34 en kt88 have the same pinout than? thanx

Not really the same, pin 1 is the suppressor grid in the EL34, but in your amp you can plug in a KT88; the pinout isn't the issue IMO.
I think the issue is the current draw requirements for a KT88, 100ma more for the heater, more plate current, etc. vs. an EL34 taxing that little power transformer, the one everyone keeps mentioning as being "too small".
The entire power supply would be working a lot harder, and it's already working it's little butt off with EL34's installed. I doubt (but don't know for sure) if you could even get the bias close enough to spec with a pair of KT88's installed.
Here's another indicator as to it being a less than good idea; those fuses that also keep getting mentioned, why do you imagine that they are only 2 amp while the KT88/6550 amps require a 3-4 amp fuse?

Also, why you would want to use the KT88's? You know you wouldn't get more power using KT88's in that amp, right?

I'm not trying to be obnoxious, I'm just curious as to why you would want to. If I'm missing something I'd like to know... 

[kupervaser]

It is not that I really want to use the KT88 tubes. It is that the seller sold me this amplifier in none working condition and he included a pair of KT88 tubes as original tubes. Already twice he assured me that those are the tubes which has been used in this amplifier before it broke down. I am just trying to find out which tubes I need to use when I will start repairing (or at least search for a problem) this amplifier. I really don;t care which tubes to use as long as the amp starts working. I like the sound of EL34. ALl the amps I own have EL34 in them.

Thanx

[EdBass]

It is not that I really want to use the KT88 tubes. It is that the seller sold me this amplifier in none working condition and he included a pair of KT88 tubes as original tubes. Already twice he assured me that those are the tubes which has been used in this amplifier before it broke down. I am just trying to find out which tubes I need to use when I will start repairing (or at least search for a problem) this amplifier. I really don;t care which tubes to use as long as the amp starts working. I like the sound of EL34. ALl the amps I own have EL34 in them.

Thanx

I think the seller was "confused", however if you got a pair of KT88's that are period correct for that amp as part of the deal, and they are healthy, I'd say you probably did OK.
What is the amp doing/not doing?

[kupervaser]

I am not sure yet. I haven't plugged it in yet. I need a step down transformer first.

This was the description:

SUNN SOLARUS TUBE AMP
 1968 vintage tube sound!
This amp worked great for years.
Sounded amazing!
1 day it just would not turn on.
I never got into it to look.
It has been sitting for a couple years now. Stored in a climate controlled room.
This is a good chance to get a great deal.
Could be a simple fix. I have no idea. I am tired of it just sitting.
These are not easy to come by.
If I did not have too many amps as it is, I would get this running again!
The tubes were yanked out and stored. I could use the tubes in other amps, but if the amp breaks 300, I will include them.

THIS IS SOLD AS IS!



I got it for $435 which is nog bad if you are in Europe.

[woody2762]

As you look at the back of the amp, the far left tube should be GZ-34 and the two in the right-center-front should be an EL34 pair.