Sunn Solarus lots of hum

[EdBass]

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

Oh yeah, I forgot about that part. I'd check the filter capacitors first, you can do that without needing 115 VAC. Once you get the voltage sorted out, I'd see what the PT is doing.
Good luck with your project!

[pickinatit]

he assured me that those are the tubes which has been used in this amplifier before it broke down. [/quote

I'm no techi  like these other guys,  but it occured to me that
maybe there's a connection between the KT88 tubes being used and the amplifier breaking down ?

[Soundmasterg]

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

Oh yeah, I forgot about that part. I'd check the filter capacitors first, you can do that without needing 115 VAC. Once you get the voltage sorted out, I'd see what the PT is doing.
Good luck with your project!

Ed is right on here. The filter caps (don't forget the bias circuit cap) and rectifier tube and fuse are good places to start. After that, the power transformer should be checked. Do all checks without tubes (except rectifier tube) first before you add tubes. If it blows a fuse with the rectifier tube in, then take it out and try to power on again once the fuse is replaced...if it still blows the fuse, then the PT could be bad, or bad filter caps. Get your voltage supply sorted first and then you can check into it, but realistically, if the filter caps are original, they all need to be replaced at this point.

greg

[kupervaser]

Yeah, I will probably change all the electrolitycs anyway. But thanx guys. But does the KT88 has the same pinout as El34? You can't just swap them right? Basically someone have rewired this amp for KT88 on purpose but didn't think off wrong transformers?

[EdBass]

 

Yeah, I will probably change all the electrolitycs anyway. But thanx guys. But does the KT88 has the same pinout as El34? You can't just swap them right? Basically someone have rewired this amp for KT88 on purpose but didn't think off wrong transformers?

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.

They are not the same, but in your amp KT88’s can be used without rewiring the tube sockets. Pin 1 in a KT88 is connected to the metal tube base, and the beam forming plates; sort of the KT88’s version of the suppresser grid, is internally connected to the cathode. Your Solarus uses pin 1 to connect the suppressor grid to the cathode.

[kupervaser]

Allright thanx a lot. I will start working on this amp as soon as I have my step down transformer. I bought this one:

http://www.tubeampdoctor.com/product_info.php?cPath=27_47&products_id=146

Is that ok?

[EdBass]

I'd say the bigger the better. That one looks pretty beefy to me!

[mckinnon audio]

  Hi there,at a 1000VA rating you'll be able to draw around 8A of current at 115VAC,lots of headroom,you can run 2-3 amplifiers off of that and not worry.Good luck,Mel.

[kupervaser]

Thanx. Yes I need a bigger one to power my Model T as well.

[Oli]

Hi,

I use this one for my Ampeg V4B and Sunn350B (not at the same time):

http://www.yatego.com/multimediastore/p,49ae620e902e2,430dbd8940f3d2_4,spannungswandler-vorschalttrafo-230-110v-300-watt?sid=06Y1300803796Y01f6c250f6da4bcd6f

300 VA is more than enough, I think the 2000S used app. 250W (VA) Peak when I did some measurements with the troubleshooting.

Though I paid app. 50€ for a 500 VA step down transformator at Westfalia, but they are not in stock any more.

Anyway, TAD is a great place - I bought all my tubes there, they repaired my Ampeg and the service is A +++! They really love tube amps !


Greetings

Oli

[kupervaser]

Thanx Oli, I bought 1000VA on ebay for 60 euros. However won;t need that much power.

[Oli]

I jused compared the 200S with the Solarus. Ed hind is really the best way to check it as you ll see the PIN 1 connected/not connected.  You ll find the SUNN Schematics here: http://sunn.ampage.org/site/schematics/

As far as I can tell all the big caps 600V tend to bad - I had the main trouble with theses and with the chokes. 

Good luck with your amp!

Greetings

Oliver

[Isaac]

For the record, VA and watts are not the same thing, though, in this case, they're close enough for the difference not to matter.

[Oli]

Hi, shure , you are right. The idle power of the whole system woundn`t be that high, so I set VA and W equal....(I think it should not be necessary to attach a  star-delta connection.... .... ).

Thanks & Greetings

Oli