Guitar Gear Forum

I am a long time musician (ive been playing clarinet and sax 20 years) but I am new to guitar. I have a guitar that I've been playing a few weeks now and have been using guitar pedals on my woodwinds (clarinet, sax, flute, harmonica, ext.) For 5 years now; but I just got a tube guitar amp a month and a half ago. It is a centaur s280r keyboard amp. It died on me yesterday. I was playing guitar for about 45 minutes when it sudenly cut out. I thought it was the cable and turned it off and swapped out the cable. I guess it was off for a few seconds so it started working sort of but was super crunchy, had less volume, and would ghost notes. I then grabbed another cable and tried again, it died again 3 minutes later the same way but didnt come back this time. Now it makes a high pitched squeal and make very very little sound with everything cranked. I think it's the tubes. But I cant get to them. The tubes run perpendicular to the back panel and are not easily accessible. I will include a pic. Can someone help me get to the tubes so i can change them? Do I take the back plate off by unscrewing the flat head screws? Do I unscrew the protective caps and take off the bottom receivers for the tubes and change them that way. Or do I have to remove the screws in the Rolex and tear up the tolex to get to the tubes? Or is the problem I'm describing likely not the tubes at all? Sorry if this is a dumb question.
Thanx,
-Matt

I could be wrong, but I'm pretty sure those aren't tubes.

If they are, that's highly unusual for a keyboard amp

It's an old amp. They are tubes. Hammonds are keyboards and have tons of tubes(this isn't a Hammond, it's a centaur. The brand that made the klon centaur pedals. The klon pedal was supposed to actually give the special sauce from their guitar amp into a portable pedal form.) It also has a guitar and bass setting. I got it so it would be a Swiss army knife of sort. Jazz guitar players, bass players, and harmonica players use keyboard amps often. This one even has string reverb. It's a nice little jazz amp (well it was until it died).

These definitely were not made by the same company that made the Klon Centaur. The Klon Centaur was built by an individual guy out of his apartment in Boston. "Centaur Systems" is based out of southern California.

There isn't much out there on this amp, but I'm not certain that it has tubes in it. If it did, it would be ventilated to keep the tubes from overheating. I found a website for them though if you want to try reaching out to them directly

http://centauramp.com/index.html

Thanx for the info. I already found the website and sent them an email before.

heartycorn wrote:They are tubes.

I'm curious to know how you came to this conclusion?

They look like TO-3 transistors (with blue insulator caps/covers), which would make a lot more sense

looks like a Solid state Heat sink on that , those fins , So my guess is it comes out from the other side . Those screws around the face plate should free it up but it probably comes out of the speaker hole or from the front some how . I don't think that is a tube amp but maybe , we'll see.

Have you tried talking to them? Tell them how what they do is affecting you. If that doesn't work, stage an intervention with family and close friends. If they are not willing to change for you, you should consider making life-changing decisions for your own health and well-being. I have tips on how to date tubes, if and when you come to that point.

wut lol

These are definitely TO-3 transistors, not tubes. But also, I doubt they're the cause of the issue. The symptoms you are describing sound like bad filter caps to me. Which btw, is the most dangerous part of an amp if you're not experienced with servicing them. I'd take the amp to a tech or consider buying a new one.