Amp problem

sweave

I have a Trace Elliott C30 Speed twin amp and one of the valves in the power amp -  an el84 - has a load of gunge on it and is stuck. I hesitate to apply much force to try to get it out. 
Any advice - is this likely to be an easy fix or is it time to take to a tech?

sweave

I'm trying to post an image from Flickr but it doesn't seem to be working - not sure if that is because I am using an android tablet. Here is the link
https://flic.kr/p/SPX3bh

Maynehead

Try rocking it in a circular motion. Hopefully after a while it will loosen up, and you can continue to rock it whilst pulling slightly until it comes out.

sweave

Thanks - do you think the tube socket has melted? The others look a little scorched.

timmysoft

In a speed twin its almost certainly melted, those amps sounded great but were built incredibly poorly!

ICBM

First try getting it out when it's hot - obviously use a cloth or some kitchen roll so you don't burn your hand.

That's not the socket which has melted, it's some sort of hot glue by the look of it. The valve socket may also have melted though, if it's still got the plastic ones they fitted around this time. Even if it's just some hot glue that's run down into the socket you'll probably have to replace the socket, it's very difficult to clean them well enough to make a reliable electrical contact.

As timmysoft says these amps are extremely poorly built. Just think yourself lucky it isn't a Trident .

sweave

Thanks for the feedback. I'll get it back up to temperature and try removing the valve again (set stuck when cold). Melted glue sounds more likely as the amp was still working when I last switched it on. Suppose the key question is why it melted.

ICBM

sweave said:

Melted glue sounds more likely as the amp was still working when I last switched it on. Suppose the key question is why it melted.

These amps run very hot anyway, but if the valve is on the way out it will be worse. It's also possible someone repaired the amp with the wrong kind of glue at some point...

timmysoft

ICBM said:

First try getting it out when it's hot - obviously use a cloth or some kitchen roll so you don't burn your hand.

That's not the socket which has melted, it's some sort of hot glue by the look of it. The valve socket may also have melted though, if it's still got the plastic ones they fitted around this time. Even if it's just some hot glue that's run down into the socket you'll probably have to replace the socket, it's very difficult to clean them well enough to make a reliable electrical contact.

As timmysoft says these amps are extremely poorly built. Just think yourself lucky it isn't a Trident .

I had the Bonneville 100w head, it was awesome but i wanted the switching options of the Speed Twin, i regretted that fairly quickly! I ended up running a couple of MK1 tramp heads into marshall VS412's, from memory it sounded great, in reality it probably sounded horrible.

ICBM

The Mk1 Tramps were great - soundwise. They were unreliable, partly because the power sections of the amps were under-spec, and partly (in the combos) because they insisted on fitting under-rated speakers… a practice studio I did repair work for bought a job lot of them, and every one of them blew up in short order. After TE fixed them, with similar results, I phoned and asked why they were putting 60W 4-ohm speakers in 65W/4-ohm amps - they said it was because they liked the sound of the speaker being pushed really hard. Doh. After that I just fitted higher-rated 8-ohm speakers and both the amps and the speakers stopped failing.

The Mk2 'Tramp Tube' series weren't quite as bad for reliability but sounded worse… probably one of the only cases where transistors sounded better than valves in basically the same amp design.

This whole era of Trace was really poorly designed and built though, right up to the V8 valve bass amp, which I had one of briefly. Supposedly a high-power professional-quality amp, but couldn't be toured - the chassis was so flimsy that one bounce and the transformers would flex the whole thing and crack solder joints everywhere because the PCB was bolted to it rigidly, as were the PCB-mounted pots (at right angles to the PCB).

"Trace Failalot" as someone here said...

DJH83004

You could try using a hairdryer aimed at the bottom of the valve & base area as it def looks like hot glue, which will melt at hairdryer temperatures. Quite how it got there sounds like a bit of a mystery, other than a bit dripped off the gun during assembly?