DrGonzo
Hey guys,
Having a little jam today and turned my amp on to notice a horrifric squeeling sound. ?
The I plugged straight in no pedals, and the squeal is quite hectic, then it stopped for a while and i could play normally but with a occasional crackle and farty sound on my low notes :'(
Im fully suspecting it to be an issue with the tubes? The amp is a Fender Supersonic 22W, pre and power amp tubes are the stock Groove tubes and about 3 years old.
I will check tomorrow if it is a microphonic preamp tube problem but i think it could be the power amp tubes dying?
Funny thing last week at band practise I noticed a definate change in my amps tone, slight loss of bass end and kind of ice pick sharpness - Now of course this could be psychological as it was the week building up to to a gig of mine, but i clearly remember stopping and telling the other guys that, wait a second, why does my tone sound so shitty!
Any advice? I am probably gonna do a full retune this week, but im just hoping its not something more....
AlanRatcliffe
Yeah, most likely a microphonic valve. Easy enough to check for.
DrGonzo
Thanks Alan, I will check that out today.
Can you tell me where I can obtain some quality tubes in Cape Town area? JJ's would be nice, or any other recommendations you have.
I want to change out the power tubes (6V6) regardless, i think its about time, I have been pushing them very hard for the last few years.
ezietsman
I've got lots of things from these people before
http://www.mrvalve.co.za. Also, tubedepot is good, if you cannot find what you want locally. Some of the stores will sell some of the tubes but expect heavily inflated prices.
AlanRatcliffe
I also use Mr Valve locally, but KCA NOS for most NOS and Tubestore for new production since KCA ran out of SED 6L6s (looks like SED is now defunct).
Last time I asked in a shop, they told me that only the workshop had spare valves and to bring the amp in for a service. My response, was something along the lines of ? - while some amps need biasing if you change the power valves, all amps are user serviceable as far as the pres go and many on the power side too.
DrGonzo
Thanks guys I will check out the tube story and hopefully its that what is causing the problem...
Cheerss ?
DrGonzo
It seems like it is a microphonic pre amp tube.
Quick question Alan (or anyone else in the know) - Do you know if you can get Tungsol tubes locally? or will I have to order from overseas?
ezietsman
DrGonzo wrote:
It seems like it is a microphonic pre amp tube.
Quick question Alan (or anyone else in the know) - Do you know if you can get Tungsol tubes locally? or will I have to order from overseas?
I got my Tung Sol 6V6GTs from Tubedepot. Couldn't find them here then.
AlanRatcliffe
Mr Valve has Tungsol.
DrGonzo
Ok so I replaced the microphonic valve with a brand new tungsol and it solved the problem... Until now.. ☹
The tube in that same position from about 5 mins ago has turned heavily microphonic... some serious squeal and theremin like pitch shift effect when pencil comes near it...
Whats goin on.... gonna take my baby in tomorrow to see whats up, but htough maybe you guys could ease my conscious...
Is ther something in the circuitry surrounding that specific preamp valve position that is causing the tubes to go bad...
Or is plain and simple bad luck and coincidenc, bad tube from the factory etc.
bear in mind the now defunct tube was only a few days old.
DrGonzo
Just tried another tube that was still good and also, microphonic as hell.
So perhaps its the actuall socket...
Am I damaging the tubes by placing them in this socket?
AlanRatcliffe
IDK, but don't take the chance. Power down and let a tech take a look.
petercornell
How old is the amp?
If the new tube is squealing in the same position, it could be a dry joint or a socket that needs tensioning, nothing major but still needing a bit of expertise.
Peter
DrGonzo
I took the amp to Jeremy in Plumstead and he had a look... It turns out the tubes and the sockets were fine, it was a grounding issue, bad soldering or something..
HE says its fixed and sounding boss... So glad!
