Need help with Twin Tube Classic

severthee

New member
Good day,

I'm new to this forum, and Im not sure where to post this. Ive already sent email direct to the site but i havent received any response. So here goes...

The first time I plugged in the Twin Tube, i thought, wow these mini-tubes can really sing huh? I really liked how the Rhythm channel sounds, almost like an amp breaking up. after awhile, I noticed that the volume of the rhythm channel became soft. so instead of getting unity somewhere around 10 oclock, the effect only becomes audible at 1oclock. weird. I stepped on the lead channel, and its still fine. unity somewhere around 10 oclock. I checked the demo videos at proguitarshop and noticed my rhythm channel has become really weak compared to the demos.

I though my tubes were busted so I ordered replacement tubes at tubedepot. They sent me Raytheon tubes, ive already installed them here, theyre the ones with the orange markings...

http://i70.photobucket.com/albums/i120/severthee/ax/IMG_2641.jpg

I let the tubes warm up for 5 mins. Tried them and I guess I was back in business, my gain seems to be back to normal. sweet OD. After a few days, I tried plugging to it, and I noticed my gain was not that edgy anymore. at around 10-11 oclock I can barely hear anything. The Rhythm channel only starts to sound at 1 oclock, and gets dirty at 3oclock. Its like all the effect was crammed up on the right side of the knob, but without getting a good crank when maxxed. Too bad Im located offshore and cant really send my unit to seymourduncan. Emailed them my problem and requested for new tubes. They sent me the stock tubes Jan Philips. Theyre the ones with the blue and yellow markings on the picture above. Ive installed them here on the following pictures

http://i70.photobucket.com/albums/i120/severthee/ax/IMG_2642.jpg

http://i70.photobucket.com/albums/i120/severthee/ax/IMG_2643.jpg

Turned on the pedal and let it warm up a bit..wow they sounded better than Raytheon. I dont know if they really do or the previous tubes were just busted that Im not able to compare them well before they broke. So I closed the pedal with relief. I was excited to bring it in a practice jam. The day came, plugged into the Twin Tube, I even let it warm up for 5mins and... i was back to the same soft volume and weak gain. back to square one, my volume is same with bypass only when Im around 12 to 1 oclock. Gain seems softer now.

I dont get this thing. Its only affecting the Rhythm Channel, and thats actually my favorite channel. The Lead channel is working well the first time, 2nd time when I retubed and even on the 2nd retube. the Lead channel didnt became weak or anything. But i dont want to tone down the Lead channel just to simulate the Rhythm Channel. Id rather have two different sounding channels. Shouldnt these tubes last longer than 12ax7? Im not even sure if the pedal's the one who's killing these tubes. Am I doing something wrong here? Do I need to bias these ? because I thought all I ve to do is change them tubes.

I appreciate any inputs on this. thanks
 
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Re: Need help with Twin Tube Classic

Patience. They WILL respond. The SD crew just returned from Musimesse in Germany.

I haven't experienced your problem. Whenever I have had any other issue, though, SD has made it right.
 
Re: Need help with Twin Tube Classic

sounds to me that something in the circuitry surrounding the tubes is frying them ...
good luck
t4d
 
Re: Need help with Twin Tube Classic

thats what i think too. though im still hoping i get help from seymourduncan techs here.
 
Re: Need help with Twin Tube Classic

One word comes to mind... voltage. Is the power where you're practicing consistent? Maybe there's a problem with the voltage going to the pedal. I'm no tech, but that's a good place to start.
 
Re: Need help with Twin Tube Classic

I'm using the adaptor that came with it. If voltage is the issue, i think i should also have faulty Lead channel. but in my case, the Lead channel works perfectly. thanks
 
Re: Need help with Twin Tube Classic

anyone can point me which resistor/cap combo deals with the gain of the rhythm channel? i might be able to fix this if i can tweak those values
 
Re: Need help with Twin Tube Classic

Hmmm--I`ve sent a few emails to the SD company and always recv`d a quick and helpful reply back from them. Try to contact them again if you feel it is necessary.
 
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Re: Need help with Twin Tube Classic

i tried resending.. still waiting. i hope someone points out the r/c combo for the rhythm channel so i can do this myself...
 
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