Gold Member Username: DmitchellOttawa, Ontario Canada Post Number: 4219 Registered: Feb-07 | One tube out the 8 EL84's I got today that I can't bias above 200mv (the recommended bias in 250 for Stingray). I've moved the tube to other sockets, and it's always the same. If I turn the trim all the way to max, it'll only bias at 200 mv max. Does this mean there's something wrong with the tube? |
Platinum Member Username: NuckPost Number: 15355 Registered: Dec-04 | I would hazard a 'yes'. |
Gold Member Username: DmitchellOttawa, Ontario Canada Post Number: 4220 Registered: Feb-07 | Me too. |
Gold Member Username: Stu_pittIrvington, New York USA Post Number: 3968 Registered: May-05 | I've never biased a tube, but if that's the only one that won't bias (in any spot) and the rest will, I think its safe to say its the tube. Do other tubes bias in that spot? |
Gold Member Username: DmitchellOttawa, Ontario Canada Post Number: 4221 Registered: Feb-07 | Yup, they all bias exactly where they should be. |
Gold Member Username: Stu_pittIrvington, New York USA Post Number: 3969 Registered: May-05 | Its kind of like changing your spark plugs, and one cylinder won't fire. You change where the cylinder where that spark plug is, and that cylinder doesn't fire. I'd be willing to bet it's the spark plug, but that's just me. |
Gold Member Username: DmitchellOttawa, Ontario Canada Post Number: 4222 Registered: Feb-07 | If you move it around, and the problem follows where you move it to, odds are its the tube (or sparkplug). I've already contacted The Tube Store to get a replacement. |
Gold Member Username: DmitchellOttawa, Ontario Canada Post Number: 4226 Registered: Feb-07 | The tube shop expressed me out a replacement tube the next day at no cost. Can't say enough good things about these guys. http://thetubestore.com/ |
Gold Member Username: DmitchellOttawa, Ontario Canada Post Number: 4250 Registered: Feb-07 | Man, my troubles never end. Over the last week I've noticed intermittent distortion in the left channel of my Stingray. I swapped around all the tubes, switched the speakers and even changed speaker cables. The problem is always in the left channel. Spoke to a repair guy here in Ottawa that was recommended on CAM, so the amp is going to him for a look. Hopefully it doesn't cost me too much fix. I guess the good news is they repair says tube amps are "easy to repair". |
Gold Member Username: MagfanUSA Post Number: 1579 Registered: Oct-07 | Please post back when the verdict is in. I'm curious to know if the bias adj prob and the distortion are related. |
Gold Member Username: DmitchellOttawa, Ontario Canada Post Number: 4263 Registered: Feb-07 | The amp is at the repair shop as of yesterday. The tech hasn't had a chance to take a look at it yet. Looks like I'll be without it for the weekend... bummer. |
Gold Member Username: SoundgamePickering, Ontario Canada Post Number: 1184 Registered: Jun-08 | Oh, that's crap Dave, sorry to hear about the troubles. You'll get 'er back - just hope it's a cheap fix. Hopefully, he'll give it a bit of a tune up at the same time, turn here, squeeze there. |