Hi to all!
I bought an EL34 push-pull 35wpc almost 2 months ago from a shop in Park Square which was traded in for a higher model aftr 6 months of usage. I hooked up my hard to drive 87dB AR93 and observed it had trouble driving these speakers. There was a little bit of distortion at only 9-10 o'clock volume level. But, what really troubled me, after 2 days of listening to it, was when one of the output tubes on the left channel glowed like a light bulb followed by a cracking sound from the speaker. I thought it will blow ,so, I turned it off immediately. It happened once again but this time on the right channel. At the back of my mind, it might be the speakers. But, I used to have a 30wpc Rotel which drove these speakers with ease.
I brought the amp to their shop to have it checked. After 3 days, I was told that the on/off switch was intermitently losing contact which affected the circuitry and was replaced. 2 days after, the new switch won't go on "OFF" mode. When you turn "OFF" the unit it goes back to "ON" position, the locking mechanism in it I presume. I brought it directly to the factory for another check up. The switch was replaced then a capacitor was added. I also replaced my ARs with a pair of 91dB B&W floorstanders for good measure. I love the sound coming from the B&Ws and I thought these were a perfect match. Alas, it happened again last night just after 2 weeks of audio bliss. By the way, the "new" switch is back to its old unreliable state, on "ON" position for all eternity a day or two after replacement. I use my avr as the on/off switch ever since.
What could be the problem here? Is it just the switch? It's intermitent in nature, but, hey, it's next to impossible to have your eyes glued on the amp the whole time you're listening. What if you need to piss? It happens very fast.
It's my first dive into tube gear and I'm extra careful but really frustrated at this point. You, the tube gurus, might have a different opinion or the same experience on this matter. Hope you can help a pi**ed off newbie here.
Thanks.