Help my Eartube has a hummmmmmmm!

[sc53]

I have been loving my Eartube and recently purchased some NOS 6N3P's from Jan for tube rolling. I got some Telefunkens and some Valvo/Amperex. I swear, I did NOTHING but gently pull out the stock Chines tubes and gently push in the Telefunkens, but ever since I did that, I have a horrible, quite loud hum in the left channel only. I have tried different interconnects, using the other set of inputs on the amp, switching power cords, switching outlets, and taking the amp out of the BPT power conditioner it was plugged into and plugging it directly into the wall, all with no effect. The left channel hum is \still there. I put the old tubes back in, no difference. I have somehow introduced a hum in my heretofore perfect amp! I emailed Jan but he is out of town for a few days. HELP ME so I don't miss my Saturday evening and Sunday morning radio shows, which I love to listen to through my phones while others are sleeping!
--Sarah

 

[sacd lover]

Quote:

Originally Posted by sc53 /img/forum/go_quote.gif I have been loving my Eartube and recently purchased some NOS 6N3P's from Jan for tube rolling. I got some Telefunkens and some Valvo/Amperex. I swear, I did NOTHING but gently pull out the stock Chines tubes and gently push in the Telefunkens, but ever since I did that, I have a horrible, quite loud hum in the left channel only. I have tried different interconnects, using the other set of inputs on the amp, switching power cords, switching outlets, and taking the amp out of the BPT power conditioner it was plugged into and plugging it directly into the wall, all with no effect. The left channel hum is \still there. I put the old tubes back in, no difference. I have somehow introduced a hum in my heretofore perfect amp! I emailed Jan but he is out of town for a few days. HELP ME so I don't miss my Saturday evening and Sunday morning radio shows, which I love to listen to through my phones while others are sleeping! --Sarah

Stupid question .... you turned off the amp when you switched the tubes didnt you?

Are the tubes pushed all the way into the socket; especially the left channel tube?

Try moving the tubes around and see what happens.

 

[sc53]

Yes I turned the amp off--but it hadn't been off for an hour or anything like some mfr's prescribe. Could I have blown a fuse of some kind? I have pushed and pulled and reinserted the tubes, they are well seated but still that damn hummmmmmmmm. You can even hear it over the music--UNACCEPTABLE! I have emailed Jan but will try to bring it in to a tube audio shop I know nearby. They sell lots of different cool tube amps and perhaps can work on my Eartube. Sob. I KNEW tube rolling was over my head!

 

[Balisarda]

Sorry about your troubles, Sarah! I can't imagine what's gone wrong, but Jan should be back from his trip tomorrow, and I'm sure he'll help you!

Let me add that I doubt the hum is any fault of yours, and I hope it won't discourage you from further tube rolling, which is one of the most fun (and expensive!) parts of owning a tube amp!

Enjoy your music,
Eric.