my Blues Junior is humming..loudly Why?

[vbf]

Hi everyone, Merry Christmas and JHappy Holidays to you all.

I picked up a used Blues Junior today and its humming pretty loudly at low volumes. The "fat" switch effects the humming loudness a well. It's used, about 3.5 years old, and is physically in excellent condition. I recently borrowed a friend's Blues Junior and it was very quiet.

Anyone have any idea as to the cause of the humming? Are the tubes bad?

I sure hope I didn't get a lemon!!

Thank you in advance,
Chris

[Jscrofani]

Could be the tubes!!!! I would start with replacing them!

[zb0430]

90 % of humming coming from tube amps is...

You guessed it, tubes...

I'd grab a few tubes, starting with the power tubes, and replace them. If you're unsure as to what you need to do, take it in to get looked at.

[Guitaardvaark]

what tune is it humming? maybe you can play along

[vbf]

Thanks...I'll replace them today. I've never had a tube amp before so this is new territory for me. You guys have been a big help...thank you.

[twang55]

Let us know the results, please. I'm having the same issues with mine.

Thanks.

[vbf]

Whereas only one of the smaller ones was bad, they were all old, I replaced them all. It still hums louder than I think it should, though. Deploying the "fat" switch makes it louder. I'll try it at church tomorrow and see how badly the sound guys screams at me (I mic it). The sound guy also happens to be a pretty good tech and may be able to troubleshoot if there's something wrong.

Hope this helps and will report back anything additional.

[HereIGoAgain]

Originally Posted by vbf

Whereas only one of the smaller ones was bad, they were all old, I replaced them all. It still hums louder than I think it should, though. Deploying the "fat" switch makes it louder. I'll try it at church tomorrow and see how badly the sound guys screams at me (I mic it). The sound guy also happens to be a pretty good tech and may be able to troubleshoot if there's something wrong.

Hope this helps and will report back anything additional.

Al tube amps will make noise to a point. If it's a "shussssssssssssssh" type noise, that's normal for the breed. If it's a "buzzzzzzzzzzzzzzzzzzzzz" or a "hurmmmmmmmmmmmmmm" then it could be a biasing issue.

Did you use a "matched pair" of EL84's when you re-tubed the power amp? If you did, maybe you need the amp re-biased.

[vbf]

Thanks, Matt. I did use a matched pair (groove tubes). I'll ask the sound guy at church to check the bias.

Thanks again,
Chris

[dwclayalt]

Originally Posted by vbf

Hi everyone, Merry Christmas and JHappy Holidays to you all.

I picked up a used Blues Junior today and its humming pretty loudly at low volumes. The "fat" switch effects the humming loudness a well. It's used, about 3.5 years old, and is physically in excellent condition. I recently borrowed a friend's Blues Junior and it was very quiet.

Anyone have any idea as to the cause of the humming? Are the tubes bad?

I sure hope I didn't get a lemon!!

Thank you in advance,
Chris

Chris,

I had a similar issue once and it turned out to be that the outlet I was plugging into was not grounded. Actually none of the outlets in the room were grounded, once I fixed this the loud hum went away.

Just a thought.

Wayne...

[12Stringer]

Originally Posted by dwclayalt

Chris,

I had a similar issue once and it turned out to be that the outlet I was plugging into was not grounded. Actually none of the outlets in the room were grounded, once I fixed this the loud hum went away.

Just a thought.

Wayne...

This is what I am thinking, ground hum. Try it at church, if it dont hum there, then its a ground hum, might be guitar or amp jacks, or the instrument cable.

[vbf]

As always, great replies from all..thank you very much. I took the amp to a place here in town that knows tube amps inside and out. The guy listened to it and said it was a normal level of hum. He also mentioned the grounded power supply situation. As suggested, I'll try it tomorrow at church and see how things go.

BTW, as a new tube amp user....what took me so long? This amp sounds phenomenal, especially with new tubes. I'm sold...never going back to solid state again.

[ljguitar]

Hi Chris...
My check list runs along these lines...

• Ground checked - and perhaps lifted
• Different cable
• Different guitar
• Orientation and distance from the amp
• Proximity of fluorescent lights
• Light rheostats not fully ''up'' or totally switched off

I'm not sure you told us what kind of guitar?

[JimmyG]

i have had one for many years. just recently i was jamming with some friends and experienced some awful humming.i turned the reverb down all the way and it stopped.i don't need it, i got all the reverb i need on the line 6 pocket pod.
but, i just wanted to say the blues junior is a thing of beauty, all that power from what is it 10 watts? great tube tone.anyone who owns a strat should have this amp.

[vbf]

The Blues Junior is 15 watts and sounds great. I play both a strat (w/Fralins) and Les Paul. The pickups in the Les Paul include a Seymour Duncan JB in the bridge and Seymour Duncan Jazz in the neck. I'll be curious to hear the differences between the two guitars vis a vis hum.