Author Topic: Replacing tubes  (Read 2019 times)

flanagan0718

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Replacing tubes
« on: December 08, 2018, 07:49:06 PM »
Hey guys,
I was playing guitar tonight and had a strange issue. The volume of my amp (Peavey Prowler) was swelling up and down on its own. Did the usual cable check and whatnot. Also determined that it was only after playing for 10 min or so. From what Iíve read it seems to be power tube related. Which makes sense.

My amp takes 2 x 6L6GC and 3 x ECC83S. What do you guys recommend. Iíve never changed tubes in this amp and am kind of looking for advice...thanks for reading / advising.
-Mike-


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woolie

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Re: Replacing tubes
« Reply #1 on: December 08, 2018, 08:08:37 PM »
Hey guys,
I was playing guitar tonight and had a strange issue. The volume of my amp (Peavey Prowler) was swelling up and down on its own. Did the usual cable check and whatnot. Also determined that it was only after playing for 10 min or so. From what Iíve read it seems to be power tube related. Which makes sense.

My amp takes 2 x 6L6GC and 3 x ECC83S. What do you guys recommend. Iíve never changed tubes in this amp and am kind of looking for advice...thanks for reading / advising.
-Mike-


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I just get whatever I can afford at https://www.tubesandmore.com


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ahiddentableau

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Re: Replacing tubes
« Reply #2 on: December 08, 2018, 08:30:17 PM »
Power tubes are perishable goods, so it could well be that they're starting to fail and need to be replaced (I'd want to be careful to rule out other causes first, though).  Your other tubes, on the other hand, can and probably will last for decades.  My deluxe reverb still has its original 12ax7s and 12at7s and it's more than 45 years old.  The idea that you should replace all your tubes is an old wives' tale made up by sellers to part you with your money.

Ralfg

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Re: Replacing tubes
« Reply #3 on: December 09, 2018, 01:31:50 AM »
Replacing power tubes in most amps requires that you bias them. I donít know if that amp is cathode biased or not, or how itís set up. So keep that in mind when you are going to do a power tube replacement.

Personally I like JJs for everything power tube.  And for 6L6 I also have used 6L6wxt+ and have liked them. I think... and mind you this is hard to tell... but the JJs I think have more umph.
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Aleph Null

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Re: Replacing tubes
« Reply #4 on: December 09, 2018, 04:51:11 PM »
I wouldn't expect to hear drastic differences between tubes or brands. Most tubes come from the same two or three factories. More "reputable" brands are usually better tested, so you should be less likely to get something out of spec. JJs and Electro Harmonix have both worked fine for me. Definitely determine whether the amp needs to be rebiased. If you take it to a tech to bias it, then you I'd buy my tubes from them.

gordo

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Re: Replacing tubes
« Reply #5 on: December 09, 2018, 07:38:20 PM »
Big JJ fan here but like ahiddentableau mentioned I wouldn't overlook an iffy solder joint somewhere, or even an oxidized jack.  Input jacks and, especially if you don't use them, the fx loop jacks are worth looking at.  If you can duplicate it and tap/push the circuit board with a chopstick it might point you in the right direction.

Or like you say it might be tubes...  The Prowler doesn't have adjustable bias so buying a matched pair of anything should just be plug and play.  It can be modded to include a bias adjustment but having done a bunch of Fender Blues Jr to "open up the tone" (customer's words) I don't know that I'd spend the time or money.  Prowler and the later ValveKing's are nice sounding amps.
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flanagan0718

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Re: Replacing tubes
« Reply #6 on: December 09, 2018, 08:17:04 PM »
Thanks for all the advice guys! Iíve done a bit of research and find that the amp does not have an adjustable bias. Iíll definitely open it up and check the solder joints and see if there are any iffy ones in there. Going on the fact that I have owned this amp for 6 years now and never replaced the power tubes, Iím thinking it may be a good idea to just plop a new set in there anyways. There are quite a few options for the 6l6 out there. Iíve always heard good things about JJ and Ruby. I also found a set of Peavey tubes too. Assuming they are all pretty similar I may go with the Peavey tubes or the JJ like other have recommended. Still looking for input, feel free to post it.


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Ekimneets

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Re: Replacing tubes
« Reply #7 on: December 10, 2018, 02:08:37 PM »
Thatís funny, because Iím having the exact same issue with my Vox Night Train 15. I have checked the guitar jack, switched guitars, swapped cables, everything within reason and there is just this odd, seemingly random fluctuation in the volume.

I definitely try replacing the power tubes.

-Mike
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Ekimneets

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Re: Replacing tubes
« Reply #8 on: December 10, 2018, 03:21:15 PM »
 Nothing like an easy fix.

 Apparently I was even the line with the universe because I pick the right tube on the first try. Awesome.

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flanagan0718

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Re: Replacing tubes
« Reply #9 on: December 10, 2018, 03:25:17 PM »
Nothing like an easy fix.

 Apparently I was even the line with the universe because I pick the right tube on the first try. Awesome.

-Mike


Nice good to hear!!


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Ekimneets

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Re: Replacing tubes
« Reply #10 on: December 10, 2018, 03:34:12 PM »
Thx Flanagan, I was pretty happy myself.

-Mike
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thesmokingman

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Re: Replacing tubes
« Reply #11 on: December 10, 2018, 04:31:41 PM »
no adjustable bias?
try contacting the tube vendor about the specific brand of amp you've got for a matched set. this is what the mesa guys have to do if they don't want to buy Mesa tubes and generally tube vendors know this and accomodate. that said, vintage amps rarely had bias adjustment (or even matched tubes) so even if you just end up getting a matched set of tubes you're doing just fine.
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flanagan0718

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Re: Replacing tubes
« Reply #12 on: December 10, 2018, 05:02:08 PM »
no adjustable bias?
try contacting the tube vendor about the specific brand of amp you've got for a matched set. this is what the mesa guys have to do if they don't want to buy Mesa tubes and generally tube vendors know this and accomodate.

Huh this kind of makes me second guess the JJs I ordered. There were those and a Peavey set for 5 bucks more. Maybe I should have just ordered the Peavey ones


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gordo

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Re: Replacing tubes
« Reply #13 on: December 10, 2018, 06:00:25 PM »
Nope, you'll love the JJ's.
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flanagan0718

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Re: Replacing tubes
« Reply #14 on: December 10, 2018, 06:59:35 PM »
Nope, you'll love the JJ's.

I just pulled the tubes out to have a look at them and it already has JJs in there. Haha


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