#1
I noticed today that one of the power tubes in my Tweaker wasn't glowing. I'm still getting sound, and my amp works properly. The only thing I've noticed about it is that the volume knob increases the output only slightly until I get to about 12 O'clock, then all of a sudden it gets louder much more quickly. I've had this happen on other amps before, so I'm not sure if this is an actual problem.

I've been reading as much as I can find on forums about why this happens, but there are varying opinions. I bought this amp new less than a month ago, and the store has a 30-day guarantee policy so if one of the tubes is bad already I can probably get another set of tubes for free.

I'm wondering if the tube that isn't glowing is loose or something. I know that tube amps carry a lot of voltage and such, so I unplugged it from everything (power source, cab, guitar) earlier today.

Thoughts on why the tube isn't glowing? Any way to check the tubes myself? Any other advice?

Thanks, guys
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Quote by Jackal58
Yer pretty fly for a Canadian.
#2
greg has one of these amps as you may know. he may have an idea. I would just check to make sure they are all seated down properly and nothing is loose. you can also try swapping the power tubes around. See if it follows the tube or the socket.

If it still does not light up after that then replace it under warranty - try to stay away from shipping amp off for repair and waiting 3 weeks.
#3
Thanks 311. I'll check to make sure they're seated properly and let you know if that makes any difference. If not, I'll post some pics.
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Quote by Jackal58
Yer pretty fly for a Canadian.
#4
I just swapped the power tubes, but still only one is lighting up. It seems to be following the tube. I'm going to switch them back again in a little bit just to be sure. I've included pictures of pretty much everything: tubes, socket, tubes in amp, tubes in amp when turned on, and pictures of the tops of the tubes so you can see the one glowing. The pics were taken with my iPhone, sorry for the not-so-great quality.

The one that is glowing appears to be fine. It's glowing a nice orange colour, although the lighting in the one pic makes the tube look red. The other tube that isn't lighting has some speckles on the top of it. When Egnater re-branded them, they coated the tubes in something pretty dark, and it's hard to tell whether the speckles are from the coating, or if it's something going on inside the tube. Not sure if you can see this from any of the pics, but from what I understand spots like that can mean the tube is dead.

When I played through it after the tube swap, it was still working fine. From what I understand, the power tubes work in pairs and if one is blown it should be pretty obvious by the sound of the amp (popping, high-pitched hissing, no sound at all, etc). Could the amp still be producing a good quality sound if the one tube is done?

I'm going to call the store I bought it from and see if they can ship me some new tubes. Maybe I'll try to get some EL34s instead of the 6V6s. I've heard they make this amp sound even better! I'll let you guys know what happens.

Until then, any other thoughts?





Fender American Vintage '62 Stratocaster
Gibson Les Paul Custom
TC Electronic Polytune
Danelectro Blue Paisley
EHX Big Muff Pi w/ Tone Wicker
Dunlop Crybaby
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Egnater Tweaker

Quote by Jackal58
Yer pretty fly for a Canadian.
#5
well they're so dark... is it hot when you touch the tube after a few mins? or is it colder than the other one?
Call me "Shot".

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#6
Yea, the coating on the tubes is really dark. The only glow you can see on them is right at the top.

I didn't check the temperature. I've read you shouldn't touch the tubes with your hands because of the oils. I could try it out with a thin towel or something though.
Fender American Vintage '62 Stratocaster
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Quote by Jackal58
Yer pretty fly for a Canadian.
#7
yeah, some people swear by it. but from my experience touching all these tubes (although i use a kleenex when handling NOS tubes) i cannot get them to break. my tungsol/JJ 12AX7s had so many fingerprints on it, played to death, and fed with decent voltage, they didn't break.

oil + hot temp + vibration supposed to = crack in the glass.
Call me "Shot".

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Est. 2007


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#8
I felt the tubes through a Kleenex to gauge temperature. The one that's lighting up felt warm after a couple minutes; the other one was still cold. So it's a bad tube then?
Fender American Vintage '62 Stratocaster
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Dunlop Crybaby
EHX Deluxe Memory Boy
Egnater Tweaker

Quote by Jackal58
Yer pretty fly for a Canadian.
#10
Ok, thanks for your help everyone.

I just switched the tubes around again, and it's definitely the tube, not the socket. I called the store I bought it from and they said they'll make it right. They wanted me to bring or send the amp in for them to fix, but I took 311's advice and asked them if they could just ship some tubes to me. The told me to e-mail the store's manager and ask him, so hopefully he's OK with that.

Any idea why the amp isn't acting up if one of the tubes is bad? Is it safe to play through, or should I just let it be for now, until I get the replacement tubes?
Fender American Vintage '62 Stratocaster
Gibson Les Paul Custom
TC Electronic Polytune
Danelectro Blue Paisley
EHX Big Muff Pi w/ Tone Wicker
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EHX Deluxe Memory Boy
Egnater Tweaker

Quote by Jackal58
Yer pretty fly for a Canadian.
#11
Not sure if new tubes will fix the problem. My fear is that the problem will still be there. Yes they do run in pairs (class A/b) so the fact that one is not working may be a problem with the socket or heater. Really not sure.

I probably would not play the amp like that unless it has a half power switch or something. I don't remember.

Greg?


Also, maybe ask in the Egnater thread
Last edited by 311ZOSOVHJH at Jul 30, 2010,
#12
Quote by 311ZOSOVHJH
Not sure if new tubes will fix the problem. My fear is that the problem will still be there. yes the do run in pairs (class A/b) so the fact that one if not working may be a problem with the socket or heater. Really not sure.


I switched them a couple times, and every time I switched them it was the same tube that wasn't glowing. Shouldn't that rule out the socket?

I'm not sure how a heater works, exactly, but I'm going to assume it's what heats up the tube and causes it to work . And since I don't really know how it works, I'm going to also assume that there's not an easy way for me to check this out.

I'll post a link to this thread in the Egnater thread, as well.
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Egnater Tweaker

Quote by Jackal58
Yer pretty fly for a Canadian.
Last edited by Jimmy_Page_Zep at Jul 30, 2010,
#13
^sorry.

good point. I was distracted. Yes, if the problem follows the tube and the other tube works fine in that socket then it is probably a bad tube.

Good call. New tubes should fix ya' up. Let us know. We don't like downed Tweakers


Yeah - I'd go for EL34s if they will let you. Unless you want to get as close to Fender tones as possible ELs are the way to go imo.
Last edited by 311ZOSOVHJH at Jul 30, 2010,
#14
It's not really "down". It still plays perfectly, which I find pretty strange with a blown tube. I definitely want to try out the EL34s because everyone seems to really like them in this amp. I use both the US and UK voicings equally depending on the day. Ideally I'd like to have a Fender-like clean tone with a Marshall grit. Maybe I should just get another Tweaker and use an A/B switch to go between them

If I were to go for more Fender tones, would the Tweaker be able to handle 6L6s? From what I've read, you can swap out different types of tubes without re-biasing. I know you can swap out for EL34s, but not for EL84s. I haven't heard of anyone trying out 6L6s though. I think I'd have to take off the top grill to make them fit in the chassis, though. Anyone tried this out, or see a problem with doing it?
Fender American Vintage '62 Stratocaster
Gibson Les Paul Custom
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Danelectro Blue Paisley
EHX Big Muff Pi w/ Tone Wicker
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Egnater Tweaker

Quote by Jackal58
Yer pretty fly for a Canadian.
#15
^I'm pretty sure it does, yes with no biasing.

We really need Greg in here

He swapped from El34s to 6L6s right in front of me and we played on. Noticeable.

Yeah you'll need 2 Tweakers to switch back and forth on the fly


#16
Quote by 311ZOSOVHJH
^I'm pretty sure it does, yes with no biasing.

We really need Greg in here

He swapped from El34s to 6L6s right in front of me and we played on. Noticeable.

Yeah you'll need 2 Tweakers to switch back and forth on the fly




Awesome. Thanks man, you're a huge help! I found a few forums with people who have swapped for 6L6s and EL34s. Opinions seem to vary on which is better, but it seems everybody agrees that they're both better than the stock 6V6s. And they both fit in the chassis with the top grill on, but you need to take it off to put them in.

I may end up getting a second Tweaker to switch back and forth eventually, if I need multiple channels for gigging in the future. For the price, it would be a great idea. Maybe I'll even get a 3rd for some Vox cleans too
Fender American Vintage '62 Stratocaster
Gibson Les Paul Custom
TC Electronic Polytune
Danelectro Blue Paisley
EHX Big Muff Pi w/ Tone Wicker
Dunlop Crybaby
EHX Deluxe Memory Boy
Egnater Tweaker

Quote by Jackal58
Yer pretty fly for a Canadian.
#17



Hey, after some further research I cannot for the life of me find that you can use 6L6s. I thought for sure either Greg had some or I read it somewhere.

Either way, get the EL34s. You can always get a decent 6V6 or 6L6 pair later to fool with. Also, maybe they won't make you send the old tubes back so you may have at least 1 good one. Maybe match that up to the old one and buy 1???
#18
^
You were right. Here's Greg's NAD. He tried it out with 6L6s.

https://www.ultimate-guitar.com/forum/showthread.php?t=1313406

I found a few threads in various forums. In the first one, the guy had the same problem as me, with one tube not glowing. Quote from the first link:

Egnater has stated that the Tweaker can be run with 6V6GT, 5881, 6L6GC, EL84, KT66, and KT77 tubes. It is a cathode biased amp, so there is no bias pot to adjust. This doesn't mean the bias will be "optimal" for all of the tubes, but they can all be run in the amp.

http://www.thegearpage.net/board/archive/index.php/t-730435.html

http://www.thegearpage.net/board/archive/index.php/t-694332.html

http://www.andersonforum.com/board/showthread.php?t=7346

http://www.tdpri.com/forum/archive/index.php/t-195324.html
Fender American Vintage '62 Stratocaster
Gibson Les Paul Custom
TC Electronic Polytune
Danelectro Blue Paisley
EHX Big Muff Pi w/ Tone Wicker
Dunlop Crybaby
EHX Deluxe Memory Boy
Egnater Tweaker

Quote by Jackal58
Yer pretty fly for a Canadian.
#20
Hey everyone, just thought I'd give an update on the situation.

My new Groove Tube EL34s came in from Twelfth Fret today! I know GT rebrands their tubes, so I checked out the product number (GTE34LS) and it turns out that these are re-branded JJs. Since Tweakers are magical amps, you can just swap between different types of tubes without rebiasing (I swapped from the stock Ruby 6V6s). It was really easy, although at first it looked like I didn't push one in all the way because it seemed to be sitting higher. I checked it out and they were both installed properly, sitting flush to the socket. After comparing the two tubes side by side, I noticed that one was about 1/2" taller than the other. I doubt this is much of a problem, except I can't put the metal grille back on the top of my amp because of the taller tube. But I can deal with that for the sake of tone.

As soon as I turned my amp on, the sound difference was incredible. I didn't have anything against the 6V6s; they sounded alright and it was really easy for me to dial in tones that I liked. The EL34s, however, sound more full and much better. Way more bass. My amp was already on the Brit voicing, so I switched between "Deep" to "Tight" to kill the excess bass and adjusted the EQ to taste. I also experimented with rolling the bass down on the amp's EQ as well, but switching to Tight sounded better to my ears. I find that the EL34s don't break up as early as the 6V6s did but still sound angrier, which I like. They're giving my amp a warmer, fuller sound, especially on the Brit voicing.

I messed around in the US and AC voicings as well. US sounds really good, a little bassier than before. I didn't really like what the EL34s did to the AC voicing though. It sounds kind of weak now. This is probably the only thing that I prefer with the 6V6s so far, but I really didn't spend much time on AC. And since I spend most of my time on the Brit setting, I doubt the 6V6s will get much use now.

Sorry for not posting any sound clips, I'm still saving up for a mic. I promise that I will put up clips of the 6V6s and the EL34s for comparison as soon as I buy one.
Fender American Vintage '62 Stratocaster
Gibson Les Paul Custom
TC Electronic Polytune
Danelectro Blue Paisley
EHX Big Muff Pi w/ Tone Wicker
Dunlop Crybaby
EHX Deluxe Memory Boy
Egnater Tweaker

Quote by Jackal58
Yer pretty fly for a Canadian.
#21
^glad it worked out for you thanks for the update.

Can't speak to one EL34 being higher than the other but yes you cannot put the top grill back on with those suckers in there. I played Gregs with EL34s and was pretty impressed as you know. Cool thing is you can pop those 6V6s back in there at anytime without biasing and flip back n forth.
#22
Some tubes are like that. The glass envelopes are different heights. I've never seen JJs like that though. Only Shuguangs.
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