replacing tubes...

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Hold 'Em Czar
Member Since: Dec 30, 2004

ok i've managed to burn out a power tube of my mesa dual rectifier...the tubes are EL-84's anyone know a good place to get replacement tubes?

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I am not a crook's head
Member
Since: Mar 14, 2003


Jun 10, 2005 08:10 pm

I read good things about this site:
www.eurotubes.com/index.htm


But I have never dealt with them. Matter of fact, I haven't bought tubes yet, although I'm almost ready. The crappy Sovtek tubes that my amp came with are just about done. I can't wait to put nicer tubes in it and see how it sounds.

All I know is stay away from Sovtek/Groove Tubes (groove tubes are just rebranded sovtek tubes). JJ Tubes get rave reviews from what I read.

Prince CZAR-ming
Member
Since: Apr 08, 2004


Jun 11, 2005 08:52 am

Here's another one that's good.

www.kcanostubes.com/content/

be sure to ensure that the amp is biased correctly, i'm not sure of the DR but lots of amps need to be biased when replacing power tubes. Some do not, though I'd make sure your DR doesn't before assuming. Non biased output tubes can cause bad tone, short tube life, burnt output transformers, and other not-niceties.

I thought the DR was higher power than an EL84. I was under the impression it ran EL34. I could be wrong of course, just didn't want you to get the wrong tubes.

The old Svetlana company is making some nice EL34. I believe they're SED or something like that. The winged C logo, anyway. But I don't think they make EL84, JJ/Tesla is good, from what I've heard as well.

Sovtek is making some decent preamp tubes, but I don't think the output tubes are getting much favor (to concur with Tadpui).

I am not a crook's head
Member
Since: Mar 14, 2003


Jun 11, 2005 09:41 am

Oh man I got to shopping around on the Eurotubes site and they have a full retube kit for my Traynor YCV80...all 7 tubes for $85! That's an amazing price...I was prepared to spend like $50 on just a pair of power tubes.

Also here are his options for retube kits for the Dual Rectifier:

ssl.eurotubes.com/cart/in..._category_id=29

Although surely you can just buy only the tubes that you need to get back up and running.


Its pretty cool that you can describe to him what kind of sound you're after and he can hand pick tubes to match your specs. I think that I know where I'll be going to get new tubes.

Hold 'Em Czar
Member
Since: Dec 30, 2004


Jun 13, 2005 11:09 am

sweet links guys....after further investigation, we're thinkin' it's the preamp tube (although there is a power tube that looks differently (glowing wise).....i think we're just gonna send it back to Mesa...

www.TheLondonProject.ca
Member
Since: Feb 07, 2005


Jun 13, 2005 11:23 am

Hey Tadpui, I see you have a Traynor YCV80. How long have you had it? Is it holding up well? Have you had to change the tubes in it yet? How long do the tubes last? I've got the YCV40 and I totally love it but I've only had it for a short while so I don't know what to expect down the road.

What indicators are there that the tubes are going? Do they fail slowly or burnout like a lightbulb? Should I have an extra set of tubes around just in case? What can I do to extend the life of the tubes (if anything)?

Sorry for all the questions. This post started short but I guess I really don't know anything about tubes.

I am not a crook's head
Member
Since: Mar 14, 2003


Jun 13, 2005 11:37 am

Its OK BH. This is my first tube amp also, so I still have lots of questions myself.

I can tell ya what I've learned in my obsessive quest for info about my amp and tube amps in general:

- My amp has help up very well, but I'm not a gigging musician. It's been on 2 or 3 road trips, other than that it sits in my closet/isolation booth. I play it anywhere from 2x per week to every day, from 30-60 minutes at a time. So it still gets a pretty good workout, and it's held up extremely well. My only gripe is that it is rattly. I've heard that some of the cheap Sovtek tubes actually rattle (not sure what part tho), and the cabinet itself had some loose screws when I got it that I tightened up. My amp will be 2 years old in November.

- I haven't changed tubes in it yet, and I probably won't stray from stock tubes until after the 2 year warranty is over, just so I can get them replaced for free (yes, the warranty even covers the tubes!).

- Tubes slowly die, just like the CRT in your television. If you have a really old TV around the house, you can notice how the picture quality gradually degrades and eventually dies altogether. There are some conditions that will cause a tube to die suddenly, like breaking the filament inside (like a light bulb that takes a big knock), or if it goes microphonic (your amp will sound like its feeding back, either squealing or roaring uncontrollably). Just be sure to warm up the tubes for at least 1 minute by leaving your amp in standby, each time you turn on your amp, before putting any signal thru it. Also NEVER move a tube amp while the tubes are still hot...let it cool before moving it, and especially don't take it out into the cold air while the tubes are hot. Following those few guidelines will prolong your tube life.

- If you're a gigging musician, it's a good idea to replace power tubes 1 or 2 times a year (yikes!), and preamp tubes every 1 to 2 years. For a bedroom guitarist like myself, there's no reason that a set of power tubes won't last for 2 years, and preamp tubes will last quite a bit longer. But like I said, my amp doesn't move much, and only goes through about 4 or 5 hours of use per week, tops.

- If you gig with the amp, then DEFINITELY have either a backup amp or a spare set of tubes handy. Or at least a spare power tube and a spare preamp tube.

WYD, I do have 1 power tube that doesn't glow like the others also. there are 4 power tubes, and one of the middle ones doesn't glow like the others. I know that different tubes in different positions have different functions for the tone and performance of the amp, so I'm not sure if its a problem or not. The clean channel does sound like *** now, tho, so I'm pretty sure that it's a tube associated with that.

www.TheLondonProject.ca
Member
Since: Feb 07, 2005


Jun 13, 2005 11:51 am

Thanks a lot Tadpui. My usage scenario is much like yours. Mine pretty much sits in the same spot all of the time. I'm not gigging at all but it always seems to be so rare when all of my jammin' buddies get together that if my tubes failed when we were all together, I would be very dissapointed. It may be worth while to have an extra set around just in case. The only thing is, if the warranty is going to cover the tubes for the first 2 years, then I probably shouldn't change them myself if they fail during this time. I bet it would void the warranty.

The only rattling that I hear come from my amp is not while i'm playing but when I move the amp. Even if I am very gentle with the amp, I can still hear what sounds like "springs" when I set it down. Not sure if this is normal.

Thanks a lot for the info.

I am not a crook's head
Member
Since: Mar 14, 2003


Jun 13, 2005 11:57 am

Yeah, these amps use what's called "long spring" reverb units. The rattling you hear when you jostle your amp is just the reverb springs. I guess that since the reverb springs are longer, they tend to rattle more easily. Mine does it too, but these amps have AWESOME reverb, don't they?

Hold 'Em Czar
Member
Since: Dec 30, 2004


Jun 13, 2005 11:59 am

yeah man thanks....i've only had this one for about 2 months now, and it just started cracklin' and poppin' as if i was turning a dirty volume pot...only this thing did it with all knobs zeroed out and nothing plugged in!! it has kinda stopped now, so i donno what to do. it's prolly my fault cuz i never really let it warm up, i just switched the power on, then switched the standby off...i WAS thinkin' the standby was there just so you don't send a signal to it right when you turn on the power....OH also one thing that makes me think its a preamp tube, is it did the same noize when i switched the rectifier over to solid state...

www.TheLondonProject.ca
Member
Since: Feb 07, 2005


Jun 13, 2005 12:02 pm

Oh ya, the reverb kicks ***. Actually, I find that when we are playing our own tunes, I hardly even use my effects pedals. I can get all the tone i need from the amp itself. Its only when we play cover stuff that I feel I have to bring out the pedals.

It surely is a great amp. Red Label Celestions too! Great value in my opinion.

I am not a crook's head
Member
Since: Mar 14, 2003


Jun 13, 2005 12:02 pm

If it makes the noise with the volumes all at zero, I'd bet that its a power tube. But, I'd take an amp tech's advice over mine any day!

Mine did the same thing...crackled and popped. I took it in to the shop and they couldn't get it to do it. I got it home and it did the same thing. Turns out it was a combination of bad grounding in my house and an aging pedal input jack. Makes me want to get a power regulator, because the wiring in my house sucks!

I am not a crook's head
Member
Since: Mar 14, 2003


Jun 13, 2005 12:07 pm

absolutely, BeerHunter! I think its the best value in a tube amp in the universe. I'm totally sold on the Traynor brand. Mine has Celestion seventy / eighty speakers in it. 2 x 12", I believe. I'd be curious to hear the difference in speakers.

I got the 80W version only because it had the clean channel expander and brightness switches, plus the scoop setting (which actually sounds great when you crank up the mids to compensate, it adds beef without sounding hollow in the mids). Plus it had a speaker emulated direct out with speaker defeat and trim pots for the effects in and out. I couldn't see all of those features on any other amp in the series, but 80 Class-A tube watts is incredibly freaking loud. With the master at 5 or 6, I can nearly shake my house apart. I'd love to have a 40W YCV40 like yours so that I could crank it to get that great power tube saturation at more moderate volumes.

Prince CZAR-ming
Member
Since: Apr 08, 2004


Jun 13, 2005 12:43 pm

WYD, i'm curious as to the switching of the rectifier. was this done by a tech? was it biased afterwards?

If it wasn't biased, then you'll be running different voltages, which makes for different bias current in the tubes. Even if it's cathode biased (don't know, as I don't know what you have) the voltage (and current) will change, thereby changing the optimum range of operation for your tubes.

Also, I'm curious as to which solid state rectifier you're using. Webervst (www.webervst.com) has copper cap rectifiers. They replace the tube equivalent, but still have the same characteristics as the tube it replaced, i.e. voltage drop at high current, as well as slow warm up.

Also, the standby is for what you've mentioned. When turning on a tube amp, the heater current (low voltage) is sent right away to the tubes, but with the standby enabled, there is no high voltage going to the tubes yet, so the tubes can warm up. If you turn on the standby right away (withing 10 seconds) then you can strip material off the cathode of the tube (called cathode stripping). This will greatly shorten the life of the tube, and/or affect the tone.

as a side note, some tube rectifiers will slowly starting giving high voltage to the rest of the tubes. Like in a GZ34, it takes about 7 or so seconds for the rect tube to send out high voltage. This lets the other tubes warm up first, also gives the other tubes a slower ramp up of high voltage. The copper cap does the same thing, if the original tube it was patterned after has this function. (not all tube rectifiers offer a slow warm up)

Tad: if you can get another known working preamp tube, you could swap it out for your clean channel preamp tube, to see if it's the preamp tube. If the amp doesn't sound like poo in the 'non-clean' channel, then it's probably the clean preamp tube.

I had a input jack that made the whole amp snap crackle and pop. what a joy that was to find. Also on older amps, resistors can start to go south and you can get static and pops like that.

edit:

www.webervst.com


I am not a crook's head
Member
Since: Mar 14, 2003


Jun 13, 2005 12:54 pm

pjk: It's a power tube that's not glowing, and I'm not sure if that's normal or not.

Also, I think that the Mesa Dual rec. use a solid state rectifier for one channel and a tube one for the other channel. Not totally sure though.

Prince CZAR-ming
Member
Since: Apr 08, 2004


Jun 13, 2005 01:19 pm

yeah, i got that part, but wasn't directly addressing that. If both channels are nasty, then I'd say it's probably the power section. If it's only one channel, then I'd guess it's a preamp tube.

As for the one power tube not glowing, is there any heater glow (usually two orange lines down the length of the center of the tube). If not, then there's certainly some major problems. No heater current will mean no normal operation at all, thus killing the tube if it's still decent (the lack of heater current could come from bad wiring on the socket). If there's heater glow, but not any other type glow, then it may or may not be a problem. Some tubes glow more than others, some don't at all, some do a lot. Did the target tube change it's glow characteristics? or was it always like this? Also, you can switch around your power tubes without problem. They are all operating under the same parameters. Switching them around will tell you if the problem is with the tube, or with the socket and circuitry.

Prince CZAR-ming
Member
Since: Apr 08, 2004


Jun 13, 2005 01:21 pm

oop, that may be only one orange line for a power tube.

I am not a crook's head
Member
Since: Mar 14, 2003


Jun 13, 2005 01:29 pm

I think I'll take it to the tech and let them do it...I'm afraid that any tinkering on my part will void my warranty. Now I have to dig up that receipt again...

Hold 'Em Czar
Member
Since: Dec 30, 2004


Jun 13, 2005 02:05 pm

yeah there's a switch on the back to switch between solid state and tube rectifier....

i'm using a 2x12 mavrick like this one at the top

www.mesaboogie.com/Produc...k/maverick.html

I am not a crook's head
Member
Since: Mar 14, 2003


Jun 13, 2005 02:24 pm

wow, that looks like a really nice amp. When I think of Mesa Boogie, I think of mid-scooped nu-metal heavy metal guitar. But that amp looks awesome as a vintage-style bluesy amp. Do I even want to know how much it cost?

I bet that's a loud 35 watts, with 4 EL34s powering it!

Prince CZAR-ming
Member
Since: Apr 08, 2004


Jun 13, 2005 02:26 pm

good deal, that would do the trick.

i guess they are el84. shows how much i'm keeping up =)

Prince CZAR-ming
Member
Since: Apr 08, 2004


Jun 13, 2005 02:27 pm

that's what I was thinking of too, very nice WYD.

Musical Philanthropist
Member
Since: Nov 11, 2004


Jun 14, 2005 03:55 pm

WYD . Check some old electronics stores they might have a tube tester and you can narrow it down that way. We have one at work and there have many times I thought I had a bad tube and it turned out to be something else.

Hold 'Em Czar
Member
Since: Dec 30, 2004


Jun 14, 2005 04:02 pm

cool idea! i didn't know those even existed....will do some research!

thanks man!

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