Another Tourmaster 4212 issue

[Sixtycycle]

Tonight my 4212 started to stop working or intermittenly working on OD 1 & OD 2...works fine on clean 1 and clean 2 no issues on those two channels. We thought we smeeled an aroma heat/melting plastic.
So I stopped and started to investigate pulled the back off. No real smell at that point. Looked around power tubes were all lit up pre's looked ok and a few were warm then i reached around and turned the standby back to play strummed and still only the clean channels are working contiued to lokk around and all of the sudden the OD channel started to work. I inplugged my rack and went straight in thinkin it was maybe in my rack and the OD channels went out again. I unplugge dthe footswitch and only had guitar and I was switching channels by hand at that point. Still no OD channels. all of the sudden the OD channels came back I then switched through the channels one at a time and they all stayed on and seemed to work fine. But when turn the volume on OD 1 it controlled not only its own but also OD 2's volume. OD2's volume controll does nothing. so what the hell has happened now???

Again to summerize:
Clean 1 works fine no issue.

Clean 2 works fine no issue.

OD 1 is intermittent overall, sometimes on, sometimes very faint to nothing at all, and OD 1's volume control controls the volume of OD 2 and OD 1 at the same time.

OD 2 is intermittent overall sometimes on, sometimes very faint, to nothing at all, and OD 2's volume has no effect on OD 2 or any other channel.

When OD 1 is intermittent so is OD 2 at the same time. So whatever has happened it effect OD 1 & OD 2 at the same time.

Gig comeing please help asap....once again Egnater is letting me dooooown

 

[Anonymous]

preamp tube #8, the PI tube is where i'd check first.

next, i'd go through the normal routine of trying different preamp tubes in slots 1-5 (even though i think slot 3 is a clean channel slot).

report back, or pm me

 

[Sixtycycle]

Thanks man! So you think this is sounding like a tube issue though? I tried to reproduce it today but of course but it worked perfect on all channels. I will see what happens with a new set of pre tubes from Dougs and go from there I guess and let ya know. Do you think the power tubes are ok though?
I appreciate as always your help!

 

[Anonymous]

no problem my friend!

hard to say FOR sure, without poking around in it with my limited knowledge to begin with, but, id say if cleans are working, then you have no issues with power tubes.

if you're wanting more of a high gain tone, try a sovtek 12ax7LPS for the PI slot, or if you're wanting a bit less gain and a tad more clarity, the mullard 12at7 (cv4024) can be had for around 20$.
i'd grab a few new 12ax7s from laura "valvequeen" on here, and try switching them out.

the chinese 12ax7b is a great all around tube, and this amp likes it. the jj ecc83s is a good v5 tube for the TM also.


i dont even think at this point you need a retube. just a new spare tube. put it in V1, then progress through v5.

 

[Sixtycycle]

Well here goes some more......So I finally get the amp to do the screw up again where the OD1 volume starts controlling the OD 2 volume and it only intermittently works on the vintage 1 and vintage 2. I see that 2 power tubes are lit bright orange all over. Quickly got shut down got all 4 power tubes out. Had my new set of JJ's waiting in their boxes and ready to go. So under some great advice Yeti advice, pulled the chassis and checked the insides for any other visual issues since there was a slight smell happening from time to time....Found nothing burnt or melty looking so I continued to check those screen res's and all read the same and looks fine. So I closed her up put the JJ power tubes in and biased. I went to rehearsing and all was great!! UNTIL our bass player and other guitarist thought they smelled something....we sniffed both of our 4212's (Yep I talked him into one too, since I had 2, also if you all remember my other one that Bruce and Nate left me in the cold on the transformer on my other one) Anyway seems to sound fine but it did smell after some rehearsing.... Now question, transformer was replaced by Nate on this one supposedly....guess I won't or don't know for sure. But what the hell else could be making the smell? Gawd in all my years I have never had any, A N Y piece of gear that has given me such headaches! Anybody got an Idea? Or just play it until it shows........ I'm on my own so any advice would be greatly appreciated.
Thanks

Egnater Boys I hope you read this and at least feel a little bit bad that 1 faithful Egnater consumer got 2 EGNATER TOURMASTER 4212'S that have been non stop piles of break down heartache.
Thanks.

 

[Anonymous]

wow. yikes. what can ya say.

the redplating power tubes is a dead giveaway that something is wrong. i personally dont use JJ 6L6 power tubes due to the high failure rate i've read about with the current production tubes they put out.....possibly those could be your problem?

other than that, i'd say your amp needs serviced.

 

[Sixtycycle]

Sorry I must have got ya confused in my ramblin.. ..the red plating tubes were the 2 outside Tung Sol power tubes that are about with about 250ish hrs on them, The JJ's are brand new and what I have put in there place. Update: 1/26 I went up to the rehearsal hall today and spent about 3 hours hammering on her and just putting it through the paces. Periodically watching the tubes, zeroing everything and checking the bias, then back jamming. Worked like a dream. No smells...no sounds....no problems...so I am guessing the following for now:
2 Power tubes shorted initially.
Smells must have been somebody maybe touching the power tubes getting some residue on them and it burning off???? ya got me.
I can't explain it Boys But I'll take for now.

 

[daviedog]

If a power tube fails, you would blow a fuse.
Data sheet 1980's sylvania 6L6GC...estimated life 10,000 hours.
You guys question the reliability of bottles? And not the amps?

 

[Anonymous]

If a power tube fails, you would blow a fuse.
Data sheet 1980's sylvania 6L6GC...estimated life 10,000 hours.
You guys question the reliability of bottles? And not the amps?

thats a rating for a VOS/NOS USA made tube.

i question the reliability of everything when it comes to this shit. preamp then power tubes first, as they are the easiest item to eliminate.

and, you dont always blow a fuse when a power tube goes.
prime example, peavey 5150's are notorious for screen grid resistors being taken out by a blown 6L6 and the amp still running.

so, yes, going back to it, a redplating power tube is again, A DEAD giveaway something is wrong.

 

[daviedog]

YES an str415 in my mesa boogie mk2b. 30yrs and still running.
I've read a lot of your posts. Your a nice guy, always trying to help lost souls.
So pissed off at Egnater. I intended nothing toward you you. Good nite mister..

 

[Anonymous]

YES an str415 in my mesa boogie mk2b. 30yrs and still running.
I've read a lot of your posts. Your a nice guy, always trying to help lost souls.
So pissed off at Egnater. I intended nothing toward you you. Good nite mister..

i try man, i do try!

wow, thats an old set of tubes. i bet your amp would benefit from a set of new ones though....unless you dont use them that often.

i understand. i channeled my anger and negative energy regarding this stuff the past two years, into learning as much as i could on my own about amps and shit like that....and i still feel like i know NOTHING other than my experiences. i was able to put a new power tranny, reverb tranny and do my own "m" mods among others to my tourmaster though.

my 5150 is heavily modded and stopped working right after i got it (2 resistors and a jfet went kaput!), and i was able to fix it myself with some help, and now, it has never sounded better. it's very 5150, but without all the flub and overwhelming gain. i feel comfortable saying i know enough about my 5150 and tourmaster amp to keep me from fucking them up now.

there's a handful of REALLY nice mods that can tighten both those amps up and really refine the gain in them, and i really have fallen in love with both of mine.

 

[daviedog]

I love peaveys. At least the American ones. I have a classic 30. Sounded fizzy and harsh. Did the Blue Guitar mods. Now one of my favorite amps. I read sheet music & do a few casual dates a month. Think weddings etc. Don't have much experience with the flame throwers you all use. Fun to read about though! Use a polytone minibrute for 'dates' which is solid state.

Got into amp servicing, at least mine, cause Miami is a waste land for amp servicing. No one no where..

Learned a lot about specific theory, but running about 30% in fixing my stuff. I still don't get the total picture of how the amps operate. Should get off my ass and learn ohms law. And how to really use it!

 

[Anonymous]

I love peaveys. At least the American ones. I have a classic 30. Sounded fizzy and harsh. Did the Blue Guitar mods. Now one of my favorite amps. I read sheet music & do a few casual dates a month. Think weddings etc. Don't have much experience with the flame throwers you all use. Fun to read about though! Use a polytone minibrute for 'dates' which is solid state.

Got into amp servicing, at least mine, cause Miami is a waste land for amp servicing. No one no where..

Learned a lot about specific theory, but running about 30% in fixing my stuff. I still don't get the total picture of how the amps operate. Should get off my ass and learn ohms law. And how to really use it!

yep. im in the same boat. i dont gig though. but was pretty much forced due to finacial constraints to learn how to fix my own shit, or at least try.

what frustrates me is, the info is out there to find, if you dig enough....but if you ask someone, most aren't willing to help beyond "dont go poking your nose in there or you'll die".

last time i heard of someone dying during servicing an amp was.....


oh yeah. i never have.
not saying it doesn't or cant happen.
just saying, OK ENOUGH ALREADY! WE ALL GET IT. THERES A RISK INVOLVED, AND MOST OF YOU ARE SCARED OF GIVING ADVICE DUE TO LIABILITY.

but fuck, could you help a brother out if they ask after giving some background!!!.....even IF there's a slight 1% chance that they'll take business off of you....holy f..whats the point of living life if you're not willing to help someone. i've asked people here for in depth advice, and basic, topical advice and gotten either no response, or the stonewall GFY response.

that being said, i asked Mike Fortin a very specific tonal question, and, while he didn't answer it or break it down for me one bit and he even told me why, he DID point me in the right direction, and gave me the places to dig in to get what i needed. i had made up my mind years ago to buy one of his proprietary amps (namely the bones) or a heavily modded marshall rebuild (like a cali+ or bogner overhaul), and, the fact that he took time a week or so, right before NAMM this year, and REALLY truly gave me some great advice and direction is something i'm eternally thankful for. i learned more in the past 3 weeks or so than i have in the last year. thinking on it now, he gave me exactly what i needed (give a man a fish, feed him for a day......teach a man to fish.....etc).

anyways, yeah, i STILL dont get HOW amp circuits do what they do exactly, but im getting there. and i have a basic understanding of tonestacks, RC circuits, hi and low pass filtering, cathode and plate resistance and its effect, and some other stuff mostly preamp tweaking related.

the only thing i've done to my 5150 power circuit related was install the bias mod based off the PDF file that's floating around the net....and i modded it so each power tube can be monitored for it's own bias MA, but i still haven't figured out how to bias each tube, or each tube set....theres VERY little on the net about that.

anyways, sorry for the long book! LOL!

 

[daviedog]

Neg voltage at the grid is not your bias. Correct bias is the amount of current that the tube is drawing. If it is close to correct, neg voltage will appear at the grid. Since internal resistances of tubes may vary, the grid voltage will vary grid voltage may also vary.

A change of 1 volt at the grid could result in a change of 10ma of current, which way? Can't tell.

Tap from p/t 70 or so volts and reversed half wave rectifier to give neg current/voltage.

Cathode bias has no bias supply. Bias is derived from a resister in the cathode circuit of output tube. A lot less expensive to design and amps exhibit a nice sustaining quality. Cathode bias does not mean class A.

Got this a few months ago RCA data books.1930's on the web.

Was this your ?? For actual res values you could use a 'sub box' or install a socket.

Wouldn't it be cool if they just made consistent tubes & we wouldn't have to bother? You know, just drop and bop..

 

[Anonymous]

you know a lot more about that than i! thanks for the info....can you point me in the right direction for that RCA source material...id like to get my hands on that.

im doing my bias like this, which requires some traces to be cut on the power tube board, but so far, it's working fine, once i get all my parts, it'll be permanent, and not as jury rigged as i have it for the time being on the bench....i'd just like to figure out how to bias each tube. right now, i have it set so my bias knob increases or decreases as needed to get all the tubes within 60% operating range in relation to the amps plate voltage.

 

[daviedog]

Any bias measurements are difficult/labor intensive without a trimpot. To adjust bias supply to service tube. Look back to subbox last post.

If you don't have external bias points (5150?) you can acquire 2 for about 18 bucks. Some assembly required. Took me less than an hour. Go to Hoffman amps. They fit between tube & output socket (octal). Nice & neat.

I feel I have to invest in electrons. Not just tube amps to get it. Like music,
not just learning one song.
RCA Receiving Tube Manual is very helpful in aquiring an understanding. 262 pgs PDF so may download for free.
Tom Mitchell's Tube Amps for the curious musician. A real cool book that is amp specific.
Your trouble shooting skills much better than mine. This might be all you need..

 

[Sixtycycle]

UPDATE:
So the intermittent issue of OD 1 and OD 2 not working but Vintage 1 and Vintage 2 working fine described above.....

I found that when this happens if I unplug the input cable and plug it right back in with a little extra force it would sometimes kick the OD channels back in. Finding this extremely odd I checked all my cables and all were good. So lastnight during a gig of course my lemonater did it again and the unpluging pluging in the input cable trick did nothing.

So since I have the Effect loop engaged at all times with my volume pedal there for leads, I reached and unplugged and reinserted the send with a little extra force and waalaa!! OD channels back on. So whats your thoughts on the new issue on this POS boat anchor?????

If I don't get it tracked down quick, I think shes gonna have to go to service and then anybody who wants a hell of deal ON THIS ROTTEN EGGMASTER...IT WILL BE FOR SALE, I AM DONE, can't rely or take it anymore!!

Jeez this thing is worse at costing me more headaches and money than my Harley, my boat and my drag car all together.
Thanks for any thoughts or advise you all may have

 

[Anonymous]

obviously, it's something intermittent inside the amp.

could be a cold solder joint, or a loose wire...too many variables to troubleshoot over the net, and at this point, you've had too many different issues with it.

time to take it to an amp guy my friend.

 

[daviedog]

Are the jacks board mounted? Does this happen at operating temp(hot)only? What about pitch ? Only low( heavy vibration)?

With hi volume production. Many compromises made. Wave soldering, board mounted components,and thin boards all lead to early failure. It's a trade off between cool features & reliability.

Measure thickness of circuit board, not 3.5 mm. Could be binding. The jam it in fix you mentioned..

I like Yetis pick. Hundreds of welds & one stops the show
It's chop stick time. If you don't know what I mean, take to the tech. And if you don't have a thick glass board it might not be worth it.
A Thin PCB modern amp will not run reliably after 2 to 3 years in most cases. Wave solders and movement to lead free solder are huge contributors to this sad condition.
Great reading at NASA site on life/death soldering if you're into that sort of thing.

Good luck & may the great solos be yours!!

 

[Anonymous]

A Thin PCB modern amp will not run reliably after 2 to 3 years in most cases. Wave solders and movement to lead free solder are huge contributors to this sad condition.
Great reading at NASA site on life/death soldering if you're into that sort of thing.

Good luck & may the great solos be yours!!

that's not entirely true, well, it hasn't been my experience.

peavey 5150 has a flimsy preamp board, and rarely is the issue with those amps there

chop stick time !

i wouldn't overthink anything though in terms of what it can be. open the amp, drain the DC (if you dont know how, dont fuck around in there) cause these amps still hold DC in certain areas (reverb), regardless of what you may have heard. start going down the checklist. first id start with checking all the preamp sockets, wire connectors, and easy to access jacks and anything else that might work loose or cause intermittent sound.

if you find something, even one thing, plug the amp back in and play it. you can play it open. you just cant put your hands in there while its live. if it didnt fix it...turn off, unplug, drain caps, repeat. look for burn marks. check all your fuses. make sure all the wires coming from the PT and OT are connected solidly to the board.

without diagnosing, or even know what you fixed, you might get lucky and find a loose or intermittent wire...which is what i think it is.


some points of advice bro!...you gotta stop downtalking egnater dude....its making you look....inarticulate and somewhat childish.
most of us here know there were some Q&A problems for whatever reasons. Bruce/Nate etc have always been helpful here and over the phone to just about everyone that has posted. i understand your frustration. i went through my own frustration, but you gotta be willing to work through it, take it to a GOOD tech, or just take the fuckin thing to guitar center as is, and hope for a trade in, or sell it outright, "as is" and recoup some bux and move on.