Mark III died again - UPDATE 25/1/17 -

Mark I's, II's, III's and the almight IV

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kc_ksom
Mark II
Posts: 70
Joined: Tue Nov 29, 2011 2:52 am

Mark III died again - UPDATE 25/1/17 -

Post by kc_ksom » Sun Apr 03, 2016 5:33 pm

So my Mark III blue stripe died again over the weekend, reliability has been pretty bad with my amp this is now the 3rd time its broken down, this time similar as the last, had some major crackles and static noise then nothing, and the smell of burnt electrical's - but all tubes seem to be glowing.

I really like the sound of the amp, when its going it sounds unreal but I think I might piss it off and get a fender or Ceriatone JM - SSS or something along them lines. Anyone else have reliability issues with theirs ??

Casey
Last edited by kc_ksom on Tue Jan 24, 2017 6:28 pm, edited 1 time in total.

Promethean
Mark II
Posts: 81
Joined: Wed Nov 13, 2013 7:53 am

Re: Mark III died again

Post by Promethean » Mon Apr 04, 2016 2:53 am

Other than a bad valve a couple of times, my purple stripe has been super reliable for nearly 30 years over hundreds of gigs and near daily studio use. I am considering a cap job but only because of its age rather than noise problems. The valve problem was also only when I used power valves that were not Mesa tested but claimed by sellers to be compatible.

Has it any mods by previous owners, has it been properly cleaned, checked and overhauled by an amp tech? New set of correct value tubes?

kc_ksom
Mark II
Posts: 70
Joined: Tue Nov 29, 2011 2:52 am

Re: Mark III died again

Post by kc_ksom » Mon Apr 04, 2016 6:30 pm

Yea mate - its been modified to use EL34 valves - yes its been to a recommended repairer here in Brisbane by the name of BJ Amps - he is recommended by Pro Audio (the importer) - he has serviced - cleaned - replaced screen grid resistors, valves - some resistor on the board that fried last time (you can view that in one of my posts if you look at an earlier post) and a few other things I just cant remember right now.

I did contact Mesa Boogie about the problems it has - they sent Pro Audio a message to contact me (Which they did) but the only thing that they would do was to completely overhaul the amp components and bring it back to the way it left the factory - the thing is I like the way it sounds now and I don't want to change that - I just want the crackle & pop to stop on start up - its always made this noise - so until that issue is fixed I don't think it will ever be OK or reliable, end of the day I may as well put the money towards a Mark V or a Jp2c >?

casey

Promethean
Mark II
Posts: 81
Joined: Wed Nov 13, 2013 7:53 am

Re: Mark III died again

Post by Promethean » Tue Apr 05, 2016 2:51 am

Shame. Maybe just got a bad one. Bad luck. I love my Mark 3 but if I ever had to replace it I'd be looking at Boogie again... Mark IV or V, RoadKing or a Lonestar

tommyhawk13
Mark III
Posts: 227
Joined: Fri Jun 09, 2006 11:31 am
Location: Jacksonville, FL

Re: Mark III died again

Post by tommyhawk13 » Tue Apr 05, 2016 9:07 am

Do you play through the amp regularly, or just every now and then?

A similar thing happened to me a long time ago.
I used to only play my .50 Caliber a few times a month, and I'd crank it up when I did. It would crackle and hiss, and after a bout 20 minutes, the volume would drop (to almost nothing), and it would sound fuzzy, even on the clean channel.

A tech told me to spray it down with TV tuner spray. It made the amp sound like new again.

He said my playing habits were at fault. Crud was building up around the contacts, and if I played more often, it would burn it off, or some such voodoo.

Try De-oxit, and remove the tubes and spray down in the contacts. It's worth a shot before you take it to a tech again.

Good luck!
1987 .50 Caliber, no eq
Quad preamp
50/50 Stereo power amp
4X12 Half back 280w MC90's/Eminence vintage 50's
4X12 Half back 460w MC90's/EV's

kc_ksom
Mark II
Posts: 70
Joined: Tue Nov 29, 2011 2:52 am

Re: Mark III died again

Post by kc_ksom » Tue Apr 05, 2016 11:20 pm

Hi Mate

Yea I play it fairly regular, 2-3 times a week, sometimes more (depends on the Mrs - lol) - but it crackles and hisses and mucks around every time I turn it on, just this time it went bang and fried.

I also have a dual recto - but I just cant get that to sound as good for what I play, its a different animal to the Mark III, I think I like the Mark series a lot more, but on the other hand the Mark series cant sound like a recto - so yea I keep it around, but thinking of moving it on aswell.

I'm now contemplating getting a SSS from Ceriatone, its Dumble clone of the Steel String Slinger or a Two Rock, very John Mayerish which is what I have been noodling around with these days - you know that live concert - Where the light is - that Strat and amp combination just sound to my ears a very nice mix, I just wished I had Johns chops and musical arrangement.

Casey

McBarry
Donating Member
Posts: 383
Joined: Thu Jul 09, 2009 1:41 am
Location: Canberra, Australia

Re: Mark III died again

Post by McBarry » Sat Apr 23, 2016 8:09 am

Casey,

immediately I'm thinking same thing as tommyhawke13.
Crud on the board, causing micro-shorts between tracks - usually HV and signal tracks.
Plenty other possibles, but that's my initial expect..

Has it been tried since the big crackle and smell issue ??

If U wanna pull the chassis and bubble/box it to Canberra I'm happy to look at it for U..

PM and we can sort it..

Dave
Mk I,export,GEQ,cream
Mk IIA,exp,rev,cream
Mk IIB,exp,rev, tweed
Mk IIB,exp, rev,GEQ,simul, black
Mk III head,rev,GEQ,cream
Mesa Studio 22+, fan
Kitty Hawk M1 head
Fender 75, exp, 1973,15".
Fender 6G6A Bandmaster 1962
Fender AA763 Bandmaster 1964

mark2boogie
Mark III
Posts: 268
Joined: Thu Jun 02, 2011 4:00 pm
Location: France

Re: Mark III died again

Post by mark2boogie » Sat Apr 23, 2016 1:43 pm

Yes, Casey.

I am akeen to think like Dave (McBarry) and tommyhawke13 too : a complete cleaning of the amp circuit would be a good thing to do, if you can perform it (it's a long, delicate and accurate job, something like a paleontologist work, nothing to do with just spraying a product here and there or worse: everywhere :x ...). Moreover, doing that, it would help you to detect an hidden / unsuspected default.

A+!
Only one venerable Boogie MKIIA S/N° 4915 from March 1980 (dixit Daniel "igfraso" - thanks !), in Tolex Cab with a 1978 ALTEC 417-8H Series II speaker, and personal circuit improvements.

guilhemamplification.jimdo.com

kc_ksom
Mark II
Posts: 70
Joined: Tue Nov 29, 2011 2:52 am

Re: Mark III died again

Post by kc_ksom » Wed May 18, 2016 6:00 am

Had a little play around with diagnostics tonight - I pulled the power tubes out and put them in my dual rectifier and the power valves are fine - I searched for loose connections, couldn't find anything- I searched for scorching or burnt things - couldn't find anything- I done a tube roll - still found nothing - I plugged my guitar into the fx return and I had a nice tone but all the front dials don't do anything as they are on the pre amp before the fx circuit - so something to do with the input pre amp side of things -

There is some noise of my playing through the input but it is very low output - but there is white noise that is constant- it still crackles a little when the standby switch is turned on, we checked filter caps but only with a multi meter so not accurate but they seem to build capacity- I don't have any other way to check it - does any of this sound like they know what might be causing the problem??
Casey

BigBadWolf
Mark I
Posts: 33
Joined: Sun Dec 20, 2015 5:47 pm

Re: Mark III died again

Post by BigBadWolf » Tue May 24, 2016 7:18 am

I know several cases, where effects loop causes that kinda behavior.

Disconnect everything but your speaker cable. Plug your (100% fit) guitar cable in input. Test. Switch all channels by using push pull pots. Make sure it is not about channels.

"Wake up" loop jacks by using a plug in a manner that would make you look very odd if someone looked (put in, pull out gently but firmly several times as long you can be sure that possible dirt on contacts has gone). If no help, try to use short cable in loop just to test/make sure the problem is/is not in your loop.
Mark III red stripe simul class, Mark V combo (with old half back) and Mark V head with three quarter cab.
Played with few PRS's.
No. I don't match with my gear as a guitarist. How could I? I have the best gear there is.

kc_ksom
Mark II
Posts: 70
Joined: Tue Nov 29, 2011 2:52 am

Re: Mark III died again

Post by kc_ksom » Tue May 24, 2016 7:31 pm

I will try the short cable in the loop, but I think it has something to do with the signal path in the preamp as the amp is doing everything that its suppose to do, its switching, loop works, I can hear the gain volume working, I can hear all the push pull pots working etc, the only thing is its not amplifying the sound to the power side of the amp, but all the functions are working, it beats me

casey

McBarry
Donating Member
Posts: 383
Joined: Thu Jul 09, 2009 1:41 am
Location: Canberra, Australia

Re: Mark III died again

Post by McBarry » Tue Jul 05, 2016 2:17 am

Hi Casey, did U get the MkIII sorted ?
Hope so...
Mk I,export,GEQ,cream
Mk IIA,exp,rev,cream
Mk IIB,exp,rev, tweed
Mk IIB,exp, rev,GEQ,simul, black
Mk III head,rev,GEQ,cream
Mesa Studio 22+, fan
Kitty Hawk M1 head
Fender 75, exp, 1973,15".
Fender 6G6A Bandmaster 1962
Fender AA763 Bandmaster 1964

kc_ksom
Mark II
Posts: 70
Joined: Tue Nov 29, 2011 2:52 am

Re: Mark III died again

Post by kc_ksom » Tue Jul 05, 2016 11:19 pm

G'day Dave


Mate - I haven't - the old man looked at it but he couldn't find anything visually wrong - so I wanted someone in the know to do it. I spoke to the Tech at Pro Audio who was pretty helpful, but he reckons if he does anything he will replace everything 1st (overhaul it). So that's as far as its gone.

Failing all that I was just going to take it back to B J Amps as he is local for me and pretty easy to deal with.

But now I'm thinking of buying a Mark IV instead

Are you interested in the mark III still as it is ???

Casey

kc_ksom
Mark II
Posts: 70
Joined: Tue Nov 29, 2011 2:52 am

Re: Mark III died again

Post by kc_ksom » Tue Jul 05, 2016 11:25 pm

I should have said, I have just been using it as a power amp through the effects loop, everything is working in that respect, the EQ works and master volume - but no reverb or presence control. or any of the front knobs.

When I do plug into the front of the amp input - I can hear what im playing etc. But its not amplified - its not very loud - so it has to be the input circuit to the power amp.

casey

kc_ksom
Mark II
Posts: 70
Joined: Tue Nov 29, 2011 2:52 am

Re: Mark III died again

Post by kc_ksom » Tue Jul 05, 2016 11:38 pm

When I powered it up after dad done some testing and, I could smell something hot - I seen a little smoke for a short time - but no smoke since then.

I checked all tubes out of the Mark III in my dual rectifier, and all sounded fine - I also done a tube roll as well with no change - so I don't think its tube related, and I don't reckon it would cost much to fix as there really is nothing visually wrong, so maybe dirt - cracked track or trace wire, failing components in the input circuit - yea. but anyway - its tech time either way

casey

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