Did a total over haul on my Mesa Mark III ( Purple Stripe )

  • Thread starter Thread starter griff10672
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Nice job, I had my Mark III half assed working for way too long before I finally addressed it. Those amps deserve to running at full capacity.

Hope you get to crank it up & enjoy it often!
 


Great job. I have world class tech's here but they won't work on Mesa's. If my MK III purple stripe were a head & not a combo i'd still have it.
 
40 years old this year .... it was time .... that and I have been meaning to fix the reverb on this thing forever .

Replaced all the electrolytics including all the tantalum caps even the ones in the EQ ... got rid of all the carbon comp resistors in the power section and replaced them with metal films ..

Had to replace the reverb tank as well as the transformer that drove it ...

Replaced some wiring that looked to crusty for my liking .... also replaced the 40 year old fan ....

Plugged it in finally about an hour ago ...... Man this friggin thing SMOKES !!!!

some before and after shots

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finished product

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everything that got replaced

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Is your name Mike by chance, and did you recently retire from a longtime corporate job? :unsure:

If so and if bored in retirement, my Quad will eventually need a spa treatment. :cool:
 
so any difference in tone for better or worse after replacing the carbon comps? Randall claims that he used certain parts in critical parts of the circuit because it sounded better....(ie carbon comps in the power section) i'm not sure if i buy that or not. Mark III's were like the last fairly easy mark series to work on. I did all this stuff to a simul satillite once, which is basically a mark III with a way stripped back pre amp.
Carbon comps? You're talking about resistors right? I don't think it matters one bit what they are made of, they have a very simple job, to resist and they do that simple job regardless of what they are made of. Caps on the other hand do matter a little bit IMO, but I could be wrong on that cause they have a simple job as well. I think the circuit itself determines the tone for the most part.
 
Carbon comps? You're talking about resistors right? I don't think it matters one bit what they are made of, they have a very simple job, to resist and they do that simple job regardless of what they are made of. Caps on the other hand do matter a little bit IMO, but I could be wrong on that cause they have a simple job as well. I think the circuit itself determines the tone for the most part.
https://www.aikenamps.com/index.php/resistor-types-does-it-matter
 
Yours looks very good considering its age. I have a IV myself. I don't ever plan to sell it.
 
Looks great Wayne......:2thumbsup:I hate working on PCB's. I can't imagine working on an old Mesa Boogie like that. Congrats, I'm sure it sounds like brand new now!
 
Stock it's not the greatest ..... but there's a simple mod that's mentioned in the thread from the Boogie Board I posted ... makes the reverb a lot better ....

Thanks !!

yeah ..... that fugger gets HOT !
how involved was the reverb tank/transformer/mod?
 
Carbon comps? You're talking about resistors right? I don't think it matters one bit what they are made of, they have a very simple job, to resist and they do that simple job regardless of what they are made of. Caps on the other hand do matter a little bit IMO, but I could be wrong on that cause they have a simple job as well. I think the circuit itself determines the tone for the most part.
If the amp's tone changed ... I didn't notice it ...

I only changed the Comps in the Power section ..... there was only one comp in the tone path actually ... I replaced it with a more accurate NOS Comp I had

The way I looked at it was changing my oil and basic tune up on a car ... and I used more modern and safer parts to do it ..

those Comps can catch fire when they go .... destroying more than just a resistor . So the peace of mind aspect goes along with it
that website sucked me in ..... I've been meaning to stop by there
how involved was the reverb tank/transformer/mod?
not bad at all ..... it's getting at where you need to get to that's involved ...... the mod is just a resistor basically .... the reverb tank and transformer on mine were totally shot ..... the reverb wasn't working when I bought it a few years ago from GC .... I only paid 1100 for it because the reverb didn't work ... cost me I think 80 bucks maybe a 100 for the new tank and transformer ... all the caps and resistors were like 150 I think ... those little Vishay Axial Tantalums are friggin expensive ....

let me see how much a round trip ticket is to the Islands is ... I'll swing by for a few hours this weekend and hook you up ! :thumbsup:
 
If the amp's tone changed ... I didn't notice it ...

I only changed the Comps in the Power section ..... there was only one comp in the tone path actually ... I replaced it with a more accurate NOS Comp I had

The way I looked at it was changing my oil and basic tune up on a car ... and I used more modern and safer parts to do it ..

those Comps can catch fire when they go .... destroying more than just a resistor . So the peace of mind aspect goes along with it

that website sucked me in ..... I've been meaning to stop by there

not bad at all ..... it's getting at where you need to get to that's involved ...... the mod is just a resistor basically .... the reverb tank and transformer on mine were totally shot ..... the reverb wasn't working when I bought it a few years ago from GC .... I only paid 1100 for it because the reverb didn't work ... cost me I think 80 bucks maybe a 100 for the new tank and transformer ... all the caps and resistors were like 150 I think ... those little Vishay Axial Tantalums are friggin expensive ....

let me see how much a round trip ticket is to the Islands is ... I'll swing by for a few hours this weekend and hook you up ! :thumbsup:
tease😁


but truthfully you may wanna bolt before this pending new perfect storm cold front of the century kicks in!
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