JCM800 Goes Boom:

Inspector #20

Inspector #20

Ambassador of Tone
Fallen Star
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Some shots of the #2203 from Rat's Nest Studios. Just received a $900.00 'tune-up' from the builder last year.

Rat's Nest Studio.jpg

The JCM on the floor in the control room. It runs to a 600 pound isolation cabinet on casters in the next room.

Amp 1.jpg

First look inside...knobs on left and microswitch are labeled for the FX loop. Tag under the left power tube socket reads "100 Watt Conversion by Mike Morin."

Morin Phone Redacted.jpg

I redacted his phone number. Serial indicates a 1983 50 watt #2203. Carved into the steel chassis is a statement that reads it is now a 100 watt with an FX loop.

Board.jpg

Note sanding on orange caps to remove markings. Far left cap is sanded through to Mylar (on bottom) from what appears to be an errant swipe with a Dremel while shortening the leads.

Some of the ground braids are soldered to ground and some were never connected to ground. The black paint on the resistors is conductive paint

Top Soldering.jpg

Note the soldering performed without removing the board. Several of these joints were cracked. The entire chassis was full of slag from the soldering process and silica from sandpaper.

More to follow....
 
Robert Herndon said:
Some shots of the #2203 from Rat's Nest Studios. Just received a $900.00 'tune-up' from the builder last year.

View attachment 46260

The JCM on the floor in the control room. It runs to a 600 pound isolation cabinet on casters in the next room.

View attachment 46258

First look inside...knobs on left and microswitch are labeled for the FX loop. Tag under the left power tube socket reads "100 Watt Conversion by Mike Morin."

View attachment 46259

I redacted his phone number. Serial indicates a 1983 50 watt #2203. Carved into the steel chassis is a statement that reads it is now a 100 watt with an FX loop.

View attachment 46261

Note sanding on orange caps to remove markings. Far left cap is sanded through to Mylar (on bottom) from what appears to be an errant swipe with a Dremel while shortening the leads.

Some of the ground braids are soldered to ground and some were never connected to ground. The black paint on the resistors is conductive paint

View attachment 46262

Note the soldering performed without removing the board. Several of these joints were cracked. The entire chassis was full of slag from the soldering process and silica from sandpaper.

More to follow....
Click to expand...
I don't understand.
Are you saying that you paid this guy $900? to modify the amp?
Or are you saying that it was already done when you bought it?
Well looking at it, I'm not surprised it failed....
So if you need any help.
It's a real slop job that's for sure. A real life hack.

It's not the first destroyed Morin amp I've seen either. There's others.

What usually happens when goofy tried to solder the top of the board is that the circuit tracks are all torn up.
So to really fix it right the board needs to be removed and re-worked.
 
Amp Mad Scientist said:
I don't understand.
Are you saying that you paid this guy $900? to modify the amp?
Or are you saying that it was already done when you bought it?
Well looking at it, I'm not surprised it failed....
So if you need any help.
It's a real slop job that's for sure. A real life hack.

It's not the first destroyed Morin amp I've seen either. There's others.

What usually happens when goofy tried to solder the top of the board is that the circuit tracks are all torn up.
So to really fix it right the board needs to be removed and re-worked.
Click to expand...

The amp is owned by a local studio. It was purchased from the builder already modified "a few years ago" for around $2,000 I am told. Last year, they had trouble with the amp. They do not even attempt to change tubes. The amp went back to the builder for repair and received new tubes as part of a "tune-up" - in October or November - for which they were charged $900.00. I do not know just exactly what else was done, but will post more data when it becomes available.

I found a nearly identical twin to this one on Reverb:

Marshall JCM800 2203 100 watt 1982 Modified by Mike Morin | Raritan Bay Guitar Repair | Reverb

Some of these amps on Reverb may have been molested, post-modification. But we know that this one - from what I am told - has a verified history with the modifier/builder.

The funny, if not ironic thing that I see, is nothing that is done inside this amp is innovative. It's all copies of circuit mods that you can find on any You Tube channel. To go to the trouble to sand the numbers off a cap or to paint (read: insulate) a resistor with conductive paint, is not hiding anything. There is nothing "trick" here. Just a lot of bullshit.

To intentionally put unshielded grounds inside an amp in the vicinity of a transformer and storage capacitors shows just how little the modifier really knows about amplifiers. But this is not the first time I have seen this from a builder of equipment that has developed a following.

There are many 'builders/modifiers" who will do a cracker-jack job on a celeb amp, and then do poop work on everyone else's.
 
ivan H said:
Wow, I'm speachless. A $900 tune up you say,,, I wonder what a "budget" tune up looks like. Cheers
Click to expand...

I know a Los Angeles artist that bought a Dumble Overdrive Special from the man himself. A much anticipated purchase. He was asked to sign a contract that stated he would not allow anyone else to service it or even look inside it. The amp stopped abruptly on him, so I offered to help him on the down low, just to get him back up and running. I was shocked at the sloppy soldering work that I found inside. There was absolutely nothing "trick" or "proprietary" inside that amp. The quality of work was certainly not in alignment with the prices charged.

But, TBTH, this really is commonplace in our world.

Of course, there will always be that hamburger that is on the front of the menu, but it looks nothing like the hamburger you receive.

But the hype and bull:poo: is a money maker for some...

Dumble Security Agreement.jpg
 
You know, this really got me to thinking. There is a strange mindset at work with music equipment in general, and not just with the end user, but also with the manufacturers. Some equipment - like the 1959 Les Paul - is somehow elevated to some kind of God-like status, when, in reality, they are not nearly as great as all the hype when you actually get your hands on one.

When I tried my hand at putting together custom guitars, I got so many hateful and downright discouraging emails regarding things that I would post. Everything from criticizing the aesthetics of my patented head-stock design, to mixing attributes of Fender & Gibson into one instrument. But on each and every one of the 27 guitars that I produced, each and every one of them received consistently good work.

I would be happy for anyone to open one of my builds and post photos of the internals. I would never send one out the door that I couldn't be proud of. But, maybe when the workload becomes too great, the work quality suffers???

I got to a point where I realized that people like tradition, even if there is something better or something with greater attention to detail. I just totally stopped after that realization, but I feel good about the one's that I produced...

Two Stagecrafters.jpg

The one on the left belongs to Marty Stuart:

Number 14 Headstock (1).jpg

Ugly, but original headstock design:

Von Herndon Number 1 (1).jpg

My first custom build. 24.75" scale, fat '58 Les Paul profile neck with a Floyd Rose. I sank the bridge posts in the wrong place and could never get the intonation right:

Von Herndon Headstock Prototype #1.jpg

This is on permanent display in Mom's studio:
 
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Robert Herndon said:
I was asked to prepare a repair estimste, and perform the repairs, if approved, so as to make the amp sellable.
Click to expand...

Well I listened to one of these Morin amps on You Tube last night.
I wasn't particularly impressed...
I think IMHO that a properly working 2203 sounds a lot better than the modified version.

Shielded wires:
The shield does not necessarily need to be connected to ground in all cases.
The shield can still work without being connected to ground.
Connecting the shield to ground may kill too much high frequencies.
I have tried this many times, and both ways...

It would be good if you took a whole bunch of pictures and documented the entire circuit. This may help others.
But I would expect to find that underneath the board, the circuit tracks are damaged.
Of course you still have that extra tube socket hole in the chassis. And, maybe an extra hole in the face-plate as well...then you have extra holes for the effects loop jacks.

I can show you guys:
just 1-2 parts and you can make this amp take off like a rocket. That's the funny part.
The metro effects loop kit is a much more professional approach, if you want a loop.
Unfortunately, the spacing of the effects loop jacks probably don't match an effects loop board which can be purchased.

The Dumble uses an FET gain stage.
But I have never seen anybody make a "Dumble Clone" that really sounds like a Dumble.
The clones I have seen are basically a joke.
Although, there are several who sell "Dumble Clones," using Dumble's name to promote their own product....but there is a surprising number of people who fall for it.

They think that they are going to sound like John Mayor.
Of course it doesn't sound anything like John Mayor, it's just a bunch of BS.
It sounds like a Fender Princeton.
But still people are dumb enough to believe the hype.
 
Robert Herndon said:
I know a Los Angeles artist that bought a Dumble Overdrive Special from the man himself. A much anticipated purchase. He was asked to sign a contract that stated he would not allow anyone else to service it or even look inside it. The amp stopped abruptly on him, so I offered to help him on the down low, just to get him back up and running. I was shocked at the sloppy soldering work that I found inside. There was absolutely nothing "trick" or "proprietary" inside that amp. The quality of work was certainly not in alignment with the prices charged.

But, TBTH, this really is commonplace in our world.

Of course, there will always be that hamburger that is on the front of the menu, but it looks nothing like the hamburger you receive.

But the hype and bull:poo: is a money maker for some...

View attachment 46271
Click to expand...

Silly and unenforceable "contract" so people don't realize he's using parts that he pulled out of broken coffee makers. Same with the stupid goo he dumps on everything.

I've played through two different ODS' - one was a 1x12 combo and the other was a head with separate 1x12 cab. To say I was underwhelmed would be a disservice to things that I find truly disappointing, since there is no way to play through a Dumble and not factor in the price and the ridiculous hype surrounding them so I need to find a stronger word for just how "meh" the things were. There were, literally, dozens of other amps in the shop that ate their lunch for a fraction of the cost.

I've even noticed with recordings and videos of them that they just sound really, really average even when used by guys that can certainly play circles around me (looking at you Larry Carlton but there are others, and in the relatively recent Bonamassa rig rundown the two Dumbles just sound BAD and IMO are actually mucking up the great tone he's getting from the high-power Twins).
 
gball said:
Silly and unenforceable "contract" so people don't realize he's using parts that he pulled out of broken coffee makers. Same with the stupid goo he dumps on everything.

I've played through two different ODS' - one was a 1x12 combo and the other was a head with separate 1x12 cab. To say I was underwhelmed would be a disservice to things that I find truly disappointing, since there is no way to play through a Dumble and not factor in the price and the ridiculous hype surrounding them so I need to find a stronger word for just how "meh" the things were. There were, literally, dozens of other amps in the shop that ate their lunch for a fraction of the cost.

I've even noticed with recordings and videos of them that they just sound really, really average even when used by guys that can certainly play circles around me (looking at you Larry Carlton but there are others, and in the relatively recent Bonamassa rig rundown the two Dumbles just sound BAD and IMO are actually mucking up the great tone he's getting from the high-power Twins).
Click to expand...

JoeB does have a very nice timbre to his tone!!!!
 
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