M400 #1037
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Mellotron M400 #1037

M400 #1037 is now running!


Ken Leonard fixing Mellotron M400 #1037

M400 #1037's auction picture.  Why are the keys uneven?  The mouse droppings had found their way in between the keys and lodged there.

From Toronto's busy streets to Jerry Korb's quiet garage in Vermont

M400 #1037 was the one offered for sale on EBay in September 2003 that had been invaded by mice.  The original auction is reproduced here in all its gory detail.

I assure you:  the auction description was spot on.  That may have been why it did not get a single bid.

Known issues included the usual missing on-off switch cap and pitch control knob.  The unit had not been used in ten years, and the owner told me that the last time he tried it, the motor went "Whoosh!" when he turned it on.  But that's all he knew.

What you see is what you get.  It is what it is.  As-is, where-is.  Caveat emptor.  Despite the unknown condition of this beastie, I made an offer to the owner, and a deal was made.

I've been working at a software startup since January '02, and I haven't had much of a breather in all that time.  What I wanted was a neat/fun project (fixing up an M400 could be that), but more than that I really needed to get away from work for a few days.  So I planned to make it a "driving vacation" from Boston to Toronto, then back to see Professor and Mrs. Korb in the delightful woods of Vermont.  Though the drive would be 650 or so miles each way and would be Boston to Toronto on Friday, Vermont on Sunday, Boston by Tuesday, I knew it was the right prescription for me at the time to chill out a bit from work.  AND IT WAS!

M400 #1037...running!  Welllll...kinda...

But that wasn't the only reason for the drive.  Having met some awesome people in Toronto at the Mellotron Symposia, I had the pleasure of catching up with Rick and Vicki Blechta, Chris and Maxine Dale, and Clay Eccles during my visit.

The plan.  My plan was to drive to Toronto on Friday October 3, grab the 'tron from the seller on Saturday, store it overnight in the hotel, drive to Vermont on Sunday to work on it with the help of the Mellotron Professor Jerry Korb, and be back to work by Tuesday. 

I arrived in Toronto on Friday evening 10/3/03, and that's as far as the plan went.  The hotel was in a busy and noisy section of Toronto, and it didn't have parking (had to park in a garage two blocks over), nor was there any way to get the 'tron into the hotel room for safekeeping.  oops, no chance to change plans.

Enter Rick B.  Wow---he REALLY helped me out of a jam.  Rick offered to come by with his minivan and help me retrieve the 'tron and even store it overnight.  Now you see why I wanted to go to Toronto to catch up with these folks.

Aside from being ever so helpful, Rick is well known in Toronto's music circles, and he's a published author as well.  Not only that, he is behind may new Mellotron sounds!  Head on over to Rick's web site for more, including a special promotion for his book Shooting Straight in the Dark.

Saturday was cool and raw in Toronto, with the wind whipping off the lake and no sun to warm the air.  I walked outside the hotel to wait for Rick, and I tossed my jacket on more or less to just have it with me and didn't even zip it up.  Everyone I saw walking by was bundled up as if for a major snowstorm!  Big coats and parkas, big mittens, hats and earmuffs was the rule of the day.  Where many people don't where white or "spring-like" clothing after Labor Day, Torontoans and Torontites must give in straight away and go from heavy wool sweaters in August and move right into blizzard gear in September.  I prefer this weather, so I was perfectly happy.

Rick arrived, and our plan was to head to a pub near to where the person who was selling #1037 lived.  Toronto is putting in streetcars, so nearly every turn Rick tried led us to more construction, but, using skills he learned as a cab driver years ago, he was able to get us over to the pub where we met and had lunch with Chris, Maxine, and Clay.  Clay brought over some new tunes he was working on, and I reminded him--again--to finish Stravinsky's "Firebird".  So I thought I'd put that here to remind him...again.  :-)

I called the seller at our agreed upon 1pm.  He's a DJ, and he's often up late.  But the wild card was he could be called to work a whole Saturday, and this would have meant picking up the 'tron on the Sunday.  Fingers crossed, I dialed his number, and woke him up.  Sorry, Rod!  Well, it meant he was home, and he asked if I could give him some time to get ready.  No problem---we went back to our pints and an interesting Canadian Maritime blueberry cake dessert thing that Maxine said was popular where she grew up.

Eventually it was time to head for the 'tron.  Rick, Chris, Maxine, and I hopped into Rick's minivan and drove over to Rod B.'s house to see what the M400 advertised in that EBay auction was all about.


Rod led us down into his basement apartment on a very charming but quiet street near one of the busier sections of Toronto.  Sitting there among several musical instruments and piles of CDs was Mellotron M400 #1037.  It looked just like it did in the picture.

I removed the lid and noted the mouse crap.  Boy, was Rod ever right.  Although they were gone, the evidence was there in black goo over all the flat parts and urine stains on the wood of the keyboard.

I removed the keyboard (getting my hands covered in who-knows-what in the process) and inspected all the parts.  Everything was there, including the 2nd tape frame (with relatively new Kean tapes) that was part of the deal.  Sweet!

A few warning bells went off in my head...

bulletThe unit had not been used in several years, and the last time Rod used it he said it made a "Whoosh!".  The pitch pot was loose and seemed abused a bit.  Hmmmm...I'll come back to this later in my report.
bulletA mouse dropping had worked its way in between two keys an rusted onto the capstan.  This, if not repairable, would have been the death of the machine.  Fortunately because the dropping plopped between two keys, it was barely in the tape path, so I figured that it was probably not a mortal injury.  More later.
bulletThe tape set, seemingly cut on original stock, was knackered.  Two tapes were spliced, and all tapes were covered in a film, probably dander from the mice.  It's a shame, as they do play and sound great, but the goo on the tapes un-did some of the cleaning work, and some tapes were spliced anyway, so the tapes are going into the bin.  Sorry, folks.
bulletHunta virus.  OK, you chuckle, but let's face it.  Fortunately we're all still breathing, so we're safe.

Because everything was there---power cord, take-up box lid, motor, controller (CMC-10), tapes & extra frame, keyboard, all panels, etc---the deal was done.

Chris and I packed up #1037 into the Protect-O-Muff that #805 (my first Mellotron) cheerfully loaned for this purpose, and Chris and Rick trundled the 'tron out to the minivan while seller Rod and I sealed the deal.

Chris and Maxine left for a few hours, and Rick and I drove over to pick up Vicki.  They brought me by to see Vicki's studio where she teaches flute, and it is a quiet, comfortable place where I could envision her inspiring the next generation of flautists.  After dropping #1037 off at the Blechta residence, we spent the evening at a pub down the street from the Bow and Arrow, only because the B&A was crowded beyond belief (we're not the only ones who like that place).  It was nice to relax in a Firkin' pub for the evening.

On Sunday I left the hotel and drove by Rick's place early in the morning to pick up #1037, and we managed to get it into the back of my Integra (which some people don't believe, so I included a picture).  Off I went for the 7 or 8 hour journey to the back roads of Vermont, taking the main highway out of Toronto and the northern roads of New York.

You CAN take it with you
Snug in a Protect-O-Muff loaned to him from #805, #1037 endures the nearly 700 mile journey from Toronto to Vermont and then back to Boston---in the back of a '95 Acura Integra!

My trip back to the States was pleasant, as it was a quiet Sunday along the highway.  The worst part of it was only hearing the first four innings of the Red Sox playoff game, then losing all hope of a signal, and only hearing small bits an pieces 'til the end.  (The Sox wound up coming from behind in the series and beating the A's, only to lose in the next series to the Yankees in extra innings of the 7th game---damn!  The Marlins eventually nailed the Yankees in six, though, so that's OK.  Sorry, Fritz!  :-) )  I crossed back into the States at Cornwall, having about a 40 second wait at the border.  Then I drove east through northern New York heading toward Vermont.

I called Jerry while I was still somewhere in New York, about 45 minutes from crossing the big bridge into Vermont.  He told me that he and Mali were waiting for my arrival, and Mali (who's a great cook, by the way) had a nice home-cooked meal for me.  That was more than fine, and it was certainly appreciated after all the cholesterol I was packing away at the highway stops.  I arrived at the Korb Compound during the early evening, chowed down, and decided to leave #1037 'til the next day.

My plan was to work on #1037 on Monday, drive home on Tuesday and be back at work by Tuesday afternoon or Wednesday.  We started our work on Monday, and that's as far as the plan went.  Frank Samagaio's "Pindertron"---the ex-Pinder Mark II Jerry was to restore--was due at Jerry's house on Monday...uhhh, no Tuesday...errr...Wednesday?  Jerry and Mali were cool with my sticking around 'til it showed, and I figured I could help move it around (despite my bad shoulder).  That was fine with me.  Well, I wouldn't wind up back at work 'til Thursday.  And that, too, was fine with me.

Meantime, it was time to dig into #1037.

#1037's Pedigree
Given the serial number, I'm guessing that 1037 was produced in 1974.  However if the date on the tape frame is original, I'm off by a bit.  The tag indicates the customer name of M. Douglas and a date of October 19, 1976.

The older (original?) tapes are GC3 Brass, 3-Violins, and 8-voice choir.
The Dave Kean set included in the 2nd tape frame has the same selection.

1037 spent most of his active life in a Led Zeppelin tribute band in the Toronto, Ontario, Canada area.

The machine was picked up at some point by Rod B., a musician/DJ from Toronto, where it's been for the past decade.  Rod wanted to find someone who'd take care of #1037 so he could free up some room in his place---and spend a bit more time on his vintage 1936 Indian motorcycle restoration (suh-weet!). 

As of October 4, 2003, #1037 had a new home.

Evaluation and Repairs Begin

There are beautiful autumn days, and then there are beautiful autumn days at the Korb residence in the wilds of Vermont.  It was a good day to work on a mouse poop laden Mellotron.

This job sucks (by definition).
The CMC-10 sucks (by design).

Before any kind of inspection work could begin, it was time to break out the rubber gloves and the Hoover.

We dismantled poor 1037 and Hoovered up all the mice rice at each step.  We were also careful to clean off all the poo goo at each step with alcohol.

Even after spending a great deal of time trying to do away with that final mouse biscuit, we'd keep finding them.  I think those crafty little mousy devils purposely hid their droppings in whatever crevices they could find just to vex us.


A bit of capstan luck
One Evil Mouse Turd made its way between two keys and onto the capstan.  Result?  A rust spot.

For the capstan to work correctly, it must be nice and smooth without pits or rust in its finish.  A trashed capstan can spell death for a Mellotron and make this whole endeavor fruitless.

Professor Korb to the rescue.  The photo to the right is about halfway through the repair.  Jerry carefully sanded off the rust, taking as little as he could off the capstan itself.  Most of it was surface, and the resulting divot is very small.

Best of all because the turd fell between two keys, the damage to the capstan is also mostly between two tapes!  Later on when we had the machine running, there was no perceptible issue with the capstan for pulling tapes through.

I just shake my head these days at Jerry's handiwork, "astonished" being an overused but apt description of my reaction.  Between Julia, the M300 that was dropped from a forklift and brought back to health, and the stunning home-built JK-MK6, everything is mechanically, sonically, and cosmetically as good as Jerry can make it.

As I got rid of the remaining mouse pellets, Jerry polished up some of the metal on the inside, like the head block, with Wenol.  I cleaned the urine-stained keyboard with some alcohol and went nuts on a lot of the goo on the inside wood and the frame with Simple Green and more alcohol.

Jerry also had a spare 'tron knob to dedicate to the cause, and we put it onto the machine.  And then there was the coup de gras:  Hammerite paint for the power supply!

Jerry had some of that stuff in stock for when he built and restored Julia's innards, and he sanded down the top of 1037's power supply to get rid of the rust and gave it some new cosmetic life.  Very nice.

Cosmetic work is one thing, but it was time to give 1037 a complete physical.  What we knew...

bulletAll the parts were there, and now they were cleaned up
bulletThe original tapes had seen enough (although those in the spare frame were pretty new and looked usable)
bulletKeyboard and rollers seemed OK.  We were watching the little pads fall out from under the adjusting screws at an alarming rate, though---will have to be glued back on later.
bulletThe pitch pot was loose and the knob was long gone
bulletWe'd need to make a preemptive strike and replace the cable going from the head block to the preamp
bulletThe last time the machine was used (10 years ago perhaps) it made a "Whoosh!"

"Whoosh"!!??  Now it was our turn to find out what "Whoosh!" meant.


We plugged it in and turned it on.  The pilot lamp lit (!!), but...nothing.  A few seconds later (thanks to the CMC-10's delay) we got a motor just barely creeping along, and things sounded squeaky.  Last time I saw a motor turn like that it was a matter of a few seconds before Mike Rivers' Bodge-o-Tron power supply began letting out smoke at our Philly Symposium. 

Uh ohhh...

But, nope, fortunately we didn't let any smoke out of the power supply this time.  Instead we released some tension in the drive belt and tried again.

"Whoosh!"....then....creep.  Then "Whoosh!" again!  Then creep as the motor slowed down, then up in speed again.

OK, the CMC-10 was causing this to "Whoosh!" up and back down.  We adjusted that to no avail.  Jerry got one of his "known good" (well, as good as can be anyway) CMC-10s, and we tried that.  "Whoosh!"...creep..."Whoosh!"...creep...Hmmmm....

More troubleshooting needed.  That's OK, as Jerry and I are both engineers, and we like puzzles.  The difference between us is that he can usually fix stuff, where as I...uhhh...go to Jerry.

Just a Fluke?  Jerry at the bench again.

It was time for Jerry to approach the bench---the test bench, that is.  We started investigating the "Creeping Whoosh" affliction in 1037.


Jerry got out the schematics for the M400 power supply and checked all the voltages.  Spot on.


The tach head?  Didn't have the same resistance as a known, good tape head, so we replaced that.  Didn't work.


Ohmed out the motor's windings.  Now wait a second...3 Ohms?  Jerry's known good spare motor read 10...hmmmm...

On closer inspection of the motor, I spotted that the wires feeding into some of the windings were frayed, dare I say the insulation looked a bit melted?

Our immediate next step was to try Jerry's known good motor in the machine.  Despite 1037 having sat for 10 years and having a CMC-10, Jerry's donor motor spun right up and worked fine.  We had our smoking gun, or, rather, a smoked motor.

Damn.  This was almost the lowest thing on the list of about half a dozen that could go seriously wrong in a 'tron.  I was more worried about the power supply and preamp, both of which are fine in this unit, as these motors are generally darn good and last forever.  Not this one. 

We thought back to the squeaky noises we heard when we originally started the machine and how the pitch pot knob was missing and how the pot itself was loose.  Our theory is that the capstan bearings started to wear out in this machine, and at that point they tried to compensate by tightening the belt.  This put further stress on the motor, and it began to flake out.  The pitch pot abuse was the final attempt of someone trying to get the pitch to stabilize.  After that, 1037 was given over to the mice.

With Jerry's motor in the machine, it was time to crank it up to see if it played at all.

We made the unfortunate decision to put the grungy original tape set back into the machine, as it later had me cleaning stuff up again, but the tape set was adequate for basic testing.

Motor on, Mellotron plugged into headphones, volume up...

One horrific wobbly after another coming up!

Yep, the preamp was fine.  And, after some basic adjusting, the keyboard was coming along, but I couldn't get it 100%, probably due to the grungy tapes.  No matter, as a nice set of tapes and sorting the keyboard will be part of the final setup anyway.  The important thing is that with a new motor controller, motor, and capstan bearings (all of which are available), this will be a runner.  My order is in with Streetly.

Jerry took a few minutes to solder a resistor across the preamp outputs.  This will prevent the heads from becoming magnetized should the head block cable become disconnected and then reconnected without shorting the preamp outputs first.  Good piece of prevention there.  He also made me a new cable to run from the head block to the preamp, as he had the parts all in his private stock.  Do this in your machine, too, else you'll find yourself with Screeching Cable Rot---which could lead to wiped tapes!

It was a busy Monday, but it was time to call it quits.  We packed up 1037 for its trip home to Boston, grabbed a few brews, and went out to a great Mongolian restaurant where you pick the ingredients and they cook it up.  Very yummy!

Unfortunately the truckers screwed up the delivery of Frank's Mark II, so I had to spend an extra day in Vermont waiting for it.  Gee, too bad for me, have to hang out with the Korbs again surrounded by trees, mountains, and wooly bear caterpillars.  The Pindertron didn't arrive on Tuesday, either, so we decided to give it 'til Wednesday.  Awww shucks, another day.  But, unfortunately, it was time to head out, and I had to leave all the 'tronning and Vermonting and Torontoing behind and head back to Boston (by way of New Hampshire's fabulous Fanconia Notch, of course...if I had my hiking gear with me, I probably would've stopped there as well).

THANKS to Jerry Korb...and, of course, to Mali Korb...for their hospitality and help.

Now what?

1037 already looks a bit better, and it'll be right as rain when the new parts are installed.  What the punch list looks like:


Capstan bearings (available most anywhere) - NOT NEEDED


Motor controller (SMS-2, new pitch pot) - DONE


Motor (new model, includes new mounting plate and belt) - DONE


New tapes ("Dreary Set" on order:  Piano, Smooth Organ, Guitar---all "dreary" Mark II sounds, but when played on Jerry's Mark I Julia, they really came to life) - DONE


Adjustment (of basically everything) - ONGOING...:-)


Continued cleaning/spiffitizing (gee, really looking forward to cleaning the tape frame that was in the machine with the mice...bleccchhhh) - ONGOING


Refinishing next year in the warmer weather - UHHH...NEXT YEAR...:-)


Replacing some wonky pinch rollers - DONE

I'm thinking...a pastel with a seashell motif...

During our work, Jerry and I took some paint stripper to 1037, and we found 1-2 coats of white, then black with some kind of blue magic marker all over it, then the original white, finally the wood.

For cosmetics, in the springtime I'm going to strip it all down to see what wood is there.  If it's nice wood (and all one kind), I'll stain it, and probably create a machine similar to Jerry's original M400 (only with white instead of Chamberlin black, I think).  If it cannot be stained, the machine will probably be refinished in some kind of color that shows a great deal of original thought, like white with little black feets.

M400 #1037 & Owner...or is it the other way around with these things?

How is #805...?

Although #805 wanted to show his support by lending his Protect-O-Muff, 805 was somewhat uncomfortable with a baby brother in the house and did sulk for a little while when 1037 came home.  Right now #805 is a bit tough to play, so I polished the metal on his keyboard frame, and he seemed to like that.  I have explained to him that 1037 needs our help while he's sick, and 805 seemed to understand.  I have my fingers crossed that he'll come around and be jiggy with having a baby brother at home.

Meanwhile I'm using #805 as a workbench to fix a Realistic Concertmate MG-1.  Jeez, I hope that's not adding insult to injury...