PROJECT M3 - How I Spent My Summer Vacation

[Rusty Mike]

Hi,

 

just got an M3, doing the lower manual mod with jumpers mean that 2 first octave will be the same? BTW you work really well.

 

 

The net effect is that the bass in the lower manual is extended, allowing you to do true LH bass on the M3. It folds back the 16' drawbar on the lowest octave, doubling the frequencies of the 8' drawbar. Gives a lot of bottom end.

 

WesG - I just saw your question from last year. When Paul sold me the capacitors, he custom made the filters you ask about, so I have no idea what they are aside from what you see in the pictures.

[ABECK]

Great thread. I'm in the middle of adding foldback (non-poor man's method). It is a TON of work. I'm going one frequency at a time, but I've just run into an issue where I must have put one of the key contacts in the wrong place, It's a bitch trying to backtrack and determine where I made my mistake. Also, My solder sucker has broken 2 of the terminals that connect the key contacts to the manual. Switching over to solder wick for this part.

[vortmaxx]

This is exactly what I'm looking for: I love this place.

 

I spent yesterday helping a friend acquire a "new" Hammond CV. As a token of his appreciation, he is giving me his M3 and she is a beauty.

 

1st order of business will be to install a 1/4" out. I live in a small apartment with neighbors, and will need to defeat the internal speaker to avoid disturbing the neighbors. From what I've been reading around the interwebs, it sounded like the Trek II OBL-2 is the easiest (cheapest) route, and this pretty much confirms it in my mind.

 

Thanks, Mike. You rock!!!

[hazerkeys]

Hi - great post on your M3 project - I also have an M3 that I am working on, as well as a nice Leslie 145 that I have refurbed - I already have a trek 2 pre-amp to interface 1/4 input to the leslie, so only need the OBl-2 - which I was going to order (see link below) - but see that it does not come with the speaker switch you made - is that necessary ?

 

http://www.b3guys.com/Trek+II+OBL-2+Line+Output+Box.html/product_id/74

 

[WesG]

You don't technically need to buy the Trek II box if you are handy with a soldering iron.

 

All you have to do is provide a load for the AO-29's output transformer (10W 8 ohm resistor) and drop the voltage down to a level where your input device will be happy. A simple voltage divider based around a 10K log pot would do the job, there are lots of fancier circuits on the internet.

 

Note that if you're using an M3 with a field coil speaker, you will want to leave the speaker physically in place because the field coil is used as an inductor in the first stage of the power supply ripple filter. Also, these M3s require a 5-pin speaker plug to be plugged in, because there is a jumper on it (pins 2 and 4 I think?) that completes the power supply circuit. If you pull the plug, the amp will not work.

 

By the way, the organ has a "soft volume" tablet. If you press this, it won't be loud enough to disturb your neighbours, unless the TV is also a problem.

 

Wes

[Rusty Mike]

Hi - great post on your M3 project - I also have an M3 that I am working on, as well as a nice Leslie 145 that I have refurbed - I already have a trek 2 pre-amp to interface 1/4 input to the leslie, so only need the OBl-2 - which I was going to order (see link below) - but see that it does not come with the speaker switch you made - is that necessary ?

 

http://www.b3guys.com/Trek+II+OBL-2+Line+Output+Box.html/product_id/74

 

I made the switch so I could use the line out with or without the internal speaker. The amp needs to see a load, so the resistor on the switch is a dummy load when the internal speaker is disengaged.

 

Rereading your message, I'm a little confused. Which model TrekII device outputs a 1/4" for a Leslie connection?

[WesG]

He has a Trek II preamp, which is like a Leslie Combo Preamp. After that, you don't need a Leslie kit, you just take a quarter inch out from the organ into the Trek II preamp.

 

Note that I prefer proper Leslie kits and halfmoon switches, myself!

 

Wes

[hazerkeys]

thanks all - I too would rather have the proper leslie kit and switches, but already too many toys, and since this is just an occasional studio project, figured I would used the trek II that is just sitting around - so I assume that with the OBL-2 installed , I can take that 1/4 into the trek which would then feed the Leslie .. only diff without the homemade switch is that the M3 internal speaker will be on at the same time as the leslie, which is cool too

[WesG]

Yep, I have been running my spinets in "ensemble" mode (internal speakers and Leslie simulatneously) for a while. I like it that way. And I *hate* having two halfmoons on the front rail.

 

I am just about finished an M3 where the Leslie kit is a knock-off of the 26-1 box including 27-1 interceptor plug, but wired for a 760. I didn't bother including the M/E/E switch and just wired everything in ensemble mode. The best part was I was able to take the two halfmoon switches and make one three-speed tremolo/chorale switches out of it, perfect for the 760. When I built my 26-1 box, used a female TRS jack and wired it up the same as a Nord plug which is also compatible with the Neo Ventilator. This way, if switch to using a Vent product (thinking about MVfO) I can just move the tremolo control plug over.

 

BTW I have another M3 which is wired with a 6-pin jack and the Leslie switch is a light switch mounted beside the percussion buttons. It works surprisingly well. You can get the 6-pin jack and mounting hardware from Rick at TonewheelGeneral.com for about $15-$20.

 

You can also cut holes in the percussion switch mounting plate of an M3 for the guts of a halfmoon switch. Aka Telecaster pickup selector switch (I think).

 

Wes

[Markyboard]

Came across this old thread this morning as I've been restoring an M3 I recently acquired.

 

So far I recapped the pre-amp with a refresh kit from Tonewheel General Hospital, installed a Leslie halfmoon switch and 6 pin connector, fixed a couple of clacky keys, cleaned up the percussion set and vibrato/pedal set of switches, totally disassembled and cleaned the drawbars, rewired the pedal sustain switch and fixed a couple of missing tones (loose filter wires on top of the generator) .

 

http://i1062.photobucket.com/albums/t490/Markyboard/IMG_4987_zpsqydwh47k.jpg

 

 

Same percussion switch module as in a B3/C3/A100

http://i1062.photobucket.com/albums/t490/Markyboard/IMG_5004_zpskpas6zzc.jpg

 

Removing the vibrato/pedal switch module

http://i1062.photobucket.com/albums/t490/Markyboard/IMG_5007_zps75aohefk.jpg

 

http://i1062.photobucket.com/albums/t490/Markyboard/IMG_5014_zpsrpt7ofe4.jpg

 

Drawbar module - pain in the ass to reassemble if you didn't know not to remove the non-screw post

http://i1062.photobucket.com/albums/t490/Markyboard/IMG_5021_zpsybvqal7y.jpg

 

You can see the black residue on the left most section compared to the cleaned up sections to the right

http://i1062.photobucket.com/albums/t490/Markyboard/IMG_5023_zpss3dc8v4n.jpg

http://i1062.photobucket.com/albums/t490/Markyboard/IMG_4996_zps0zzac2n9.jpg

 

http://i1062.photobucket.com/albums/t490/Markyboard/IMG_4998_zps9gbdjugr.jpg

 

 

I love this M3 - kind of feel sorry for it wanting to be like it's bigger brother. I'm about to do the foldback modifications to both manuals including effectively lowering the lower manual by an octave. Lots of really good info from Rusty Mike's thread here. This is a fun winter time project.

[Joe Muscara]

[Doerfler]

I love this M3 -

 

can't wait to play it.

[mate stubb]

I love this M3 - kind of feel sorry for it wanting to be like it's bigger brother.

 

[Markyboard]

I'm about to do the foldback modifications to both manuals including effectively lowering the lower manual by an octave. Lots of really good info from Rusty Mike's thread here. This is a fun winter time project.

 

Here are some pics of my adding foldback. Same as the OP (Rusty Mike) only I used multi-color wires to keep track of what goes where. The lower manual wasn't too bad - just extremely tedious as it involves extending 60 wires and then soldering the other end.Yup Mike was right- not fun on a bad back.

 

http://i1062.photobucket.com/albums/t490/Markyboard/IMG_5078_zpslgmgfkro.jpg

 

http://i1062.photobucket.com/albums/t490/Markyboard/IMG_5079_zpsphizrvgi.jpg

 

http://i1062.photobucket.com/albums/t490/Markyboard/IMG_5081_zpsusnb9ish.jpg

 

Before starting on the "poor man's" upper foldback I removed this after market preset contraption. It was interesting for a while but I never use preset drawbar settings and it was making a mess of the cabling.

http://i1062.photobucket.com/albums/t490/Markyboard/IMG_5113_zps1ux7u1u3.jpg

 

This preset box was soldered into the drawbars and matching transformers. Lot of work to remove this - good riddance.

http://i1062.photobucket.com/albums/t490/Markyboard/IMG_5086_zpsgtscbkay.jpg

 

Big hole now where this resided - for now.

http://i1062.photobucket.com/albums/t490/Markyboard/IMG_5111_zpstpgz67c0.jpg

 

Adding the "poor man's" upper manual foldback - most challenging solder job I've ever done. Tiny wires and this time my eyes could barely get close enough. Won't be doing this again- hopefully ever.

http://i1062.photobucket.com/albums/t490/Markyboard/IMG_5165_zpslahfibbl.jpg

http://i1062.photobucket.com/albums/t490/Markyboard/IMG_5146_zpssioskmp8.jpg

http://i1062.photobucket.com/albums/t490/Markyboard/IMG_5149_zpsncywwuu8.jpg

 

 

 

 

 

 

 

 

 

 

 

[Markyboard]

But wait, there's more. Somewhere along the way I damaged the very top key contact -Ugg! Either that or more likely it was already damaged and I made it worse by pulling up on the lever tab (DON"T DO THIS!!!). It caused a constant drone when any of its assigned drawbars are pulled out. Fortunately (Very) it was the top end key and with removing a bunch more stuff I was able to pull the keybed back far enough to turn it and gain access to the end block. If this were not the last key contact position there's no way I would be able to get to it.

http://i1062.photobucket.com/albums/t490/Markyboard/IMG_5158_zpsvoc0mspo.jpg

 

Removing the end block I discovered that most of the contacts for this key had shifted down one position. No idea how this could happen as I couldn't make it reoccur even pressing down all the way on the tab after the fix. But by pulling up on the tab it just further bent the very tips of those contacts so that they were now making contact with some of the bus bars permanently. With a pair of needle nose pliers I was able to relocate the contacts to their proper position and unbend them.

 

Here's that upper note contact after the fix.

http://i1062.photobucket.com/albums/t490/Markyboard/IMG_5159_zpsg97yz73z.jpg

 

Last thing was cleaning 50+ years of grime off the keys.

http://i1062.photobucket.com/albums/t490/Markyboard/IMG_5167_zpskrz4jakh.jpg

 

And....DONE!

http://i1062.photobucket.com/albums/t490/Markyboard/IMG_5169_zpsg43merqk.jpg

 

[Rusty Mike]

Wow. Beautiful.

 

Are you happy with the result?

 

What kind of amp are you using?

[Markyboard]

Wow. Beautiful.

 

Are you happy with the result?

 

What kind of amp are you using?

 

Hi Mike- Oh man am I happy with it thanks in large part to your post here . Having that extra "octave" in the bass makes all the difference and while the upper foldback is no B3 it's still a big improvement -especially with vibrato on or leslie on fast. I've got this connected into my two 147s when I'm not using my clone stuff.

 

I just played my B3 for the first time since I started this back in December and the B3 is quite a bit brighter and "larger" sounding. It's using 2 122s but I'm guessing it's the tone gen filter caps that make the difference. Still this little M3 kicks ass. It does still have a few sporadic vibrato issues and the very lowest note is a bit dirty - might need a bus bar shift - but not today.

 

 

I've got this connected into my two 147s when I'm not using my clone stuff.

[mate stubb]

Note for next time (yeah, you said there won't be a next time!)

 

The key contact can be pulled out from the back by squeezing the two ends together and releasing it. The next time you get a cypher because a contact got smashed down to the next layer, you can gently pull it out a half inch and reinsert it into the correct row.

[Markyboard]

Funny, that occurred to me when I looked at the picture I was posting. I believe Wes or you mentioned that in another post when discussing adding contacts for "real" foldback. I was wondering how you get to repairing contacts in the middle of the board. Anyway that's very helpful info and while I can't see re-doing the foldback I would now attempt to fix any key that gets thrown under the bus(bar).

 

Thanks again.

[Doerfler]

Wow. Beautiful.

 

Are you happy with the result?

 

What kind of amp are you using?

 

I was delighted to play this organ last week. Best looking, best sounding M3 I have ever played. I had hoped to hear it through it internal speaker (Green Onions) but it was disconnected.

With the foldback mod going through a pair of 147's it sounded like it's big brother to me.

(Mark says almost.)

[ABECK]

Looks great.

I did a similar M3 project. Added Foldback on both manuals, got rid of the percussion drop, lowered the bottom manual an octave and set the trigger point SUPER high.

It is very fun to play! But, it is kind of dark sounding. Been toying with the idea of re-capping the tone generator, but not ready to go there yet.

[Markyboard]

With the foldback mod going through a pair of 147's it sounded like it's big brother to me.

(Mark says almost.)

 

Well I may have said more like "not quite" . Like ABECK the M3 is darker/older sounding than my B3 and the bass notes are much more distinguished on the B3. Since the 147s on the M3 are supposedly brighter than the B3's 122s I'm sure it's all organ (almost) that makes the difference. However I have no desire to change either one - they both have their unique characteristic sound.

 

ABECK - I'm not familiar with the trigger point mod - can you provide some detail? Just curious.

 

Edit: Btw I'm not sure I like the "no percussion drop" mod I did as well. I may find an intermediate resistor value that works to my liking.

[Musicale]

You guys are completely amazing !!

 

Musical

[ABECK]

The M3 has a lower trigger point than the B3 (In my experience). There are little metal tabs at the back of each key that can be adjusted to make contact with the key triggers earlier. I tweaked each key to my liking. I like it VERY high.

[Markyboard]

OK I'll bite (again). I don't see where those tabs are. In this video around 4:00 in there's some good views of the key and trigger "levers". Are these adjustable tabs where the key makes contact with the levers? Just really curious now.

 

[video:youtube]

[mate stubb]

The adjustable tabs are on the metal key rail - the part bolted on to the plastic key. The tab has a piece of felt mounted under it so it doesn't clack when contacting the plunger.

 

It's just a piece of metal that you can carefully bend by sticking a screwdriver in the slot.

 

http://www.hotrodmotm.com/images/misc/key_rails.jpg

[Markyboard]

Got it - thanks very much.

[ABECK]

It takes a little time and patience. If you lower the tab too much, it will actually trigger a note without even depressing the key. If I got it to that point, I would just back it off a little. But,that's my preference. Very high - allows all kinds of happy accidents.