3m M23 "Model 23" recorder: History and Sound

[Mystic Steamship Co.]

I just bought a M23 8 track, it's an old machine; all discrete and transformer balanced, and very very large. I am also buying a spare transport and headstack, that also comes with a remote, and I am going to completely restore the machine. I can't wait.

This is going to be my main recorder for a small analog studio I am putting up. I have no experience with 3m Machines, I know they are unique and a bit quirky, but are considered some of the very best sounding recorders. I have read that the M23 was used by EMI on some Beatles recording sessions after the Studer J37 4 tracks.

Does anybody here have any experience with these machines, or any info about the history behind them. I am especially interested in the beatles connection. Any quirks, or problems I should be prepared for, or comments on the sound of these machines?

I will post pics and sound clips of the progress once I get everything up and running. It will probably be a while, I am super busy working a gig in Texas this month, but come december I am going to head home and get to fixing the pile of gear I need to finish.

[Mystic Steamship Co.]

Here's a picture I found of a really nice M23

[calaverasgrandes]

nice, as big as a washign machine and probably as many watts.
How is it esoteric? Does it have an odd tap path?
it looks kinda like it has one of those vertical tape head arrangements where the playback/rec heads are sideways.
Reminds me of the old Ampex decks that I used to get to use.

[drumsound]

nice, as big as a washign machine and probably as many watts.
How is it esoteric? Does it have an odd tap path?
it looks kinda like it has one of those vertical tape head arrangements where the playback/rec heads are sideways.
Reminds me of the old Ampex decks that I used to get to use.

3M machines are esoteric, but sound really great. The tape path is called the Isoloop, but the heads are vertical and the tapes can be used on other machines.

[ofajen]

Does anybody here have any experience with these machines, or any info about the history behind them. I am especially interested in the beatles connection. Any quirks, or problems I should be prepared for, or comments on the sound of these machines?

Yes. I have used small format M-79s, an 8-track M-56 and currently mix to an M-23-2. You have the Beatles connection essentially right, in that Abbey Road went to the M-23-8 as a successor to the J-37-4's after considerable testing.

The sound of all those machines is really great. The Isoloop was the best-performing transport when introduced in about 1965. Really improved the audio band scrape flutter performance. So you have a recorder with the mojo of a wide-track machine with well-executed all-discrete electronics and high-quality transformer I/O that also is a high-performing transport with excellent flutter spec and superb tape-to-head contact.

Generally, the all-discrete audio cards in the M-23 and M-64/M-56 series are a bit preferred over the later channel in one big card M-79 electronics units that used 741 opamps, but even the M-79s sound great, and I always found the M-79 transports easier to work on, though much uglier.

Congrats on getting the M-23-8. It's a bit big and noisy (transport noise that is) for my situation, but should be great if you have a proper machine room.

One thing that may be a challenge is finding new or NOS 1" tape path parts (pinch rollers and capstan), if that becomes necessary. The 2" rollers are still made by Athan, but 1" parts are not so easy to locate. Best parts sources I know of are Sir Clive Kavan in the UK and Matt "Buster" Allen in Nashville.

Also, the M-23 has an AC-sync capstan motor and rim-drive. The rim-drive rubber tires in production units were not as good as the prototypes and may introduce a small bit of a wobble at the joint. I can see it on the scope trace when I do an azimuth adjust, but I don't really hear it. If it hasn't been done, you may eventually want to try to replace the rim-drive with the M-56-style belt drive.

Feel free to send a PM and perhaps we can chat by phone.

Cheers,

Otto

[Sean Sullivan]

I can't wait to hear this bad boy in action ian.

[stereopathetic_banjo]

Since you're already located in TN, I'd highly recommend contacting Matt Allen. He's a good guy with a stash of n.o.s. 3M parts, and the knowledge to get your machine up and running.

http://www.allen-sound.com

[Mystic Steamship Co.]

I have talked to Matt Allen and I am planning on having him look at it once I bring it down to Nashville. I was lucky to find a parts deck as well which will make the restoration much easier. I know it is going to be a lot of work to get this thing running and to keep it running, but I'm excited for the challange and I know it will be worth it. I just got a console that I'll be using it with as well, so I really can't wait. I will document the restoration process, and put up some sound/video clips of the machine in action once I get it working.

[Mystic Steamship Co.]

I have talked to Matt Allen and I am planning on having him look at it once I bring it down to Nashville. I was lucky to find a parts deck as well which will make the restoration much easier. I know it is going to be a lot of work to get this thing running and to keep it running, but I'm excited for the challange and I know it will be worth it. I just got a console that I'll be using it with as well, so I really can't wait. I will document the restoration process, and put up some sound/video clips of the machine in action once I get it working.

[mattallen]

Sounds good. Send me an e-mail about your timeline as I've been working overseas and throughout the US a lot this year, and next year is looking similar.