Telefunken M15 schematics and info needed

[e.oelberg]

if you set up your machine consider atr master tape. I like it a lot, it saturates very nice (not rock'n roll though) and hiss is low.
I calibrated my studer a80 for that tape after using rmg for a few years. I use the tape a limiter

nicholas

 

[andre tchmil]

Well I'm playing with the idea of getting one.
Which one to go for , M15 or " a" version ?
Not only from a sound perspective , but also mechanical and service weaknesses.

 

[tmuikku]

Good news,

I found m15a manual from http://forum2.magnetofon.de/ download section (under AEG). Also sent it to forum gmail account!

-T

 

[living sounds]

Well I'm playing with the idea of getting one.
Which one to go for , M15 or " a" version ?
Not only from a sound perspective , but also mechanical and service weaknesses.

IMO M15, it's fully discrete (better sound and easier to service).

 

[tmuikku]

More good news!

I managed to borrow the huge M15A manual in English and scanned the whole thing into PDF  8)

I now have the manual that came with every machine (one file) and the full service manual including all machine versions and full test procedures and technical details etc. (3 files).

I'll upload the basic manual to gdiy email someday after I get the files renamed (~140Mb). However the big manual (~540Mb) took almost 16 hours to scan so I'd like to exchange it to some DIY parts or couple of euros. If someone wants it, please contact. Some stuff available in Finnish too.

 

[andre tchmil]

Top !
Will definitely contact you in the ( near ( future.

 

[tmuikku]

English manual can be found from groupdiy email account. It is in several emails due to 25mb attachment restriction.

 

[andre tchmil]

you are Da man !!!

 

[tmuikku]

you are Da man !!!

no problem. That manual is only the rightmost file in the picture in my previous message The large manual has one magnitude more pages hahaha

 

[isophase]

thats reallly cool
i own a couple M15As myself, been looking for the english manuals
sending you a PM right now

 

[Gold]

Does anyone have the documentation for a Telefunken M15 (not M15A) 1/4" deck? Is the M15A a totally different machine? Are any of the M15A documents relevant to the M15?


If anyone has an original manual that they would be willing to part with I would make it worth your while.

 

[vinyvamos]

Hi folks,

Currently searching for this M15(a) manual in English and from this thread it seems that it was uploaded to the GDIY gmail by tmuikku many years ago. Is that gmail account still operational? And if so, what is the new login info? Thanks! Otherwise, I guess I can send tmuikku a PM and see if I could get the PDFs from him somehow

 

[Gold]

I don't have docs for the M15A but I did come up with an English manual for the M15. I had Bob Shuster restore my M15 preview machine. It's a fabulous sounding machine. The machine is 7.5ips/15ips. Unlike the M15A the speeds can't be changed electronically. It's definitely my first choice over the A80VU pre for 15ips 1/4".

If I had to pick only one machine it would still be the Studer A80VU pre. The Telefunken sounds better to me and even specs slightly better with W+F. The downside is that it is picky about tape. The servo tensioning system of the A80 lets tapes sail through that would be unplayable on the M15. You have to be careful with the M15 and todays deteriorating tapes. The deck only sounds better if it can play the tape!

 

[gridcurrent]

also liking the M15.
eq around the first stage repro amplifier, unlike many later designs.
diode switching similar to Ampex AG series.
listening with my eyeballs:  it sounds excellent.

would be interesting for a revision of the first stage to accommodate high impedance heads.
how about it Abbey or JR, can it be done retaining low noise.

 

[tmuikku]

M15A manual still available, email me and I'll send you a link.

 

[abbey road d enfer]

would be interesting for a revision of the first stage to accommodate high impedance heads.
how about it Abbey or JR, can it be done retaining low noise.

The 1st stage is already optimized for HI-Z. 20uA of collector current makes it the OSI about 15 kohms, which would match a 650mH head.
A typical low-Z head with an inductance of about 8 mH would require a 1:10-ish xfmr for proper noise factor optimization. So I guess that's what Tr1 is.
You could probably connect the head directly where the secondary of Tr1 is, but there is the bias current circulating there. It's very small (0.2uA) so I doubt it would magnetize the head significantly. However I would be worried about something going wrong in the circuit and frying the head. The circuit cab easily be modded with the addition of a DC-blocking cap.
However, in order to make a good job, it is necessary to know the actual inductance of the head. There are mid-Z heads, that would require a significant redesign of the circuit. It is feasible, but takes time to optimize.

 

[MVMisho]

right now working on "ikea" style project - assembling M15a from the different parts and units (mostly fried or in need of rebuild) collected from all around Europe. All started from the set of the audio cards and head block that we've got in exchange.
I had m15 years ago and still regretting parting with it. So, there was a chance... and than the fried transport without any card but complete other vice has arise....

The service manuals available over the Internet is really incomplete, especially if one have unit with the higher serial number (our is over 5400).

I've sent the message to tmuikku, hope we can do something

 

[smilan]

More good news!

I managed to borrow the huge M15A manual in English and scanned the whole thing into PDF 8)

I now have the manual that came with every machine (one file) and the full service manual including all machine versions and full test procedures and technical details etc. (3 files).

I'll upload the basic manual to gdiy email someday after I get the files renamed (~140Mb). However the big manual (~540Mb) took almost 16 hours to scan so I'd like to exchange it to some DIY parts or couple of euros. If someone wants it, please contact. Some stuff available in Finnish too.

Can you please send me the English copy?
My email address is: asafsmilan(AT)gimail.com

 

[tmuikku]

Hi, sent you private message. MVmisho and smilan got their manuals, so will anyone else asking for it as long as this forum is alive and I get notification emails, not following the forum actively anymore. In case I'm not replying here in future try other forums like diyaudio com.

 

[Fok]

Appreciate if anyone in this group can share their experience in terms of the sonic differences between M15 and 15A as a playback machine?