DIY reel-to-reel ?

Brett

Member
2002-01-07 6:02 pm
whaddya wanna do?

Modify one for improved performance, or build one from scratch?

The first is certainly possible, and can be done using most of the modification proceedures laid out on the boards here and elsewhere for the electronics. Mechanical mods are an area where you need some expertise, measuring tools, and an alignment tape. They can be fussy beggars.

To build one from scratch is also possible, but it would take all of the above, lots of money and dedication, time and the ability to fabricate a lot of small high precision parts. If you do it, you would be my diy hero.

However, theres no need to build from scratch. Open reels go for very little money, and can be readily modified, but it is the most expensive of DIY projects (I speak from experience). Pick a Studer or Revox or Tascam as they are still supported from the factory, although parts can be expensive. A MINT Teac, Akai GX, Pioneer RT would be an OK second tier choice.

I can answer more, but what do you want to do in detail?
 

BrianL

Member
Paid Member
2002-03-29 5:19 am
USA
Years ago, Roger Sanders, of DIY ESL fame, had an article in Audio Amateur magazine on building a reel-to-reel recorder. It was a playback-only unit that he used for dubbing, but all the mechanics were there. I have the article somewhere around here.

Personally I'd look for a good used machine to tweak. Something with a good transport and then you could modify the electronics. Brett is right about the effort required and realistically even with access to a machine shop and considerable skill you'll still end up buying a lot of pieces like pinch rollers, etc.

If you poke around likely places like local broadcast stations(assuming they haven't already tossed them years ago) you probably can find Ampex studio machines for cheap or free. These can also be found on Ebay.
 
Okay, sorry for the delay, back at school as of the other week, but all is well :)

I tried a search on eBay and found some, but seem rather old, large or are designed for studios (16 or so tracks).

Building my own fom scratch is what i was planning to do. Perhaps not for the highest quality but the learning experience along the way. Of course I would buy things liek the heads etc, but the actual mechanics i guess and the electronics to control it, and output the sound would be my main concern.

As you say Brett, its an extremely costly exercise? Is that building fom scratch of modifying units?

I've never owned or even used an open reel which is why i am extremely interested in building my own. I (from what I see) sense its nothing more than an accurate motor to spin the reel, and the head to read the signal from the tape. Also the circuitry behind the system to output the sound. Of course it's more complicated than this, but the general outline.

I will continue to search and see what I can come up with, but as of yet, I'm pretty stuck! hehe

Mike
 
I have built several, and it is not something that should be done without special knowledge. Used to be that books on tape deck construction were available, I don't know if you can still get them.

With some knowledge - and access to a good machine shop - it is not too hard. Bits and pieces are readily available on ebay - things like reel motors with breaks from Otari, head blocks, etc.

It is great fun, and perhaps the first trial should be just a reproducer deck.
 
He-he... we have considered such idea - and are still considering. However, I don't know if every manufacturer must have such forum. Nelson has special recognition that many of us don't... at least yet. So perhaps instead of trying to swamp the net with the multitude of smaller forums, just participating in ones like this one would make more sense? People interested in my input can always find me - I am quite accessible - either at the AA or here.
 

BrianL

Member
Paid Member
2002-03-29 5:19 am
USA
I still say, buy an existing machine and modify.

Ebay frequently has machines. Search on "ampex"
and you'll find many Ampexes. Also, check for "studer".
Technics RS-1500/1520/1700, etc. was a great series
of machines with fantastic transports. And ther are always
the bigger Teac or tandberg machines. Not to mention
Otari, etc.

If you really still want to build, I'd suggest reading OLD
back issues of the JAES from the 60's where you'll find
many papers on tape machine mechanical design from
the engineers of Ampex and other companies. You'll
see that the design is not exactly trivial.
 
For me those machines have mostly sentimental attachment, reminders of days gone by. Three units I have just sit somwhere in a corner collecting dust.
 

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If i can find a good pre-owned open reel taoe deck, would it be a good idea to have this restored? Are large format open reel tapes still avaiilable? I am informed these are the ultimate in analogue sonics, head and shoulders above the best turntables and LPs. I can understand why this format is used to record studio and lve perforamnces and that most CD transfers and remixes are done using multi-track open reel masters Are there prerecorded open reels out there?
 
Try One First.........

"I've never owned or even used an open reel which is why i am extremely interested in building my own. I (from what I see) sense its nothing more than an accurate motor to spin the reel, and the head to read the signal from the tape. Also the circuitry behind the system to output the sound. Of course it's more complicated than this, but the general outline."

You are essentially correct, but there are a whole bunch of things in the details.
The mechanics can need to be relatively complicated and must be precise.
There are all sorts of tricks in the play and record amplifiers, and in the record oscillator circuits Nakamichi had complex amplitude and phase compensations etc.

You can find decent R-R machines for real cheap if you hunt, and restoring is usually not too hard.
Downsides of R-R is lousy ergonmics and very high tape cost, but they do have a particular sound that can't be obtained any other way.

Eric.
 
I have built a couple of reel-to-reel decks - the electronics only though.

I started with a very dead Tandberg deck (lightning strike I guess). First I built a stereo version of the original transistor electronics (the original was mono, but with stereo heads), but using high quality parts. The sound was very good...

But to make things a bit more interesting I decided to design my own electronics. I have designed playback amps - using tubes :) The schematic can be seen on my website. I still only have one channel built - a point-to-point wired mess in a cookie tin, but it sounds great, and it's less noisy than the original circuit! I also have a design for recording electronics, but so far only in spice code...

Best regards,

Mikkel C. Simonsen

http://stiftsbogtrykkeriet.dk/~mcs/index.html
 
I've owned a number of high end recorders including a Nagra Stereo and a Studer A-80 and these days for what you can buy a used two track A-80 for its hardly worth building a R to R unless your just looking for a good metal working excercise. Presently I use a Technics RS-1500 which has by far the best transport of all the Japaneese and most other machines. It has the lowest tape skewing rate and screpe flutter of any machine except for the old 3M studio recorders which also used a closed loop transport. Since I have a number of prized master tapes I would love to build a good tube, or SS playback only stage for the 1500 to really upgrade the playback. If anone can reccomend one please let me know....

Mark
 
Mark A. Gulbrandsen said:
Since I have a number of prized master tapes I would love to build a good tube, or SS playback only stage for the 1500 to really upgrade the playback. If anone can reccomend one please let me know....
I can only recommend trying mine. I have no idea if it's better than the original 1500 playback electronics, but it should work fine on that deck also.

By adjusting R9 and R10 you should be able to adjust the high frequency response to suit the heads on your deck.

Here's a direct link: http://stiftsbogtrykkeriet.dk/~mcs/Tandberg/index.html

Best regards,

Mikkel C. Simonsen
 
Playback amp

Hi Mark!
During repair of a Revox A700,(someone poured Cuba Libre in it at a party) i built new record and playback amps.
Used an all fet srpp design ( actually a riaa stage changed for NAB compensation) with passive compensation between stages.
Souded good, utterly quiet, built with 2SK146 matched dual fets, good but maybe getting obsolete. I´ll start looking for schematic if You´re interested, long time ago - schematic by pencil on paper.
By the way, have an old Akai GX77 where logic section has gone on strike, have You seen a schematic on that model? Nice smal unit, closed loop capstan, want to to fix it for my son as he is using my Revox G36 portable model, at 21Kg it´s not that portable and actually to oldfashioned in features as they use it for liverecording and rehearsal stuff.