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Otari MX-5050 Review (Reel to Reel Tape Deck)

MakeMineVinyl

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I don't recall any consumer open reel machines having azimuth and auto bias controls, like the better cassette decks had. Maybe some had them, but I don't remember.
The Sony deck I have has full head adjustability, and I believe this applies to all Sonys. Come to think of it, I don't recall seeing a consumer deck which didn't have an adjustable head. Ironically, it is some professional recorders which didn't have adjustable heads. Some of those were revised over time to allow playback head adjustments to account for tapes from other studios which were recorded on a machine with record head azimuth errors.

Instrumentation recorders like the type which were used to record the space missions never had adjustable heads. They had precision milled head mounts so that you just bolted new heads down and they were aligned.
 

anmpr1

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The Sony deck I have has full head adjustability, and I believe this applies to all Sonys. Come to think of it, I don't recall seeing a consumer deck which didn't have an adjustable head. Ironically, it is some professional recorders which didn't have adjustable heads. Some of those were revised over time to allow playback head adjustments to account for tapes from other studios which were recorded on a machine with record head azimuth errors.

Instrumentation recorders like the type which were used to record the space missions never had adjustable heads. They had precision milled head mounts so that you just bolted new heads down and they were aligned.
I was referencing auto bias/azimuth. Certainly it was more helpful on a four track cassette deck operating at 1 7/8 ips, for getting best sound. An example is the Nakamichi Dragon deck. I don't recall any of those auto features on an open reel deck. Maybe some had them.
 

anmpr1

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What parts typically need replacing? belts? Available. Springs? Same. Caps/resistors? Same. Motors and pots? Can be reconditioned/cleaned. Pinch rollers? idler wheels?
Pinch rollers can be rebuilt. Belts can be replaced. Electronic parts can be soldered in. Tape heads? There are probably outfits that recondition what you have. NOS is likely not available.

The outfit that sold me my Dyna preamp mod parts sells electronic replacement parts for Revox and Studer, for instance.

 

MakeMineVinyl

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I was referencing auto bias/azimuth. Certainly it was more helpful on a four track cassette deck operating at 1 7/8 ips, for getting best sound. An example is the Nakamichi Dragon deck. I don't recall any of those auto features on an open reel deck. Maybe some had them.
Open reel decks that I know of do not have auto bias nor automatic head adjustment. There might be some Japanese deck which did it, but I haven't seen it.
 

MakeMineVinyl

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What parts typically need replacing? belts? Available. Springs? Same. Caps/resistors? Same. Motors and pots? Can be reconditioned/cleaned. Pinch rollers? idler wheels?
The missing ingredient is knowledge and experience in dealing with the more in the weeds aspects of servicing an open reel. Sure if someone just wants to mess around with an expendable consumer open reel, fine, but I would expect the results would be about as good as a layman attempting a valve job on a car with no prior experience (video or no video).

Also, you're not mentioning the heads - these are the most vital part in any tape machine, and if they're worn, nothing else matters. And the heads are one of the most likely parts in a machine which will need attention, and consumer heads were not built to be long lasting like professional heads which had deep gaps. There are no manufacturers who make heads for consumer machines anymore. There are a couple who make new heads for professional machines, but that does no good for consumer machines. Part of the skill in servicing a tape machine is being able to know how to spot the condition of the heads, and more importantly, what to do about dealing with any problems.;)
 
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Siwel

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I worked directly for Otari during the halcyon days when these were sold from new and have a soft spot for them as a result. I had an ongoing commercial relationship with the company after I left their direct employ as I represented their machines in the northwest until they ceased distribution through their pro channel. Those are my caveats and proformas but it has been quite some time since.

Typical S/N ratios hovered in the mid 60s for new machines so I immediately suspected a problem with Amir’s sample. Not Amir’s measurements of course but rather with the deck.
This could be down to any number of variables including age, calibration of eq or bias, tape age and or compatibility with existing settings, worn heads or the like And there are plenty of other potential problem areas for a machine as old as any of these are at this point.

Regarding heads, these were typically supplied by Nortronics for the MX5050 series although 1/2” 8 track units received heads made in house by Otari. The standard 1/4“ heads were typically replaced when worn rather than being relapped as this was most cost effective and generally results in faster, more convenient and generally more satisfying repair. For instance, the standard heads must be relapped with care since they aren’t exceptionally meaty and require a light touch with the abrasives if one doesn’t want to overcook the end product. At the time, getting new heads for Otari or Teac semi pro machines was not prohibitively expensive. New and remanufactured heads for most Otari models are still available from JRF Magnetics (John French) who supplied service and spares even when Otari was still in the business. A reliable source, that’s where I’d go to find replacement heads for this and other quality recorders.

By the way, the 5050 series was the entry level for Otari recorders, this including Amir’s unit. 5050s were made across three generations with many sub variants in between and some final production that might loosely be considered a fourth generation but was really a repackaging. Silver front units are the oldest with the rest of the one box 5050 two tracks generally being black. This is just an easy way to recognize the earliest units which are less fully featured and IMO are a little less desirable than later production.

All 5050 series however hewed to the same design philosophy which, broadly speaking, attempted to provide a full range of pro features at an acceptably sensible premium over lesser, more consumer focused decks. Common features include front panel bias and eq controls, 1kHz oscillator to set bias, splicing block on head cover, pro level inputs/outputs on xlr connectors-not all of which models were truly delivered truly balanced, transformers being an option on many early 5050s including the well regarded 1/2 inch eight track (8D). If you get a 5050 don’t automatically assume the XLR connector means you have true balanced ins and outs. Some do, some don’t depending on vintage and options specified for the particular model and the original buyer’s choice of transformers.

it’s been many years since I or anybody else for that matter has worked for Otari in the capacity of supplying tape machines but i will keep an eye on this thread and stand by especially if I can answrer any questions (big if!) owners may have about the many variations these machines were originally sold in.
 

MakeMineVinyl

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I worked directly for Otari during the halcyon days when these were sold from new and have a soft spot for them as a result. I had an ongoing commercial relationship with the company after I left their direct employ as I represented their machines in the northwest until they ceased distribution through their pro channel. Those are my caveats and proformas but it has been quite some time since.

Typical S/N ratios hovered in the mid 60s for new machines so I immediately suspected a problem with Amir’s sample. Not Amir’s measurements of course but rather with the deck.
This could be down to any number of variables including age, calibration of eq or bias, tape age and or compatibility with existing settings, worn heads or the like And there are plenty of other potential problem areas for a machine as old as any of these are at this point.

Regarding heads, these were typically supplied by Nortronics for the MX5050 series although 1/2” 8 track units received heads made in house by Otari. The standard 1/4“ heads were typically replaced when worn rather than being relapped as this was most cost effective and generally results in faster, more convenient and generally more satisfying repair. For instance, the standard heads must be relapped with care since they aren’t exceptionally meaty and require a light touch with the abrasives if one doesn’t want to overcook the end product. At the time, getting new heads for Otari or Teac semi pro machines was not prohibitively expensive. New and remanufactured heads for most Otari models are still available from JRF Magnetics (John French) who supplied service and spares even when Otari was still in the business. A reliable source, that’s where I’d go to find replacement heads for this and other quality recorders.

By the way, the 5050 series was the entry level for Otari recorders, this including Amir’s unit. 5050s were made across three generations with many sub variants in between and some final production that might loosely be considered a fourth generation but was really a repackaging. Silver front units are the oldest with the rest of the one box 5050 two tracks generally being black. This is just an easy way to recognize the earliest units which are less fully featured and IMO are a little less desirable than later production.

All 5050 series however hewed to the same design philosophy which, broadly speaking, attempted to provide a full range of pro features at an acceptably sensible premium over lesser, more consumer focused decks. Common features include front panel bias and eq controls, 1kHz oscillator to set bias, splicing block on head cover, pro level inputs/outputs on xlr connectors-not all of which models were truly delivered truly balanced, transformers being an option on many early 5050s including the well regarded 1/2 inch eight track (8D). If you get a 5050 don’t automatically assume the XLR connector means you have true balanced ins and outs. Some do, some don’t depending on vintage and options specified for the particular model and the original buyer’s choice of transformers.

it’s been many years since I or anybody else for that matter has worked for Otari in the capacity of supplying tape machines but i will keep an eye on this thread and stand by especially if I can answrer any questions (big if!) owners may have about the many variations these machines were originally sold in.
I bought the first Otari MX 7300 8 track 1" machine delivered into the US in the middle 70s. You might have had something to do with it. I have the guy's card who I dealt with; I think his name was Brian Trangle or something like that.
 

Siwel

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it takes no genius on my part to infer that you dealt with Brian Trankle (minor spelling correction there for you) not me. Or at least you got his card and not mine. I got there just in time to walk the second or third MX7300 through delivery It was sold to Bob Burke Studios in San Francisco, (great guy) but I have little doubt you and I have probably met or spoken on the phone. My name is Lew so if you remember speaking to a guy with a name like mine who wasn’t Japanese and also wasn’t Brian, well, then you probably dealt with me. At the time Brian and I were the only Americans in sales and marketing but there were a couple others in support roles. Brian rolled out the original 5050s and the MX7300 which was a beast of an 8 track (But not without some teething problems as you may have experienced). I was the guy that rolled out the MKII versions of those as Brian left less than a year after I got there and I assumed his job. By that time the company was growing by leaps and bounds. We had hired additional folks and began introducing the better known multi tracks like the MTR90, the MX70 and MX80 (which between them replaced the 7300).

I started with Otari in 1976 and left in 1979 but remember the entire experience quite fondly, met a ton of people and had a great time living in SF and traveling around the world talking to engineers, producers, dealers and other manufacturers. It was an exciting time to be in the biz and led to a lifelong career in audio. Otari was a good place to work, we were all genuinely enthusiastic about the gear we sold and I can say that the company did its best to provide a high value alternative to the Ampex/3M/MCI multi tracks that we competed with by the end of the multitrack era. But the bread and butter was always the 5050 series.
 

dfuller

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What parts typically need replacing? belts? Available. Springs? Same. Caps/resistors? Same. Motors and pots? Can be reconditioned/cleaned. Pinch rollers? idler wheels?
The record and playback heads are sacrificial to the tape, so they have to be replaced eventually.
 

MakeMineVinyl

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it takes no genius on my part to infer that you dealt with Brian Trankle (minor spelling correction there for you) not me. Or at least you got his card and not mine. I got there just in time to walk the second or third MX7300 through delivery It was sold to Bob Burke Studios in San Francisco, (great guy) but I have little doubt you and I have probably met or spoken on the phone. My name is Lew so if you remember speaking to a guy with a name like mine who wasn’t Japanese and also wasn’t Brian, well, then you probably dealt with me. At the time Brian and I were the only Americans in sales and marketing but there were a couple others in support roles. Brian rolled out the original 5050s and the MX7300 which was a beast of an 8 track (But not without some teething problems as you may have experienced). I was the guy that rolled out the MKII versions of those as Brian left less than a year after I got there and I assumed his job. By that time the company was growing by leaps and bounds. We had hired additional folks and began introducing the better known multi tracks like the MTR90, the MX70 and MX80 (which between them replaced the 7300).

I started with Otari in 1976 and left in 1979 but remember the entire experience quite fondly, met a ton of people and had a great time living in SF and traveling around the world talking to engineers, producers, dealers and other manufacturers. It was an exciting time to be in the biz and led to a lifelong career in audio. Otari was a good place to work, we were all genuinely enthusiastic about the gear we sold and I can say that the company did its best to provide a high value alternative to the Ampex/3M/MCI multi tracks that we competed with by the end of the multitrack era. But the bread and butter was always the 5050 series.
A few weeks after I took delivery of my MX7300, three Japanese gentlemen showed up at my studio. They weren't very good at expressing themselves in English and I came away wondering just what the purpose of the visit was. I mentioned to them that the machine had excessive power supply hum which I had remedied by (I think) adding filter capacitance before their visit. They nodded, left, and I never heard anything ever again from them or Otari.

That's OK though because the machine was well behaved and sounded great, especially at 30 ips. I ended up selling it when I closed my studio. Man, I wish I could have kept that machine - this is it in my studio.

MX7300.jpg
 
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amirm

amirm

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What parts typically need replacing? belts? Available. Springs? Same. Caps/resistors? Same. Motors and pots? Can be reconditioned/cleaned. Pinch rollers? idler wheels?
This list can go super deep depending on the unit. Ki Choi who is the master R2R collector and repair person has gone as far as cloning PLDs (programmable logic devices) to rescue some old units. Consumer decks were not made to last 40 to 50 years so one could run into many major problems including motors and such. Definitely a different animal than restoring a piece of electronics from that era.
 

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@makemine vinyl:
Yeah, that’s an early one. The 7300 wasn’t a big seller compared to the large frame recorders that followed but it was durable and robust and pretty easy to work on.

I was frequently asked to do studio tours with various Otari Japan personnel especially when the MTR 90 was being developed. it was almost always awkward but they wanted to see their machines in use and to get a feel for what owners needed. Hope you got a good price on your machine. Buying the early ones took a leap of faith. But it usually worked out well because Otaris tended to be both reliable and durable in the long run and matched specs with more expensive machines. But you know if you buy the first of anything you are pioneering and the first 7300s did have some issues. Multitracks are complex and hard working machines. Some issues are virtually inevitable with all of them. As the 7300 was the first of Otari’s efforts in that particular direction I have to say you were brave to jump in! I’m glad it gave you good service.
 

Siwel

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While we are on topic of other Otari decks, here is a super dedicated Otari R2R audiophile whom I visited a while back: https://www.audiosciencereview.com/...e-aficionado-and-audiophile-john-brooks.1325/

He had two MTR-15s:

index.php
The MTR15 was the last of its type and by that time Otari was building them at a different level of performance and tape handling than a 5050 or even machines like the 7300. Different critter.

It was hoped by some of us to be open loop (no pinch roller) like the MTR90 but as we see it had a pinch roller. That didn’t matter in use as it handled tape very well despite the older style of transport. It came at the very end of the era and is surely Otari’s most advanced two track.
 

anmpr1

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Regarding heads, these were typically supplied by Nortronics ...

The missing ingredient is knowledge and experience in dealing with the more in the weeds aspects of servicing an open reel.

Nortronics is a legacy name I hadn't remembered in a while. The link below takes you to the outfit that claims to have purchased the entire Nortronics inventory, and they also refurb tape heads. I have no relation to them, but if I had a top notch deck, these folks would be on my short list of people to contact.

As they state on their Web, the 'problem' with open reel, is not only replacement part scarcity, but the knowledge to know what to do with the parts is itself becoming scarcer, as the engineers of old leave us.

 

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Nortronics is a legacy name I hadn't remembered in a while. The link below takes you to the outfit that claims to have purchased the entire Nortronics inventory, and they also refurb tape heads. I have no relation to them, but if I had a top notch deck, these folks would be on my short list of people to contact.

As they state on their Web, the 'problem' with open reel, is not only replacement part scarcity, but the knowledge to know what to do with the parts is itself becoming scarcer, as the engineers of old leave us.

Several of Otari’s engineers were adept at relapping heads although factory practice was to replace 5050 series heads as required but would relap 8 track (8D) and (curiously perhaps) 5050 mono heads as they were the most expensive single parts on the 8 track units and were constructed with sufficient material to allow for the procedure. And yes, the 5050 was available in mono full track to serve AM radio stations and the like. The MX and MTR machine series heads were made to be refurbished in line with standard practice. But the standard (5050) Nortronics heads, while they could be relapped (perhaps only once though) by an experienced tech we generally just replaced Them. Lapping required more time, care and energy than it was thought to be worth so ‘twas easier and ultimately cheaper to replace them. That‘s less true today as these once standard parts are now specialty items so you do what you have to do to keep them in service. You wouldn’t want to replace 24 track heads routinely then or now, and I wonder (fear?). what a new 24 track full head stack would cost today for even the most commercially successful multi-track recorders.
 

MakeMineVinyl

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Several of Otari’s engineers were adept at relapping heads although factory practice was to replace 5050 series heads as required but would relap 8 track (8D) and (curiously perhaps) 5050 mono heads as they were the most expensive single parts on the 8 track units and were constructed with sufficient material to allow for the procedure.
Here's the 8 track 1" heads on my sadly departed Otari MX7300. For those not familiar with professional heads, the tops and bottoms of the heads had grooves cut so that the edges of where the tape rode would never go below the face of the head. Consumer machines (and some Nortronics heads) didn't use these grooves and as the heads wore, the tape could ride up over the worn-in groove and tape contact would be compromised.

Heads.jpg


This is the headblock from my current Ampex 354 which also has these grooves.

Ampex 354 Headblock.jpg


Now back to our regularly scheduled non-wonky thread. :cool:
 

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anmpr1

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You wouldn’t want to replace 24 track heads routinely then or now, and I wonder (fear?). what a new 24 track full head stack would cost today for even the most commercially successful multi-track recorders.

I didn't see a price list, but from the JRF site:

Why pay ...thousands of dollars for new heads... when JRF can bring your worn (but relappable) heads up to new factory spec for a fraction of the cost.

I suppose those who use these machines for a living are comfortable with it. Or have no choice. Sort of like owning a Ferrari Testarossa. If you are worried about routine maintenance costs, you shouldn't have one parked in your driveway in the first place.
 

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Here's the 8 track 1" heads on my sadly departed Otari MX7300. For those not familiar with professional heads, the tops and bottoms of the heads had grooves cut so that the edges of where the tape rode would never go below the face of the head. Consumer machines (and some Nortronics heads) didn't use these groov88\\

This is the headblock from my current Ampex 354 which also has these grooves.

View attachment 160918

Now back to our regularly scheduled non-wonky thread. :cool:
It's fun for me to see your pics as I have mostly just memories from those days. You may recall better than I do but if I actually do recall correctly it was JRF that originally supplied the 8 tr. heads for your recorder. In any event as is clear from your photo, they were proper built. For certain specialty heads, like those on the 1/2" machine the factory did take on the production but since it's so specialized, at first only one guy at the factory could build them and this was a production bottleneck for a painfully long period of time. I don't see any gap on your 354 heads, you are probably good for a long time. Original electronics on that? Remember Inovonics? :)

I wouldn't mind a 5050 for myself but mainly for sentimental reasons. I have a few tapes but no way to play them. I do have this however, a tiny memento from those days. I just now took these pics just for the two of us. Well, Amir too since he still has his 5050. Possibly the only extent NOS Otari reel in the world! I should send it to Amir for a thorough re-test on his Otari with a proper Otari reel! Can't be too fussy about these things!

As you know, this came in the box with your new machine. You got one to get you started cause otherwise it would be, somewhat awkward to roll tape!
 

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anmpr1

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Or, if you're not sure you want to make the initial investment, for $130.00 you can try the 'audio tape warmer' from nomad...


9 Tape Models that give you the real sound of the vintage tape machines

Otari MX-80 2-inch 24-track
Otari MTR-90 2-inch 24-track
Ampex MM1200 2-inch 24-track
Ampex ATR-102 half-inch two-track
Tascam ATR60-16 1-inch 16-track
Studer A80 Mk II 2-inch 24-track
Studer A827 2-inch 24-track
Studer A820 2-inch 24-track
MCI JH24 2-inch 24-track

img.jpg
 
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