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Author Topic: Din Cord for Otari MX 5050 ll  (Read 15328 times)

Offline rbwtapeinterlink-Bob

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Din Cord for Otari MX 5050 ll
« on: September 09, 2007, 05:53:42 PM »
Does anyone know where a body can get din cords that terminate in RCA plugs for an Otari MX 5050ll tape deck? I was advised to check with Radio Shack, but they did not know what I was talking about, at least the store in my area of Baltimore Md.

I would also love to know where the nearest great tape deck refurbishing or repair shop is nearest to the Baltimore/Washington DC area. I may need to send the Otari off for some tender loving care before I can play some of the tapes I expect to get from the "Tape Project". After a repairman does his/her thing with the machine, I will look at the next step required to really hear all of the great music the "Tape Project's" analog tapes with provide. I can't wait for them to produce a large scale choral work by one of the great classical music masters. What a treat that will be for me. Thanks all for listening.

Bob Williams
Bob W. (African American) VPI, Ref Standard Grado, Denon 103r, Threshold, DecWare tube pre and Classe pre amp, Jolida tube phono pre amp, (Peter Gunn) modified Magnapan 1.6, Tascam 32-2B & 42B tape decks, Parasound belt drive CD transport, Pacific Valve tube DAC, VPI  TT, various upscale cables.

Offline ironbut

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Re: Din Cord for Otari MX 5050 ll
« Reply #1 on: September 10, 2007, 12:09:22 AM »
What you need is an XLR>RCA female>female adapter. There are several companies that make them and they are much higher quality than RS. Neutrik, Hosa, and expensive,.. Cardas. Unfortunately, for some reason, Otari decided to reverse polarities. To quote a fellow over on the Tape Trail;
"Usual convention is pin 3 is "hot".. Pin 1 and 2 both go to "ground"... but many makers defy this convention... and Pin 2 is "hot" and 1 and 3 is "ground".... so it is acutally useful to experiment with both, one will work "better" (louder). Rolf." Well, yours is the later according to another guy that used to post over there too ( screen named "Otari" because he has 3 5050's. Well, Pomona Electronics makes a polarity reversing adapter but only XLR>XLR. You could connect a reversing adapter to an XLR>RCA adapter to an RCA>RCA interconnect, but that's 6 connectors where 2 would normally be. Not exactly a recipe for pure sonics. What I would do, is build my own cables. You could get a pair of Neutrik female XLR connectors and a pair of male RCA plugs and some nice 4 conductor shielded microphone cable like Mogami Star Quad ( ofc copper ) solder the connectors on and add a little strain relief/heat shrink . Under $50 on the cheap or $80 if you like Bullet plugs like I do. I'm sure you could find someone to build you a pair. If this is the case, PM me and I'll see if I can find someone.
steve koto
 Sony scd 777es(R. Kern mods)> Vpi Aires>Dynavector XX-2mkll>Bent mu>CAT ultimate>CJ premeir 140>Magnepan 1.6qr(Jensen xover)Headphone Eddie Current Zana Deux>AT ad2000,HD800 ,Metric Halo ULN-2 (battery powered),
 HE Audio Jades

Offline rbwtapeinterlink-Bob

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Re: Din Cord for Otari MX 5050 ll
« Reply #2 on: September 10, 2007, 04:32:20 AM »
My Friend,
Thank you very much for this great information. In the old days we called these din cables/cords. At any rate, I will see what I can do regarding getting these cables over here in the Washington DC/Baltimore/New York/New Jersey area. If there is a major problem, I will certainly get back to you on this.

As a matter of fact, if you would, please see if you can find someone to do this for me and pass on the names and where to contact. That would be a great relief for me. "Ask and you shall recieve" is wonderful. Thank you again for your quick response and offer to assist me.

Bob Williams
Bob W. (African American) VPI, Ref Standard Grado, Denon 103r, Threshold, DecWare tube pre and Classe pre amp, Jolida tube phono pre amp, (Peter Gunn) modified Magnapan 1.6, Tascam 32-2B & 42B tape decks, Parasound belt drive CD transport, Pacific Valve tube DAC, VPI  TT, various upscale cables.

Offline jdcolombo

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Re: Din Cord for Otari MX 5050 ll
« Reply #3 on: September 10, 2007, 06:51:45 AM »
My Friend,
Thank you very much for this great information. In the old days we called these din cables/cords. At any rate, I will see what I can do regarding getting these cables over here in the Washington DC/Baltimore/New York/New Jersey area. If there is a major problem, I will certainly get back to you on this.

As a matter of fact, if you would, please see if you can find someone to do this for me and pass on the names and where to contact. That would be a great relief for me. "Ask and you shall recieve" is wonderful. Thank you again for your quick response and offer to assist me.

Bob Williams

I think Steve is correct.  The Otari has what are known as XLR or "Canon" connectors for both output and input.  You can fairly easily make up a set of adapter cables if you can solder.  If not, you can get adapter cables from this place on the internet:

http://search.cablestogo.com/?qu=XLR

However, if Steve is right and the Otari doesn't use the "standard" wiring, these cables may not work (note that my Revox PR99 is the same way: it is wired for pin 2 to "high," pin 3 to "low" and pin 1 to shield; to make an adapter cable, you connect pins 1 and 3 to the "ring" of the RCA connector, and pin 2 to the tip).

However, you should know that adapter cables aren't necessarily the full solution.  When you connect "pro"-style gear like the Otari to consumer equipment, there are two problems.  The first is that pro gear uses "balanced" audio inputs and outputs that have a much different electrical impedance from "unbalanced" RCA connections on consumer gear.  The second problem is that pro-level gear is generally designed to output a maximum of 1.4 volts, and 0VU on pro tape machines is normally referenced to an input of 775 millivolts.  Consumer gear, on the other hand, typically outputs about 320 millivolts (-10db referenced to 1 volt).  That means that most consumer gear cannot generate enough output to drive the inputs of a professional tape recorder, and it also means that the outputs of the pro gear can easily overload the inputs of consumer gear (because the pro gear is outputting 1.4 volts into consumer gear expecting about 320 millivolts!).  The output issue usually isn't a problem, because you can easily dial down the output level using knobs on the front of the recorder.  The input level issue, however, is a major problem IF you want to do any recording from your consumer equipment, because you won't be able to raise the level enough on the recording inputs to get a decent recording.  So if you're just going to play Tape Project tapes on your machine, an adapter cable is probably all you need (and if you're going to use the Bottlehead repro amp, you don't even need that, because you'll be connecting the play head output directly to the Seduction and bypassing your internal repro amp).

If you want to do recording, then you have a potential problem because of the level mis-match.  On many pro tape decks, there is some way to adjust the line-level input sensitivity.  So, one thing you can do is use a simple adapter cable, and adjust the recorder's input sensitivity to be more compatible with consumer gear.  But if you do this, then the recorder will no longer be "in spec" for pro use (for example, you couldn't then hook the recorder to a pro mixing console, because it would overload your recording inputs).  If you're just going to be using the thing to record from your stereo, then it probably doesn't matter, unless you have to turn up the gain on the recorder's input so far that you get excessive noise.

So . . . there is another solution for hooking pro gear to consumer gear.  That solution is to get a "converter box" that does both impedance matching and level matching.  These boxes have RCA inputs and outputs along with XLR (3-pin) inputs and outputs.  Here is an example of one:

http://www.datavideo.us/fs/products/bac03_fs.htm

These boxes "upconvert" the level from consumer gear to pro level, and downconvert the level from pro gear to consumer levels.  Don't know about their sound quality, though; on that front, your best bet probably is to bypass your Otari's repro amp completely, and use the Bottlehead repro amp provided by The Tape Project.

John Colombo

John Colombo
Savoy, IL

Offline rbwtapeinterlink-Bob

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Re: Din Cord for Otari MX 5050 ll
« Reply #4 on: September 10, 2007, 07:28:36 AM »
Dear John,
What can I say but thank you very much. I have yet another response to my cable problem and real friends who come through with answers that will get me what I am looking for. I do appreciate.

Tell me John, what tape deck did you finally decide to purchase. I know in an earlier post you mentioned that you had found a Tascam 32B while looking at other tape decks. I did eventually purchase the Tascam unit, but now must have it setup for 911 tape. As you know, I purchased the 32B from Vince at Audio Proz and must say that the deck is in superb condition. However, Vince is not convinced that there is a need to change from the NAB standard established back many years ago when Ampex set the stardard in tape and therefore the standard regarding tape deck setups.

Well, I've said enough for this post. I look forward to hearing which tape deck you finally purchased, what condition it's in and what changes you plan to have done to it? Thanks again my friend for all of your help.

Bob Williams
Bob W. (African American) VPI, Ref Standard Grado, Denon 103r, Threshold, DecWare tube pre and Classe pre amp, Jolida tube phono pre amp, (Peter Gunn) modified Magnapan 1.6, Tascam 32-2B & 42B tape decks, Parasound belt drive CD transport, Pacific Valve tube DAC, VPI  TT, various upscale cables.

Offline jdcolombo

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Re: Din Cord for Otari MX 5050 ll
« Reply #5 on: September 10, 2007, 11:59:04 AM »
Hi again, Bob.

Out of curiosity, I check on the actual standards for XLR cables.  What I found was that the AES standard wiring is for Pin 2 to be "high" or "hot" and Pin 3 to be "low," with the shield to pin 1.  Apparently, a lot of companies in North America reversed pins 2 and 3, but the Otari (and my Revox) actually follows AES standards.  That means that the adapter cables I gave you the web site for should work fine for you, IF all you need is a cable and not a "black box" converter.

John C.
John Colombo
Savoy, IL

Offline jdcolombo

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Re: Din Cord for Otari MX 5050 ll
« Reply #6 on: September 10, 2007, 12:28:34 PM »
Dear John,
However, Vince is not convinced that there is a need to change from the NAB standard established back many years ago when Ampex set the stardard in tape and therefore the standard regarding tape deck setups.

Bob Williams

Well, Vince is correct that virtually every tape machine sold in the U.S. was set to NAB eq standards, and he probably doesn't quite understand that The Tape Project tapes are using IEC equalization, rather than the US standard NAB eq.  Doc has a post somewhere here on the web site explaining why they chose IEC equalization over NAB.  I understand his reasoning, but it means that a whole lot of stock tape decks sold in the US market aren't compatible with The Tape Project without some modification.  For example, the Revox PR99 that I just acquired is set up to NAB eq, even though Revox sold a ton of these things in Europe set to IEC eq.  Unless you have a machine with switchable EQ (e.g., the Otari 5050 series, or many of the true professional decks like the Studer 810), you either need to rewire your machine so that the playback head output bypasses the internal playback electronics and can be connected directly to the Bottlehead that Doc is selling as part of The Tape Project, or you need to have the machine reset to IEC eq.  If you do the latter, however, then you won't be able to play commercially-recorded tapes made in the US, which were all made for NAB eq.  You could certainly do your own recording, though that would require also modifying the record amplifier in your deck to IEC spec.

In my case, since Revox sold so many of the PR99's in Europe with IEC eq, I can get a set of record and playback amplifier cards that simply plugs in to the machine in place of the NAB cards at a reasonable (e.g., cheap) price, and I'm good to go at least to start with (though the Bottlehead repro amp certainly will give overall better sound, and I'll get one eventually).

I think you can get a Bottlehead Seduction via Doc for about $550 assembled (they sell the kits for less).  While that's not a small sum, I wouldn't spend a ton on getting the 32 redone for IEC eq; instead, I'd have a tech run wires from the playback head to two new RCA jacks mounted somewhere on the back of the deck, and get the Bottlehead to use as the playback amplifier.

John C.
John Colombo
Savoy, IL

Offline docb

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Re: Din Cord for Otari MX 5050 ll
« Reply #7 on: September 10, 2007, 12:45:29 PM »
Just to clarify, a stock MX-5050BII has a little switch on the back to select NAB or IEC playback EQ, and it also has an output level switch that can be set for +4 or -10dBm. The transformer outputs float, so it would be easy to use an XLR to RCA adapter.
Dan "Doc B." Schmalle
President for Life, Bottlehead Corp.
Managing Director - retired, The Tape Project

Offline rbwtapeinterlink-Bob

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Re: Din Cord for Otari MX 5050 ll
« Reply #8 on: September 10, 2007, 01:21:39 PM »
Everyone has been so great here. What a wonderful group of people. I am more amazed daily as I am forced to ask questions about many things and areas I am totally unfamiliar with. I can't thank each of you enough for all the assistance you've provided me. I am truly humbled by your attentiveness and sharing.

Bob
Bob W. (African American) VPI, Ref Standard Grado, Denon 103r, Threshold, DecWare tube pre and Classe pre amp, Jolida tube phono pre amp, (Peter Gunn) modified Magnapan 1.6, Tascam 32-2B & 42B tape decks, Parasound belt drive CD transport, Pacific Valve tube DAC, VPI  TT, various upscale cables.

Offline rbwtapeinterlink-Bob

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Re: Din Cord for Otari MX 5050 ll
« Reply #9 on: September 10, 2007, 01:37:35 PM »
Dear Doc B.,
Are you saying that I don't need to worry about which pin is in which position or does the XLR female/male come standard. Also It sounds as if I won't need to have the 5050 setup for equilization since I can change from NAB myself.

This machine also comes with a test oscilator and external oscilator input. What is that all about? This tape deck is totally new to me and appears to have many useful features.  I am sure that I will have to get some things done to it before I can really get down to the business of playing the "Tape Project" tapes. Pinch rollers, belts, tape heads will probally be needed right away. The machine has not been used in many years and was used to record small choirs and piano, cello and flute trio. I would love to have some of those recordings. Thanks for your response.

Bob W
Bob W. (African American) VPI, Ref Standard Grado, Denon 103r, Threshold, DecWare tube pre and Classe pre amp, Jolida tube phono pre amp, (Peter Gunn) modified Magnapan 1.6, Tascam 32-2B & 42B tape decks, Parasound belt drive CD transport, Pacific Valve tube DAC, VPI  TT, various upscale cables.

Offline ironbut

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Re: Din Cord for Otari MX 5050 ll
« Reply #10 on: September 10, 2007, 09:09:58 PM »
I've been scanning some TapeOp forum postings on the XLR configuration on the 5050Bll and I've seen posts with owners with machines with both pin 3 and pin 2 being "hot". Apparently, they switched at some point. If you check the back of your deck, some of them have a sticker that states how it's configured. If you don't have a meter to test it, you can try emailing Otari with your serial # and they should be able to tell you for sure. I would think that they got lots of requests for adapters so ask if they still sell them. Other places to try and get an adapter cables made (I think that and adapter cable is preferable to an adapter + interconnect unless you have extra cables that you really like) is; http://www.redco.com/   They make their own line of adapters and pro cables ( large snakes used for concerts etc). They also carry connectors from several other companies. Another source for more "audiophile custom cables is VH Audio. Chris Venhaus used to make special orders and his cables are an excellent value. He caters to the DIY community but he's very cool and even his lowest priced cables ain't too shabby.   http://www.vhaudio.com/products.html
If you want to try the adapters (if they are wired correctly) a quick and easy source for those would be your local Guitar Center. These XLR cables are how mixers and almost everything in those racks of outboard gear that sound guys have at the sound-board. Just make sure that they don't try and sell you cables/adapters with level matching components in them ( you already have that in your 5050 and the reason for this extra problem listening to your tapes)
In closing, I'd say that it would be a mistake to spend too much money on these cables/adapters. The quality of them might make a 5% improvement to the sound. Bypassing the onboard playback electronics and using an upgraded Seduction or Doc's Tube Repo Amp is closer to a 50% improvement.

steve koto
 Sony scd 777es(R. Kern mods)> Vpi Aires>Dynavector XX-2mkll>Bent mu>CAT ultimate>CJ premeir 140>Magnepan 1.6qr(Jensen xover)Headphone Eddie Current Zana Deux>AT ad2000,HD800 ,Metric Halo ULN-2 (battery powered),
 HE Audio Jades

Offline docb

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Re: Din Cord for Otari MX 5050 ll
« Reply #11 on: September 10, 2007, 09:58:16 PM »
According to the schematic I'm looking at the output is floating, balanced. That means the secondary of the output transformer is not grounded to the signal or chassis ground of the tape recorder, and in that case a meter can't tell you anything about signal phase. If the output is floating the worst thing that can happen is the output signal phase gets flipped if it the pins are wired backwards. Not a huge deal, no damage will occur. FWIW I took my spec from an Otari service manual schematic, and FWIW the MX5050BII I have here has a hand written label that says pin 3 hot, pin 2 cold, pin one ground. This would imply that there is no continuity between pin 2 and pin 1 and the output is indeed floating.

A simple test is to measure resistance from pin 3 to ground and from pin 2 to ground. If the secondary is grounded one of those pins will read 0 ohms and the other will read just a fraction of an ohm. The fractional pin will be the hot. If it reads infinity on both pins the output is floating.

If I get a chance tomorrow I will check whether the output on the 5050 I have here is floating or not.
Dan "Doc B." Schmalle
President for Life, Bottlehead Corp.
Managing Director - retired, The Tape Project

Offline rbwtapeinterlink-Bob

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Re: Din Cord for Otari MX 5050 ll
« Reply #12 on: September 13, 2007, 12:02:15 PM »
Thank you Doc B. I really appreciate and I appreciate all input. Thank you so much guys.

Bob W.
Bob W. (African American) VPI, Ref Standard Grado, Denon 103r, Threshold, DecWare tube pre and Classe pre amp, Jolida tube phono pre amp, (Peter Gunn) modified Magnapan 1.6, Tascam 32-2B & 42B tape decks, Parasound belt drive CD transport, Pacific Valve tube DAC, VPI  TT, various upscale cables.

Offline ironbut

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Re: Din Cord for Otari MX 5050 ll
« Reply #13 on: September 24, 2007, 07:22:03 PM »
Regarding the XLR>RCA adapter/interconnect, I found a small cable builder (small operation not cables) that is willing to build cables to spec.. His prices a reasonable and the ones I've heard are excellent (custom headphone cables). Here's some prices on different connectors and dielectric configurations.
You have 2 different choices for a 1m RCA to XLR IC.

Option 1 is my wire with either black or carbon sleeving.

Neutrik RCA: $145
Swithcraft RCA: $150
WBT style RCA: $160
Eichman Bullet RCA: $170

Option 2 is my wire covered in cotton insulation then covered in carbon sleeving. This helps insulate the cable as cotton is known to be a great insulator and lowers the capacitance level of the cable.

Neutrik RCA: $175
Swithcraft RCA: $180
WBT style RCA: $190
Eichman Bullet RCA: $200


I use high grade silver plated copper wire (75% silver, 25% copper) covered in 2 layers of Kapton to protect from oxidation (humidity and air) then in Teflon to protect the wire itself. The wires are then twisted together and shielded using a silver shield. High grade 4% silver solder is used.
Alex's web site is apuresound.com
steve koto
 Sony scd 777es(R. Kern mods)> Vpi Aires>Dynavector XX-2mkll>Bent mu>CAT ultimate>CJ premeir 140>Magnepan 1.6qr(Jensen xover)Headphone Eddie Current Zana Deux>AT ad2000,HD800 ,Metric Halo ULN-2 (battery powered),
 HE Audio Jades

Offline rbwtapeinterlink-Bob

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Re: Din Cord for Otari MX 5050 ll
« Reply #14 on: September 30, 2007, 01:46:21 PM »
I want to thank everyone who contributed comments. I am new at this and need all of the assistance I can get. Steve thank you for the resources. It was very kind of you and everyone to help me in this way.

Bob W.
Bob W. (African American) VPI, Ref Standard Grado, Denon 103r, Threshold, DecWare tube pre and Classe pre amp, Jolida tube phono pre amp, (Peter Gunn) modified Magnapan 1.6, Tascam 32-2B & 42B tape decks, Parasound belt drive CD transport, Pacific Valve tube DAC, VPI  TT, various upscale cables.