wm-d6c poor recording quality.

[Jimmy M]

Hi everyone.
I've been trying to get to the root cause of the above problem; despite being scrupulously cared for and serviced, my walkman just doesn't record as well as it has. I would say I bought it new in 1994 and it has had a lot of use. I'm thinking head wear, but am baffled by the fact it plays back factory produced and old tapes of mine made on it amazingly - like new. I am thinking could it be the record switch may just be dirty inside, oxidised? Originally, and for years it made very good recordings on even type 1. Now it only really sounds ok on metal tapes or if I happen across a good new stock SA. But never great. Muddy, mildly distorted treble. Does anyone kindly have some advice?
Jim

[A.N.T.]

Hi everyone.
I've been trying to get to the root cause of the above problem; despite being scrupulously cared for and serviced, my walkman just doesn't record as well as it has. I would say I bought it new in 1994 and it has had a lot of use. I'm thinking head wear, but am baffled by the fact it plays back factory produced and old tapes of mine made on it amazingly - like new. I am thinking could it be the record switch may just be dirty inside, oxidised? Originally, and for years it made very good recordings on even type 1. Now it only really sounds ok on metal tapes or if I happen across a good new stock SA. But never great. Muddy, mildly distorted treble. Does anyone kindly have some advice?
Jim

Hi Jim,

Welcome to Tapeheads!

Most likely this problem is connected to an incorrect biasing - but what is the reason for that would be near impossible to guess without looking at the unit with at least an oscilloscope. It could be oxidised switch or a faulty component, it could be even a head wear as it would change the amount of bias required even if the playback is OK. Another thought - do you record with or without Dolby?

Cheers

Alex

[Nakdoc]

Another possibility is leaking tantalum caps inside the DC-DC convertor module. This module supplies power for most of the audio. I'm working on 2 units and both have bad caps. You would need a rather persistent service person to repair the module (the whole thing is nla), since it involves opening the sealed case.

[Jimmy M]

Hi Jim,

Welcome to Tapeheads!

Most likely this problem is connected to an incorrect biasing - but what is the reason for that would be near impossible to guess without looking at the unit with at least an oscilloscope. It could be oxidised switch or a faulty component, it could be even a head wear as it would change the amount of bias required even if the playback is OK. Another thought - do you record with or without Dolby?

Cheers

Alex

Hi Alex thanks for that! I record with Dolby b and switch it off when listening. I have fiddled with the bias setting by ear in the past but hoped my service engineer had corrected that. well it sounded more like it ought to if that makes sense. I'm not sure if it's relevant but it did go in for service once after it started to play at double speed due to me using a cheap power pack. Then it packed in. Needless to say it did sound amazing in that state but I see that is another story for another thread!
Jim

[A.N.T.]

Another possibility is leaking tantalum caps inside the DC-DC convertor module. This module supplies power for most of the audio. I'm working on 2 units and both have bad caps. You would need a rather persistent service person to repair the module (the whole thing is nla), since it involves opening the sealed case.

Perhaps I should make a replacement module available... *wink* . I have plenty of experience with very small SMPS.

Alex

[A.N.T.]

Hi Alex thanks for that! I record with Dolby b and switch it off when listening. I have fiddled with the bias setting by ear in the past but hoped my service engineer had corrected that. well it sounded more like it ought to if that makes sense. I'm not sure if it's relevant but it did go in for service once after it started to play at double speed due to me using a cheap power pack. Then it packed in. Needless to say it did sound amazing in that state but I see that is another story for another thread!
Jim

Hi Jim,

I have a plan to make a double speed WM-D6C (or maybe TC-D5 ProII) as I record at double speed occasionally. Fast speed on the WM-D6C usually means a dead motor control chip due to an incorrect P/S polarity. A small diode can protect the unit from that problem.

Cheers

Alex

[Jimmy M]

Hi Jim,

I have a plan to make a double speed WM-D6C (or maybe TC-D5 ProII) as I record at double speed occasionally. Fast speed on the WM-D6C usually means a dead motor control chip due to an incorrect P/S polarity. A small diode can protect the unit from that problem.

Cheers

Alex

Wow I would be really interested to know how that turns out! I don't use my D6 for everyday listening anymore, I am just archiving my old tapes right now. I would like to use it for mixing my own music to, I'm sure a double speed D6 would produce a sound with a certain character and a real talking point. When I can get the tape I mix to my pride and joy, a nagra 4. I think I'll start with a process of elimination with my D6 before considering entrusting it to someone for repair.

[bob955i]

Wow I would be really interested to know how that turns out! I don't use my D6 for everyday listening anymore, I am just archiving my old tapes right now. I would like to use it for mixing my own music to, I'm sure a double speed D6 would produce a sound with a certain character and a real talking point. When I can get the tape I mix to my pride and joy, a nagra 4. I think I'll start with a process of elimination with my D6 before considering entrusting it to someone for repair.

Tell me it's a Nagra 4S. *bigthumbup*

[Jimmy M]

Tell me it's a Nagra 4S. *bigthumbup*

Certainly is!

[bob955i]

Certainly is!

Way to go!*bigthumbup*

A 4S is about the only deck I'd willingly make room for and for me anyway is The Holy Grail of RTR tapedom.

Got the QGB adapter?

[Jimmy M]

Way to go!*bigthumbup*

A 4S is about the only deck I'd willingly make room for and for me anyway is The Holy Grail of RTR tapedom.

Got the QGB adapter?

Nah. Not worth it for me, at the moment I just use it to mix a few songs per tape, play em back to check then into the pc at 24 bit for mastering. It is special. Of course I'm occasionally tempted by those reissue albums, I expect they come on 10". There is a record company, you may know them, I forget, who record jazz just with a nagra at half speed with a pair of AKG's straight in, no other preamp. The guy even frowns on any eq being added. Love it!
My wife even loves the Nagra!
Jim

[bob955i]

Nah. Not worth it for me, at the moment I just use it to mix a few songs per tape, play em back to check then into the pc at 24 bit for mastering. It is special. Of course I'm occasionally tempted by those reissue albums, I expect they come on 10". There is a record company, you may know them, I forget, who record jazz just with a nagra at half speed with a pair of AKG's straight in, no other preamp. The guy even frowns on any eq being added. Love it!
My wife even loves the Nagra!
Jim

First Nagras I ever saw in the metal was a pair of either mono 3 or 4 when I went to pick up a Ferrograph 3A/N along with a Vortexion WVA. I'm not surprised your wife loves yours as the two I saw were just utterly exquisite - everything about them oozed quality and top-drawer engineering and if ever a tape recorder could be called jewel like, it would have to be a Nagra. I didn't know the guy had them as he hadn't mentioned them in his ad and by the time I turned up, one was sold, he had decided to keep the other and I just couldn't get him to budge. Can't say I blame him though, as I'd be exactly the same if I was in his position, especially if it was a 4S.

Some day though, some day...

I've got a WM-D6C myself that I recently managed to kill after over 20 years of faultless and careful ownership by using a reversed polarity PSU. Classic Oh sh***t moment. Still waiting to see if the supplier I ordered the CX20084 chip from can actually get it...

[Nakdoc]

Perhaps I should make a replacement module available... *wink* . I have plenty of experience with very small SMPS.

Alex

The module is easy to repair. Most technicians wouldn't dream of opening it up, so I wanted to preempt a "nla part" problem.

[scan80269]

The module is easy to repair. Most technicians wouldn't dream of opening it up, so I wanted to preempt a "nla part" problem.

Interesting! I have one of these opened months ago, and an inductor on the input side has burned out. It has orange, orange, black, silver color rings, so is it a 33uH inductor?