Hi everyone. The serial number on my DD-33 Walkman is 506168. Is it a high number? I ha vev no idea. How high did the serial number on the 33 go up to. So let's see who has the highest serial number. The reason I am asking is could Sony have somehow strengthened the centre cog on their later 33's. I have been using my 33 every few days for years now but I have never used fast forward/rewind or cue/review on my unit. I only used these on my D-C2 AND TC-D3 (D3) when I first bought them and they both developed the centre cog split. I only very occasionally used them on my D-6C'S but not now. I use a separate unit for that purpose. So my question is could there be a connection with using the fast forward/ rewind function that could contribute to the splitting of the centre cog over prolonged use? So post your unit's serial number and see who has the highest one.
Hi Emiel. I think it was in production for approx' 5 years so I'm just interested about how many units were actually produced world wide.
I have a strong impression that the highest serial number does NOT correspond with the number of units produced. Typically, manufacturers would not want the competition to know this information, hence why the serial numbers are usually written in a proprietary format and/or randomized. The serial is usually divided into multiple blocks and cannot be decoded as a whole. Like first 2 digits mean something, the next 3 mean something etc. The vast majority of the DD33s I've seen (serviced) are roughly between 100.000 and 300.000 serial number. Have seen very few below 100.000 or above 300.000. But issue is we don't actually know if all units between let's say 100.000 and 200.000 have been produced. Or simply the serial numbers of units produced between 20th week of 1991 and 10th week of 1992 (it's a random example) have the serial number to be a random number between 100.000 and 200.000. Same could be for lower serial numbers, they may be attributed a random number between 10.000 and 50.000 if they are manufactured between let's say first week of 1991 and 20th week of 1991. Don't remember if it was on the DD33 or another unit, but I have seen serial numbers in the milion range (7 digits). However that does not mean SONY produced a milion of these devices. It can simply mean the first digit (the 1 in this case if it's serial 1.233.124) represents a new batch of revised devices for example. And they put that 1 in the front in order to differentiate from other batches. Given the DD range wasn't exactly the kind of walkman you could buy in all electronics stores (because of the price), the customer base for them was limited in practice. I would be interested to find out more myself about serial numbers, but I think only someone who worked at SONY can clarify the situation.
Valentin. Thanks for that interesting read. Serial numbers I think somehow relate to individual units /batches produced. When we talk about the WM-D6/ WM-D6C units with serial numbers below about 100,000 usually have the point head(early units) and those above 100,000 (later units) will have the different head. Also when I look at the second hand EX, slimline units nearly all the ones I see have a serial number 5,000,000 and above. I have not seen many below that number. So what you say makes sense regarding the application of serial numbers. As you say it would be nice if someone from Sony could clarify this issue.
The serial numbers do relate to batches in some way, it's just to me it's not clear in what way. The SONY WM-D6C pointy head vs 35711 head can be thought from a different perspective: below 100.000 means 5 digits instead of 6. So it might not necessarily correlate with the number 100.000 as they correlate with the fact pointy head ones have 5 digit serial numbers. How many 5-digit serial number D6Cs are out there ? It could be well below 100.000 in practice. We just don't have enough data to draw any conclusion. Given how rare the pointy head ones are, I incline to believe they didn't produce that many of them to begin with. Cause let's think of it this way: let's say they produced 100.000 units with pointy head and 75% of them went to trash. There should still be 25.000 units out there. Even if I were to assume only 0.1% of these would be for sale at any given time, we should still see about 25 of them for sale at any moment. And we don't see that. Have to admit I did not pay attention to the serial numbers of the EX line, but what you say is interesting. Would be interesting to see if there is any pattern in the rest of the digits.
It appears that later on, serial number ranges were also used for other portables like (mini)disc, solid state, etc. I have a few that are also in the 5 million range.
Here's what I have gathered regarding serial numbers on the Sony Walkman WM-D6C: History of the Sony Walkman WM-D6C. Compiled from postings on Stereo2Go and tapeheads forums, as well as eBay listings of units for sale. February 1984: Original Sony Walkman WM-D6C released. Amorphous "pointy" parabolic PA259-3602A head marked "Japan". These had screws on the side. Some say the earliest ones with parabollic head are the most desirable. Brown/green phenolic PC boards 1-611-494-11 with through-hole components. X-3305-830-1 Motor. Yellow indicators for Tape Type and Dolby NR Yellow Roman numerals for Tape Type; Only Sony logo on the leather case. Tape drive mechanism MT-D6C-20. January 1985: Generation 2: Supplement 1 notes Dolby chip change from CX20068 to CX 20218, as well as surrounding component value changes. PCB now -12. Serial # range undetermined. Mid 1986: Generation 3: Change from "pointy" parabolic to rounded head 35711 @ ~serial # 72000. Spring 1988: Change to Dolby sticker color from white (silver) to black ~ serial # 117,000. March 1994: Generation 4: Supplement 2 at ~ serial # 267,201 notes change to double-sided green glass epoxy PCB 1-651-545-11 with SMD components. Muting modules and EQ modules and DC-DC converter are part of the PCB, a lot less wires. Change to 1-541-851-11 motor. April 1996: Service Bulletin 395 issued. The motor was changed from X-3305-830-1 to X-3370-805-1. There are some component changes and the addition of a resistor and capacitor. April 1999: Supplement 3 shows two resistor values were changed to make a French model, to lower the headphones maximum output. June 2001: Generation 5: Supplement 4 shows main PCB changed to 1-651-545-14; motor drive servo circuit redesigned with servo IC CX069A. The servo controller is now a smaller 8 pin IC and is protected which is switched by several other transistors and a MOSFET, to prevent damage. Comparator IC added. Change to Dolby IC #2002176. Rev. 1.1 service manual was issued. Generation 6: Change to permalloy head 35712 in serial #s ~510xxx and above. Marking "amorphous head" on the case is no longer present (date undetermined); however, only later units had the “amorphous head” script removed from the badge on the front of the machine so it cannot be used as a reliable guide to which type is fitted. 2002: WM-D6C production discontinued.
