Serial Numbers

turntables, tonearms, tuners, open-reel & K7 recorders...

Serial Numbers

Postby Axel » Sun Nov 24, 2013 1:48 pm

Serial Numbers

Unlike T-Tags, I didn't delve too much into serial numbers because they are often obscure, coded (by nature) and…
not as fun to track down :)
However, some important periods and breaks can be deducted from (necessarily partial) analysis.

If the Sony or Yamaha s/n systems remained coherent and straightforward since the 1960s, others like Kenwood or Onkyo have
so far remained almost completely mute. Pioneer and Sansui have been well covered elsewhere but I have enough data to
complement the following with some facts for Micro, Technics and Victor. So here's a little I have found regarding S/Ns and,
sometimes, what it means regarding brands' respective histories.

Back in the early 1960s, Denon or Sony had 3- or 4-digit S/Ns stamped on metal plates, with the manufacturing dates - with a mix of Kanji and roman characters. If you find a Sony PT-4 (NHK) a KP-3, or a DenOn 700 open-reel, you'll see items like N° 374 and MAR 1960 on a KP-3 and even the motor type and ID on a PT-4 !

Both Sony and Denon kept such detailed IDs on their broadcast gear (APR and PCM series for Sony, upper DN series for Denon/Columbia) and Matsushita kept basic specs stamped on the s/n plates of the SP-10 but that was a last hurrah. For the others, none of this did last very long and was gone by 1964/65 : demand and supply made S/Ns grow fast, too.

ps. this was mainly written a few years back but is fact-wise still valid.


Fairly simple system where each number is the addition of two notions : geographic destination of the component and the actual s/n.
Said destinations were devised around 1970, when lineups started to be greatly expanded.
As example, early runs of the TA-1055A had 5-digit S/Ns (like "48363") and no market destination prefix ; later ones had the prefix added (and seeing the switch from the Sony IMDK factory to the Sony ASCO outfit). This means that the destination prefix was added gradually throughout lineups, component types and distribution outfits between 1970 and 1973.

This system has remained untouched so far so to have an idea of the total production run of any given item, one has to add the highest spotted numbers of all nine destinations which break down as follows :

#1xx xxx : Asia at large
#2xx xxx : Japan
#3xx xxx : Australia
#4xx xxx : EU multivoltage
#5xx xxx : Europe
#6xx xxx : Great Britain
#7xx xxx : Canada
#8xx xxx : US of A.
#9xx xxx : WW multivoltage

This means that there is a #200 001 TA-F555ES (the first for the JP market), a #500 001 TA-F555ES (the first for the EU market), a #800 001 TA-F555ES (the first for the US market) - etc.

One addition came up during the late 1980s and early 1990 : the European #5xx xxx sometimes saw a "4" added in front of the normal "5" geographic prefix. Probably due to a corporate reshuffling and subsidiaries remixing since "4" means multivoltage, the components can be (re)shipped or (re)grouped anywhere through a different distribution scheme.

The other addition came in 1998, a year before the reunion of all production lines under the single S.EMCS T-tag, or "SOEM", where "M" means Malaysia. This often goes with an added "0" or "2" in front of the geographic prefix but doesn't mean there were #2200105 TA-DR1 produced : it's just a production/distribution thing and the actual s/n remains "Japan" and "105".

Pro & broadcast lineups generally had and still have 5-digit numbers which are not market related and often (but not always) start with a "10".
A TC-880-2, an APR-5000 or an LDP-2000 with "10026" or "10957" serial number is to be taken as such : the highest number is the closest to the actual, worldwide, production run.

Wega, owned in full by Sony after march 1975 inherited from the #5xx xxx system for the components shared within Sony and Wega lineups but kept an in-house system for what didn't come in one way or another from or through Sony : just four numbers !
But for the very last semi in-house series (JPS352, JPS353 etc), production runs of the Wega audio components very rarely went above 3000 units (but for the receivers) so that was sufficient - and they weren't exported either. After the move to Köln, all Wega production was taken over by the #5xx xxx Sony system.

All this being said, this is Sony and this means there are variants… of the variants :)

Variant #1 :
The TC-K61 Limited has a special s/n system which is complex when it could have been simple : if the front "Limited" badge and back serial number bear the same number of the unit ("2002353"), the number shows that a "2" is added inside the normal sequence which should normally be for a JP unit 200 353 and not 200 2 353. This gives the impression that the "limited" number is 2353 -not very "limited" a number- when it really is 353 ! Typical Sony sillyness.

Variant #2 :
The TA-N7(B) was originally and briefly exported in silver guise, therefore named TA-N7 and with silkscreened lettering ; the s/n sticker kept the "ASCO" Japanese T-tag (Sony's Audio Specialty COmpany)… although the silver version was never sold in Japan.
The second batch was the regular "B" in color, therefore named TA-N7B and with stamped lettering. Although the exact same amp (but for the color/lettering) with the same service manual, Sony launched two serial number series. As a result there is a TA-N7 with serial #500 082 and a TA-N7B with the exact same serial… which happens to be my own !

Variant #3 :
Upper-upper-end LD players such as the MDP-999 have S/Ns which don't fit the system outlined above : a Japanese 999 can be #800526 (a JP unit should have a #2 prefix, not 8 which is USA).
The MDP-700 /711 /800 /801 and LDP-900 (all made at Sony Kohda or SOKD) had serial numbers not posted on a back sticker but engraved on a separate plate fixed atop the top of the front plate -luxury- and this was kept for the few export versions as well. The 555 series fits there as well although they were made at Sony Kisarazu... like the MDP-999 which was the ultra version of the MDP-911, itself the upped variant of the MDP-700 - and most MDP-999 have serials sans plate, on a normal back sticker...

All in all, Sony and Luxman are very much alike : uselessly complexified production madness.
That is also why I equally like them :)

Very simple : the number you see is the number you get. No geographical destination, no dating, nothing.

Except for a few world bestsellers like the CA-1000 /2000 or CR-1020 /2020 (export-only) series, Yamaha always had fairly low production runs until 1977/78 : no more than 4 digits for the entire worldwide production run. Still makes for 9999 possible sales - I'm sure many manufacturers today would love to get there !

After that, Yamaha understood selling a few C-1 and FX-1 wasn't really good business and the s/n system was gradually "enlarged" so it could hold 6- or even 8-digit series. This started in late '77 with the X /R /V series (CA-R1, CT-V1 etc) then gradually expanded to other, higher, lineups.
Unlike Sony's ES Review which was published between 1967 and 1997 (!), Yamaha's own corporate magazine (named "Apex") was only published between 1978 and 1981 and, after 1982, the brand went for the tangible gold and it shows in the way its own catalogs were made…

The s/n system was altered in 1987 with the addition of one letter as prefix and two as postfix, with five digits in between and even six later on ; this was applied to the pro/studio gear as well. By that time most of Yamaha's audio manufacturing had been shifted to its own Malaysia factories.

Interesting to note : the CA-800 was made by Yamaha but the CA-800II by Taiheyo K ; the latter has 6-digit serials, whereas the original has the normal (for Yamaha, then) 4-digit. This clearly means Yam' called on an external provider for something it planned to sell a lot of. The early CA-800II just had small "Taiheyo K" stickers added, quickly changed for the regular, full-size sticker replacing entirely "Yamaha" by Taiheyo K - so obvious it screams.
Taiheyo K became a very regular Yamaha supplier for such items until the late 1980s, when Yamaha's audio production in Japan had gradually decreased, the bulk of which was already mostly handled by Yamaha's own factories in Malaysia. Taiheyo K then switched to Sony ;-)
(or was absorbed by /or... it's impossible to know now.)

Simple, if a little opaque on the sides due to the dual Columbia/Denon sourcing, factoring, marketing, distributing.
Until the early 1980s, Denon has a simple system where a recurent "11" means it is Denon per se ; after that, gradually, other recurring 2-digit tags appear such as "15" and "24", the "15" quite probably being the successor of the original "11" (ie. Denon per se, in house, at home).

From this, the 2-digit ID is quite clearly related to the factory/provider/contractor, the rest being series/set/run (first three digits) and s/n (last four or five digits).
After the mid 70s "12" attempt (most of the 255/355 series), this evolution takes place throughout the 1980s, when Denon went, like most, from fairly restricted lineups to gigantic offerings in fifty variants each.

The evolution is obvious for the PRA-2000 series...
1 11 4117 (2000)
1 11 0835 (2000Z)
705 11 00334 (2000ZR)
712 11 00570 (2000ZR)
002 15 00087 (2000RG)
105 15 00455 (2000RG)
505 15 00858 (2000RG)

As well as with other examples with models and T-Tags / origins in parenthesis :
11 0020 (POA-1003)
11 0717 (PMA-700)
11 3075 (PMA-350Z)
11 1643 (PMA-850II)
11 3653 (PMA-630)
11 11076 (PMA-790)
11 51037 (PMA-500V)

12 0341 (PMA-255)

504 24 03025 (PMA-1000G ; TOC JP)
711 15 00722 (PMA-1010D)
109 24 09320 (PMA-390 ; JP)
205 68 00013 (PMA-390 ; Sanwa SS)
312 85 02639 (PMA-390 ; China)
701 76 11510 (PMA-390 II)
704 76 12340 (PMA-390 II)
209 15 57191 (PMA-390 IV)
505 15 71995 (PMA-390 IV)
105 66 59606 (PMA-390SE, China)
907 66 52042 (PMA-390SE, China)
105 66 61160 (DCD-755SE, China)

506 91 00826 (DA-500, Misaki EC)

402 15 00419 (DCD-SA500 ; Denon JP)
203 15 00441 (DVD-A1 ; Denon JP)
302 15 04238 (CDR-W1500 ; Denon JP)
604 15 01395 (PMA-2000 ; Denon JP)
703 15 06784 (PMA-2000 ; Denon JP)
704 73 00258 (PMA-2000 ; T.Denkai JP)
705 73 00523 (PMA-2000 ; T.Denkai JP)
207 33 00437 (DNP-F109 ; China)

706 63 01351 (DP-300F ; China)

703 15 06784 (PMA-2000)
705 73 00523 (PMA-2000 ; T.Denkai)
206 15 04765 (PMA-2000SE)
601 15 02082 (PMA-2000AE)
105 15 03699 (PMA-2000III)
108 15 05037 (PMA-2000III ; T.Denkai)
912 73 00916 (PMA-2000III ; T.Denkai)
305 15 05293 (PMA-2000IV)
307 15 05870 (PMA-2000IV)
504 15 10879 (PMA-2000IV)

Complex, as usual, and with variants to shame any Kafka-esque nightmare !
Whether pre-, during or post-Alpine, Lux serial numbers seem to have always had a prefix code and the actual s/n.

Until 1973, generally, the first four digits make a coded description, the last four the actual s/n.
After 1973, a letter prefix was substituted to the first digit. As I've never seen a lettered prefix above the 12th letter (L), this may describe months :
A = january, B = february ... F = june ... and L = december.
This remained in place between 1973 and late 1983, the period during which LUX was blazing fast and bright throughout the Universe.

During Alpine, the first letter denotes the manufacturing source :
A = Alpine (late 1983...1994)

After Alpine, the first letter denotes the manufacturing source, too :
W = Azden (1993...1998) or
L = Azden (between owerships ; 1998) or
L = Luxman (between owerships ; 1998)
G = Goto DS (1998...)
M = Aimor (1998...)
Y = Yokohama BS (2011...).
F = Fukusima D (PD-171 only).
H = "CH" or "EH" (PD-171A/AL).

All this was "Made in Japan" ; it is only since the IAG buyout that manufacturing was deported to China and "Assembled in Japan".
Goto D.S. "assembles" in Japan was is built in China (the SQ-N100, D-N100 and the recent "neo-classico" series for instance).

Notes :
During Alpine ownership (late 1983-1993/94), Alpine made a separate s/n system for the export items (why make simple when complex is at hand so easily ?) but kept said system somewhat simple : letter "A" as prefix (A for Alpine), device type/code (7072) and serial (0871) : A70720871 (late C-02) or A4702546 (early M-02) A70728597A (late M-02). Sometimes with an "A" added as postfix - don't ask.

Luxman naming is also very Luxman : separated in two. What is "close to home" and "slightly more distant" : close means there is no dash or a space between prefix and number, distant is with dash. Examples :
PD441 vs PD-300
SQ38D vs. SQ-38s
LX38 vs. LX-360
MB3045 vs. MA-88.
Of course, the M-6000 was very close to home… but there's a dash. Perhaps because it was designed by a foreigner. I think it's a matter of "imbued spirit" - I know I have the precise answer to this in my corporate literature but that isn't translated yet.

(some) S/N examples :

1120 0070
1120 2640
1121 2349
1121 3001

D650 1101
H650 1642
K550 0161

(Clearly, the 1120 cannot "mean" "L-309" because there are also L-309 with "1121" as prefix.)

1110 2146
1110 2301
1110 3104T
1110 3413T
1110 4192
1110 6442
1110 8744
1110 9284
G551 0085 (possibly a july 1973 or july 1974 ?)

B650 0126
C650 0296
D710 1943
F650 0954

C890 0853
F890 1214
F990 2682
I890 1525
I890 1599
K990 2806

D890 1025
D890 1081
D890 1206
D990 2436
I890 1582
L890 1764V

C-12 (escapes the month thing - this is LUX allright :)
710 286
802 114

K710 0589
K710 0656

B-12 (all LCJ T-tags)
F910 1723
G810 0574
G910 1769
G910 1772
G910 1787
G910 1782
G910 1823
L710 0185

L-11 (LCJ T-tag)
B910 0892

Later on, before Alpine
C350 3957
C350 4040
F350 4324
G350 4666
L150 1647

Just before and during Alpine, the very beginning of which briefly saw a return to the non-lettered prefix.
5031 1329
5071 1547
B440 1276
B440 1485

C4401 075 (Lux)
F4401 214 (Lux)
H3101 112 (Lux)
L3101 377 (Lux)
5021 0528 (Alpine)
5021 0532 (Alpine)
5031 0878 (Alpine)
A7011 1055 (Alpine)
A7011 1078 (Alpine)

40810 717 (normal Lux s/n and T-tag)
A4401 420 (Alpine s/n but...Lux T-tag)
A4401 421 (bis repetita !)

During Alpine :
A6111 0415A
A7011 0819A

A0101 0756A
A8061 0268A
A8041 0141
A8121 0482A
H9101 0656A (Alpine-EK tag, so late/end run)

Later on, after Alpine : all is AZDEN-made.
W4091 0140
W5061 0576
W5081 0634
W8081 1032D (C-7i)
W8061 1214C (M-7i)

Later on, in-betweens :
L1101 0021 (C-10II Custom ; Azden made bt with an L as prefix)
W8051 0225 (D-7 ; W of Azden prefix but AiMor t-Tag...)
W8011 0361 (D-600s ; W of Azden prefix but AiMor t-Tag...)
W6121 0437A (D-700s ; W of Azden prefix but T.Sound t-Tag...)

Later on, after Azden :
M2061 0145A (AiMor ; M-8f)
M7020 0192A (AiMor ; L509u)
Y9060 1015G (Yokohama BS ; L-550A II)
Y9070 0025 (Yokohama BS ; D-05)
G4070 1024 (Goto DS ; CL-88)
G7100 0701 (Goto DS ; SQ-N100)

Ah. Very complex due to the many ownerships and apparently (or necessary) (or necessarily) savage reorganizations.
Some parts are easy, others... still working on them.
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