Previously: ‘Early’ types.
Model Numbers (1977–c.1983)
The year-based number system seems to have been retired in 1981. From c.1977–83 new models have six-digit serial numbers where the first two digits are mostly specific to the model. In some instances (presumably the better-selling models) there are additional number blocks.
The last four digits usually seem to be a separate sequence for each model. This is shown by the existence of duplicates of these four digits between models. Consequently the serials should tell us something about production numbers, but we don’t get a production date.
Mostly the numbers were not separate for different national markets. But there are exceptions. Some of the leading digits do overlap between models, but as yet I haven’t noticed any complete duplicates between models.
It seems that the tuners (WT‑12, GT‑6, Micro-Six) don’t follow the same pattern, as indeed, the WT‑10A didn’t. However, as yet at least, there are no duplicate numbers, so these are probably in the same numberspace. The other overlaps are with the PK‑13 pedalboard and the KR‑55B, and there are other question marks around Korg pedals. Perhaps Korg had a slightly different view of tuners and other ‘accessories’ than of keyboards and other more substantial products.
(See the Appendix below for a quick summary of these numbers.)
| model | intro. year | number type | examples |
|---|---|---|---|
| EM‑570 (powered mixer) next model | 1977 | 11nnnn | |
| SE‑500 (tape echo unit) next model | previous model | 1977 | 12nnnn | |
| MS‑10 [1]
(unitary/semimodular keyboard |
1978 | 13nnnn |
|
| MS‑20
(unitary/semimodular keyboard |
1978 | 14nnnn 439nnn |
(see the MS‑20s page) |
| GT‑6 (electronic guitar tuner) next model | previous model | 1978? | 12nnnn? 14nnnn? 15nnnn? 16nnnn? |
This appears to overlap with the MS‑20s and SQ‑10s, but additional numbers might extend that. [2] I have also (2022-09) seen pictures of a GT‑6 with a handwritten number 32405 but I doubt that’s its original number; it may be an inventory number. (2023-02:) There is also now a Micro-6 with a 14- number. |
| SQ‑10 (step sequencer) next model | previous model | 1978 | 15nnnn |
Early SQ‑10s were made with vinyl-on-chipboard ends; this changed to a plastic moulding based on the MS‑10/MS‑20/VC‑10 ends between 151215 and 151238. (Perhaps around the same time as the MS‑50 came out, which had the moulded ends from the start.)
|
| VC‑10 (polyphonic keyboard vocoder) next model | previous model | 1978 | 16nnnn |
Early VC‑10s misspelled the word RESPONSE as RESPONCE on the front panel. I’m not exactly sure when it was corrected but these images show that it was probably between 160449 and 160469, though 160518 and 160581 have a C as well; which may be down to reaching the bottom of older stock piles. However, 160177 has an S.
|
| MS‑02 (control interface) next model | previous model | 1978 | 17nnnn | |
| MS‑03 (control interface) next model | previous model | 1978 | 18nnnn |
|
| MS‑50 (modular synthesiser) next model | previous model | 1978 | 19nnnn |
Most MS-50s had the description “Synthesizer” on the front panel like the MS-10 and MS-20, but some had “Expander Module” instead. These seem all to have been intended for the North American market.
* “Expander Module”
|
| SE‑300 (tape echo unit) next model | previous model | 1978 | 20nnnn | |
| PS‑3200
(programmable polyphonic semimodular |
1978 | 21nnnn |
|
| WT‑12 (electronic tuner) next model | previous model | 1979? | Not sure what’s going on here. The serial numbers are of the model-based type but mostly overlap with other models; it may be that there’s another unknown 22- model too. [3] No collisions so far. [4] | |
| 20nnnn 21nnnn 22nnnn 23nnnn 26nnnn |
|
||
| Λ / Lambda / ES‑50 (organ-strings keyboard) next model | previous model |
1979? | 23nnnn |
|
| Σ / Sigma / KP‑30 (polyphonic preset synthesiser) next model | previous model |
The Sigma release date is unclear. It appeared in the Korg 1978 general catalogue, which did not contain the Lambda, so it seems likely that it came before the Lambda, but the 6-digit numbers come later in the model sequence. | ||
| 1978? | Some Sigmas have a four-digit number starting 0, which is usually also printed on a label on the top panel. Others have a six-digit number starting 24. It seems possible that the 0nnn group are part of the same sequence, but leaving off the 24-. [5] n.b. several sellers have written that only 1,000 Sigmas were made, but it looks like being at least 3,500 from these results. | ||
| 0nnn |
These were all originally 100V-rated (Japan market).
|
||
| 24nnnn |
All the 24-s are 117V/240V.
|
||
| KR‑55 (beatbox) next model | previous model | 1979 | 25nnnn |
|
| 36nnnn |
|
||
| KR‑33 (beatbox) next model | previous model | 1979 | 26nnnn |
|
| X‑911 (guitar synthesiser module) next model | previous model | 1979 | 27nnnn |
|
| Δ / Delta / DL‑50 (unitary keyboard |
1979 | 28nnnn |
|
| PK‑13 (bass-pedal keyboard) next model | previous model | ? | Some PK‑13s overlap (but don’t collide) in 28s with the Delta. But others are 42-, which is not otherwise occupied as yet. There may be another 42- model? | |
| 28nnnn 42nnnn |
|
||
| SD‑400 (BB delay unit) next model | previous model | 1979? | 29nnnn |
|
| SD‑200 (BB delay unit) next model | previous model | 1979? | 30nnnn |
|
| WT‑3 (Japanese-scale electronic tuner) next model | previous model | ? | 31nnnn? |
|
| CX‑3 [6] (electronic organ) next model | previous model | 1979 | 32nnnn |
|
| Trident (I) / TRD (polyphonic unitary keyboard |
1980 | 33nnnn |
|
| BX‑3 [7] (dual-manual electronic organ) next model | previous model | 1980? | 34nnnn |
|
| LP‑10 (electronic piano) next model | previous model | 1980 | 35nnnn | |
| Mono/Poly / MP‑4 (4-voice unitary keyboard |
1981 | 37nnnn |
|
| 47nnnn |
|
||
| 53 nnnnnn |
These don’t seem to be original Korg number plates; presumably Hagström, the importer’s, plates and numbers? |
||
| PolySix / PS‑6 (6-voice unitary keyboard |
1981 | 38nnnn |
|
| 39nnnn |
|
||
| 46nnnn |
|
||
|
|||
| There seems to be an overlap in the 39s between the PolySix and the KR‑55B. (This may be why there are significantly fewer 39– than 38– PolySixes?) The numbers are a bit clumpy, as if batches of one or the other model were receiving numbers, anything from about 10 to about 1,500 at a time. (These figures may change, but the distribution really doesn’t seem random at this point.) next model | previous model | |||
| KR‑55B (beatbox) next model | previous model | 1982 | 39nnnn |
|
| BPX‑3 (bass synthesiser module) next model | previous model | 1982? | 40nnnn | |
| Trident II / TRD‑2 (polyphonic unitary keyboard |
1982 | 41nnnn | |
| EPS‑1 (electronic piano + string machine) next model | previous model | 1982? | 43nnnn |
|
| Micro-Six / GT‑6J (guitar/bass tuner) next model | previous model |
MuZines has an advert for the Micro-Six from the December 1982 Music UK. So this is likely to be about the right introduction date even if there are earlier number types. | ||
| 1982? | 13nnnn 14nnnn 42nnnn 43nnnn 46nnnn 49nnnn |
Micro-6s have turned up with 13/14nnnn numbers, like some GT‑6s. Implications unknown; possibly they were just using up known unused numbers?
|
|
| SDD‑3000 [8] (rackmount ‘digital’ delay unit) next model | previous model | 1982? | 44nnnn |
|
| KPR‑77 (programmable rhythm machine) next model | previous model | 1982? | 45nnnn |
|
| 49nnnn |
|
||
| Some of these numbers look like the earlier year-based numbers, but they were released later than the number would indicate so I assume they are part of the model-number sequence. This could indicate gaps at 48-, 51- to 59-, 61- to 69- and 73- to 79- where I’ve seen no numbers (also, still no 10). They may be out there, but it looks as though at this point Korg just decided to allocate blocks of 100,000. (Not avoiding older numbers, however; so far one collision is known — Mini Pops 3 and Poly-61 702650 — and there are likely to be others.) next model | previous model | |||
| SP‑80 (electronic piano) next model | previous model | 1982? | 5nnnnn |
|
| SP‑80S (electronic piano with strings voice) next model | previous model | 1982 | 6nnnnn |
|
| Poly‑61
(programmable polyphonic unitary keyboard |
1982 | 7nnnnn |
|
| SAS‑20 (presets keyboard) previous model | 1983 | 8nnnnn |
It looks as though there were more than 10,000 of these made?
|
Based on results to date, it is possible that after the decision in c.1982 to use blocks of 100,000, starting with 5nnnnn, there were no models planned for 46- through 49-, but 46- and 47- were used for additional PolySixes and Mono/Polys but as the last possible 10,000 block, 49- was used as an overflow for any models that required it. In which case it is unsurprising that there seems to be no 48- model.
Next: ‘Just Numbers’.
Appendix: “Model Numbers” Summary
(As found. As noted above, some of these correspondences are a little unclear.)
| number type | models | number type | models | number type | models |
|---|---|---|---|---|---|
| 10nnnn | ? | 25nnnn | KR‑55 | 40nnnn | BPX‑3 |
| 11nnnn | EM‑570 | 26nnnn | KR‑33, WT‑12 | 41nnnn | Trident II |
| 12nnnn | SE‑500, GT‑6 | 27nnnn | X‑911 | 42nnnn | PK‑13, Micro-Six |
| 13nnnn | MS‑10, Micro-Six | 28nnnn | Delta, PK‑13 | 43nnnn | EPS‑1, Micro-Six |
| 14nnnn | MS‑20, GT‑6, Micro-Six | 29nnnn | SD‑400 | 439nnn | MS‑20 |
| 15nnnn | SQ‑10, GT‑6 | 30nnnn | SD‑200 | 44nnnn | SDD‑3000 |
| 16nnnn | VC‑10, GT‑6 | 31nnnn | WT‑3 | 45nnnn | KPR‑77 |
| 17nnnn | MS‑02 | 32nnnn | CX‑3 | 46nnnn | PolySix, Micro-Six |
| 18nnnn | MS‑03 | 33nnnn | Trident | 47nnnn | Mono/Poly |
| 19nnnn | MS‑50 | 34nnnn | BX‑3 | 48nnnn | ? |
| 20nnnn | SE‑300, WT‑12 | 35nnnn | LP‑10 | 49nnnn | KPR‑77, Micro-Six |
| 21nnnn | PS‑3200, WT‑12 | 36nnnn | KR‑55 | 5nnnnn | SP‑80 |
| 22nnnn | WT‑12 | 37nnnn | Mono/Poly | 6nnnnn | SP‑80S |
| 23nnnn | Lambda, WT‑12 | 38nnnn | PolySix | 7nnnnn | Poly‑61 |
| 24nnnn | Sigma | 39nnnn | PolySix, KR‑55B | 8nnnnn | SAS‑20 |
Comment or Question about this page? write
Notes
- The service manual for the MS‑10 states that the noise circuit was changed starting with s/n132828. (This implies that Korg used incrementing serial numbers.) It also indicates that the first MS‑10 was 130000 rather than 130001, which implies that this may have been normal for the “model-number” series. ↖
- The GT‑6 appears in the Korg 1978 brochure with the MS‑20 and MS‑10. In Korg’s interview with Mieda Fumio and Nishijima Hiroaki, they state that it was developed concurrently with the original MS-series models, but I have no specific information regarding order of introduction. I’m placing it between the MS‑20 and SQ‑10 on the basis of serial numbers found to date, but there may be more to come . . . ↖
- PS‑3060 perhaps? ↖
- Possibly, having used up the 22- block, someone decided they weren’t going to sell more than a thousand Stage Echo 300s or PS‑3200s, so they might as well use the spare numbers; but the 23- and 26- numbers are a bit intermingled with the later Lambdas and KR‑33s. ↖
- Rationale: No duplication found yet between the 0nnn and 240nnn, and it’s beginning to look like there may be disproportionately few 240nnns. (Update: As more numbers have accumulated it appears that there are even fewer 242nnns, which brings that into doubt. More examples needed.) ↖
- A digital revision of the CX‑3 was released in 2001, which has a six-digit number type. They are also visually distinct. ↖
- A digital revision of the BX‑3 was released in c.2001. They are visually distinct. No s/ns seen yet. ↖
- A pedal (rather than rack) version of the SDD‑3000 with later-type serial numbers was released in 1984 or later. ↖
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Comments
Another Number
by Marcel on 2024-10-11 07:45
Hi
Just wanted to add another serial number to your collection. I own a Korg Polysix with serial number 388'831. It is a 220V model, which was sold in Switzerland apparently by a store called "muller" (there is a sticker on it from the store). I bought the synth a couple of weeks ago from a musician who used to work for Korg. The synth suffered from the typical battery leakage and because it is still not working properly after cleaning of the board and replacing of the battery, I'm going to do a Kiwisix upgrade on it.
Regards
Marcel
comment?