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ELEX serial numbers

Posted under Projects at . Last updated 2024-01-16 00:40.
Tags:ELEX, Hohner, reference, HIP II, K1, K2, Stringvox, K4, String Orchestra (ELEX)

Significantly revised at 2024-01-10 with the discovery of new serial numbers which clarify several points that were speculative earlier.

A list of known ELEX K1, K2, K3, K4 serial numbers (including rebranded models). These seem to come as 2-part numbers; it’s not certain what the parts are, but it seems likely to be batch and serial. (It isn’t week and serial, as it’s continuous across at least four years of production, 1976–1979.)

(For details of the instruments and revisions see here. The rn for revision+number is my addition, not part of the original model numbers.)

No numbers known for a K3 yet.  introduced after the K1r1s began production; it may have been introduced with the K1r2.

Revision 1 K4s had an external power supply and volume pedal, like some older electronic organs. The serial number / rating plates were on this unit rather than the keyboard itself. These are rarely photographed and are sometimes missing. The only known example of a revision 2 K4 (no serial numbers found) is branded String Orchestra and has an internal power supply. K4r3s have a different case but no internal photography has been found.

So long as we regard the parts as separate (or assume a zero-padded second part), the known numbers seem to be in a continuous sequence across the revisions, and between the K1, K2 and K4, and across all brands. The same system seems to have been used for at least some other ELEX instruments at the time [1] but it is not clear whether the other models used the same actual sequence. Unless this point can be clarified (by finding a number collision between models) it will not be possible to use the numbers to estimate production volumes. (The later EK 2 and EK61 had four-digit serial numbers, so are not part of this sequence.)

The serial numbers found in batches 20–31 have a prefixed slash. [2] All numbers known in these batches are two-digit, so it is not yet known how one- or three-digit numbers are treated, if there are any.

With the discovery of another new K2 serial number it has become apparent that the revision sequence I had used earlier is wrong; the earlier revision 1 type is later than the revision 2 type, so I’m reversing that numbering.

Most of the examples found are Hohner-branded. Other brands are noted in the table. Anecdotally, the String Orchestras (both black/silver and wooden) are often said to have been sold by Farfisa.

K1 K2 K3 K4 notes
r23  64
r213 151
r114 191the label is on the PSU/volume unit
r217  73
r217  96
r120 /45ELEX
r126 /15
r127 /57ELEX
r230 /17
r131 /65silvertop String Orchestra r1
r2109 144
r2118  13
r2126  45silvertop String Orchestra r2
r2/3?131  86This is the "VSE Comment K1", not seen; unclear whether an r2 or r3.
r4150  21
r3153  45
r3155  53ELEX. The 5s here are uncertain.
r5163  95
r3167  24
r3170  76The power rating seems to be wrong.
r3173  62ELEX
r3173  97
r6174  99
r3177  25

From which, so far, conclusions are:

Appendix: Power ratings

The power ratings given on the K1 and K2 models vary for unclear reasons.

K1r2s are either 25W or 16W rated; later revisions (only one example of each) seem to be 10W. This may imply some under-the-cover changes in the r2. The power regulator board in r1 seems to be quite different from that in r5 and r6. However, on the basis of the K2 (below) the ratings given may not be reliable.

K1r217 7316W
17 9616W
30 /1716W
109 14425W
K1r4150 2110W
K1r5163 9510W
K1r6174 9910W

Earlier r2s didn’t give a power rating and I haven’t yet seen labels for r1 or r3, but the 12→1 oscillators change was the r3/r4 step.

K2r1s all seem to be 16W. K2r2 plates I’ve seen photographed are mostly 25W but some are 16W. At the time of writing I haven’t seen any interior shots of an r2.

K2r3s may be rated either 16W or 10W but I have concluded that on a K2r3 I’ve been working on, the power rating is simply wrong, as if a 10W rated plate was put on the back just because they’d run out of 25W ones. Its actual power consumption seems to be 22–23W. This implies that none of the power ratings for this model can be trusted, and cannot be used to establish anything about the sequence or circuitry changes.

I haven’t seen any K3 plates with interpretable power ratings. (The one I have seen could be 10, 16, or 18W.) All K4s with visible plates are 14W.

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  1. e.g. 113 153 is a contemporary Hohner organ manufactured by ELEX, the 49R.  
  2. In an earlier revision of this page the interim assumption was that the slashes were digit 1, but it has become clear that this is not the case.  
  3. In an earlier revision of this page this was regarded as uncertain, with the balance of evidence favouring it being revision 2.  

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