Serial Numbers and Manufacturing Dates

Harptone Serial  Numbers and Determining Manufacturing Dates

Acoustic guitars

Owners of Harptone, Standel, and Supreme guitars have long debated the meaning and significance of the serial numbers in their guitars and how or whether they can be used to determine the manufacturing dates. The answer is not straightforward. The serial numbers for Harptone-built acoustic guitars follow the general format 2XXX-XX. A review and analysis of known serial numbers along with the characteristics of the various guitars makes it clear that Harptone did not intend to incorporate some kind of date code into them like other manufacturers, such as Gibson. In general the first four numbers index consecutively with no regard or reference to a particular month, day, or year. The suffix, or -XX numbers appear to correlate to models, such as Eagle, Lark, Sultan, etc. There are however, significant milestones that occurred during the manufacturing run of these guitars that can narrow down when guitars were made, these three happened in 1972:

  • Pickguards changed from a rounded, or comma shape to a pointed, dovetail shape
  • The adjustable bridge was replaced with one made from rosewood
  • The serial numbers were “recycled” or restarted back to 2000-XX.

Two other significant reference points:

  • Standel guitars were produced only in 1967 and ‘68, all had rounded pickguards
  • In 1975 the zero fret was eliminated. This was also the last year of Harptone production in New Jersey.

Taking all of this into consideration we can present some guidelines that, in most cases, will give an indication of the manufacture date within a year or two but will not give an exact date.

  • Standel guitars are all 1967 or 1968. Numbers below 2100 are likely 1967, numbers above 2200 likely ‘68 and numbers between 2100 and 2200 could be either/or. It is possible that Harptone guitars with round pickguards were produced during this time, the same numbering guidelines probably apply.
  • Guitars with rounded pickguards are pre 1972, dovetail pickguards are 1972 and after.
  • Guitars with no zero fret were made starting in 1975.

Determining the manufacture date of Harptone guitars with rounded pickguards built between 1969 and 1971, and ones with dovetail pickguards built between 1971 and 1974 is difficult, especially considering that the serial numbers were repeated. It is quite possible that two guitars, one with a rounded pickguard and one with a dovetail could have the same serial number. It does appear that the highest numbers for the two time periods are similar, up to around 2700. 

Harptones with rounded pickguards from 2200 to around 2600 could be 1968 to 1971 and the owner is left to interpolate (educated guess) what year he or she thinks it is depending on the number. Harptones with dovetail pickguards between 2000 and around 2700 are 1972 up to 1975, again using interpolation to guess a particular year.

There does not appear to be any correlation between serial numbers and the various models, the numbers seem to be similar for all.

There does appear to be a correlation between some models and the -XX, or suffix number. Eagles (E-6X or E-12X) have mostly low suffix numbers. Larks (L-6X or L-12X) mostly have numbers in the 20s, like -22 or -26. Known Sultans are all -34. There are many exceptions to this and though this is an interesting observation it is essentially useless because the model of the guitar is obvious from its appearance. These numbers may have had some internal use or meaning within Harptone. 

Electric guitars

Determining the manufacture dates of electric guitars is not as challenging since they were all made from 1967 to 1969 except for any that might have been made by Diamond S. All Standel electrics are either 1967 or 1968. Some Harptone electrics may have been produced in those years or, 1969. An interesting observation, some Harptone electrics, or at least the necks evidently were started as Standels. With the end of Standel production at the end of 1968, the inlaid logos of these guitars were changed from “Standel” to “Harptone” some more obviously than others.

Some Standel guitars have Harptone labels. Whether this indicates an early 1967 guitar where the labels may not have yet been available or a late 1968 guitar where the label supply may have run out is, unfortunately, indeterminate based on the serial numbers of guitars with this anomaly.

Diamond S did produce some electric guitars but it is not clear whether they were for sale or not. There were many parts: bodies, necks, etc. included in the sale of Harptone and some Diamond S employees have stated that these parts (some flawed or with minor defects) were assembled into guitars and given to the workers or otherwise circulated but not sold and did not have labels with serial numbers.