Orange amps were built first by Matamp and then in Orange's own workshops, and the two lines overlap in time while sharing serial formats — so identifying the builder comes before reading the number. The vintage chart covers 1968–1979 and reads model group, panel type, logo and serial format together. The serial is on the metal chassis, never the number stamped into the back of the wooden head shell.
Country
United Kingdom
Active since
1968
Coverage
1969–1979 · 15 serial ranges
Dating tier
Mixed coverage
In the archive
6 series · 7 code systems · 18 models
Years documented
1969–1979
Eras
1968–1971
Matamp years
The first Orange amps were built by Matamp: a prototype run of OR100/OR50 heads in 1968–69 with aluminium chassis and two KT88s, of which the first six went to Fleetwood Mac, and then three-digit serials. Model wording on Matamp builds reads OR50/OR100 or SL100.
1970–1973
Orange's own workshop
ORS 4xxx and 9xxx numbers belong to 1970–71, and OR80/OR120 amps appear as four-digit numbers and then as 80xxx and 120xxx formats through 1971–73, when Orange was building its own chassis.
1973–1979
Year-prefix five-digit series
A five-digit serial whose leading pair is the last two digits of the year runs from 10xxx in 1973 to 16xxx in 1979, with a leading-zero form for 1978 and 1979. Hand-dated inspection tags inside the chassis corroborate the chart.
1980 to today
After the chart
The vintage chart stops at 1979 and later Orange production sits outside it. There is no official dating page for those amps.
What dates this maker
Serial number read from the metal chassis together with model group, panel and logo — the era chart itself is the table.
Builder identification (1968–1975), because Matamp and Orange production share serial formats.
Hand-written inspection tags inside the chassis, the strongest single witness when one is present.
Cabinet serials, where the first digit roughly matches the last digit of the build year.
EIA component codes on speakers, capacitors and transformers, which the Orange guide recommends for a rough build year.
Watch out
The number stamped into the back of the wooden head shell is not the serial number; the serial is on the metal chassis.
The cabinet first-digit rule is a heuristic by its own wording, and cases that do not fit it are documented.
Transitional amps exist: a 1979 Series II Super Bass is documented on a 1974 OR120 chassis carrying an 11xxx serial.
Post-1979 Orange falls outside the vintage chart entirely.
On the metal chassis. The number stamped into the back of the wooden head shell is a different marking and should not be read as the serial.
What do the five digits of a 1970s Orange serial mean?
On the year-prefix series from 1973 to 1979 the leading pair is the last two digits of the year: 10xxx is 1973 and 16xxx is 1979.
How do I tell a Matamp build from an Orange build?
Model wording is the fastest tell: Matamp builds read OR50/OR100 or SL100 where Orange builds read OR80/OR120 or SL120, and transformer brands confirm it.
Is there an official Orange dating page?
No. The vintage chart is a collector publication, checked here against two independent collector pages.