Dating hiwatt amplifiers
This attention to detail was also the primary reason why Hiwatt production was limited to only 40 amplifiers per month.
As a result, Hiwatts are much more scarce compared to Marshalls and obviously fewer musicians know about them due to their limited availability.
As a result, both Hiwatts and Marshalls that lack channel-switching are still popular and widely used today.
The Hiwatt DR103 design is also based around the use of four EL-34 power tubes and four 12AX7 preamp tubes.
Not bad whatsoever for an amplifier of this caliber.
There is no better value for a player seeking a hand-built, high quality amplifier using only premium parts, period. Hiwatt amps produced with the high degree of attention to detail and quality were made from the late ’60s (around 1967) through the early 1980s.
Sometime after founder Dave Reeves’ death, and a changing in hands of the company occurred, Hiwatt amps began using more "questionable" construction techniques.
These designs are easy to identify when the chassis is exposed because circuit boards were then used and the tube sockets were also placed onto the circuit board itself rather than being mounted directly to the metal chassis.
I say "questionable" because nobody knows what kind of longevity will be sacrificed when continuous levels of tube heat and vibration are exposed to an amp’s circuit board.
Two independent channels were built into these amps and could be used either one at a time or both together but they could not be switched.