Were those JBL amps from the 60s and 70s any good?
Since this new SA750 has physical toggle switches, does it mean no remote control? I guess retro means retro.
They are excellent. At the time, they were at the threshold of test equipment in that era BEFORE applying negative feedback. It was the Benchmark of its era.
The 60s and 70s JBLs were made before being acquired by Harman. The amplifiers were discontinued once Harman acquired them.
From high level inputs :
±0.75 dB (20 - 20,000 cps); ±1.5 dB (10 - 130,000 cps)
Power amplifier only (measured at test point provided) :
±0.25 dB (20 - 20,000 cps); ±1.5 dB (3 - 200,000 cps)
The pre amp is noisy by today’s standards but if you use the internal test point with even a Topping D50s, it is very quiet. The amp doesn’t have a lot of power by today’s standards either. On ebay, the SA600 goes for 3k or higher depending on the condition.