VanDerGraaf
pfm Member
At around the same time as The Buggles brought their weirdly-bleak view of the future to our ears, some new and slightly unorthodox-looking amplifiers were emerging from Japan. They would have very much seemed at home sitting in the background of the Video Killed The Radio Star video, on top of Hans Zimmer's keyboard rig. A visual reminder and statement that the 70s were over, with promises of a sleeker, more technological future to come.
Almost 4 decades later, I became aware of these unusual amplifiers.
During the covid shitshow, I finally managed to get hold of one, which, typically, wasn't working.
People would be shocked if they picked up the main portion of the KA-1000 as it is extremely light, due to the largely plastic construction. This was done as Kenwood chased a philosophy of low magnetic interference- hence as little metal as possible. Plastic sides and front with a thick glass panel embossed with logos for the controls hidden behind it.
Some might raise a cynical eyebrow at this point and ask whether it was really about the rather more ignoble concept of cost-cutting. However, Kenwood produced plenty of amplifiers with plenty of solid metal long after this, so I'm inclined to believe the reasons given.
The main reason for the lack of weight, however, is due to the three transformers for the amp being housed in a separate (and very heavy) box with its own small glass front, connected to the main unit by an prodigiously thick umbilical cord. Having opened this box (couldn't resist), you can see the big transformers for the left and right channels, stamped L-01.
This must refer to the "big brother" L-01 amp- very similar concept but on the ultra high-end level. At least I know the transformers are shared!
Freon gas heat pipe for cooling, as was all the rage in the hi-fi world of 1980.
The figures were fairly typical for a big Japanese integrated at the time- 100w/ch at 8Ω, accompanied by an unusual feature that, used correctly, could extend the feedback loop of the amplifier to include the speakers themselves- resulting in a massive damping factor which today's manufacturers like Hegel would be proud of. Kenwoods new futurist oeuvre had a fitting name for this wizardry- Sigma Drive.
Yet more unusual was that despite the conservative manufacturers rating of a 4Ω, independent tests revealed that this odd-looking thing could drive a 2Ω load without expiring in a heap of smoke.
The next step- well, there wasn't much of a next step as we sat locked in our homes. I had to get the amp working.
More to follow....
Almost 4 decades later, I became aware of these unusual amplifiers.
During the covid shitshow, I finally managed to get hold of one, which, typically, wasn't working.
People would be shocked if they picked up the main portion of the KA-1000 as it is extremely light, due to the largely plastic construction. This was done as Kenwood chased a philosophy of low magnetic interference- hence as little metal as possible. Plastic sides and front with a thick glass panel embossed with logos for the controls hidden behind it.
Some might raise a cynical eyebrow at this point and ask whether it was really about the rather more ignoble concept of cost-cutting. However, Kenwood produced plenty of amplifiers with plenty of solid metal long after this, so I'm inclined to believe the reasons given.
The main reason for the lack of weight, however, is due to the three transformers for the amp being housed in a separate (and very heavy) box with its own small glass front, connected to the main unit by an prodigiously thick umbilical cord. Having opened this box (couldn't resist), you can see the big transformers for the left and right channels, stamped L-01.
This must refer to the "big brother" L-01 amp- very similar concept but on the ultra high-end level. At least I know the transformers are shared!
Freon gas heat pipe for cooling, as was all the rage in the hi-fi world of 1980.
The figures were fairly typical for a big Japanese integrated at the time- 100w/ch at 8Ω, accompanied by an unusual feature that, used correctly, could extend the feedback loop of the amplifier to include the speakers themselves- resulting in a massive damping factor which today's manufacturers like Hegel would be proud of. Kenwoods new futurist oeuvre had a fitting name for this wizardry- Sigma Drive.
Yet more unusual was that despite the conservative manufacturers rating of a 4Ω, independent tests revealed that this odd-looking thing could drive a 2Ω load without expiring in a heap of smoke.
The next step- well, there wasn't much of a next step as we sat locked in our homes. I had to get the amp working.
More to follow....