I have read with interest many of the threads on these two amplifiers (primarily the KX-200), and the various modification efforts to restore them. The closest I've ever come to owning one was decades ago when I received a KX-200 that was so mangled as to be nearly unidentifiable. That ultimately ended up in the thread I posted here:
http://www.audiokarma.org/forums/showthread.php?t=553403
But recently, I had one here for evaluation that turned up a number of interesting observations. With the recent efforts of tube-a-lou and others to unravel the mysteries of this amplifier, I thought I would share what I learned from that process.
GENERAL: These amplifiers include the biggest and best 7591 iron Fisher ever produced, being identical with that used in the X-202B and likely even the X-202C as well, although I have never had a C version of that amplifier here to verify this. The X-200 also almost surely represents the end of Fisher's production of the fabled 200 series, as identified by three basic observations:
1. The X-200 is a scaled down version of the X-202C, which itself is a VERY scaled down version of the X-202B. With the introduction of the C, the active feedback tone controls are gone, as well as the remote control option, which allowed the tube count to be reduced by two. The indicator lights are gone, as are various EQ settings, the dual tapped volume control, and other circuit details. All of this down scaling carries over into the X-200 as well, with these further reductions noted of that model:
2. With the introduction of the X-200, Fisher finally gave up the ghost on its SpaceXpander feature: Gone are the Reverb In/Out jacks! Good riddance!
3. Also with the X-200, the permanent LF filter I have mentioned so many times is gone: With newer changers having so much less rumble than the older ones, and heavy use of cassettes in play at the time, the filter became an anachronism. In fact, even the switchable LF filter itself disappeared on the scaled down X-200.
It would be natural that the KX-200 would already be a simplified version of Fisher built designs, to keep build issues by home constructors to a minimum. So in essence then, the Fisher built 200 series came in for a soft landing at the KX-200 level. The on-board bias meter of the KX-200 (to simplify the process of setting those controls for home constructors) simply became the final new feature of Fisher built 200 series amplifiers. As a result, these amplifiers are in fact so close as to certainly be cousins, and by all appearances, even kissing cousins. But there are some significant differences that set these two amplifiers apart. In terms of end goals, the X-200 might be considered to be a refined version of the KX-200. After all, the final Fisher built 200 series amplifier can't be outdone by a home built kit!! Undoubtedly however, they were both an effort to bring the whole 200 series of amplifiers (kit and manufacturer produced) and its inventory to a close, with the SS revolution that was upon them.
The detail differences will follow in the next installment.
Dave
http://www.audiokarma.org/forums/showthread.php?t=553403
But recently, I had one here for evaluation that turned up a number of interesting observations. With the recent efforts of tube-a-lou and others to unravel the mysteries of this amplifier, I thought I would share what I learned from that process.
GENERAL: These amplifiers include the biggest and best 7591 iron Fisher ever produced, being identical with that used in the X-202B and likely even the X-202C as well, although I have never had a C version of that amplifier here to verify this. The X-200 also almost surely represents the end of Fisher's production of the fabled 200 series, as identified by three basic observations:
1. The X-200 is a scaled down version of the X-202C, which itself is a VERY scaled down version of the X-202B. With the introduction of the C, the active feedback tone controls are gone, as well as the remote control option, which allowed the tube count to be reduced by two. The indicator lights are gone, as are various EQ settings, the dual tapped volume control, and other circuit details. All of this down scaling carries over into the X-200 as well, with these further reductions noted of that model:
2. With the introduction of the X-200, Fisher finally gave up the ghost on its SpaceXpander feature: Gone are the Reverb In/Out jacks! Good riddance!
3. Also with the X-200, the permanent LF filter I have mentioned so many times is gone: With newer changers having so much less rumble than the older ones, and heavy use of cassettes in play at the time, the filter became an anachronism. In fact, even the switchable LF filter itself disappeared on the scaled down X-200.
It would be natural that the KX-200 would already be a simplified version of Fisher built designs, to keep build issues by home constructors to a minimum. So in essence then, the Fisher built 200 series came in for a soft landing at the KX-200 level. The on-board bias meter of the KX-200 (to simplify the process of setting those controls for home constructors) simply became the final new feature of Fisher built 200 series amplifiers. As a result, these amplifiers are in fact so close as to certainly be cousins, and by all appearances, even kissing cousins. But there are some significant differences that set these two amplifiers apart. In terms of end goals, the X-200 might be considered to be a refined version of the KX-200. After all, the final Fisher built 200 series amplifier can't be outdone by a home built kit!! Undoubtedly however, they were both an effort to bring the whole 200 series of amplifiers (kit and manufacturer produced) and its inventory to a close, with the SS revolution that was upon them.
The detail differences will follow in the next installment.
Dave
