This has been a tremendous amount of information. Much of the component-level discussion is beyond me (for now), but gives me great prompts for doing some research/learning.
It's true that I see the A/B revs of the cs800 frequently conflated with the X. But until recently, I was unaware of the subtle differences between them - only that the X was capable of delivering substantially more current.
It's the ability to drive relatively unfriendly loads that piqued my interest. For example, I've got a couple of acoustic research classic 18 floorstanders. Not particularly efficient, and if my research has revealed anything, it's that the nominal 4ohm rating can dip quite a bit with ARs - giving them their reputation as power-hungry. My main integrated amp is a fine price of gear, but it's rated at 4ohm minimum load, and only at 40% more power than the 8ohm rating. Would a more current-capable amp (like the 800x) be better-able to cope with transients and peak current delivery to speakers like the ARs? My novice thinking was - maybe... But what upgrades might be affected to boost the cs-800x hi-fi bona-fides?
The discussion has been helpful. I suppose the easiest step at this point is to hook it up and give it a listen, but I only just got around to checking the DC offset. At this point, I may check the input caps at the very least before I give it a whirl.
It's true that I see the A/B revs of the cs800 frequently conflated with the X. But until recently, I was unaware of the subtle differences between them - only that the X was capable of delivering substantially more current.
It's the ability to drive relatively unfriendly loads that piqued my interest. For example, I've got a couple of acoustic research classic 18 floorstanders. Not particularly efficient, and if my research has revealed anything, it's that the nominal 4ohm rating can dip quite a bit with ARs - giving them their reputation as power-hungry. My main integrated amp is a fine price of gear, but it's rated at 4ohm minimum load, and only at 40% more power than the 8ohm rating. Would a more current-capable amp (like the 800x) be better-able to cope with transients and peak current delivery to speakers like the ARs? My novice thinking was - maybe... But what upgrades might be affected to boost the cs-800x hi-fi bona-fides?
The discussion has been helpful. I suppose the easiest step at this point is to hook it up and give it a listen, but I only just got around to checking the DC offset. At this point, I may check the input caps at the very least before I give it a whirl.
The 800x is 2 ohm capable, because of the upgrade to MJ15024 outputs and a toroid transformer, which were not available in 1978. If you stick 15024 or 21194 outputs in one of the old A or B versions, they run just fine on 2 ohms too. The use of a triple output stage with 5 parallel transistors means that it is (and always was) inherently capable of 100+ amps of peak current without running out of gain, but limited to about 40A peak for safety (a little less on the earlier versions, and less still into a short circuit). Op amp technology was a little iffy for hi-fi back then too, but now you can get quieter op amps.
Some people have an aversion to op-amp input stage amplifiers. By default, the topology uses a large amount of global NFB. Some are convinced that in itself is evil. Personally I like them, because the critical component matching has been done for you, and the user is more protected from possible faults in the input stage. A standard diff pair running off +/-85 volts could potentially expose the user to dangerous voltages if they short collector-base. And the higher gain front end lets you degenerate the VAS, which is not normally done and offers significant advantages in damping factor when the amp is driven well into clipping. This matters not for hi-if use, but when driving PA subs into overload it is a big deal - remaining clean sounding despite clipping heavily.
Some people have an aversion to op-amp input stage amplifiers. By default, the topology uses a large amount of global NFB. Some are convinced that in itself is evil. Personally I like them, because the critical component matching has been done for you, and the user is more protected from possible faults in the input stage. A standard diff pair running off +/-85 volts could potentially expose the user to dangerous voltages if they short collector-base. And the higher gain front end lets you degenerate the VAS, which is not normally done and offers significant advantages in damping factor when the amp is driven well into clipping. This matters not for hi-if use, but when driving PA subs into overload it is a big deal - remaining clean sounding despite clipping heavily.
They did, almost. A Ford T engine with Frontenac OHV head. (This was the Chevrolets after they sold-out.)
Henry Ford in Barber-Warnock Special Ford Race Car at Indianapolis 500, 1924 - The Henry Ford
1924 Ford Frontenac | conceptcarz.com
1924, while Miller was still refining his ("Offy") engine and chassis.
Frontenac-Ford is different from the all-Frontenacs of a few years before.
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I put up with both the CS-400 and the CS-800 in the many cinemas I serviced over the years. They were not very reliable and in the end, most of them ended up in the garbage can having been replaced by QSC DCA series power amps.