Aleph Power Output Stage & Halcro Error Correction Front End - what about this ??

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1. you are trying to mix two extremes - efficient SE , and error correction
2.that's more issue for Solid State forum ; if you take a good look in recent happenings here at Papaland , everything is going in direction of invoking proper ratio of harmonics in THD spectra , not in killing all THD
 
1. you are trying to mix two extremes - efficient SE , and error correction
2.that's more issue for Solid State forum ; if you take a good look in recent happenings here at Papaland , everything is going in direction of invoking proper ratio of harmonics in THD spectra , not in killing all THD
This I know all.

Single ended Class A mode eliminates most of the higher order and all complex components - thus for such an error correction it is an easy task to reduce all low order THD components from the single ended output stage down to rather immeasurable values.

With help of such an amplifier (i. e. SE output power & Halcro error correction) it is possible, which exactly audible effect is perceived while a listening test in case of completly absense of any THD and in case of the presence from a proper ratio THD, consists of mainly second/third order harmonics.

Perhaps one of the member have already investigate this (much more helpful than the endless debates concerning the sonic character of various amplifiers with completly various topologies and different boundary conditions like various solutions for PS-transformers/rectifiers/caps and GND management/earth wiring).

In the moment I observe two main groups of guys resp. two opposite kind of claims:

1) Good sound is only to achieve, if all THD components (i. e. even low order like second order) are extremly low - at best immeasurable values. In other case the reproduction sounds beautiful and more musical, but less realistic.

2) Good sound is only to achieve, if additional a certain degree of low order THD is present, because otherwise an audible over-analytic impression so as harshness (particularly by hard spoken "S") is perceived as a nuisance.
 
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any news?
Your proposal in Post#1 is interesting. Zen Mod made an excellent point regarding the need for some level of output distortion and balancing its good harmonics to get the great sounding FW amps.
I am under the impression that Aleph is initially created as a current source amp. Maybe ACA is such an example. Its output impedance is ~10 Ohms before loop feedback. It drops to < 5 Ohms after loop feeddback.

If you have the desire to further lower the distortion and output impedance of a current source amp, then one possible approach is to mate it with an "ideal" voltage source amp . This approach is found in the Pass Labs Forum, in the thread which is entitled "Compound Power Amplifiers". It may help test the hypotheses you wish to understand with a minimal diy.
Best regards.
 
Yes; based on the language disclosing the invention. This patent will expire in 2016; simply add 20 years to the date of its filing.
tiefbassuebertr: Please check out the attached from a 1983 article in Audio magazine. I thought the Halcro Patent built on some facets of the Sony amp design.
 

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Funny you should find this being of Sony origin. I thought Bruce Candy picks only on small inventors in his other area of interest. Bruce is a man behind Minelab metal detectors, and recently is under a focus after brutishly treating a fellow hobbyist and inventor over a QED metal detector that is apparently exceeding performance of Minelab's top of the line detectors.
 
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