John Curl's Blowtorch preamplifier part II

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You have to match SET toob coloration , with speaker coloration , then speaker wire/ interconnect EQing and then blamo ...!!!!

Fsntastic SET sound , unmatched when you catch the sums ..... :drink:
To me it a more natural midrange and more realistic balance from mid on up . A lot of system have a too detailed presentation caused by very close mic placement . Cymbals have less bit but still have that decay and shimmer at 10 feet . I may hazard a guess that the IM , transient, and odd order distortion are less with SET . Total HD may be more but is of a spectral nature that is less recognized by people than by machines. The peak are less compressed then what the ftc would rate the amps . SET produce a wave form that the ear and brain think is natural . Test equipment see the flaws that are filtered out by the brain . Thus we test for thing that do not correlate high enough to the way we think we hear. But this has been a matter of common debate since at least 1939.
 
To me it a more natural midrange and more realistic balance from mid on up . A lot of system have a too detailed presentation caused by very close mic placement . Cymbals have less bit but still have that decay and shimmer at 10 feet . I may hazard a guess that the IM , transient, and odd order distortion are less with SET . Total HD may be more but is of a spectral nature that is less recognized by people than by machines. The peak are less compressed then what the ftc would rate the amps . SET produce a wave form that the ear and brain think is natural . Test equipment see the flaws that are filtered out by the brain
Have never played with valve gear, but solid state is certainly capable of it; why it doesn't happen more often is because "that's good enough" engineering, ain't. SET for a combination of reasons is 'naturally' resistant to those distortion artifacts that particularly irritate and fatigue the ear, for solid state someone has to work on eliminating those issues - and of course most times no-one does ... :)
 
Have never played with valve gear, but solid state is certainly capable of it; why it doesn't happen more often is because "that's good enough" engineering, ain't. SET for a combination of reasons is 'naturally' resistant to those distortion artifacts that particularly irritate and fatigue the ear, for solid state someone has to work on eliminating those issues - and of course most times no-one does ... :)
They are two different types of devices. Tubes are only single ended while SS has both n ans p devices that are similar but not exactly match need a much better engineer to design with and make sound great. Tubes also have about a 50 year head start on design early SS was an adaptation of tube design . Tubes had audio as a major driving force in their sales radio was about sound then it was a big part of TV. SS had other very profitable directions computers digital ETC.
 
A good argument can be made that an amplifier's performance at 70 or 80 dB SPL, and below, is what really matters, and that even an ordinary valve amplifier performs very well there with conventional speakers. They also normally run hot enough to be in class A at least up to there, so are monotonic and free of crossover distortion.

An SET with adequate (at least 20DB) headroom is just a brute force approach to monotonicity and complete freedom from crossover distortion. Linearity with the 50 watters (type 211 and type 845) properly loaded is quite good. Drivers are a challenge, but not for a dedicated homebrewer. Folks love to poke fun based on stereotypes, but it ain't necessarily so.

All good fortune,
Chris
 
A good argument can be made that an amplifier's performance at 70 or 80 dB SPL, and below, is what really matters, and that even an ordinary valve amplifier performs very well there with conventional speakers. They also normally run hot enough to be in class A at least up to there, so are monotonic and free of crossover distortion.
And I would go along with this - there are all sorts of considerations. Where SS has a major advantage is that it is fairly straightforward and cost effective to get a design to deliver significant power into modern, less efficient speakers; trouble is, quite often the subjective quality is somewhat compromised when doing so.

The end goal is to get a system to both deliver the 'naturalness' being discussed here, and be capable of PA, horn system type dynamics when required by the material - convincing reproduction, IOW. This is most certainly achievable, and very impressive it is too when it all comes together - a good inspirational target ...
 
Looks good :)
 

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