John Curl's Blowtorch preamplifier part II

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I assumed your favorite source was from natural gas.

Solar works best


I'll second that. I wish this TV show was not so obscure, but an episode of "Adventures in Paradise" was about an audiophile living with his wife off on some pacific island having a new generator delivered by small boat (our hero) so he could again get back to his LP's (ignoring the wife of course). What ensued had me LMAO, this was 1960 mind you.
 
"This room is the best room for listening to music in the United States and one of the two or three best in the world according to Leo Beranek the famous acoustician."
Was ABX testing used?

Nocebo
"In these cases, there is no "real" drug involved, but the actual harmful, unpleasant or undesirable physiological, behavioural, emotional, and/or cognitive consequences of the administration of the inert drug are very real."

rgds
jms
 
Nocebo

...Nocebo..."In these cases, there is no "real" drug involved, but the actual harmful, unpleasant or undesirable physiological, behavioural, emotional, and/or cognitive consequences of the administration of the inert drug are very real."...

Thank you, jms, we had been calling this a "Pessebo" in ignorance of the existence of an actual term. Our choice reflects the propensity of some pessimists to be certain that an (or any) imagined change is for the worse. When doing demos in rooms upstairs at the AES, we ran into these types every year.

Also see: "everything sucks, and then you die." :(

Howard Hoyt
CE - WXYC-FM 89.3
UNC Chapel Hill
www.wxyc.org
1st on the Internet
 
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However, John Meyer once told me that he put a plexiglas port on a Klipsch LaScala horn system and noted the cone movement during a live performance. He said that the cone was very stressed by input under the loudspeaker cutoff.

Very interesting and explains something that puzzled me. Doing measurements of my Klipschorn, I found a surprising amount of sound below the design cut-off (like 37 Hz). Perhaps the radiation resistance the cone is "feeling" gets low, the cone goes into bigger motions, and some output continues below cut-off.
 
Full or empty? An interesting concept, a hall designed to sound best empty.

Beranek didn't say which way. Definitely an issue though because halls can sound audibly quite different under different circumstances. Many halls have adjustable baffles and banners which can also be used to control acoustics.

Beranek has a link to his paper on his web site in which he compares 59 concert halls using 20 measured parameters and the opinions of "golden eared" conductors and other afficionados of live music as to their relative ranking and opinions of each. In the paper he tries to find a correlation between what he measured and the preferences of the golden ears. No individuals were familiar with all of the halls, probably most if not all with only a fraction of them. They are all over the world. The number one correlation was what he calls "BQI" or binaural quality index. This is equal to 1-IACC where IACC is interaural cross correlation. BQI is a measure of the stereophonicity of the sound. The second highest correlation factor was bass response.

Personally I prefer to listen in an empty hall because there is more reverberation. I've admitted that I am a reverb freak and have always loved listening to sound in highly reverberant rooms even if they do at times blur definition. That is one reason why I find the sound of most recordings absolutely dead compared to live music. The best way to hear music in an empty hall is to find a way to get into rehearsals in the main hall. Another is to attend concerts when 24 inches of snow have just fallen on the ground and the concert wasn't cancelled. :)

BTW, Beranek made this comment during his Guggenheim lecture in 2001 at the mechanical engineering department at Georgia Tech. I'm afraid it's been removed from their web site. I must have watched it at least a dozen times. An excellent quick tutorial about concert halls and music.
 
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