John Curl's Blowtorch preamplifier part II

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Most people would rather have a switch to defeat the lights..... esp annoying to have flashing lights in a darkened room while listening. All these ideas have been seen by dealers and it is usually the dealers who get and give the feedback and that is what I am telling here. Your arguement isnt with me.... its with dealers.
[ You might note the Japanese and Asia brands have dimming on most everything and off for front panel lights.... they have to do this because of dealer/customer feedback.] -RNM

I don't care. Most people are free to buy in BestBuy dimmed lights. My amps don't clip, they compress peaks. But when they compress they honestly warn about that flashing red lights.

I can't imagine somebody sane listening in the darkness High-end sound on deafening level and complaining about flashing warnings.
 
I can't imagine somebody sane listening in the darkness High-end sound on deafening level and complaining about flashing warnings.
The same look at you in a strange way when you tell him you're running drivers+horns, that you prefer CDs to vinyl, that you use some Op amps in your preamp, that your cables are not silver+teflon+cryogenic, that some class D amps can sound damn good etc...
 
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That's a philosophy I heartily endorse. When I read about phono preamps with 34dB overload margins being required, I wonder what power amplifier and speakers one deploys to support multi-kilowatt transients!

And with proper design, clippers can be produced that have undetectable distortion outside of onset of clipping.

Brad

Phono preamps are a different story, they certainly require high overload margins _before_
the RIAA EQ has taken place (ticks and pops from the record surface). This especially
applies to the first stage (linear amplifier) in the two stage phono amplifiers which
are quite often used nowadays.

The lights on our amp turn red when the amp clips, this at 0.1 THD, as I recall. Anyway, I didn't like seeing the amp clip now and then during loud dynamic passages, and turned it off. I'm glad it has a disable switch.

I do have an amplifier with clip lights I use sometimes at partys, I have never seen
them light up (with vinyl playing DJ´s which tend to crank up the volume when they
play their favourite records).
 
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All personal likes and views are valid to me. Just some are more valid than others when it comes to making money. Then the dealer and consumer, as a whole, matter more what they think over the designer when it comes to what featires they want. Dont get crazy over your ideas and views and likes. Its just marketing. -RNM
 
Each person is allowed their opinion based on their experience and taste.
However, I don't agree with you, Esperado, on a number of things, when it comes to audio design. Horns and 10KW? You never were exposed to high sound levels? What about horn throat distortion? How much, on average, at concert levels? Etc.
 
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Horns and 10KW? You never were exposed to high sound levels? What about horn throat distortion? How much, on average, at concert levels? Etc.
The purpose of PA is to push sound in big halls, for the public can enjoy music every where he can be situated in the room, and horns are certainly the best way to do it with minimal distortion. 10 000 watts where for no clipping, and to can respond positively to any situation, even outdoors concerts. Not to kill public ears. (Apart some hard rock shows :).

When i was referring to horns, in my last posting, it was about my home system. Are-you one of those who believe that all horns are as bad as Altec's Voice of theater ?

I use circular wooden horn, calculated for spherical waves, damn linear. (they look like the Jean-Michel Le Cléac’h's ones, while designed before he published)
Distortion; dynamic and power handling is far better than any cone i know between 1500 and 20 000 hz. Linearity and damping too. Symmetrical filters with impedance compensation, impedance curve is 6ohms, -2 +1 in all the bandwidth, response curve is +-1.5 db.

Voices, on rare well recorded tunes, are so natural that you believe you can touch the singer, drums and piano, my mother was a pianist, are just like in the life, with all the natural and easy dynamic. (You can hear the noise of the piano pedal, feel the hammers on the chords)
The system is composed with a 18 inch JBL in a 500L bass reflex for sub, and two ways for the stereo enclosures. 12" made on request from 40 to 1500hz, and a JBL 2426 16ohm (paired, because half of them had a membrane concentric problem) for the top range. Filters are 24db/oct. Directivity is not a problem in +- 30°

I had spend years to make them evolute, and it is the second best system i've ever heard, (so many different studios monitors or shop listening) reason why i keep them since 2 decades with no desire to change. The first one was the same, with a larger diameter horn and a 15" for the low range, but i was married at this time :)

Of course, some can prefer Quad electrostatics, full range little speakers on flat panels, or 4ways enclosures, i believe we do not listen to the same things.
 
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I use circular wooden horn, calculated for spherical waves, damn linear. (they look like the Jean-Michel Le Cléac’h's ones, while designed before he published) Distortion; dynamic and power handling is far better than any cone i know between 1500 and 20 000 hz. Linearity and damping too. Symmetrical filters with impedance compensation, impedance curve is 6ohms, -2 +1 in all the bandwidth, response curve is +-1.5 db.

The system is composed with a 18 inch JBL in a 500L bass reflex for sub, and two ways for the stereo enclosures. 12" made on request from 40 to 1500hz, and a JBL 2426 16ohm (paired, because half of them had a membrane concentric problem) for the top range. Filters are 24db/oct. Directivity is not a problem in +- 30°

I had spend years to make them evolute, and it is the second best system i've ever heard, 2 decades with no desire to change. The first one was the same, with a larger

Of course, some can prefer Quad electrostatics, full range little speakers on flat panels, or 4ways enclosures, i believe we do not listen to the same things.

Sounds like a really good system. Why not write about that in a speaker forum... how to make the cabinets and cross-overs. etc. Your horn bass would be interesting. My systems require a lot of power in the bass.

[I use two systems at the moment -- a high power, high efficiency system with wave guides on mid and highs. 4 Cerwin Vega 15 inch low distortion, high efficiency, high power bass drivers and will add the two TC-Sounds 18 Inch Ultra 5400 sitting in the garage waiting for me this winter as subs to the 15's. Very flat and low distortion at high spl. Two 900W SS mono-blocks of my design and 3KW digital amp for subs.
My other system is based around the new Quad electrostatics....the TC Sounds will be used for both systems with switchable DSP cross-over. Very flat and low distortion. Stereo SS amp at 250/250W at 8 Ohms of my own design.]

-Richard
 
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Esperado, this is what replaced the GD system, 40 years ago, and I helped design it at the time. It was developed to REMOVE horns, except for the tweeters, to minimize horn throat distortion that was so prevalent in the earlier PA. You are arguing with experts here.
 

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True words- Natural facts.
It is out of topic, but, i am living in a country where money was considered as vulgar when i was young, as opposite to the USA, where money was the center of everything. It was outside of my culture's family to talk, and even think about money.
People where building manufactures when they were passionated an expert in a domain, and tried to build the best innovative products they can. Michelin for tires, Citroen for cars, as examples, with no marketing department and no consumer surveys. They had build manufactures for a century. Life was nice, and full employment, and each year was better than the previous one for living.

The things have changed after the 80s. Money, money everywhere and in all the minds.
Now, products are junk (look at cell phones) with no character, planned obsolescence, corporate bankruptcies faster than than lightning. Food is junk, love is sex, no more solidarity between people, unemployment, so much people living in misery. Technology has taken the science's place, no more creativity in arts, but poor photocopies...
"Natural facts" did-you say ?
 
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yes it sucks big time. More natural facts: Big business run the world today and the quality of life as we knew it is becoming a thing of the past.
I think JC fits your old school model as he lives and breaths for audio/design and to make a living doing what he loves... not to be the riches kid on the block.... but to serve the music.
 
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All personal likes and views are valid to me. Just some are more valid than others when it comes to making money. Then the dealer and consumer, as a whole, matter more what they think over the designer when it comes to what featires they want. Dont get crazy over your ideas and views and likes. Its just marketing. -RNM

Do you mean we all should go to banking business instead of creativity that we like? :)
 
Esperado, this is what replaced the GD system, 40 years ago, and I helped design it at the time. It was developed to REMOVE horns, except for the tweeters, to minimize horn throat distortion that was so prevalent in the earlier PA. You are arguing with experts here.
Are-you talking of the crazy Grateful Dead PA system ?

With such a surface, and such a distance between speakers playing the same sources, the directivity lobes were so incredible than you where able to make your own mixing, simply by moving you head some centimeters in the middle of the hall !!!! Hard to find a point where all instruments could be heard together.
And the out of phase mikes for the singers, to cancel the enclosures behind them; so near of the Larsen point, where not a so good idee for voice quality.
For me the most enormous mistake in the PA history. While the idea was very original.
(I have some experience and knowledge too, despite i do not pretend to be an expert.;-)

To be fear, the expensive idea to do not mix sources, but provide separate amps and enclosures for all of them was brilliant.
 
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Citroen, like the model that you had to go to a mechanic to replace the oil filter? '-)
I learned about French automotive 'engineering' with my 5 year ownership of a Renault Dauphine. Try keeping that car running! I should have purchased a VW, but the Dauphine was so CUTE! Learned to be my own auto mechanic for a number of years, however. Good Experience.
 
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