John Curl's Blowtorch preamplifier part II

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Television is now in color? !!! (For the Brits.. colour?)

Actually one of those little bits is that not only do I wire the stadiums or arenas for the in-house TV often I provide the sets. The smart folks used to do a factory direct deal, but then the installation becomes an issue.

Now for those who have never had the joy of calibrating 500 or so units, what can I say no one in their right mind does it. From experience the simplest method is to send out a test signal and use a comparison card. Never seen a commercial kit for this.

My own set is a leftover from an install. Same as the one it replaced. I have neither cable nor internet at home. Video discs and off air are my sources and I think that hints at how much television I care for.

Now one of the perks of the biz is that on site I can see what goes out from the TV truck producing the program, what the off-air signal looks like and what cable does to it. The difference between a live symphonic concert, a good system reproducing it and the perceptually encoded version on Dr. Dre headphones might be a reasonable analogy.
 
My point, but I am sure there must be some way of using the PC+spyder and the TV controls, but its probably horribly laborious.

Monitor or television, buying one with menu-based LUT color calibrations is consistently the best way to get good color, and then if you want the last n'th of balance on your photoshop machine, you use an ICC correction to finish the job off. Yes, you use your spyder/colormunki to get you there. Not sure which TV's have menu-based LUT option, but it's a must for me monitor-wise (which was 7 or so years ago at this point!) Yes, it's a one-time horribly laborious thing.

Remember:
https://xkcd.com/1205/
 
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Now one of the perks of the biz is that on site I can see what goes out from the TV truck producing the program, what the off-air signal looks like and what cable does to it. The difference between a live symphonic concert, a good system reproducing it and the perceptually encoded version on Dr. Dre headphones might be a reasonable analogy.

True story from the late 80s. The BBC were doing a demo of HDTV to a politician. He turned up and whilst the whitecoats were rummaging around he watched a large screen in the lab intently. After a few minutes he turned around and said 'amazing, this is the future' at which point the hosts pointed out that he was looking at a broadcast 625 line baseband feed on a properly calibrated monitor and they were just getting the HD demo running.

Of course back then 16:9 CRTs were too big for the average residence but we were told that in a few years TVs would be 2" thick and hang on the wall. I really did think that was impossible at the time. Which proves that no one should believe my technology predictions!
 
I, too, love TV. I spend most of my evenings with it, and FM radio in the daytime. Still, I don't have the 'best of the best' in TV, just a good HD projection TV. Richard Marsh recently suggested that I go up to 4K. I just can't afford it, but then my hi fi tweeter costs about the same as a 4K TV. '-)
 
Now, the question is investing proportional money to the pleasure we can expect of.
Considering the actual content of TV programs, as well as the quality of musical productions nowadays, I don't care any more with "Hi end" reproduction system, to be honest.
As well as cars, with all the laws on speed limits and radars everywhere.
Some can have other scales of values, like outdoors Status Symbol ;-)
 
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What are-you talking of ? There is no "natural" in modern music. (Jazz, Rock'n roll etc...)

Perhaps a little dogmatic?

Believe it or not, some people play modern music (jazz, rock and roll, etc.) on acoustic instruments and sing with just their God-given voices.

Ever hear about the recordings by many contemporary artists with the word "unplugged" in them? If not, please google!

In other cases electronic instruments are used, but only as simulations of acoustic instruments and with no overrarching PA.

They all use PA systems for live shows, amplifiers, effect boxes etc...).

Yes, widely, but not universally used.

More than this it is amusing that when you do the PA mixing of a live show for a group, you try to be as close as possible to the record, previously made in studio, witch is a pure creation regarding the sound.

Been there, done that too. A pleasing, lifelike sound is not mission impossible.

In fact, if you are trying to give the audience a familiar sound and the studio recording was done with multiple mics, then following the same pattern for the live performance sound has its moments.
 
I meant: NOT AS GOOD as analog tape.

IOW, pretty bad.

It is interesting for me to listen to older CDs (still fairly unmolested by hypercompression and the like) that were obviously made from analog tapes.

Example: Peter Nero - For the Nero-Minded/Young and Warm and Wonderful CD Album

"For the Nero-Minded/Young and Warm and Wonderful CD"

My initial reaction was largely sentimental, and I was impressed with the piano and other acoustic instrument sounds.

As I continued to listen, I suddenly realized that this CD was from the days when analog was all we had, as I owned the two records transcribed onto it as vinyl LPs many decades ago.

There's a sort of a subtle blur, a low level angry growl that is inherent in analog tape, and which we are no longer forced to settle for.

It can be and has been shown with DBTs that one generation of SOTA analog tape imposes audible artifacts, and that many generations of fairly average quality but modern digital does not.
 
I my CFA mosfet I would use them as a drivers with collector current between 13 and 15 mA, no pre-drivers used of course. Now I use BF471/BF472 in that position and I think those a equivalent in THT. With standard drivers as MJE15032/15033 I get much worst result.

Based on the NXP simulation models which have been okay in my experience, the BSR19A and BFR821 have low Early effect and low Cob. It seems the BSR20A was discontinued, oddly enough.

The SMD versions of the 2N5551/5401 are a good candidate for VAS and light driver duty.
 
Based on the NXP simulation models which have been okay in my experience, the BSR19A and BFR821 have low Early effect and low Cob. It seems the BSR20A was discontinued, oddly enough.

The SMD versions of the 2N5551/5401 are a good candidate for VAS and light driver duty.

BF820/821 are better candidates I think.

or BFN26/27
 
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The BF471/472 models are seriously compromised from my experience - I just got very bad sim results. I went through them carefully, but could not find the problems - I ditched them and went with the Fairchild 1381/3503.

The 471/2 family were discontinued many years ago - I think they are only available as NOS.

I used them on my Ovation 250 Amp for the VAS - nice specs.

Just be careful of the models though.
 
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