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Chuck[_27_] Chuck[_27_] is offline
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Default TV Pictu What Does "Calibration" Mean???

On Wed, 28 Oct 2015 22:06:07 -0700 (PDT), wrote:

"Well - this is a horse of an entirely different color. "


You an AKer ?

Anyway, in response, speakers run 5, 6, 7 dB off, microphones about the same. Amps, tuners, whatever, consider them good within 3 dB. And people are afraid to use tone controls ? Where is that in the Bible ? Where is that in the Constitution ?

What's more, when turned all the way up that bass control is doing what it is supposed to do. Or all the way down. It was endowed by its creator with that ability. It is your free will to use it or abuse it. Like a gun, well at least as far as some woofers are concerned but they are just paranoid...

Bose had no shame in using a permanent EQ. Neither did I. Years ago I had speakers used to have a small woofer and like an 8 or 10 inch passive radiator which I replaced with a four ohm woofer.

It was not good, but using the full range off a Soundcraftsmen ten band EQ I got them to sound good. And when I played a few other things on them I started liking them better and better. Damn that bass was smooth.

The settings were 31 Hz at +max, 62 at 0, 125 Hz at -max (min) and the rest gradually up to the center from there to about the sixth band. It sounded fantastic, but was inefficient as hell. First of all it was 2.3 ohms, poison to at least half of the amps known in existence, or not actually...

The lights dimmed when I cranked these babies up. Eventually they became the rear channels in my quad system. Fed them with a supposedly low power Sansui 771. I scoped it once and don;t remember the reading but it was well over a hundred a channel into that 2.3 ohms. The front was the Marantz 4270 running into speakers I put together. A 12 inch three way system, decent dome tweeters, noting fancy ad did not sound perfect, but I had an EQ for them as well. Separate EQs for front and back. Yup.

Once set, I believe the sound was damn hard to beat. Nobody did back then, at least in the current crowd. And I had it with the Advent five foot silver screen job with the mirror out front, AND MINE WAS CALIBRATED. Someone has just changed all three CRTs but it had another problem nobody could fix. Nobody else that is.

You look at these things and the picture is trapezoidal, the convergence is ****, you can't read the letters sometimes because it is so bad. Not mine. Mine was perfect. Convergence within a raster line width everywhere on the screen. I figured out a little design defect that was keeping the others from having that. It was radiation from one wire to another, polluting one of the waveforms going to the convergence waveform board. It caused an error at the right side and most people just made it overscan, not me. On a five foot diagonal screen my overscan was less than an inch on each side. Now remember how long ago this was. Your TV picture got smaller when your fridge started not long before that.

I wouldn't mind having one of those old sets now. Not that I have anywhere to put it, but if I did...



We had one of the Advents in our living room. One day the video died.
We didn't have a scope at the house and all the parts in the video
circuit checked okay. What we eventually found was that there was a
transistor with over 30v on the collector. It worked perfectly up to
29v, then when this threshold was surpassed, it ceased to amplify.
Hours of pure enertainment.

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