20KHz - 40KHz

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Re: Click & Pop elimination

I've been reading this forum for some time now & Nobody has addressed this prob.

Reason for CD-4 Cartridge OR 40KHz phono cartridge.

Wave Forms! When a click or pop from vinyl happens, the resulting wave form is almost an Exact square wave. (Any freq. + Unlimited Odd harmonics = Square Wave. Do the Vectoring Math!!!)

If you have a phono cartridge that can track 20KHz - 40KHz, you can send that Ultra High Freq. signal to an (analog) processor, that Only see's freq's from 20Khz to 40Khz. That processor can then "Turn OFF" the output of the processor, for the duration of the click/pop.

The Burwen TNE 7000A (Trancient Noise Eliminator) is the most gentle (& therefore most expensive) analog processor. I own 2 of these.

The SAE 5000A (also a Trancient Eliminator), takes a Much More BRUTE FORCE technique to eliminate the clicks & Pops. I also own this processor. IF you take a Razor Blade & carve wagon wheel type spokes on your vinyl, the SAE 5000 can eliminate the Violent Pops. It's FAR easier to for the SAE 5000A to grind your music into UNlistenable Hamburger!!!

I also own the Garard MRM-100, which is also a click/pop eliminator. BUT the output of the Garard is Line Level. It has it's own MM --> Line Level (+ RIAA EQ) output.

The final Question is: Do Any of you Phono Guys process your line level phone signal, to Remove Trancients/Spikes/Clicks/Pops?

MLStrand56
 
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"Almost an exact square wave" is something of an exaggeration. After passing through an RIAA preamp it may be more like a triangular pulse. In both cases an isolated pulse will contain more than just odd-order components. Keeping records clean (and handling them correctly by never never touching the playing surface) will help. Adequate overload margin in the preamp is also important.

I don't use any processing, and find that record clicks are an occasional annoyance - not worth fussing over.
 
Re: Triangular Wave

"Almost an exact square wave" is something of an exaggeration. After passing through an RIAA preamp it may be more like a triangular pulse. In both cases an isolated pulse will contain more than just odd-order components.
No, the math is Exactly = to a Square Wave.

BUT your comment about the Square Wave, becoming Triangular after passing through the Phono EQ has merit. The entire Phone EQ ckt, is Based on freq. I never considered the 20KHz-40KHz freq. wave form AFTER the Phono EQ.

I guess that makes a good case for a 20 - 50KHz phono EQ.

Even if the Click/Pop wave is triangular, the Burwen TNE-7000E makes it go Away.

Does Anybody use signal processing to clean up vinyl clicks/pops?

MLStrand56
 
No, the math is Exactly = to a Square Wave.
No. You only get odd-order components on their own for a continuous square wave. An isolated square wave pulse, like a record click, will contain lots of other frequency components too. Do the Fourier maths, or use a simulator and FFT.

Your original post seems a bit like viral marketing. Please assure us that you have no connection with the makers or vendors of the units you mentioned.
 
"Almost an exact square wave" is something of an exaggeration. After passing through an RIAA preamp it may be more like a triangular pulse. In both cases an isolated pulse will contain more than just odd-order components. Keeping records clean (and handling them correctly by never never touching the playing surface) will help. Adequate overload margin in the preamp is also important.

I don't use any processing, and find that record clicks are an occasional annoyance - not worth fussing over.

FMA has one in their phono pre .....:)

FM ACOUSTICS LTD.   : :   Resolution Series   : :   223   : :    Phono Master
 
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I've noticed that phono stages that have extended HF headroom (and adequate phase margin) seem not to make terribly obnoxious noises when confronted with fairly egregious clicks and pops, it's IMHO those that clip or oscillate when confronted with such a transient that create a major audible issue.

I've been purchasing records both new and used since about 1970 and I have very few recordings IMO that would audibly benefit from such processing, and my concern is almost always about reducing complexity in the signal path rather than increasing it. :D
YMMV of course..
 
I guess that makes a good case for a 20 - 50KHz phono EQ.

Many phono stages contain the "50KHz pole" first popularised by the late, great Allen Wright in the late 80s. This is a resistor in the RIAA which boosts the signal above 20KHz, to compensate for the roll-off introduced by the cutting engineers, to stop their lathe electronics from burning out.

Regards,

Andy
 
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And that might be particularly the case if the ultrasonic performance of the device in question was not particularly good.
FWIW Allen's tube based designs generally had plenty of ultrasonic headroom, but many low voltage solid state designs using global feedback may not.

Perhaps passively equalized tube phono stages of the nature I design and use are less prone to bad behavior when confronted with severe HF transients which is why I feel no compulsion to address the issue further. I do remember feeling somewhat differently before I went over to glowing bottles a quarter century ago.. :eek: :geezer: :D
 
im a bit of a lp nut too.
i find ,as state by DF96, keeping them clean an treating them well saves me from having to do the math or having to add equipment to my chain.

very interesting idea that they have. and im glad that it works for you and you like it.
but no i have never tried it.

do you have allot of noisey lp's?
i have a few but cleaning takes care of most that havent been damaged by poor care.
 
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