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---- Clark Johnsen <[log in to unmask]> wrote: 
> FWIW I pretty much agree with what Tom Fine says...
> EQ can be fixed in the digital domain if it was done incorrectly, but
> results won't be as good as if correct equalization had been used prior to
> digitization.

I wonder in what way the digital de-RIAA would differ from the analog, since both apply eq which alters the amplitude and phase.   Perhaps its a matter of precision of the group delay.  But, in fairness to the pluggos, out there, the filters of digital eq _are_ using the z axis and apply that electrician's imaginary constant, j (root-1), in addition to the other familiar elements of the electrical syntax of analog filtering, such as pi.  Gone also are the days of DSP at mere CD sampling rates and wordlengths.  

Personally, the analog domain holds more appeal sonically and conceptually.   However, I'm willing to accept that double-blind ABX'ing of variously "unmastered" material - as in de-emphasized through divers means - could result in completely wrong choices.  (L:

> Ticks and pops must be removed by hand.

When Masterfonics engineers would transfer from disc to CD, the transfer was often "flat," using proper loading of the cartridge.   The un-deemphasized audio was easier to de-Click by hand, according to our Webboard host, since the clicks  stuck out like a sore thumb, or possibly cactus thorn...  Then the Sonic Studio HD 48 bit de-RIAA could be applied to the deClicked audio with the illusion of increased results.  It's true that the bandwidth is limited in digital audio, but one can get close to vinyl with high sample rate filtering, and the resolution of double-precision 24 and 32 bit audio is capable of ultra-precise error (l;.

> It can be an artistic judgment
> whether they belong in or out, e.g. bows striking music stands. I use
> iZotope RX 2. On really bad disks automatic click reduction can be used on
> a conservative setting to get rid of the worst half of the noises, leaving
> less manual work.  (On the worst recordings it can take an hour's work to
> clean up a minute of music.)  This software can also fake tape dropouts,
> sometimes up to 1/4 second. It can even fake glissando and vibrato that are
> missing, but this doesn't always work correctly.

I tried deClicking my personal copy of All Thing Must Pass.  The task proved endless.  I heartily agree about the problem with taking out too much, since strange forests can be left of the remaining inaccessible trees.  Talking to an eq designer earlier this year, he told me that the problem with capturing vinyl isn't the de-emphasis of the cutting eq.   It's that the pops and clicks are near square waves, in terms of their rise times, and digital can only capture sines.  So, it changes the attack and harmonics of the surface noise and makes it ugly, whereas the same noises on the vinyl are easy to ignore and might even be exciting>?<   Incidentally, he said this is also why digital fails to deliver, musically, even though it does great telephony, since the combined harmonic overtones of a full orchestra during a fortissimo would approach a square wave on an oscilloscope, but the CD can't make that happen.   So, for all its accuracy and quietude, its just a stomp box (LPCM).


Cheers,
     Andrew





> On Tue, Apr 10, 2012 at 8:49 AM, Tom Fine <[log in to unmask]>wrote:
> 
> > Read the article, it was in the ARSC Journal a while back, maybe a year or
> > two. Too technical to summarize here, at least for this non-EE.
> >
> > ----- Original Message ----- From: "Andrew Hamilton" <[log in to unmask]>
> > To: <[log in to unmask]>
> > Sent: Tuesday, April 10, 2012 8:39 AM
> > Subject: Re: [ARSCLIST] Recording_78rpm_records
> >
> >
> >  Gary has also written for ARSC Journal advocating analog playback and EQ
> >>>>> of
> >>>>> grooved media, rather
> >>>>> than "flat playback" and software EQ, and has specified the technical
> >>>>> reasons why analog EQ works
> >>>>> differently from DSP EQ.
> >>>>>
> >>>>
> >>
> >>
> >> What is it about minimum phase digital audio equalization, such as that
> >> found in a de-RIAA or RIAA plugin, that Mr. Galo feels is not up to snuff?
> >>
> >>
> >>
> >>
> >>
> >> Andrew
> >>
> >>