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Hi John, This article by Ethan Winer might shed some more light on EQ and phase shift. http://ethanwiner.com/EQPhase.html Rgds Tim. ----- Original Message ----- From: "John Haley" <[log in to unmask]> To: <[log in to unmask]> Sent: Monday, April 16, 2018 10:46 AM Subject: Re: [ARSCLIST] Variable Reluctance Stereo Cartridges was "High Def vinyl?" > Doing the phone EQ with digital de-emphasis does cause phase shifts. To > get it right with certainty, you need to do the phono EQ de-emphasis in > the > analog domain, which is generally done upon playback of the record, before > digitizing. Gary Galo gave a detailed lecture about this topic a couple > of > years ago at the ARSC convention in Pittsburgh. Doing it analog exactly > matches what was done when it was "encoded" (when the emphasis was added > to > the recording). > > How much audible difference it makes, I think, depends somewhat on the > source itself. But if you do it analog, you know you have it right. > > Best, > John > > > > > On Sun, Apr 15, 2018 at 10:39 PM, Tim Gillett > <[log in to unmask]> > wrote: > >> Hi John, >> >> Doesnt analog EQ, by definition, shift phase? Or are you saying digital >> EQ doesnt shift phase? >> >> Rgds >> Tim Gillett >> >> >> ----- Original Message ----- From: "John Haley" <[log in to unmask]> >> To: <[log in to unmask]> >> Sent: Monday, April 16, 2018 10:28 AM >> Subject: Re: [ARSCLIST] Variable Reluctance Stereo Cartridges was "High >> Def vinyl?" >> >> >> Yes, Paul, but after resampling it to get it to the correct speed, you >> have >>> abandoned the analog world which is the best place to apply the >>> phono-EQ's >>> de-emphasis without phase shifting--i.e., it is best to apply the right >>> curve during analog playback, before digitizing. >>> >>> Best, >>> John >>> >>> >>> On Sun, Apr 15, 2018 at 9:51 PM, Paul Stamler <[log in to unmask]> wrote: >>> >>> On 4/15/2018 4:02 PM, John Haley wrote: >>>> >>>> Mickey, >>>>> >>>>> There is a real issue with dubbing 78's (or any other recording) at a >>>>> speed >>>>> other than what it was intended to be played back at. You are >>>>> drastically >>>>> changing the frequencies of the recording when you play it at the >>>>> wrong >>>>> speed, which will totally screw up the intended phono-EQ decoding, >>>>> which >>>>> is >>>>> keyed into the original frequencies. >>>>> >>>>> >>>> [much more good stuff snipped] >>>> >>>> If you dub the disc using a flat preamp with no EQ at 33.33 rpm, you >>>> can >>>> then resample it to an equivalent speed of 78.26, 76.6 or 80 rpm as >>>> needed. >>>> (Audition does his well.) Once it's at the right equivalent speed, you >>>> can >>>> add de-emphasis at the appropriate frequencies. This offers, for >>>> example, a >>>> way to get the good tracking of a Grado 78 cartridge, while minimizing >>>> the >>>> infamous "Grado wobble" -- there will be fewer things to excite it at >>>> 33.33 >>>> rpm than at 78 rpm (or a similarly high speed). >>>> >>>> Peace, >>>> Paul >>>> >>>> --- >>>> This email has been checked for viruses by Avast antivirus software. >>>> https://www.avast.com/antivirus >>>> >>>>