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I'm not sure. Maybe under some circumstances it will be audible but as I 
understand it, generally it wont be.

Even so, I feel that there is  good reason to implement the EQ curve before 
digitising such as avoiding compromise of  the ADC's dynamic range with the 
otherwise very bass light signal straight from the cartridge/preamp. I  feel 
feeding the ADC such a bass weak signal is not ideal, especially since some 
converters I've checked are weakest in their S/N ratio in the bass region.

Tim



----- Original Message ----- 
From: "Gary A. Galo" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Monday, April 16, 2018 11:46 PM
Subject: Re: [ARSCLIST] Variable Reluctance Stereo Cartridges was "High Def 
vinyl?"


The phase shifts inherent in disc recording curves, if uncorrected, 
constitute phase distortion. See the reference I cited by Jensen for the 
difference between phase shift and phase distortion. Then, see the reference 
cited by Lipschitz et al, which demonstrates that phase distortion is 
audible.

Gary

Gary Galo
Audio Engineer Emeritus
The Crane School of Music
SUNY at Potsdam, NY 13676

"Great art presupposes the alert mind of the educated listener."
Arnold Schoenberg

"A true artist doesn't want to be admired, he wants to be believed."
Igor Markevitch

________________________________
From: Association for Recorded Sound Discussion List 
<[log in to unmask]> on behalf of Tim Gillett 
<[log in to unmask]>
Sent: Monday, April 16, 2018 10:02:28 AM
To: [log in to unmask]
Subject: Re: [ARSCLIST] Variable Reluctance Stereo Cartridges was "High Def 
vinyl?"

Hi Gary,

I read your 2010 paper thanks.

The question I was raising, and the linked article, including "Some
experiments with Time" by David Clark, referred  whether in fact we can hear
such phase shifts, as phase shifts.

Rgds
Tim


 ----- Original Message -----
From: "Gary A. Galo" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Monday, April 16, 2018 8:34 PM
Subject: Re: [ARSCLIST] Variable Reluctance Stereo Cartridges was "High Def
vinyl?"


The paper John referred to was published in the spring 2010 issue of the
ARSC Journal. Although the various types of software for applying digital EQ
have changed since that paper was published, the issues I discussed are
still relevant.

Gary

Gary Galo

Audio Engineer Emeritus

The Crane School of Music

SUNY at Potsdam, NY 13676

"Great art presupposes the alert mind of the educated listener."

Arnold Schoenberg

"A true artist doesn't want to be admired, he wants to be believed."

Igor Markevitch



________________________________
From: Association for Recorded Sound Discussion List
<[log in to unmask]> on behalf of Tim Gillett
<[log in to unmask]>
Sent: Monday, April 16, 2018 1:12:59 AM
To: [log in to unmask]
Subject: Re: [ARSCLIST] Variable Reluctance Stereo Cartridges was "High Def
vinyl?"

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
>>>>
>>>>