I agree with Rob about the 1/2 sample error.  1 sample at 44.1K is clearly
audible.  1/2 sample, not as much, but still audible.

Does F1 work such that there is a 1/2 sample delay upon A/D, and another
one, but in the other channel, upon D/A, such that the delay cancels in the
analog domain (A-A)?  If that is true, then only the digital output has the
delay, and analog transfers are correct as-is.

Ellis Burman
www.audiomechanics.com

On Fri, Dec 12, 2014 at 5:08 AM, Rob Poretti - Cube-Tec <
[log in to unmask]> wrote:
>
> Hi Mathew,
>
> Below is a link to an F1 manual that illustrates the differences between
> the
> 14-bit and 16-bit formats:
>
> http://www.manualslib.com/manual/466194/Sony-Pcm-F1.html?page=26#manual
>
> As you can see, the 16-bit format has one error correction word: "P" -
> while
> the 14-bit has tow "P" & "Q"
>
> Earlier in the manual, they talk about the fact that a 16 horizontal line
> burst-error can be accommodated in 16-bit - and 32 H lines in  14-bit.
>
> In terms of correcting channel delay - IMHO:  yes!
>
> (Ask any mastering engineer.)
>
> Cheers!
>
>
> _/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/
> _/
> Rob Poretti - Sales Engineer - Archiving
> Cube-Tec North America LLC
> Vox.905.827.0741  Fax.905.901.9996  Cel.905.510.6785
>
> _/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/
> _/
>
>
> -----Original Message-----
> From: Association for Recorded Sound Discussion List
> [mailto:[log in to unmask]] On Behalf Of Matthew Sohn
> Sent: December 12, 2014 12:19 AM
> To: [log in to unmask]
> Subject: Re: [ARSCLIST] Sony 601-esd pcm audiio processor decoder
>
> John, thank you for your detailed answer. My few experiences with F-1 tapes
> have been nightmarish. Everything is fine, until you hit that one spot
> where
> it just won't track..I applied the skew method. twist the knob left or
> right
> until the lights look good, remember where you started, and do it again for
> real. When it works, it sounds great, when it doesn't... Ugh..
> -Matt Sohn
>
>
> On Thursday, December 11, 2014 10:10 PM, John Gledhill <[log in to unmask]>
> wrote:
>
>
>
> Tom -
> o    The tape are recorded in the 14 bit mode with TOSHIBA DX-900. They
> actually have FM tracks of the same material
> o    I am capturing both the FM and PCM
>
> To David Glasser
> o        I understand re the sample rate.
> o      live performance recordings - 6 hours per tape
>
> I have the 14 bit recovery working well with the EP tapes and have a solid
> right green on (or flashing) MOST of the time.
> I just wanted to know the significance of the LEDs
>
> I actually record a new tape through the coax in from a CD player to the
> 601-esd (16 bit) , and then played the tape back and captured through spdif
> to compare the waveforms. I think the the 601 saturates slightly before
> 0x7ffff (around 0x7fef) but the lower values were a bit for bit match.
>
> To Rob Poretti
> o I agree re the 14 bit versus the 16 bit - if  the 601-esd does not like
> the VCR then more error correction will win.
> o However, from watching the screen it is no 1 party bit versus two parity
> bits.
> I think all of the stuff on the right hand side of the screen is error
> correction data. Each line has 3 word pairs and a huge pile of ECC .
> Roughly 3 * 15.75 minus the time lost during the vertical will give you the
> 44.056 This is also confirmed by the fact I can pop up the on-screen
> diiplay
> from the VCR and mot hear any errors,. Like a CD the ECC is spread over
> tape
> space = time to work around dropouts
>
> Is it  important to correct for a 1/2 sample offset. Is this not the same
> as
> moving one speaker in a stereo pair 3mm  further back.
>
> Slightly interesting aside.
> While doing my experimenting for this I tried feeding the video from a vcr
> through a time base corrector to clean it up before going to the 601-esd.
> Video looked much more stable on the screen but the 601-esd did not like
> this arrangement and the tracking bar stayed on the left.
> Perhaps it was the digital re-sampling in the TBC that cause this result.
>
>
> Anyways - I am getting very clean audio back from the ep tapes and wanted
> to
> know about the lights.
>
> I might guess that the guy who designed the LSI to do the decoding put the
> logic outputs there for his own diagnostic purposes and a bright marketing
> guy said "we have left oer LEDs - lets use em" with no one really writing
> down what they meant.
>
>
>
>
>
> On 12/11/2014 7:44 PM, Tom Fine wrote:
> > Hi John:
> >
> > My experience is that NO F1 decoder works well with 16-bit recordings
> > made at EP speed. I also think that later VHS machines with
> > auto-tracking may not align best for F1 recovery because they were
> > designed to also take into account VHS-HIFI signal. A
> > professional-quality VHS deck, even a late-era VHS-HIFI deck, will
> > have a tracking control, but the consumer models lost the tracking
> > control shortly after VHS-HIFI was developed.
> >
> > I'm curious, what sort of material are you working with and how many
> > tapes?
> >
> > -- Tom Fine
> >
> > ----- Original Message ----- From: "John Gledhill" <[log in to unmask]>
> > To: <[log in to unmask]>
> > Sent: Thursday, December 11, 2014 4:45 PM
> > Subject: [ARSCLIST] Sony 601-esd pcm audiio processor decoder
> >
> >
> >> I am recovering sony F1 type audio (PCM and ECC in the video image)
> >> from some VHS tapes (ep speed 6 hr per tape)  - it was actually
> >> recorded with a Toshiba version.
> >> I have the manual for the Sony 601-esd and I think is says the boobie
> >> lights (Red, FlashRed, FlashGreen, FlashGreen, SteadyGreen) is a
> >> logical procession from poor signal to good signal.
> >> Additionally there is a tracking indicator (bar graph moving to the
> >> right)
> >>
> >> I can see from the schematic the LED's are driven from the decoding
> >> logic (didn't really need a schematic for that one).
> >>
> >> However, I an not find out at which point errors are still being
> >> corrected (apparently a few red flashes are fine) and at what point I
> >> can not count on the data.
> >> I am recovering through the spdif -> PC.
> >>
> >> I am hoping there there is a audio archivists list with somebody who
> >> used these 30 years ago and thought to ask Sony exactly what was
> >> being measured with the lights.
> >>
> >> P.S. I found the Sony 601-esd encoder/decoder is not a good match
> >> with most later model VCR's and ep tapes. (the data on the back of a
> >> VCR switch disappeared years ago).
> >>
> >> --
> >> John Gledhill
> >> BIT WORKS Inc.
> >> 905 881 2733
> >> [log in to unmask]
>
> >>
> >>
> >
>
> --
> John Gledhill
> BIT WORKS Inc.
> 905 881 2733
> [log in to unmask]
>


-- 
Ellis
[log in to unmask]
818-846-5525