As I wrote in your quoted response, below, there are other
signals besides bias that the PP can lock to. They mention "logic
control" signals. I suspect there are other ghosts they could bust.
The ATR is only bias-free while reproducing. But when
recording, it should be present, at 432 kHz - almost as high as the
Dave Hill Aria bias. Even if you recorded at 30 ips and then, on
playback, select 3.75 ips and then also vari-speed the oscillator to
50% of that, the 432 kHz bias signal would still be at 27 kHz. Did
you remember to digitize at 2x F/s? Otherwise, it would have been
filtered out by the ADC.
Please audition the samples on the PP website. They made a believer
out of me. There's a Waves plugin to inject wow and flutter into a
digital recording. The PP would not be able to undo this since it
is simulated and does not contain a veiled clock.
On Apr 29, 2010, at 5:53 AM, Shai Drori wrote:
> I can see that working with 160 or even 200 (you can hear it if you
> slow down the tape enough), but the ATR is bias free, at least on
> tapes I made so far. The system is interesting though. How does it
> monitor to see that the original bias did not drift while
> recording? This would make you track the wrong frequency..
> On 4/29/2010 10:24 AM, Andrew Hamilton wrote:
>> There are other forensic time stamp signals besides bias which
>> would allow for an ATR-100-recorded tape to be de-fluttered by the
>> PP DSP. However, even though a tape may be played back by the
>> Airshow ATR-100, it's entirely possible that the tape was recorded
>> elsewhere by a different machine (having a much lower bias f). I
>> believe that Airshow are offering this service with PP for already-
>> existing analog tapes, rather than for creative layback transfers.
>> David Glasser is chief engineer at Airshow and he has mastered a
>> huge amount of audiophile CDs, DVDs, and SACDs. Great ear; great
>> rooms; great gear.
>> From the PP website:
>> "software algorithm, developed with researchers at Cambridge
>> University in England, which identifies a steady-state ultrasonic
>> reference tone (such as tape bias or logic control) embedded
>> within the original analog signal and then performs continuous
>> high-resolution pitch correction in order to keep the reference
>> tone at a fixed frequency..."
>> On Apr 29, 2010, at 4:15 AM, Shai Drori wrote:
>>> My experience with the ATR is just the opposite. I have tested
>>> various transport and some tapes were handled only by the ATR.
>>> Does the system figure out bias frequency automatically. What
>>> does it do with tapes recorded on the atr where the frequency is
>>> so high it doesn't show up on playback (400kHz+)?
>>> On 4/29/2010 8:54 AM, Paul G Turney wrote:
>>>> Well they only use ATR 102 machines which are notoriously rough
>>>> tape handlers....
>>>> They use software to track and maintain a bias frequency so that
>>>> any speed anomolies are and wow and flutter are reduced by
>>>> maintaining perfect pitch with this tone.
>>>> Not worked with Airshow mastering.
>>>> It appears to be a monopoly on the software so Airshow would be
>>>> subbing the work out to PP.
>>>> -----Original Message-----
>>>> From: Chandra Lynn [mailto:[log in to unmask]]
>>>> Sent: Thursday, April 29, 2010 02:12 AM
>>>> To: [log in to unmask]
>>>> Subject: [ARSCLIST] Airshow Mastering& Plangent Processes
>>>> I noticed some earlier postings about Plangent Processes. It
>>>> eliminates wow,flutter and speed aberrations from analog
>>>> masters. They are now working withAirshow Mastering to offer
>>>> optimized tape transfers. The announcement is onAirshow¹s site
>>>> at http://www.airshowmastering.com/plangent.htmlHave any of you
>>>> worked with Airshow or Plangent? If so, what has been