Dear Shai, 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. Andrew 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.. > Shai > > 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..." >> >> >> >> Andrew >> >> >> >> >> >> 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+)? >>> Shai >>> >>> 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. >>>> >>>> PT >>>> >>>> -----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 >>>> yourexperience? >>>> >>>> >>