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Hi, all, As many of you know, John Dyson and I are pursuing software Noise Reduction decoders. I'm presenting on the subject at AES in NYC on October 19th. Come hear Alexey Lukin of iZotope talk about single-ended noise reduction at 11:15 and I'll be outlining the four other ways that were used to optimize signal-to-noise ratio primarily in analog audio tape recording at 11:45. I saw Alexey's presentation in Culpeper the end of June and it's very interesting. In case you're wondering, the four methods were: Equalization, New tape formulations, Multi-track (two tracks per channel) recording, and Companders (the subject of this post). John and I have identified eight NR systems that we are considering turning into software emulations. Currently we have a good version of DA working. I do not use the tradenames in conjunction with the decoders to avoid confusion. Out next step for us is to look into DB, DC, X-I, X-II, and C4. We think we'll have these six operational and available in 2019. The DA decoder (which also involved a learning curve for John and me) has been in the works for about a year. DSpR and DS are much more complex beasts with less documentation and we are considering that for the 2020 time frame, but not guaranteeing anything. With that said, my research has identified a total of 16 systems that were released over time. The additional (with their original release dates) are: Ex-Ko from Hungary (1974) and JVC ANRS (1976) which appear to be close enough to Dolby B to use our to-be-designed DB decoder, so they are not an issue. I have hardware decoders for three consumer systems: Telefunken High-Com (1978), Nakamichi High-Com II (licensed from Telefunken-1979), and Sanyo Super D (1982). In the decade that I have had these hardware decoders, I have never run across tapes recorded with these systems. Let me know if you have any that need decoding. I'd love to do them using the hardware decoders. Two consumer formats that I do not have hardware decoders for are JVC Super ANRS (1978) and Toshiba ADRES (1982). Is there anyone who can decode these and, more importantly, does anyone have tapes encoded with these systems? Finally, in the early days of this, Richard Burwen introduced the Burwen Noise Eliminator in 1971 (same year as DBX). I had one in on evaluation when I worked at ABC Television and we didn't see a need for it. It used a more aggressive compander curve and unknown equalization. While DBX is a 2:1 compander, Burwen was reportedly a 3:1 compander, but there may be a knee in it based on one paper I saw. Since this is the only potentially professional format that I cannot decode either in hardware or software, I was wondering if any archive had any recordings in this format and how they were planning on playing them back. The sad part about NR systems is, in a sense, they hold your recordings hostage. We have suspected and known instances of tapes being commercially released without proper NR system decoding, including one instance where the producer and artist liked the brightness that came with not decoding the Dolby A. Thanks, all, for any input you can provide on or off list. Since John and I are doing this (we hope to be able to sell some packages, to be honest) we want to make certain all archives' needs are met in one way or the other. Cheers, Richard -- Richard L. Hess email: [log in to unmask] Aurora, Ontario, Canada 647 479 2800 http://www.richardhess.com/tape/contact.htm Quality tape transfers -- even from hard-to-play tapes.