Path: utzoo!attcan!uunet!decwrl!wuarchive!zaphod.mps.ohio-state.edu!uwm.edu!csd4.csd.uwm.edu!info-high-audio-request From: bilver!bill@uunet.UU.NET (Bill Vermillion) Newsgroups: rec.audio.high-end Subject: Re: DBX Message-ID: <6555@uwm.edu> Date: 24 Sep 90 12:51:55 GMT Sender: news@uwm.edu Lines: 58 Approved: tjk@csd4.csd.uwm.edu In article <6537@uwm.edu-> strong@tc.fluke.COM (Norm Strong) writes: ->In article <6354@uwm.edu> gould!infocenter!smatchun@encore.encore.com (Scott Matchunis) writes: ->}I've been reading the discussions about Dolby (initially, whether Ray ->}Dolby's possible hearing impairment might influence his engineering) and ->}how well it works/doesn't work on cassette decks. ->} ->}So I'm curious, what is the consensus of opinion on DBX for home cassette ->}decks? I have it on mine and like it much better than Dolby B. Have never ->}compared it to Dolby C or any of the other noise reduction systems ->}available. ->} ->}Anyone out there in "netland" using DBX on a cassette deck? What do you ->}think of it? -> ->I have dbx. I find it a definite improvement when using cheap Type I ->tape, such as C-120. But I use Dolby C with Type II tapes, mainly because ->I'm concerned with the future availability of dbx equipped decks. -> ->Another problem with dbx is inferior bass response. The quicker the ->aperture response of the encoder, the sooner the bass has to roll off. ->Not much you can do about this. Not a comment on dbx on cassettes, as I have never used that combination, but a comment on dbx in general. We had 48 tracks of dbx encoding at our studio 24 permanently in one room , 16 in another, and 8 tracks that floated between the two studios. A room had a 16/24/32 track machine and B had a 16/24. dbx's compansion/eq routines expect a machine to be reasonably flat. Any anomolies in the rec/pb chain are exagerated. Our 32 track head-stack had a rec/pb bump of almost 2db in the 175-200Hz range, so when doing dbx on a 32 track session, we depressed that band by about 2db during the rec process so that pb was relatively smooth. Otherwise we had about 4db bump at that frequency. We weren't that worried about compatibility as there were very few 32 track 2" analog studios in existance. We were perhaps the third, and at the most the 6th in the world the day we opened our dooors. Number one and two were a Cinecitta (sp) in Rome, and Dieter Dirk's (sp) in (I think) Colgone Germany. These were both Telefunken machines, there was another Telefunken in LA, we had a Steven's. I suspect there were not more than 50 in existance, if that, and Queen's producer had a portable 32. With track width's the same as a 4 track quarter inch, noise reduction was almost a neccesity for 15 ips sessions. As for 32 track 3", I think only the pro-type I saw ever saw any service in the real world. The move to a 22.5 ips speed AND 3" tape effectively put that out of contention. -- Bill Vermillion - UUCP: uunet!tarpit!bilver!bill : bill@bilver.UUCP