Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site watcgl.UUCP Path: utzoo!watmath!watcgl!dmmartindale From: dmmartindale@watcgl.UUCP (Dave Martindale) Newsgroups: net.audio Subject: Re: Medium priced cassette decks Message-ID: <2215@watcgl.UUCP> Date: Fri, 9-Mar-84 00:58:00 EST Article-I.D.: watcgl.2215 Posted: Fri Mar 9 00:58:00 1984 Date-Received: Fri, 9-Mar-84 06:51:46 EST References: <6063@decwrl.UUCP> Organization: U of Waterloo, Ontario Lines: 26 I have a Harman-Kardon HK200XM tape deck; it has bias adjust and Dolby HX. I regard bias adjust as a feature useful only in emergencies. To properly adjust a deck for a particular tape requires setting bias, equalization, and record level. Front-panel bias adjust lets you match the bias to the tape by ear, but you can't get the others right so you won't get the highest quality results. For ordinary use, pick a tape, get you deck adjusted for it, and then use nothing else (actually you can pick 1 metal tape, 1 chrome, and 1 normal). Dolby HX: Well, I THINK I can hear a more open high end with it switched on, but I might just be fooling myself. HX works by reducing the bias level when the recorded signal level is high, allowing higher levels to be recorded without saturation. But this changes the frequency response, requiring a variable equalizer whose equalization changes track the bias level changes. It does have two bad side effects: On music with transients which are considerably above the level of the background, I think I can hear funny things added to the sound as the equalizer comes in and out - nothing I can hear directly, but it doesn't sound quite like the original. And on high input levels, the bias level is reduced to the point where the erase head isn't completely erasing the old material. If you bulk-erase you cassettes before recording on them (a good idea) this doesn't matter, but watch out for it! Basically, it's a good idea (higher overload levels, lower distortion at low levels since the bias current is increased above "normal") that may have flaws in implementation. Make a recording with a highly-dynamic piece of music on a sample deck with HX in and out, and listen for yourself. My deck's "funny noises" may not be typical.