hi, i have a couple of broken cassette decks. one with dbx, one with hx pro. was wanting to experiment with tapping into both the dbx and hx pro circuits (in/out), making them independent processing units. i would like to use these on other tape based recorders that don't have them, but could, hopefully, benefit from using their noise reduction/ headroom extension.
i am not a fully knowledgable tech. i can solder and diagnose/ locate minor things, and can repair/ replace parts very well with direction. my ideas exceed my education. mainly, if someone points to something or says "this does that, and here's what you need to do..", i can do it. i don't necessarily know why, but am learning.
i'm really wanting to turn this into a useable project. could someone with specific technical knowledge let me know (before i tear into my cassette decks) if it is technically possible to tap into the hx pro/ dbx circuits (through rewiring, ect). i'd like to be able to go into stereo rca/quarter inch inputs, through the hx pro/ dbx circuit processing, then out through rca/ quarter inch outs to a separate tape recorder.
with hx pro, if i'm not mistaken, there is a bias adjustment signal applied to the tapehead to allow for less high end distortion. would this change things with the wiring? in other words, would the bias adjustment signal not be able to transfer through rca/ quarter inch jacks, but rather have to be hard wired to the circuit of the separate tape recorder, going straight to the heads (i hope not)?
with dbx, i realize that it's a two way process needing to be recorded onto tape then used to process during playback. so, would i need two sets of in/out jacks for compressing (in)/ monitoring (out), and recorded signal (in)/ expanding (out)?
i feel more interested in the hx pro method, than dbx, but would like to know about both. i know that there are pro audio independent dbx processors, but am interested in knowing if a broken cassette deck with dbx can be turned into an independent processor itself.
specifically, i want to use the hx pro with recording onto 8 track cartridges. i'd like to extend their headroom, lowering the noise floor. is this technically possible? does hx pro have some cassette- specific eq applied to it, that wouldn't work with the 1/4" tape in 8 tracks? seems like it should be able to work, somehow, because - 1) isn't a circuit, a circuit?! as long as you do it right, can't you send something through it, getting something different on the other end...good or bad? 2) even though 8 tracks use 1/4 inch tape, the track sizes are the same as cassette. the difference being that they are recorded at 3 3/4 inches per second vs. 1 7/8.
secondarily, i want to use this with vhs and reel to reel technology, but realize that it may not be necessary since they both have relatively lower noise floors.
help!