Hi Richard:
First of all, I would think dbx decoding would be easier with software because as I understand it's
a straight compansion ratio against all frequency bands, so there's no complexity of
frequency-specific processing.
That said, could you post examples like you did for Dolby.
I listened to the Dolby examples again and I really don't like the Satin processing. It screws up
the frequency balance and also the stereophony, plus the pumping issue. As I said, if I were doing
it, I'd use well-working Dolby hardware and do the decoding in the analog realm, and then do
professional mastering (ie tasteful EQ tweaks to make it sound less deadened).
For what it's worth, I have a 363 unit that I bought on eBay and it seems to work well, based on the
relative levels of the Dolby warble tone and 100, 1k and 10k test tones on a professionally made
Dolby A tape from the mid 1970s. I have not messed with SR because I don't have any SR tapes.
What would be very useful from the folks at Satin who have at least partially cracked the Dolby code
would be a Dolby C emulator that had a sensitivity control built in. A big problem with Dolby C
cassettes is that they lose signal level and then the Dolby C doesn't decode properly. This also
seems to be a problem with some videotapes, I'm not sure of all the formats but I think Betacam was
one of them. I'm glad I did not use Dolby C for very many hard to replace cassette recordings,
because it's problematic to get it work properly on machines not the original recorder and also with
25-year-old tapes that have lost signal level (see Jay McKnight's and others' comments on the Ampex
List and elsewhere about cassettes partially self-erasing over time; some deny this to be possible
but I have definitely seen these behaviors with my own Dolby C tapes made in the early 1990s).
Anyway, I think software that allowed for sensitivity or threshold control for the Dolby C, for each
of the bands (because the problem seems to be confined to that high-frequency band), might allow for
better tracking of old cassettes. And let me say one more time, I do not miss the Compact Cassette
one bit.
-- Tom Fine
----- Original Message -----
From: "Richard L. Hess" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Friday, August 14, 2015 9:52 PM
Subject: [ARSCLIST] Satin dbx I decode
> Hi, all, just a heads up. The Satin decode for dbx I is very close to my dbx I processor, but not
> exact. It is clearer and more open...again.
>
> So, as luck would have it, the power supply in my M-frame (I think) stopped working. That MAY have
> been the cause of the problems (low voltage perhaps someplace). I don't know.
>
> But I have a backlog of tapes to try and one of my two dbx frames has something wrong on the power
> bus (I don't know if a card is pulling it down or the supply is problematic) and now my Dolby M
> frame is out.
>
> Satin came along at just the right time.
>
> I'll try 16 tracks of Satin dbx I tomorrow on a 1" 16T tape that caused me to notice the 9-16
> frame was acting flaky. Now I can at least easily provide raw and processed versions of the
> transfer without needing 32 A-D channels or running an outboard realtime pass.
>
> What is WONDERFUL about Satin is that you don't have intermittent switches and lots of pots to
> adjust in difficult-to-reach places.
>
> I am seeing very few NR tapes.
>
> I think I'm going to pass on buying a 363 right now.
>
> 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.
>
>
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