I'm archiving some old 4 track cassette masters into pro tools. The
original recorder had dbx Type 1 NR switched on, but I don't have that
machine any more. I'm using a simpler 4 track cassette to play the tapes
into my DAW; this machine is not equipped with dbx.

Is there any way to use a plugin to compensate for the effects of the dbx?

If not, no biggie. These are songs I wrote 20 years ago and frankly
posterity won't care a whole lot if the recordings sound sucky. Just for my
own nostalgia.

malachi

"Malachi" wrote in message
. net...
I'm archiving some old 4 track cassette masters into pro tools. The
original recorder had dbx Type 1 NR switched on, but I don't have that
machine any more. I'm using a simpler 4 track cassette to play the tapes
into my DAW; this machine is not equipped with dbx.

Is there any way to use a plugin to compensate for the effects of the dbx?

If not, no biggie. These are songs I wrote 20 years ago and frankly
posterity won't care a whole lot if the recordings sound sucky. Just for
my own nostalgia.

malachi

IIRC, dbx NR was/is 2:1 compression with a threshold of... well, anything -
meaning the entire program was compressed @ 2:1. So an expander at 2:1 with
lowest possible threshold should get you in the ballpark if you can't find a
decoder.

Mikey
Nova Music Productions

Thanks, I'll give it a try.

malachi

"Malachi" wrote in message
. net...
I'm archiving some old 4 track cassette masters into pro tools. The
original recorder had dbx Type 1 NR switched on, but I don't have that
machine any more. I'm using a simpler 4 track cassette to play the tapes
into my DAW; this machine is not equipped with dbx.

Is there any way to use a plugin to compensate for the effects of the dbx?

If not, no biggie. These are songs I wrote 20 years ago and frankly
posterity won't care a whole lot if the recordings sound sucky. Just for
my own nostalgia.

malachi

In article et,
"Michael Wozniak" wrote:

"Malachi" wrote in message
. net...
I'm archiving some old 4 track cassette masters into pro tools. The
original recorder had dbx Type 1 NR switched on, but I don't have that
machine any more. I'm using a simpler 4 track cassette to play the tapes
into my DAW; this machine is not equipped with dbx.

Is there any way to use a plugin to compensate for the effects of the dbx?

If not, no biggie. These are songs I wrote 20 years ago and frankly
posterity won't care a whole lot if the recordings sound sucky. Just for
my own nostalgia.

malachi

IIRC, dbx NR was/is 2:1 compression with a threshold of... well, anything -
meaning the entire program was compressed @ 2:1. So an expander at 2:1 with
lowest possible threshold should get you in the ballpark if you can't find a
decoder.

Mikey
Nova Music Productions



It also employed pre-emphasis/de-emphasis equalization so you'll need to do that
after expanding. There's a decent description of the encoding process in John
Woram's Sound Recording Handbook. Decoding doesn't appear to be a trivial
pursuit.

-Jay
--
x------- Jay Kadis ------- x---- Jay's Attic Studio ------x
x Lecturer, Audio Engineer x Dexter Records x
x CCRMA, Stanford University x http://www.offbeats.com/ x
x---------- http://ccrma.stanford.edu/~jay/ ------------x

I'm archiving some old 4 track cassette masters into pro tools. The
original recorder had dbx Type 1 NR switched on, but I don't have that
machine any more. I'm using a simpler 4 track cassette to play the tapes
into my DAW; this machine is not equipped with dbx.

Is there any way to use a plugin to compensate for the effects of the dbx?

If not, no biggie. These are songs I wrote 20 years ago and frankly
posterity won't care a whole lot if the recordings sound sucky. Just for
my own nostalgia.

I've done this before with Dolby B NR, and what worked well for me was to
use Waves C1 comp-gate, which offers a sidechain-able expander. Bypass the
compressor and use a high-pass sidechain filter set to somewhere between
4-6kHz, about 6dB of expansion, with very short attack (try 0.8ms) and short
release (try 5ms to start). Play around with that, then you should apply
DINR or a similar noise reduction plug-in. DINR is good to about 7dB of
attenuation, but for very noisy content it can be applied twice for 14dB
reduction total, with acceptable artifacts that are only discernable with
headphones.

On Apr 13, 2006, Malachi commented:

I'm archiving some old 4 track cassette masters into pro tools. The
original recorder had dbx Type 1 NR switched on, but I don't have that
machine any more.
------------------------------snip------------------------------

If you want to borrow two channels of dbx Type 1 NR, talk to me in email. If
you'd guarantee their prompt return and pay shipping both ways, I'd consider
doing it gratis.

--MFW