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Dolby "warble" tone? What is this?

Delivery specs for a project ask for Dolby "warble" tone. This is on a Digibeta. I'm at a total loss. Dolby has no info on "warble tone".
What is it, and what is it used for, and how can I generate it?

Thanks.

Comments

Member for
51 years 5 months

RobinH Sat, 03/23/2002 - 14:15

Sounds like the carrier wave dolby would use to encode the information. I have no idea how you would get this though. Maybee ask technical support for your equipment.

Profile picture for user anonymous
Member for
20 years 9 months

anonymous Sat, 03/23/2002 - 17:58

I have heard it and I be damned if I can remember what the hell its for eactly

(calibration obviously but what in particular)

I bet someone here remembers!

It warbles like a muted, underwater, 1k test tone..

Member for
19 years 10 months

Richard Kuschel Sun, 03/24/2002 - 07:13

The Dolby "Warble Tone" is for calibration of the Dolby Professional noise reduction system (Type A, perhaps others ) . It is to be placed on the tape reel so that the system may be recalibrated for proper playback.

It sounds weird so that it may be distinguished from other calibration tones. While it sounds as though it varies in level, it does not. Without that tone any adjustment for playback on a Dolby system is hit or miss. :(

Member for
19 years 10 months

Richard Kuschel Sun, 03/24/2002 - 07:16

In addition, the tone is generated from within the Dolby encoder.

The tone is generated and read with the Dolby Process OFF.

If yOu need further information,contact me and I will lookit up in my service manuals. :w:

Profile picture for user RecorderMan
Member for
20 years 2 months

RecorderMan Mon, 03/25/2002 - 07:16

[QUOTE]Originally posted by Richard Kuschel:
[QB]The Dolby "Warble Tone" is for calibration of the Dolby Professional noise reduction system (Type A, perhaps others ) . It is to be placed on the tape reel so that the system may be recalibrated for proper playback.

BINGO. this is exactly what it is (boy do I feel old). Dolby A.

Hey Boom Chic. If you need info on set up and calibration I cab give you the details. or email me...I'm in LA as well.

BONUS TIP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Did you know?
The Dolby A card (usually the CAT22 card in a 361 module) can be used (preferably after a modification to the circuit board) as the PHATEST aurell exciter ever?

You've heard this on quite a few records in the past. It's that real airy, " I can hear the tonsiles" sound. Send and Aux to the dolby unit (set in 'encode' mode); return the "to record" out put of the dolby on another fader and blend back in (usually around -10db).
The Top end expansion, that is produced by this will make a '57 sound like a c12 (not really but....). Very, very cool on vocals and a-gtrs. The Original Dolby Stretch 301(HUGE grey four card behemoths) units from the '60 were the first ones that were used for this. As usual, in their quest to create great sounds and without the fear of "breaking it" it was "discovered" originally by G. Martin on the Beatles (or so I was told by the producer that got this secrect from GM, and subsequently figured out the mod for the cheaper and more common Dolby A Cat.22 card).
As this process is level dependent (it adds "air" to signals below 0db

it doesn't make the singer sound edgy when they get loud. To really do this right though, you need the mod. It by passes the Lo and Lo-Mid compression and eliminetes the pumping a that a "proper" Cat.22 card will give you. I can't describe the mod...but I have a few, and can do (and have done ) the mod by copying it from thje ones I have (Got them from earlier said Producer.)
I've seen allusions to this mentioned before (I think Eddie Callienti {spellig?] ) mentioned it a year or two ago in EQ. BUT he didn't mention the mod. He probably didn'y know about it....few do.
So...if anybody out there is interrested... we can talk about this.
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