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Old 03-11-2019, 08:46 AM
Peter Baird's Avatar
Peter Baird Peter Baird is offline
Join Date: Jan 2005
Location: Stevenson Ranch, CA
Posts: 253
Default Fun fact.

I wanted to play around with a pair of oscillators, so I started a new session, made 2 new tracks, and inserted the Tone Generator on each. I hear enough 1K in the course of my life, so I pulled the frequency in each genny down to 200Hz. With both channels panned hard left and one channel open, my left output VU meter (as expected) settled at 0dB. But when both channels were open, the output dropped to below -8dB. Just for grins I inserted the 1-band EQ on one of the channels and flipped the phase. Sure enough the output jumped to pin the meter.

Thinking this to be somewhat odd, I looked at both gennys to see if I had done something stupid. Nope, everything was exactly the same. So I started changing the waveform on one of them randomly, and behold, every time I changed the waveform a different phase result happened. It took me a while to realize that each time I changed the waveform the oscillator instantly restarted, and that restart could happen at any point of the sinusoidal wave coming from the other genny.

So of course the next question was, if I instantiate both gennys simultaneously will they be in phase? And yes, they were.

Which is a long ways to say that if you start two oscillators going at different times, even if they are the same frequency, you will get random phase results. Duh.

As you were.

(Alas, I was mistaken. Changing the waveform does not actually seem to re-start the genny. The differences when swapping waveforms seem to be due to the different harmonic makeup of each waveform. The only way to re-start the genny seems to be re-instantiating the plug.)

Gypsy: PT Ultimate 2019.5, 12-core Mac Pro 3.46Ghz 64GB OS 10.14.5, HD Native, HD OMNI, 2 Artist Mix, EUCON 18.3, Presonus 32R, Studio One 4.5.1, Quad Eight preamps, Neve 3201 EQs, 2 LA-4s, Malone Design Works desk

Laptop: 10.13.6 MacBook Pro 2.8 Core i7, 16G, PT 19.5 Live 9


Last edited by Peter Baird; 03-11-2019 at 09:02 AM. Reason: Mistake!
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Old 03-11-2019, 09:06 AM
the.engineer the.engineer is offline
Join Date: Nov 2009
Location: Guildford, Surrey, UK
Posts: 221
Default Re: Fun fact.

I used to run genny's across all tracks to do calibration and stuff until I also realised that they were outputting their sine's at different times.

Amazing what you find once you start digging.
James Welch
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Old 03-11-2019, 12:25 PM
john1192 john1192 is offline
Join Date: Nov 2001
Location: Woodland Hills
Posts: 5,694
Default Re: Fun fact.

use one Genny, and Bus it to all the other tracks you want to Calibrate !! maybe .. if just aligning desk / PT to record machines

too bad there is not a MASTER genny, but that Would change the flexibility of having different tones on different tracks for easy ident in the heat of the moment ..
OS 10.12.6 for PT 11.3.2 & 12.4 & above
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Old 03-13-2019, 04:16 AM
clancychris clancychris is offline
Join Date: Nov 2010
Location: Lancashire, UK
Posts: 77
Default Re: Fun fact.

For calibration I always print signal generators for this reason. I thought I was going mad trying to balance everything up on a mixer until I realised they weren't synchronised.
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Old 03-13-2019, 10:55 AM
Sonopolis Sonopolis is offline
Join Date: Sep 2011
Location: Berlin
Posts: 230
Default Re: Fun fact.

I have an even funnier application for the signal generator: try to make a sweep by automating the frequency. Interesting results await you!
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