compressors per channel

[ruairioflaherty]

Makes sense Doug but I'd add that nobody is mixing broadcast on an analog board anymore!  If this is really more than a thought exercise for Pucho then we have to look at how people are really working these days. 

DAWs have presets covered, what I want is a a hands on compressor that I can dial in quicker than I can find the closest preset.  FWIW I hated using that Titan but I'm not a Swiss Army Knife kinda guy.

DAWs have recall covered, if I need fast recall (and almost all pro mixers I work with do) then I stay in the box and use minimal if any outboard.

It's a personal opinion but I think plug in compressors can control dynamics and hold things in place reasonably well, where analog shines is in shaping the sound.  I use both in my mastering daily but I almost always use digital compressors to make things smaller and more contained, never to shape transients or enhance groove.

Optos are a non runner these days anyway, parts are hard to find. 

A FET compressor that you could linearize enough to be a generally useful tool could work, and it would have the advantage that you could un-linearize it with a "fun" button.

 

[abbey road d enfer]

I like these thoughts but would add, as I understand it, attack and release in a dbx type circuit is peak detection with modified timing, differing greatly in sound and distortion profile from dbx 'overeasy' rms detection.  If I can only have one, I want it to be rms overeasy.  Especially if it's 8 talking heads in broadcast with more downstream processing.

Overeasy and adaptive timing are not mutually exclusive; you can have one, teh other or both. I mentioned the possibility of adding a soft/hard switch earlier, soft being overeasy.

 

[emrr]

Overeasy and adaptive timing are not mutually exclusive; you can have one, teh other or both. I mentioned the possibility of adding a soft/hard switch earlier, soft being overeasy.

Right

 

[ruairioflaherty]

Makes sense Doug but I'd add that nobody is mixing broadcast on an analog board anymore!  If this is really more than a thought exercise for Pucho then we have to look at how people are really working these days. 

DAWs have presets covered, what I want is a hands on compressor that I can dial in quicker than I can find the closest preset in a DAW or digital console.  FWIW I hated using that Cranesong Titan but I'm not a Swiss Army Knife kinda guy.

DAWs have recall covered, if I need fast recall (and almost all pro mixers I work with do) then I stay in the box and use minimal if any outboard.

It's a personal opinion but I think plug in compressors can control dynamics and hold things in place reasonably well, where analog shines is in shaping the sound.  I use both in my mastering daily but I almost always use digital compressors to make things smaller and more contained, never to shape transients or enhance groove.

Optos are a non runner these days anyway, parts are hard to find. and ROHS etc.

A FET compressor that you could linearize enough to be a generally useful tool could work, and it would have the advantage that you could un-linearize it with a "fun" button.

 

[emrr]

Makes sense Doug but I'd add that nobody is mixing broadcast on an analog board anymore!

So you would think, but I keep mixing press conferences for live broadcast on them as that's what's supplied by the contractor to the contractor to the contractor for sports events. 

 

[ruairioflaherty]

So you would think, but I keep mixing press conferences for live broadcast on them as that's what's supplied by the contractor to the contractor to the contractor for sports events.

Cool, glad to hear that. Let me be more specific, no one is buying analog consoles for broadcast. There's definitely gear in the field in use.  Again, I'm wondering if Pucho is thinking about a real design or if it's just a mental exercise. 

I'd always prefer to mix live on an analog board.

 

[emrr]

Cool, glad to hear that. Let me be more specific, no one is buying analog consoles for broadcast. There's definitely gear in the field in use.  Again, I'm wondering if Pucho is thinking about a real design or if it's just a mental exercise. 

I'd always prefer to mix live on an analog board.

I've mostly ran digital mixers in the field for live and broadcast events in the last 4 years.  I can say the analog mixer in question for broadcast use was specified because the A1 is always a local, and the contractor must have a system that any pickup tech can drive, with no learning curve.  It would require a different operational protocol for them to go with a digital mixer in the future....like bringing a dedicated crew....I'd say there are definitely live event people who would not be able to go into that particular job on an unknown digital mixer without a crash and burn. 

 

[pucho812]

Well  let's see beyond thought process.  Shall we. Every topology will have pros and cons. This we know. 

What about a pwm compressor per channel and kill any vibe we have

 

[abbey road d enfer]

Well  let's see beyond thought process.  Shall we. Every topology will have pros and cons. This we know. 

What about a pwm compressor per channel and kill any vibe we have

I wouldn't venture myself i this territory. PWM gain control involves questionable filters. And unless all operate on a common distributed clock, possible interference is an additional issue.

 

[ruairioflaherty]

I wouldn't venture myself i this territory. PWM gain control involves questionable filters. And unless all operate on a common distributed clock, possible interference is an additional issue.

Agreed and PWM is not sexy in the consumers eyes.  Ask the average engineer (not us geeks) to name a PWM compressor and you'll be met with a blank stare, maybe 1 in 10 could suggest Pye….maybe.  Compare that to "Varimu" as a selling point.

I'd need a lot more info on the target audience to make any kind of useful suggestions. 

 

[zamproject]

Agreed and PWM is not sexy in the consumers eyes.  Ask the average engineer (not us geeks) to name a PWM compressor and you'll be met with a blank stare, maybe 1 in 10 could suggest Pye….maybe.  Compare that to "Varimu" as a selling point.

I'd need a lot more info on the target audience to make any kind of useful suggestions.

mmm...more or less the same with varimu for "average" engineer ?
maybe easier to name one, but only 1 in 10 don't name Manley 
PWM daily user here, not one, but 10 loaded in the desk, which is not far from one per channel (when comp inserted)
But yes, it's not the easier design to fit at each channel. and high frequency switch section need special care.

Best
Zam

 

[abbey road d enfer]

PWM daily user here, not one, but 10 loaded in the desk,

Which compressor? Can you describe what made you choose it?

 

[zamproject]

Which compressor? Can you describe what made you choose it?

hey abbey

Studer x89 modular series console,  the desk nor the compressor modules is clean compared to modern digital standard, but the compression itself is pretty "transparent", pumping effect is low even at extreme setting
Also as a 3 button setting (ratio/release/gain) it's an instant and easy tuning.
For sure not always the greater choices, but always a good result to handle dynamic so it's my basic go to
When more envelop/fx way is requested, I patch VCA comp
Finally I choose them because  I have them and a lot... (not saying I have them so I have to use them anytime anywhere!)

By the way sw freq is about 300kHz, low pass -3dB at 30kHz and the high freq osc section is in a mu-metal box  :

Best
Zam

 

[abbey road d enfer]

By the way sw freq is about 300kHz, low pass -3dB at 30kHz and the high freq osc section is in a mu-metal box  :

Yes, I checked that; the oscillator is free-running, no sync from a master clock. I would be worried about frequency-beating...
Low Pass filter is 7th-order-ish, clock rejection should be about -140dB.

Timing/pumping/transient response is confined to the side-chain; that's the beauty of a linear VCA. Other types have the gain cell element interfering with the side-chain, particularly optos, that's a reason why some love them, but broadcast designers don't like this element of surprize.

 

[zamproject]

Yes, I checked that; the oscillator is free-running, no sync from a master clock. I would be worried about frequency-beating...
Low Pass filter is 7th-order-ish, clock rejection should be about -140dB.

what do you mean ? non stable clock ? or some king of interference/submodulation ?

yes rejection is good i never heard the clock

Best
Zam

 

[abbey road d enfer]

what do you mean ? non stable clock ? or some king of interference/submodulation ?

yes rejection is good i never heard the clock

Best
Zam

You can't hear the clock at 300 kHz, but you could hear the beating tone between two slightly different clocks. Let's say one is at 301kHz and the other at 299, you could hear a 2kHz beating if you mixed both signals.

 

[zamproject]

You can't hear the clock at 300 kHz, but you could hear the beating tone between two slightly different clocks. Let's say one is at 301kHz and the other at 299, you could hear a 2kHz beating if you mixed both signals.

Ok, get your point, that's what I'll call intermodulation then.
I can't see a situation where it can occur, clock is shared by parr (stereo modules whatever sc link engaged or not) so no issue with stereo material.
Maybe if I process the exact same signal via two different comp ? but it's not a use case
And the clock have to pass the filter I guess !

Next time I check and align the modules I'll set a Lissajous at the scope to tune all clock modules equal  :

Best
Zam

 

[abbey road d enfer]

Ok, get your point, that's what I'll call intermodulation then. 

Not really; intermod involves non-linearities in the transfer function. Beating happens in linear systems. Check
https://en.wikipedia.org/wiki/Beat_(acoustics)

I can't see a situation where it can occur, clock is shared by parr

I don't see that on the schemo; the 7555's are free-running.

(stereo modules whatever sc link engaged or not) so no issue with stereo material.

As the name implies, it's only the side-chains that is linked, I don't see any connection going out or into the 7555.

Maybe if I process the exact same signal via two different comp ?

No, just having two channels routed to the same output.

And the clock have to pass the filter I guess !

Wet-finger calculation says clock atenuation may be about 100dB real world, which is probably enough.

Don't sweat it; Studer's designers have done it long ago. My comment was addressed to anyone who would want to design a PWM gain cell and put it in a mixer.

 

[zamproject]

Ho !
I don't think we talk about the same compressor 
There is no 7555 in my 1977 Studer 289  !
I suppose you refer to the late 80' 96x series which have "PDM-VCA" compressor fitted at master modules
which is a PWM of course...

Best
Zam

ps:tks for the wiki link

 

[abbey road d enfer]

I don't think we talk about the same compressor 
There is no 7555 in my 1977 Studer 289  !
I suppose you refer to the late 80' 96x series which have "PDM-VCA" compressor fitted at master modules
which is a PWM of course...

Exactly.
I'll look if I can find the 289.

EDIT; OK I've found the schemo; indeed there's a single oscillator for two channels, so there's no risk of beating. The low-pass filter is only 5th order so the clock must be about -80dB below nominal signal.