Leveling Amps; Fact or Fiction?

VST, AU, etc. plug-in Virtual Effects discussion
mandt
KVRian
600 posts since 29 Dec, 2006 from Sealand, North Sea

Post Fri Mar 21, 2008 1:19 pm

Sorry, no great gear test here, just an observational question . . .

Last night I looked through a Sweetwater catalog and concluded that the feverish volume of hyperbole regarding use of vintage-speak to sell products has reached its zenith. To wade through the BS to try and acquire actual solid information is quite daunting. No disrespect meant to Sweetwater but, come on, how can everything be 'analog' and 'tube' and have 'warmth' and be 'fat'? Which brings me to a question. I noticed that the latest advert buzz word for compressors is 'leveler' or 'leveling amplifier' and I got to wondering; is there a difference between a limiter and a leveling amplifier? To me, they're one in the same . . .

Or am I missing something?
I still think, your punctuation sucks, and your spelling isn't cool! So there...

shamann
KVRAF
12245 posts since 18 Aug, 2003

Post Fri Mar 21, 2008 1:44 pm

Levelling amplifiers are a kind of compressor, generally where the threshold and ratio are tied to the same parameter.

Limiters are a kind of compressor, just with a really high, fixed ratio, so not the same as a levelling amp.

Gartanius
KVRist
110 posts since 20 Jul, 2007 from Reading, PA - USA

Post Fri Mar 21, 2008 1:52 pm

shamann wrote:Levelling amplifiers are a kind of compressor, generally where the threshold and ratio are tied to the same parameter.

Limiters are a kind of compressor, just with a really high, fixed ratio, so not the same as a levelling amp.
Just as an add-on to this quote:

Levelers are alot nicer and simpler to use than a compressor if you are either unfamilliar with a compressor or if you aren't in the mood to spend the extra time adjusting compressor knobs for exactly what you want.

Limiters are more on the nifty side to get some minor distortion levels that are more like a tape recorder recording at some odd spot in the room. After you drop the volume down a bit, I suppose.

Well, that's how I use them anyway.

User avatar
jupiter8
KVRAF
9384 posts since 17 Sep, 2002 from Gothenburg Sweden

Post Fri Mar 21, 2008 1:55 pm


mandt
KVRian
600 posts since 29 Dec, 2006 from Sealand, North Sea

Post Fri Mar 21, 2008 2:28 pm

shamann wrote:Levelling amplifiers are a kind of compressor, generally where the threshold and ratio are tied to the same parameter.
. . . So any compressor can be a leveling amp by setting the threshold and comp ratio the same?

Edit: Yes they can. I just read the SOS article: "The term 'levelling amplifier' is just another name for a compressor. It was the popular name back in the '50s and '60s . . ." Hence why the term is being used more and more in adverts, so as to tie a product in to the golden age of audio perfection (or, imperfection) that everyone wants . . . :cry:
I still think, your punctuation sucks, and your spelling isn't cool! So there...

shamann
KVRAF
12245 posts since 18 Aug, 2003

Post Fri Mar 21, 2008 3:17 pm

mandt wrote:Edit: Yes they can. I just read the SOS article: "The term 'levelling amplifier' is just another name for a compressor. It was the popular name back in the '50s and '60s . . ." Hence why the term is being used more and more in adverts, so as to tie a product in to the golden age of audio perfection (or, imperfection) that everyone wants . . . :cry:
Kind of, yes. I'd guess a lot of it has to do with the esteem for the Teletronix LA-2A, an UA's clone/remake.

User avatar
Music Engineer
KVRAF
3830 posts since 8 Mar, 2004 from Berlin, Germany

Post Fri Mar 21, 2008 5:32 pm

i once wrote a small experimental plugin which attenuates when the signal-level is above some target level and boosts when it is below. kind of bi-directional compression which *I* called 'Leveller' at this time. dunno whether or not this is standard terminology. probably not. but it described best what the algo did - namely: bringing the signal level closer to some target level.
Image

mandt
KVRian
600 posts since 29 Dec, 2006 from Sealand, North Sea

Post Fri Mar 21, 2008 11:26 pm

Was this plug ever available? Sounds quite interesting and useful!
I still think, your punctuation sucks, and your spelling isn't cool! So there...

User avatar
Music Engineer
KVRAF
3830 posts since 8 Mar, 2004 from Berlin, Germany

Post Sat Mar 22, 2008 12:54 am

mandt wrote:Was this plug ever available? Sounds quite interesting and useful!
i never published it, did not even make a GUI for it...but hell, here it is:

www.braindoc.de/vst/Leveller.zip

my idea was to divide the signal by its envelope (plus some constant to avoid huge gain when the signal level is close to zero). something like:

outSignal = targetLevel * inSignal / (envelope + c)

where the constant c is determined by the maximum boost, i.e. when c = 0.1, the maximum boost would be a factor 10. that maximum boost is then expressed in dB and given to the user as parameter...along with the more obvious parameters. something like that from the top off my head.... it's really long ago and i did not really elaborate the idea. so no guarantees whether it even works as expected
Image

cymatics
KVRist
88 posts since 28 Dec, 2004

Post Sat Mar 22, 2008 6:59 am

mandt wrote:Sorry, no great gear test here, just an observational question . . .

Last night I looked through a Sweetwater catalog and concluded that the feverish volume of hyperbole regarding use of vintage-speak to sell products has reached its zenith. To wade through the BS to try and acquire actual solid information is quite daunting. No disrespect meant to Sweetwater but, come on, how can everything be 'analog' and 'tube' and have 'warmth' and be 'fat'?
By all means... disrespect Sweetwater. They are beyond shameless when it comes to misrepresenting products with marketing buzzwords, exaggerated claims, and outright lies.
There's nothing an agnostic can't do if he really doesn't know whether he believes in anything or not.

contrary
KVRian
1294 posts since 13 Mar, 2007

Post Sat Mar 22, 2008 5:58 pm

When compressors first became available , they were very , very simple devices that were meant to controll the overall dynamic range. They did'nt have a threshold or a knee. If you looked at the transfer curve , the usual 45 degree diagonal line that represents linear gain was simply tilted on a center "hinge point " . Everything in the upper levels got lowered and Everything in the bottom got raised. Leveling indeed!

cymatics
KVRist
88 posts since 28 Dec, 2004

Post Sun Mar 23, 2008 6:46 am

Robin from www.rs-met.com wrote:i never published it, did not even make a GUI for it...but hell, here it is

.... it's really long ago and i did not really elaborate the idea. so no guarantees whether it even works as expected
Holy crap Robin!!! You've been sitting on a real gem there.

That is one excellent dynamics processor. Seriously close to the sound of a good hardware device.

With apologies to Aleksey (I used a drum clip he posted in another thread) here is a quick demo of Leveller doing a fantastic job mimicking a Beatles-esque drum squash (think the end of 'Come Together'). The first half is the dry clip; the second half is processed with Leveller.

Leveller Test

I have a mix session with a client this evening. I'll be trying this on a variety of sources.

Thanks Robin!!!
There's nothing an agnostic can't do if he really doesn't know whether he believes in anything or not.

mauseoleum
KVRAF
1907 posts since 29 Oct, 2003

Post Sun Mar 23, 2008 7:32 am

Hey! This plugin sounds very catchy! It's got the mojo, especially on syncopated material.

@dev:
Why don't you tweek it a bit further? I doesn't have to have the GUI. In fact, I like it better without the GUI. Similar to LOSER plugins.

cymatics
KVRist
88 posts since 28 Dec, 2004

Post Sun Mar 23, 2008 8:20 am

Oh yeah... easy on the CPU as well. :)

1.5% on a 2.4 GHz P4.
There's nothing an agnostic can't do if he really doesn't know whether he believes in anything or not.

Download SOphist
KVRAF
3909 posts since 26 Jan, 2006 from :noitacoL

Post Sun Mar 23, 2008 11:23 am

Robin from www.rs-met.com wrote:i never published it, did not even make a GUI for it...but hell, here it is:

www.braindoc.de/vst/Leveller.zip
the idea sounds gorgeous. thanks for the link Robin!
professional dilettante, producer, sound-designer, re-mixer, self-righteous, fail.

Return to “Effects”