KVR Audio

mandt · Post by **mandt** » Fri Mar 21, 2008 9:19 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?

shamann · Post by **shamann** » Fri Mar 21, 2008 9:44 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 · Post by **Gartanius** » Fri Mar 21, 2008 9:52 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.

jupiter8 · Post by **jupiter8** » Fri Mar 21, 2008 9:55 pm

http://www.soundonsound.com/sos/jun07/a ... 0607_5.htm

mandt · Post by **mandt** » Fri Mar 21, 2008 10:28 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 . . .

shamann · Post by **shamann** » Fri Mar 21, 2008 11:17 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 . . .

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.

Music Engineer · Post by **Music Engineer** » Sat Mar 22, 2008 1:32 am

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.

mandt · Post by **mandt** » Sat Mar 22, 2008 7:26 am

Was this plug ever available? Sounds quite interesting and useful!

Music Engineer · Post by **Music Engineer** » Sat Mar 22, 2008 8:54 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

cymatics · Post by **cymatics** » Sat Mar 22, 2008 2:59 pm

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.

contrary · Post by **contrary** » Sun Mar 23, 2008 1:58 am

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 · Post by **cymatics** » Sun Mar 23, 2008 2:46 pm

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!!!

mauseoleum · Post by **mauseoleum** » Sun Mar 23, 2008 3:32 pm

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 · Post by **cymatics** » Sun Mar 23, 2008 4:20 pm

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

1.5% on a 2.4 GHz P4.

Download SOphist · Post by **Download SOphist** » Sun Mar 23, 2008 7:23 pm

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!

Leveling Amps; Fact or Fiction?