The No.1 Website for Pro Audio
 Search This Thread  Search This Forum  Search Reviews  Search Gear Database  Search Gear for sale  Search Gearslutz Go Advanced
limiter / clipper EXACT difference ??
Old 1st July 2009
  #1
Lives for gear
 
miro's Avatar
 

limiter / clipper EXACT difference ??

aloha

can someone explain the exact difference between a limiter and a clipper?
i believe to know what a limiter does but what's exactl¥ the clipper doing?


Old 1st July 2009
  #2
Lives for gear
 
Greg Reierson's Avatar
 

Verified Member
A clipper is a limiter with zero attack and release time constants.
Old 1st July 2009
  #3
Lives for gear
 
Cellotron's Avatar
 

Verified Member
Quote:
Originally Posted by Greg Reierson View Post
A clipper is a limiter with zero attack and release time constants.
What Greg said - although there are indeed "soft clippers" that have a knee (sometimes even adjustable) for these parameters - although it could be argued that these are more "limiters" than "clippers". Anyway - a clipper basically lops off any transient that reaches the set threshold so that the wave form is "flat topped" at its highest points. Where as some digital limiter algorithms can "rescale" the audio so that the wave form doesn't get flat topped (at least as dramatically) even as average level is increased.

Best regards,
Steve Berson
Old 2nd July 2009
  #4
Lives for gear
 
Table Of Tone's Avatar
 

Verified Member
In theory, it should be better to scale the waveform but it won't always sound better.
With limiters, you can almost transparently loose the nice transients!
You sometimes wouldn't even know they were ever there, if you hadn't heard the original mix.
I would normally turn to some kind of clipper if I wanted to avoid some of the digital stardust that a belted converter can make.
The clipper can sometimes allow you to not hit the ADC so hard and make up a little gain after it.
Old 3rd July 2009
  #5
Lives for gear
 
miro's Avatar
 

thanks alot!
Old 3rd July 2009
  #6
Lives for gear
 
Ben F's Avatar
 

Verified Member
Essentially a clipper will distort the signal more, but can actually sound snappier than limiting if used properly. Clipping was commonly used for FM and AM broadcasting before the transmitter to bring up the levels (along with compression).

Clipped waveforms are exceedingly high in THD, and will cause aliasing with most audio codecs. So a clipped waveform (or clipping the AD converter) may sound better in the studio, but will sound worse as and MP3 or on digital radio than using a limiter. Look ahead limiters are preferred when using codecs as they have a lower THD than clipping, and will not alias the system.

Having said all of that, you will find clipping the AD is very common. Most MEs are guilty (including me).
Old 4th July 2009
  #7
Lives for gear
 
Jesse Graffam's Avatar
 

Quote:
Originally Posted by Ben F View Post
Clipping was commonly used for FM and AM broadcasting before the transmitter to bring up the levels (along with compression).
It still is.


Quote:
Originally Posted by Ben F View Post
Clipped waveforms are exceedingly high in THD
It depends on the method used to clip. There's a number of distortion-masking clippers, a few are better than many.


Quote:
Originally Posted by Ben F View Post
and will cause aliasing with most audio codecs.
Actually, the aliasing is already there before coding.


Quote:
Originally Posted by Ben F View Post
So a clipped waveform (or clipping the AD converter) may sound better in the studio, but will sound worse as and MP3 or on digital radio than using a limiter. Look ahead limiters are preferred when using codecs as they have a lower THD than clipping, and will not alias the system.
If you don't hear the aliasing in the studio, try getting high quality headphone playback in it. If you're hearing aliasing on the radio, or on mp3 (likely you are then listening to the mp3s on headphones, right?), then it's already in your tracks.
Old 5th July 2009
  #8
Lives for gear
 
Table Of Tone's Avatar
 

Verified Member
I find there is a balance between how hard you hit the ADC and how much gain you make up using some kind of clipper.
If you get that balance right and make an MP3 from a 24 bit file, you can get it to sound pretty good for an MP3.

I'm biased because I personally don't like limiters and don't use em!
I like the punch left just the way the mix engineer intended.

The recording engineer spends a ton of time getting a killer drum sound on a track only to have the nuts taken out of it at the mastering stage, because of the use of a lookahead limiter at the end of his chain.

Not in my studio!
Old 3rd May 2019
  #9
Lives for gear
 
DistortingJack's Avatar
 

ELI5: A clipper shaves the top of the waveform. This creates harmonic distortion, a bit like with a guitar pedal. However if you just use it to shave off very short transients, it basically creates tiny bursts of treble distortion where before you just had a volume peak, and sometimes that burst sounds like more volume and definition. It can work great to have some clipping on percussive transients. The only real parameter you have is how softly it shaves off the top; if it's softer, then it starts distorting at lower levels. If it's just sawing off the top, it will be 100% clean until you reach 0, but the distortion might sound worse.



A limiter (at least a modern digital limiter with lookahead algorithms) ideally pulls the signal down proportionally from the zero crossing, in a way defined by the attack and release parameters. This means that the peak isn't shaved (no distortion frequencies added) but just made quieter. The resulting sound is usually more transparent, but does not replace the volume burst with extra frequencies so it sounds less punchy. However, you can, by having very aggressive parameters, have some distortion on a pure limiter, which sounds very different depending on the model and the algorithm they use.

The best combination of volume, punch, and transparency comes from a judicious combination of the two. Depending on the style of music, even small amounts of clipping might sound awful.
Old 3rd May 2019
  #10
Motown legend
 
Bob Olhsson's Avatar
 

Verified Member
Something else to consider is that a clipped master can be very fragile and sound pretty bad when it gets clipped again by a broadcast processor.
Old 3rd May 2019
  #11
Clipping is often the best choice for noise-like content such as drums/percussion and, by a certain amount, vocals and guitars. Signal wise, anything that's short will likely be very noisy, or almost (heard this applies to humans too, lol, no idea if that's true ).

Most instrument's leading transients are noise like.

As mentioned above already, clippers act instantly, they have no memory. This means they'll create lots of distortion on real world signals, mostly unharmonic with a slight amount of harmonic distortion. But this distortion is instant, so no event will ever affect any other. Sadly, this largely inharmonic distortion becomes extremely annoying once hit by steady tones, distorting the important harmonic relations.



A limiter on the other hand is optimal for constant, tonal content. Steady tones, long sustaining stuff such as bass, pads and so on. Limiters can handle these signals optimally.

Limiters achieve this by introducing memory into the process, to spread the distortion over time (and partly shift it elsewhere). It introduces whole new classes of problems as soon that signal isn't steady anymore. These problems show their effects over the mid and long term, across the spectrum and the stereo field. With the introduction of this memory, a single hi-hat can suddenly duck the next events (so called overcompression effects, when completely innocent signals get punished for what that previous hi-hat did ).


All modern maximizer type limiters use a combination of clipping and memory based limiters. Crudely: Clipping peaks, limiting the body.

Last edited by FabienTDR; 3rd May 2019 at 10:38 PM..
Old 3rd May 2019
  #12
Lives for gear
 
SmoothTone's Avatar
 

Quote:
Originally Posted by FabienTDR View Post
anything that's short will likely be very noisy, or almost (heard this applies to humans too, lol, no idea if that's true ).
It is!
Old 4th May 2019
  #13
Lives for gear
 
teebaum's Avatar
Quote:
Originally Posted by Greg Reierson View Post
A clipper is a limiter with zero attack and release time constants.
... and infinite ratio.
a softclipper with a ratio smaller than infinity, but approaching infinity
Old 4th May 2019
  #14
Lives for gear
 
macc's Avatar
 

Verified Member
So nearly a ten-year thread necro. If you'd only just waited a couple of months.
Old 4th May 2019
  #15
Lives for gear
 

Well, it's an educational necro and surely useful for somebody.

Anyhow, I'd like to add to @ FabienTDR and his always excellent post:

Even though clippers do not have memory, the annoying burst like distortion that happens can get really annoying in just a few minutes due to the human brain having memory. Thus even noise like sources like claps or noisy attack on kick, that would otherwise not bother in a single instance, can get annoying as they repeat in a predictable manner throughout the song. Thus the brain hears the clipping as a memory effect. The brain can also sort of "imprint" itself on the sound of the clipped stuff, that is the "noise burst" of the clipping.. and thus suddenly start noticing it all over the place. It can quickly become a question of "Once you hear it, you can't unhear it" and bring the listener out of the magic of the music.

Naturally this would only be the case with rather severe clipping though.

Just my 2 cents on the subject.
Old 4th May 2019
  #16
Lives for gear
 

Verified Member
techniques including two stages of comp/lim can help to keep things under control and can hide issues to some extent. another approach is to 'limit' issues to specific frequency bands by using dynamic eq's or multiband-limiters.

but i guess there will always be folks who clip things on purpose!
Old 4th May 2019
  #17
Motown legend
 
Bob Olhsson's Avatar
 

Verified Member
Something broadcasters discovered is that excessive clipping causes people to change stations after thirty seconds or so without knowing why they felt the need to.
Old 5th May 2019
  #18
Quote:
Originally Posted by Bob Olhsson View Post
Something broadcasters discovered is that excessive clipping causes people to change stations after thirty seconds or so without knowing why they felt the need to.
Most of the American Idol winners caused the same effect on me.

Feed a 1k sine wave into your favorite squasher and examine the waveform. Some will cleanly reduce the amplitude so the sine still looks sine. Some will flatten the top off to various degrees of 'roundness' on the sides. Less roundness/sharper corners = more odd harmonics. More roundness = less harmonics. Some have more odd than even partials.

The amount of harmonics will vary with levels too. It's a dirt chasing crap shoot.
Post Reply

Welcome to the Gearslutz Pro Audio Community!

Registration benefits include:
  • The ability to reply to and create new discussions
  • Access to members-only giveaways & competitions
  • Interact with VIP industry experts in our guest Q&As
  • Access to members-only sub forum discussions
  • Access to members-only Chat Room
  • Get INSTANT ACCESS to the world's best private pro audio Classifieds for only USD $20/year
  • Promote your eBay auctions and Reverb.com listings for free
  • Remove this message!
You need an account to post a reply. Create a username and password below and an account will be created and your post entered.


 
 
Slide to join now Processing…
Thread Tools
Search this Thread
Search this Thread:

Advanced Search
Similar Threads
Thread
Thread Starter / Forum
Replies
ubik / Electronic Music Instruments and Electronic Music Production
11
lydfar / So Much Gear, So Little Time
33
shadyru / Low End Theory
1
RobMacki / The Moan Zone
3
Aloha / So Much Gear, So Little Time
12

Forum Jump
Forum Jump