Mastering, compression = crappy sounding crash cymbols

[FALKEN]

Okay....mulling this one over....thinking....thinking....alright, I give. What do you mean by this?

ok. when a signal is clipped the peak is just lopped off right?

the way a limiter works is when the signal exceeds the threshold, a gain reduction is applied. meaning the whole signal is attentuated, not just the peaks.

like when you're listening to the radio...sometimes when the singer's voice comes in the rest of the music gets quieter...same idea. on a limiter, which normally has an extremely fast release time, it can get really bad. which leads to my comment about seasickness. it might also explain why the OP's cymbals are sounding so bad. lengthening the release time to smooth things out might do the trick.

But what was the reason for not using the ebay machine for the mechanical workings and putting heads and the audio section from your broke machine into it; instead of trying to guess which parts need to be replaced with parts from the ebay machine. I'm afraid I have no idea what you should try, apart from killing yourself. That always seems to work.

I am about at that point.

I might swap the heads into the ebay machine; its still an option. whatever works.

 

[SouthSIDE Glen]

the way a limiter works is when the signal exceeds the threshold, a gain reduction is applied. meaning the whole signal is attentuated, not just the peaks.

Hello???? Hello???? Are you awake, Falken, or are you sleeptyping as a side effect of the Ambien again?

G.

 

[FALKEN]

Hello???? Hello???? Are you awake, Falken, or are you sleeptyping as a side effect of the Ambien again?

G.

I wish I had ambien. what am I missing?

 

[FALKEN]

oh; ok;

I think I know where I lost you.

what I mean is that even the low-level material in the signal is attentuated. so say you have a quiet bass line with a loud vocal. when the vocal gets smacked by the limiter, so does the bass.

if you just clip the signal instead. the bass will stay put and only the vocal will get wacked.

get it ?

 

[Reggie]

well....I'm thinking you have heard some bad limiter usage that turned you sour at some point. Smacking a vocal against the final brickwall digital limiter is not going to give a good sound. I tend to use a limiter to catch those ultra fast transients that seem to appear when recording to a digital medium, that are too fast to actually hear as a dynamic part; and occassionally hold down the drums when things get out of hand on a big part or something. Pushing any kind of continuous sound into a limiter is just bad. And not good.
And as far as release times, typically the shorter the crappier. On those fast things I was talking about, you typically won't notice. But fast release times will totally crappy-up your music if you are pushing into it very much at all.
That is why I like UA's Precision Lim. It has an Auto release function that is very good for full mix material. goes fast on the fast stuff, and slower on the slow stuff.

Clipping the signal can actually work in low doses and certain circumstances through certain convertors, but squaring off too many sound waves can really dull down a mix (square waves don't work so hot coming through speakers; not very efficient). And about the only time I have heard clipping not suck is to get the tops of the snare or maybe toms. Kick=crap, guitars=crap, vox=crap, bass=crap when digitally clipped even a little. Or were you talking analog clipping?

 

[FALKEN]

nice post.

I was talking about any clipping. you were talking about

If you can even hear (let alone hear it sound like poo) something like the Universal Audio Precision Limiter working to catch occassional stray peaks, I will give you a cookie.

and

You probably don't even like the sound of tape softening the transients either. Freak!

so I pointed out the difference between limiting (or compression) and clipping (or drive).

 

[SouthSIDE Glen]

the way a limiter works is when the signal exceeds the threshold, a gain reduction is applied. meaning the whole signal is attentuated, not just the peaks.

Falken,

I gave it a day, almost sure that someone else was going to call you on this one. I can't believe no one has yet.

A limiter is little more than an extreme version of a compressor, and limiters do nothing intentional to the signal below the threshold. You describe them as though they work like a ducking attenuator, which is erroneous.

say you have a quiet bass line with a loud vocal. when the vocal gets smacked by the limiter, so does the bass.

Only if the level of the bass exceeds the threshold as well.

In fact, with a limiter or a compressor, if makeup gain is used on the output stage, low level bass is usually boosted after gain reduction is applied to high frequency peaks. The reason is that the dynamic range between the HF peaks and the under-threshold bass is reduced by the gain reduction. So when makeup gain is used, the HF stuff is brought back up to it's old levels and the LF stuff is boosted to levels higher than they were before. If there is a brick wall limit thrown up just to avoid clipping, however, no makeup gain is applied, and the below-threshold stuff just stays where it is.

G.

 

[Reggie]

Falken,

I gave it a day, almost sure that someone else was going to call you on this one. I can't believe no one has yet.

A limiter is little more than an extreme version of a compressor, and limiters do nothing intentional to the signal below the threshold. You describe them as though they work like a ducking attenuator, which is erroneous.

Only if the level of the bass exceeds the threshold as well.

Yeah, I was thinking on this but didn't want to say anything because I wasn't sure. I think it may depend on the limiter. I have heard things that sound like ducking when pushed hard. Just not too sure...
No I guess you are right, at least it should be infinity:1 ratio of compression happening at the selected threshhold (peak value).
It's still early

 

[SouthSIDE Glen]

I have heard things that sound like ducking when pushed hard.

If I had to guess, I would think maybe those were instances where the limiting threshold was low enough to attenuate most of the signal and not just throw up a clipping wall.

If a track's pre-limiting RMS is (just to grab arbitrary numbers) -14dBFS with average peaks that go to, say, -6dBFS and transient peaks that approach 0dBFS, if one throws a limiter in at, say, -12dBFS, the overall RMS level of the signal will indeed go down and one will hear a drop in volume.

How often is this done? Or at least how often is it done without applying makeup gain to get the volume back? Or, if the intent is indeed meant to drop the volume by squashing the signal at a low threshold like that, how often is it done via limiting instead of "regular" compression?

And even it it is done (which I'm sure it is on special occasions), that is an entirely different animal than what you guys were discussing, which was limiting vs. clipping at or near the 0dB threshold level.

G.

 

[FALKEN]

glen,

no matter where the threshold is the same mechanism is still at work.

which is a gain reduction circuit that is dependent on voltage as the input variable.

compression or limiting, when voltage crosses the threshold a gain reduction is applied.

when the instance of voltage crosses the threshold, it is reduced. period.

in that instant where the gain reduction is applied, there is no way that it could affect only the material above the threshold, and not the material below the threshold.

both high and low volume material are respresented by the same instance of voltage.

this is why multitracks were invented.

in fact, this is the most likely reason for the title of this thread.

as the snare or vocals or whatever is crossing the threshold, the cymbals are being affected, too.

 

[SouthSIDE Glen]

when the instance of voltage crosses the threshold, it is reduced. period.

True.

in that instant where the gain reduction is applied, there is no way that it could affect only the material above the threshold, and not the material below the threshold.

both high and low volume material are respresented by the same instance of voltage.

Welll, true as far as it goes, in that there is just one single voltage signal on which all the waveforms are superimposed regardless of frequency. Not quite so true in the analysis of how everything is affected.

If you have a 100Hz sine wave coming in at a peak amplitude of, say, -10dBFS, and then you modulate it with a high frequency snare hit that momentarily takes the peak amplitude up to, say, -3dBFS, all that is happening to the bass waveform is that it is being "modulated" by the snare; it is being "distorted". Throw in a limiter or compressor at a threshold of -6dBFS and the "distortion" (i.e. the snare hit) is attenuated above the threshold, but the underlying 100 Hz sine wave is not touched other than the amount of distortion overlayed upon the sine wave is reduced. The dynamic range between the 100Hz signal and the snare hit is reduced, but the level of the bass frequency remains unchanged at -10dBFS.

G.

 

[FALKEN]

The dynamic range between the 100Hz signal and the snare hit is reduced, but the level of the bass frequency remains unchanged at -10dBFS.

I disagree. Both the snare hit and the bass are reduced by the same amount. at any instance of time, the gain reduction has no way of knowing that the bass and the snare are not the same signal. it cannot reduce one part of a signal but not another. the signal cannot even be broken up into parts like this. it is just the sginal. either it is attentuated, or it isn't.

 

[Reggie]

OK, I'm coming around. I just did a quicky test in Cubase using a -10db 125Hz tone and a zero db 1000 tone. I had Voxengo Span on the output watching the levels of the different tones. As I dropped the threshold down on the limiter (just the Dynamics plug) below zero, both tones are reduced in volume, even though the -10 tone is still below the threshold. I mean, I guess it only makes sense; but I never really put much thought into it. A compressor won't really do this as much because it is only reducing the ratio at which audio passes over its threshold; it never actually holds anything completely down (like reducing the threshold on a limiter just pushes everything down) - just keeps audio from going up quite so high. I don't think I am wording very well here, but you know what I'm saying?

And I'll be danged but it works the other way too in case your curiousity isn't satisfied: leaving the limiter threshold set and leaving the -10 125Hz tone at a set volume, I raised the volume of the 1K tone into and above the threshold; and by golly the 125 tone was reduced in volume.

 

[SouthSIDE Glen]

the gain reduction has no way of knowing that the bass and the snare are not the same signal.

If taht were true, there'd be no way to make MBCs!

But that's beside the point. Maybe this will help from a different direction. Frequency, by it's very definition, cannot be defined or determined by a single voltage at a single point in time, it can only be defined by the length of it's wave (or it's frequency over time). If the amplitude of a wave is below the threshold, the wave's amplitude, and therefore the volume of that frequency of sound, will not be affected. If you have waves of other frequencies whose peaks DO rise above the threshold, those frequencies will be affected.

The fact that a snare may move the voltage/waveform above the threshold does not mean that the bass frequency is pushed above the threshold, it only means that there is another waveform superimposed upon the bass wave and that superimposition is temporarily pushing the voltage above the threshold, but it is doing so at a different frequency than that of the bass signal.

G.

 

[Reggie]

If what you say were true, there'd be no way to make MBCs!

But that's beside the point. Maybe this will help from a different direction. Frequency, by it's very definition, cannot be defined or determined by a single voltage at a single point in time, it can only be defined by the length of it's wave (or it's frequency over time). If the amplitude of a wave is below the threshold, the wave's amplitude, and therefore the volume of that frequency of sound, will not be affected. If you have waves of other frequencies whose peaks DO rise above the threshold, those frequencies will be affected.

The fact that a snare may move the voltage/waveform above the threshold does not mean that the bass frequency is pushed above the threshold, it only means that there is another waveform superimposed upon the bass wave and that superimposition is temporarily pushing the voltage above the threshold, but it is doing so at a different frequency than that of the bass signal.

G.

Well, no, MBC's DO do what you are saying, but only by breaking up the audio signal into separate band-limited signals where compression can be applied independently. Sorry to gang up on you now; but good discussion.

 

[Farview]

But that's beside the point. Maybe this will help from a different direction. Frequency, by it's very definition, cannot be defined or determined by a single voltage at a single point in time, it can only be defined by the length of it's wave (or it's frequency over time). If the amplitude of a wave is below the threshold, the wave's amplitude, and therefore the volume of that frequency of sound, will not be affected. If you have waves of other frequencies whose peaks DO rise above the threshold, those frequencies will be affected.

The fact that a snare may move the voltage/waveform above the threshold does not mean that the bass frequency is pushed above the threshold, it only means that there is another waveform superimposed upon the bass wave and that superimposition is temporarily pushing the voltage above the threshold, but it is doing so at a different frequency than that of the bass signal.

G.

It only works this way if you assume that the limiter rebounds faster than the wavelength of the lower tone.

 

[Reggie]

It only works this way if you assume that the limiter rebounds faster than the wavelength of the lower tone.

Nice! Hadn't considered that angle yet. Now it's getting really confusing.

 

[SouthSIDE Glen]

Well, Reggie, I have to respect experimental data. I haven't tried your expiriment myself, but I'll accept your results. There's still a disconnect, however. I'll have to think about this a bit...if I am wrong, it sure would not be the first time!

I'd be interested to see what happens if instead of a continuous 1k tone you threw in a 1k burst.

G.

 

[Reggie]

I'm guessing something like this might happen:

It only works this way if you assume that the limiter rebounds faster than the wavelength of the lower tone.

quicker, higher freq stuff won't really mess with the low end much to matter. But doing the nasty, continuous limiter mashing that Falken is familiar with will end up with pushing down the low end and whatever else.

Edit: right, depending on limiter release timing

 

[Farview]

I'd be interested to see what happens if instead of a continuous 1k tone you threw in a 1k burst.

G.

The limiter would attenuate the signal and you would see the low frequency signal return to it's original volume after the burst. It will take what ever amount of time you set as the release time to return.