Thank you for this much needed vid. I suspected this is the case with sidechain filtering, but having you explain it was so important to me :) Thanks so much
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the way i go about setting up the mixbus compressor is to zero out my compressor, set the threshold and then the attack and release settings. After this i get the compression going which i judge by the movement of the VU Meter's needle. However, immediately i start egaging the sidechain filter, the needle's movements change or it stops. At this point am i still getting c ompression? Now, to get the needle wagging again so i can judge the amount of compression i'm getting, i start resetting the Threshold; is this correct? I ask this because resetting the threshold to see the needle wag means disrupting the threshold setting that i so painstakingly set. Now once i get the needle moving with the new threshold settings and i adjust and get the compression that I want, do i leave the Threshold at the new setting or return it to the previous setting before i engaged the sidechain filters on the compressor?
Good question. Well, you have 2 options: Option A - Use a compressor with a side-chain filter eq OR Option B - Use pre and post eqs. Pre eq to get the compressor to react how you want by boosting/cutting and then Post- EQ to restore the desired tonal balance. I'd suggest using linear phase EQ for Option B if pre-ringing is not a big issue and the eq moves are small. The bigger question I have for you is: Why do you need access to the side-chain filter? What task is it for?
The why is exactly what you're explaining here. We would like to compress the drum bus without affecting the lower frequencies. For some reason Waves G-Bus doesn't come with a HPF to bypass the low freqs as it compresses. Option B you explained though, if I'm understanding it correctly, kind of sounds like you might lose information or quality in trying to manipulate it with a post EQ to get the sound back to where it started. Is there not a simpler method? Perhaps sending the drum bus signal to a separate bus to HPF it there before applying the bus compressor on that new bus? @@SPLMixing
Very informative! By the way, have you had any experience in using sidechain LOW-pass filters, or for that matter, sidechain filters when using a gate/expander??? If so, what would be the best applications for such filters???
Yes, I have. Only in a special circumstances where I can't find what I am looking for from the compressor or gate. Listening to the Side-Chain helps you there too. Sometimes I will send a highly modified copy of an existing track into a Side-Chain, so modified they only are used for this purpose, and never actually heard by the listener. I call these ghost Side-Chain tracks.
So one might say this technique is used to preserve frequencies? Like int the case of compressing a metal guitar riff. You want to target certain transients without losing low frequency energy?
Depending on how they're driven, some compressors may eat up some frequencies more than others. There's no one-size-fits-all answer here. If you want to target the compression of certain frequencies specifically, then you're better off using multi-band compression or a dynamic EQ for that. In the case that I show, using a broad-band compressor like the SSL, filtering the side-chain adjusts the amount of compression by taking away frequencies that might otherwise make the compressor react unfavourably to what it is you're trying to make the compressor do. For instance, if the compressor normally compresses heavily (reacts a lot or abruptly) on bass tones present in the audio, then taking those out of the side-chain has the benefit of smoothing out the overall reactions of the compressor to be less abrupt or heavy. The side-chain is only heard by the compressor and therefore is not something we necessarily perceive as a change in tone, in the same manner we would hear a tonal change when adjusting an EQ. You might hear a tonal change as a result of the change in compression behaviour, however, that's getting into a lot of the subtle nuances of compression and how we might use them in other musical ways.
Nice explanation. The SSL plugin has a helpful A/B switch. Try this: Set to A. Attack=1ms, release=0.1s, ratio=4 Run a full mix through it with no SC filter and dial in threshold for 8dB of peak compression. Use a song with a decent bass and kick drum groove. Then switch to B and set everything the same as A but run the SC up to 120Hz. Next adjust the threshold down to get the SAME peak of 8dB compression. Now A/B/A/B... Do you notice any difference in the character of the low-end? I think it plays with the feeling of low-end punch and sustain, even though it is just full band compression. Perhaps this is a cause behind any confusion or myth.
Yes, I think you're 100% right. That's getting into the finer nuances of what a compressor does. I agree there is a certain degree of frequency dependant compression applied, and that the ratio application is never completely linear across all frequencies - especially in analogue modelled plugins like the SSL Bus Comp. I thought about explaining that aspect, but I know a lot of beginners will find that confusing when they're trying to grasp the basic concepts of SC filtering. But you're absolutely right, there's more to it going on under the hood.
To reduce boominess in the bass, your first step would be eq, either low shelf, high pass filter, bell filter... The purpose of using the high pass filter on the compressor is to stop it hearing and reacting to low bass frequencies that might otherwise push the compressor too hard. The high pass on a compressor only affects what the compressor hears, not what we hear. Does that clear things up?
Hi@@SPLMixing OK. I get it now... I completely misunderstood because I guess I wasn't really listening after all. I was mixing up EQ with Compressor. Thank you so much for getting back to me! Paul
Is the purpose of doing this to get a better idea of how the compressor is affecting the frequencies above the cutoff point? I understand your explanation, but the purpose is a bit unclear. Thank you.
The purpose of using the side-chain high pass is to change the operation of the compressor, to allow it to ignore bottom end information that might be triggering the processing unit too much. The purpose of the video is to explain that it doesn't suddenly make the compressor dual band, or stops the compressor from compressing the lows. The side-chain signal is simply a parallel copy of the original signal; we hear the original signal and the compressor hears the copy (side-chain). Changing what the compressor hears doesn't necessarily change what frequencies get compressed.
What I explain in the video has nothing to do with perception, it's about understanding the fundamentals of how a compressor works. The resulting tone could skew more low-centric, and in most cases it will, but this depends on how the compressor is reacting to the bandwidth limited signal in the sidechain. Not all compressors will react the same way and it depends greatly on the nature of the signal that's left in the sidechain. But don't believe me, we just met, try it out for yourself.
This is a really important difference thanks for highlighting this 👍
Thank you for this much needed vid. I suspected this is the case with sidechain filtering, but having you explain it was so important to me :)
Thanks so much
Thanks for posting this
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Thanks! This was really helpful and cleared things up for me
Glad to hear it!
Great explanation ! Thanks bro !
Great explanation
Thanks for some great information!!
Thank you
the way i go about setting up the mixbus compressor is to zero out my compressor, set the threshold and then the attack and release settings. After this i get the compression going which i judge by the movement of the VU Meter's needle. However, immediately i start egaging the sidechain filter, the needle's movements change or it stops. At this point am i still getting c ompression?
Now, to get the needle wagging again so i can judge the amount of compression i'm getting, i start resetting the Threshold; is this correct?
I ask this because resetting the threshold to see the needle wag means disrupting the threshold setting that i so painstakingly set. Now once i get the needle moving with the new threshold settings and i adjust and get the compression that I want, do i leave the Threshold at the new setting or return it to the previous setting before i engaged the sidechain filters on the compressor?
you look good in this light and perspective ..
Thanks! I've been putting in a lot of work to improve the visuals
How to use sidechain filter eq when we don't have sidechain filter eq? Like we don't have sidechain filter in waves bus compressor?
Good question. Well, you have 2 options:
Option A - Use a compressor with a side-chain filter eq OR Option B - Use pre and post eqs. Pre eq to get the compressor to react how you want by boosting/cutting and then Post- EQ to restore the desired tonal balance. I'd suggest using linear phase EQ for Option B if pre-ringing is not a big issue and the eq moves are small. The bigger question I have for you is: Why do you need access to the side-chain filter? What task is it for?
The why is exactly what you're explaining here. We would like to compress the drum bus without affecting the lower frequencies. For some reason Waves G-Bus doesn't come with a HPF to bypass the low freqs as it compresses. Option B you explained though, if I'm understanding it correctly, kind of sounds like you might lose information or quality in trying to manipulate it with a post EQ to get the sound back to where it started. Is there not a simpler method? Perhaps sending the drum bus signal to a separate bus to HPF it there before applying the bus compressor on that new bus? @@SPLMixing
Very informative! By the way, have you had any experience in using sidechain LOW-pass filters, or for that matter, sidechain filters when using a gate/expander??? If so, what would be the best applications for such filters???
Yes, I have. Only in a special circumstances where I can't find what I am looking for from the compressor or gate. Listening to the Side-Chain helps you there too. Sometimes I will send a highly modified copy of an existing track into a Side-Chain, so modified they only are used for this purpose, and never actually heard by the listener. I call these ghost Side-Chain tracks.
So one might say this technique is used to preserve frequencies? Like int the case of compressing a metal guitar riff. You want to target certain transients without losing low frequency energy?
Depending on how they're driven, some compressors may eat up some frequencies more than others. There's no one-size-fits-all answer here. If you want to target the compression of certain frequencies specifically, then you're better off using multi-band compression or a dynamic EQ for that. In the case that I show, using a broad-band compressor like the SSL, filtering the side-chain adjusts the amount of compression by taking away frequencies that might otherwise make the compressor react unfavourably to what it is you're trying to make the compressor do. For instance, if the compressor normally compresses heavily (reacts a lot or abruptly) on bass tones present in the audio, then taking those out of the side-chain has the benefit of smoothing out the overall reactions of the compressor to be less abrupt or heavy. The side-chain is only heard by the compressor and therefore is not something we necessarily perceive as a change in tone, in the same manner we would hear a tonal change when adjusting an EQ. You might hear a tonal change as a result of the change in compression behaviour, however, that's getting into a lot of the subtle nuances of compression and how we might use them in other musical ways.
thats what i like. thank you
Glad you like it!
Nice explanation.
The SSL plugin has a helpful A/B switch. Try this:
Set to A. Attack=1ms, release=0.1s, ratio=4
Run a full mix through it with no SC filter and dial in threshold for 8dB of peak compression.
Use a song with a decent bass and kick drum groove.
Then switch to B and set everything the same as A but run the SC up to 120Hz. Next adjust the threshold
down to get the SAME peak of 8dB compression.
Now A/B/A/B...
Do you notice any difference in the character of the low-end?
I think it plays with the feeling of low-end punch and sustain, even though it is just full band compression.
Perhaps this is a cause behind any confusion or myth.
Yes, I think you're 100% right. That's getting into the finer nuances of what a compressor does. I agree there is a certain degree of frequency dependant compression applied, and that the ratio application is never completely linear across all frequencies - especially in analogue modelled plugins like the SSL Bus Comp. I thought about explaining that aspect, but I know a lot of beginners will find that confusing when they're trying to grasp the basic concepts of SC filtering. But you're absolutely right, there's more to it going on under the hood.
i’m still waiting for Eddy Grant to say “heeeey”
Sorry, but after watching your video twice I still don't get what you mean. How are we supposed to reduce boominess in the bass then?
To reduce boominess in the bass, your first step would be eq, either low shelf, high pass filter, bell filter...
The purpose of using the high pass filter on the compressor is to stop it hearing and reacting to low bass frequencies that might otherwise push the compressor too hard. The high pass on a compressor only affects what the compressor hears, not what we hear.
Does that clear things up?
Hi@@SPLMixing OK. I get it now... I completely misunderstood because I guess I wasn't really listening after all. I was mixing up EQ with Compressor. Thank you so much for getting back to me! Paul
Is the purpose of doing this to get a better idea of how the compressor is affecting the frequencies above the cutoff point? I understand your explanation, but the purpose is a bit unclear. Thank you.
The purpose of using the side-chain high pass is to change the operation of the compressor, to allow it to ignore bottom end information that might be triggering the processing unit too much. The purpose of the video is to explain that it doesn't suddenly make the compressor dual band, or stops the compressor from compressing the lows. The side-chain signal is simply a parallel copy of the original signal; we hear the original signal and the compressor hears the copy (side-chain). Changing what the compressor hears doesn't necessarily change what frequencies get compressed.
Yes but inturn more 'Perceived' low end is coming thru. Pretty sure Pro's understand this
What I explain in the video has nothing to do with perception, it's about understanding the fundamentals of how a compressor works. The resulting tone could skew more low-centric, and in most cases it will, but this depends on how the compressor is reacting to the bandwidth limited signal in the sidechain. Not all compressors will react the same way and it depends greatly on the nature of the signal that's left in the sidechain. But don't believe me, we just met, try it out for yourself.