Pulse Effects - a limiter for bass?

[krauster]

I posted this on a Linux Mint forum hoping to find an answer. Maybe I'll have better success here in this LinuxMusicians forum because it is about audio plugins:

Mint 20.

I loaded from the Software Manager, Pulse Effects and PulseAudio Volume Control.

I have loaded Pulse Effects because I wanted an equalizer. I have some cheap Logitech speakers - two little left and right speakers and a sub that I have turned off. I have the subs turned off because I live in a condo with shared walls and am trying to set a good example for my neighbors, and I just don't like deep base anyway. But even with the sub turned off there is too much bass coming from the little speakers. So I've got the equalizer working in Pulse Effects.

It's a 30 band equalizer by default. I have lowered the lowest 5 bands, 23Hz, 28Hz, 36Hz, 45Hz and 57Hz, setting it to -25, -19, -15, -11, - 7, respectively.
This works well for the one tune I was playing when I made these settings.

But all music is mixed differently and some music doesn't have deep base and doesn't need base attenuation. What I really need is a bass limiter so that any audio gets reduced bass when needed and the songs with lots of bass gets the bass attenuated more than the stuff that doesn't have a lot bass, where I don't need to be attenuating the bass at all.

I don't see this type of setting in the different modules of Pulse Effects. I do see Limiter, Auto Gain, Compressor, Multi-band Compressor, etc but I don't understand those settings. Does anybody know which module and what specific setting category in that module I want to use for a low frequency limiter?

[sysrqer]

What you are looking for is unlikely to be in the standard fx, you're describing a dynamic eq, although perhaps a multiband compressor could work, and this is quite an advanced effect. I don't know anything about pulseaudio effects but I would imagine they don't offer anything like this. However, you could do this with jack.

Jack is another sound server like pulseaudio but it can run as a master with pulseaudio bridged to it. This means that you can take advantage of the modular-ness that jack offers and route pulseaudio through some fx via a plugin host like Carla.

The problem is that there aren't any stereo dynamic EQs (this isn't quite true but you would need to compile something) but there are multiband compressors such as Calf's so you could set it so bass is compressed or limited when it exceeds a threshold.

[varpa]

I just installed Pulse Effects to see what you are talking about. I think you could use the multiband compressor as a bass limiter. Configure the Sub Band to have a high ratio, perhaps 10, so that it become like a limiter. Set the other bands of the multiband to bypass. Put on some bass-heavy music and adjust the sub band threshold and makeup gain to get the amount of bass you like. Possibly lower the attack if there there are bass heavy transients to reduce (like bass drum). You can also adjust the frequency range for the sub band which I see is 120 Hz by default.

[Death]

First of all, if they're little speakers then there wont be much low end on them. What you're hearing might be more around the 200-250Hz area which helps give the impression of more bass on small speakers.

Anyway, what you want is a multiband limiter. You want to set it up so that only the low band is doing anything. Failing that, just use the multiband compressor you mentioned. A multiband compressor and dynamic EQ are essentially the same tool, by the way. A dynamic EQ is just more specific with its shapes. Are you any good at setting up compressors/limiters?

[sunrat]

The Multiband Compressor in PulseEffects should do what you want. I find the interface a little confusing for some modules but if you put the right numbers in it will work ok.
Someone mentioned a dynamic EQ above. The free TDR Nova has become one of my favourite EQs lately and can work as dynamic or standard parametric. It's a Windows VST2 but works perfectly with LinVST. May require JACK and a plugin host like jalv or Carla.
For PulseAudio and no JACK, PulseEffects is just about the only choice I know of.

[krauster]

First of all, if they're little speakers then there wont be much low end on them. What you're hearing might be more around the 200-250Hz area which helps give the impression of more bass on small speakers.

Yes, I've been mistaken about this. The sub is in an awkward position under my desk and feeling it with my hands I couldn't feel any vibration. So I pulled out and placed my ear to it and the bass is coming from it. There is no off control on the speaker but there is a bass control on the remote accessory to set the level and I already have it all the way down. Maybe I'll try to at least isolate it from the floor on some foam pads.
EDIT: I was pushing it back under the desk I realized that it does sound way more boomy under there, so I need to make room for it somewhere else. Also I was able to cut it a little stuffing a rag inside the port on the side of it.

But mostly I want to figure out how to use the multiband compressor. I don't understand the settings:

https://imgur.com/RjZ4gJM
In the Sub Band I've played with the ratio and split 1/2 as suggested but I don't hear any difference.

[sunrat]

There's a serious deficiency of information about how to use PulseEffects and those few guides I did find did not even mention the Multiband Compressor.
It's not too hard to use although I don't know what the dropdown LR8/LR4 means.
So you want to limit the Sub band below 120Hz. Reduce the Attack to 20ms and Release to 70ms (may not be perfect but defaults are too high). Play some bass heavy music, the meters should now be moving. Turn the ratio up to 10 for fairly strong limiting. The threshold sets the level at which it kicks in; play with it until you see the Compression meter moving, the momentary level reduction is displayed at the right. Lowering the threshold (ie. higher negative number), raising the ratio, or increasing the input will all increase the compression but keep the input slider so the stereo input meters are green.
Most of these controls will be explained in any Compression 101 tutorial. Limiting is basically the same as compression with a high ratio.

[sysrqer]

LR4 and LR8 will be the steepness of the filters.

[sadko4u]

It seems that Pulseffects still uses Calf multiband compressor.
Calf Multiband Compressor has phasing issues, I would like to recommend to use it carefully since it can give notches at some frequency ranges.

[sunrat]

It seems that Pulseffects still uses Calf multiband compressor.
Calf Multiband Compressor has phasing issues, I would like to recommend to use it carefully since it can give notches at some frequency ranges.

OP asked for a solution using PulseEffects which it is probably the only GUI option. The only other option I can think of is to load a LADSPA plugin using module-ladspa-sink as described here - https://wiki.archlinux.org/index.php/Pu ... ompression but that needs to be configured with a text file. I am aware that Calf plugin may have issues but they would be insignificant through little Logitech computer speakers.
I would suggest using LSP Multiband Compressor in jalv or Carla with JACK for a more sonically accurate solution.
Curiously I wrote that before noticing to whom I was replying. @sadko4u can LSP plugins be loaded as modules in PulseAudio (without JACK) and display their GUI?

[sadko4u]

Currently I have no deal with PulseAudio, sorry. Maybe once I will provide GStreamer wrapper for them but not now. Moving to 1.2.0, porting to Windows and supporting VST3 is in priority.

[sunrat]

Currently I have no deal with PulseAudio, sorry. Maybe once I will provide GStreamer wrapper for them but not now. Moving to 1.2.0, porting to Windows and supporting VST3 is in priority.

Good deal, sensible priorities.
Perhaps the LADSPA version of LSP plugins may be loaded with pulseaudio-module-ladspa but I doubt it supports GUI and I'm not going to test it.
I guess OP will have to use PulseEffects.

[Death]

First of all, this is gonna work a lot better if you watch some tutorials about compressors and practice with them. It's so hard to just throw numbers at people and it expect it to work for their situation. It really takes some experience and know how to do properly. However, I'll throw some numbers at you for you to try until you figure out how to better use the tool yourself

I would watch tutorials on regular broadband compressors rather than multi-band. Multi-band is the same concept, just with the ability to apply different settings to different frequency ranges rather than one setting equally applied to all. Multi-band compressors are more of a repair tool than anything and that's what we're using it for in your case here.

Here's a tutorial video that I found very useful years ago when I was learning about compression. This one just really did it for me while others were confusing the hell out of me: https://invidious.snopyta.org/watch?v=91qs3fux5HY

There are different types of compression - Downwards, upwards & expansion, for example. When people talk about compression and don't specify which type, they're usually talking about downwards compression. This is what we normally work with and this is what we're using here.

First, a note on Attack & Release. If either of these are too fast, the effect can be very unpleasant and distorted. This is even more so with a full mix or on low frequency content. So, slower settings can lead to a more transparent sound. But, sometimes faster settings are better. It's down to experience, know how and goals. In your case, we're just looking to control the level of bass in as transparent a way as possible - we're not looking to create any distortion or effects as much as we can avoid it. For this reason, I will recommend slower settings. Any of these settings can and should be adjusted to taste.

Attack & release: I would suggest starting with the attack on 100ms & the release on 300ms.
Ratio: Start with about 4:1
Knee: Leave at default for now.
Makeup: Leave it at 0. We likely do not want any for our use purpose.
Input & output: Leave at 0. We likely do not want any adjustments for our use purpose.

* Select all of the following bands and enable the 'Bypass' option for them: Low Band, Mid Band, High Band.

* Select the Sub Band.

* Start reducing the Threshold control until you see compression taking place. This should be indicated by the volume meters and will become stronger and more audible as you lower the threshold. For now, get it to a point where about 6-8db of compression (Gain reduction) is happening.

* Now start adjusting the width of the band via the 'Split 1/2' control so you can compress the correct range of frequencies (Use your ears for this). To me this looks like this should be controlling the low point of the Low Band which in turn should adjust the top range of the Sub Band so you'll want to be increasing this setting, probably up to somewhere around 180Hz - 250Hz.

* If nothing changes then it means the Sub Band is fixed and you can't adjust it. So what you'll then have to do is enable the Low Band also (Turn off its bypass control), reset 'Split 1/2' back to 120Hz and give it all the same compression settings as the Sub Band (Attack, Release, Ratio, Threshold etc) and go from there. I can help you more with this but first see if this is even a problem. If the previous step works then you can completely ignore this paragraph!

So now you have your starting point. Watch videos and practice with compressors. Once you understand their controls better, you can tweak your setup and get it sounding right. The method I've steered you towards is using a not so aggressive ratio with a lower threshold because I think it's easier to get to grips with and hear the differences when you're starting out. I also generally compress like this anyway for other reasons. Sometimes it's better to go go the other way round and have a high ratio with a high threshold. There's all different ways to go about it. You can make things sound punchier, fatter, change the tone or even timbre.. Or you can do transparent compression purely for peak control which is what compressors were originally designed for and what we're doing here (Which to be honest is often better done by higher ratio/threshold methods). Again - experience will guide you.

I hope this helps

[sunrat]

First of all, this is gonna work a lot better if you watch some tutorials about compressors and practice with them. It's so hard to just throw numbers at people and it expect it to work for their situation. It really takes some experience and know how to do properly. However, I'll throw some numbers at you for you to try until you figure out how to better use the tool yourself

Thanks for your more detailed explanation. Understanding how compressor/limiters work is indeed key to optimal results. I tested those numbers shown in my posted image and they seemed to work well. Could be totally different for other program material and levels and speakers of course.

* If nothing changes then it means the Sub Band is fixed and you can't adjust it.

What they call "Split" would more usually be called "Crossover Frequency". I'm assuming "Split 1/2" is the crossover frequency between Sub and Low.
PulseEffects is a strange beast with some mysterious settings and sparse documentation. I originally installed it to use it for room correction EQ in PulseAudio but found a much better solution called Pulseaudio Parametric Equalizer - https://t-5.eu/hp/Software/Pulseaudio%2 ... Equalizer/ .

[Toejam76]

I had a similar problem with thin walls. I used a 2nd hand outboard 19" limiter (around 100eur) to prevent my neighbours from lynching me.
Also good on a stero hifi at parties for people who want to play with the volume knob and the computer is not involved.