Suggestions sought - using PC or Mac as a crossover with some added complexities

[Olli]

What about this: https://rogueamoeba.com/audiohijack/

 

[Krunok]

Oh awesome

I’m going to research and think through this a little more and eventually likely hit you up about this...

What can be implemented now via BruteFIR plugin for Volumio is not only dynamic EQ feature you desccribed but also a feature implemented in Devialet SAM where different filters with higher bass extension are activated as volume raises to keep woofer from excessive excursion.

 

[andreasmaaan]

Keep us posted Andreas, as I'll want to use the same pathway as you for my project:
PC with a OS --> Spotify/Tidal/VLC/Kodi/Firefox --> A system-wide EQ (Room EQ) --> Digital XO (FIR) --> Multichannel Dac --> separate amps.

Will do

 

[andreasmaaan]

What about this: https://rogueamoeba.com/audiohijack/

View attachment 28259

Thanks! I still haven’t found a software crossover for Mac, but this is a good start.

 

[Biblob]

For Linux, my guess is there is no limit when customising Pulse Audio to your likings.
A readymade software for crossovers and EQ example:
https://t-5.eu/hp/Software/Pulseaudio Crossover Rack/

 

[andreasmaaan]

For Linux, my guess is there is no limit when customising Pulse Audio to your likings.
A readymade software for crossovers and EQ example:
https://t-5.eu/hp/Software/Pulseaudio Crossover Rack/

Thanks but link seems to be busted....

 

[Biblob]

I notice it too. Must be very recently. Looked at it couple of days ago.

 

[andreasmaaan]

I notice it too. Must be very recently. Looked at it couple of days ago.

Hopefully just temporary then

 

[somebodyelse]

Link worked just now for me.

 

[Biblob]

Ah yes. It's back again. Maybe an update

 

[somebodyelse]

BrutefirDrc (a plugin for logitechmediaserver to do the convolution on the server end) did loudness by piping the audio from the virtual sound card through sox loudness function before passing it on to brutefir.

 

[DDF]

There's always the Bozio ultimate equalizer. Very high functionality including 4+ way xovers, phase EQ and low frequency room eq
http://www.musicanddesign.com/Ultimate_Equalizer_promo.html

Experienced DIYers report good success (eg DLR here):
http://techtalk.parts-express.com/f...-running-on-pc-platform?p=1114573#post1114573

The Bozio SW UI is reputed to be a chamber of horrors so I've yet to take the plunge.

Edit: one more option, though I've not come across any feedback:
http://www.thuneau.com/allocator.htm

 

[Olli]

Thanks! I still haven’t found a software crossover for Mac, but this is a good start.

Andreas, you can generate XO and Filters on a windows machine (eg w/ Audiolense) and use just any convolver on a Mac or PC. I use Roon on a Mac, for example.

With Loopback you can run any source - Browser-, App- or Hardwarebased. So you could even route your Turntable through if your DAC has an analogue input.

Just found something that seems to be the equivalent for Windows: https://www.vb-audio.com/Cable/

 

[andreasmaaan]

Thanks everyone. Lots of interesting ideas to follow up on here

 

[Krunok]

In short, it's EQ that is only activated when the input drops below (or above) a certain threshold level. In this case, it would be used to boost low frequencies when the volume dropped below a certain threshold, to compensate for the hearing system's nonlinearity (equal loudness curves).

How many volume levels/fitler sets do you think a system should have to effectively implement dynaimc EQ (loudness + LF reduction on high volumes)?

 

[andreasmaaan]

How many volume levels/fitler sets do you think a system should have to effectively implement dynaimc EQ (loudness + LF reduction on high volumes)?

Ideally, it isn't discrete at all.

For example, this is a dynamic EQ VST plugin set up to kick in only when the signal drops below -20dBfs (the "threshold"). The magnitude of the bass boost is then inversely proportional to the level of the input, so that at -20dBfs the boost is 0dB, and at -X dBfs the boost is +18dB (this is just an example btw, it's not supposed to be correct necessarily):

 

[Krunok]

Ideally, it isn't discrete at all.

For example, this is a dynamic EQ VST plugin set up to kick in only when the signal drops below -20dBfs (the "threshold"). The magnitude of the bass boost is then inversely proportional to the level of the input, so that at -20dBfs the boost is 0dB, and at -X dBfs the boost is +18dB (this is just an example btw, it's not supposed to be correct necessarily):

View attachment 28416

Heh, I know it would be best if it isn't discrete, but with BruteFIR it can only be implemented by changing the filters based on volume change. I am basically asking for your opinion what do you think would be a "reasonable" number of filters to implement in that scenario? It is also a question how many filters would folks be willing to generate in order to achieve such functionality..

 

[andreasmaaan]

Heh, I know it would be best if it isn't discrete, but with BruteFIR it can only be implemented by changing the filters based on volume change. I am basically asking for your opinion what do you think would be a "reasonable" number of filters to implement in that scenario? It is also a question how many filters would folks be willing to generate in order to achieve such functionality..

Fair enough In that case, I'm not sure, will have to think it through. Perhaps others have thought about it already? Maybe 4 would be "enough"?

 

[Krunok]

Fair enough In that case, I'm not sure, will have to think it through. Perhaps others have thought about it already? Maybe 4 would be "enough"?

I was thinking about 5.

So, is yellow line on your graph for quiet playing and blue line for very loud?

 

[andreasmaaan]

I was thinking about 5.

So, is yellow line on your graph for quiet playing and blue line for very loud?

Not quite, no. Above -20dBfs, the output is flat. Below -20dBfs, the output gets closer and closer to the yellow curve, reaching it at a level determined by the "ratio" setting.