Why don't some software filters display cutoff frequency values?

[Functional]

Recently I went over my filter collection because I'm trying out various filters for a setup I made which work with either any bandpass filter or a filter that allows to run lowpass and bandpass in serial.

Normally, I wouldn't care about the particular frequency value of a filter. But, for my particular setup, I actually care about it. One could imagine an array kind of like a filterbank.

The biggest (and by far) offender in this category was interestingly enough... Audio Damage, after trying their FilterStation 2 (because it has the 914 filter which would be ideal for this). But, not only does it not display a frequency value, it also does not display the peak / resonance value. In fact, you use the same X/Y pad interface to adjust both, which makes finetuning frequency without affecting the resonance extremely hard. And on top of this, since you cannot see frequency value itself, you'd have to use a frequency analyzer and set the peak up the wazoo.

...which has left me to wonder, why? I made the setup initially with FabFilter Volcano. There, not only the frequency value is displayed, I can directly adjust it by typing the value I want.

Is it that much more work to be able to display the frequency value or what is the reason for this? I can understand old emulations of something like Moog filter (if such exist) since back then everyone was used to knobs. But apparently this is still a thing

[AnX]

why would you need that?

[Functional]

why would you need that?

For example, to replicate fixed filterbank. But more importantly, to try out multiple different filters in the same setting and how they work

[Forgotten]

Probably because most people would use their ears to compare I would guess?

[Functional]

Probably because most people would use their ears to compare I would guess?

Try figuring out with your ears whenever a 6db/oct slope bpf filter is at 200hz or 300hz. Hats off if you can do it, but I certainly can't

[Forgotten]

Probably because most people would use their ears to compare I would guess?

Try figuring out with your ears whenever a 6db/oct slope bpf filter is at 200hz or 300hz. Hats off if you can do it, but I certainly can't

If you're doing an A/B comparison you should be able to hear it.

[Functional]

If you're doing an A/B comparison you should be able to hear it.

Uh, A/B'ing 8 channels (as in, go through the tedious process 8 times to get to the end result)? Or, just you know, have a value displayed for convenience. Just like I would be able to make envelope filters with any parametric EQ and automation, but for the sake of convenience, I'd rather have my synths have envelopes for that.

Point is, I can't imagine the freq value display to be really that much work for it to not be included for convenience

[Forgotten]

I don't really ever think about what the absolute value of a cutoff filter is, I just listen to it and know if it's where I want it or not. I kind of thought other people did that too. I can't really think of another reason why it's not displayed most of the time.

[Functional]

Yeah I do get that, it's probably the simplest answer unless there's something DSP-wise that I'm unaware of (and there shouldn't be). But Audio Damage FilterStation 2 made me roll my eyes in particular because it's the same outlet that actually has the AD914 fixed filterbank. Maybe they made it on purpose, so you'd have hard time recreating that filterbank precisely (cause it truly is extremely hard)

[ghettosynth]

Here's the reason: it's more work. You have to put some widget on the panel that shows the frequency and then map whatever the control generates back to frequency. Sometimes that's trivial, but, most often your control will not map directly to frequency but to some linear scale, e.g., volts, pitch, 0-1, and so you then have to use whatever function you're using to compute frequency values to obtain the correct value for the display. That's not usually a big deal, but it might require some minor refactoring. Further, you now have to format it. The dsp code that takes a double doesn't care how many numbers are past the decimal point, but your customer doesn't want to see all of that. That formatting and the display of it could lead to new bugs and more things for your customer to complain about. Like all things software, every feature has a real cost and if your customers don't demand it, then that's time that you could spend implementing some other feature and debugging existing ones.

I like this feature too, and even like it when they go further and give you a choice of units to display, e.g., the Ampere modules for Reaktor. But, I would think that the main market for filter plugins is performance and so the majority of customers are just using their ear to tune the filters.

[Functional]

Here's the reason: it's more work. You have to put some widget on the panel that shows the frequency and then map whatever the control generates back to frequency. Sometimes that's trivial, but, most often your control will not map directly to frequency but to some linear scale, e.g., volts, pitch, 0-1, and so you then have to use whatever function you're using to compute frequency values to obtain the correct value for the display. That's not usually a big deal, but it might require some minor refactoring. Further, you now have to format it. The dsp code that takes a double doesn't care how many numbers are passed the decimal point, but your customer doesn't want to see all of that. That formatting and the display of it could lead to new bugs and more things for your customer to complain about. Like all things software, every feature has a real cost and if your customers don't demand it, then that's time that you could spend implementing some other feature and debugging existing ones.

I like this feature too, and even like it when they go further and give you a choice of units to display, e.g., the Ampere modules for Reaktor. But, I would think that the main market for filter plugins is performance and so the majority of customers are just using their ear to tune the filters.

Right, this makes sense. Guess I'll have to live with it, at least Volcano does pretty much exactly what I want

[Benedict]

You can use a spectrum analizer(!) to see where your signal is rolling off.

But while readouts are nice (assuming they are reasonably accurate) your ears+ brain are the real things to develop. If you become conscious about the things you observe, it will creep up on you and you'll suddenly find yourself saying something like, oh that could use a bit of a kick a 350Hz.

That comes from your brain creating a sort of spreadsheet of all the things you observe if you let it. Conversely, having an "I'll never know" approach this tells your mind to ignore or tag all info as useless.

[chk071]

The problem with frequency display IMO is that, once you modulate the cutoff, it will simply become useless. It's only ever useful, when the cutoff isn't modulate, and when you change the cutoff parameter. In any other case, it is not very helpful, IMO.

And, on a synth like Sylenth1, which has a cutoff per filter, and a global cutoff parameter, it's even double useless.

[Functional]

The problem with frequency display IMO is that, once you modulate the cutoff, it will simply become useless. It's only ever useful, when the cutoff isn't modulate, and when you change the cutoff parameter. In any other case, it is not very helpful, IMO.

And, on a synth like Sylenth1, which has a cutoff per filter, and a global cutoff parameter, it's even double useless.

Yeah but you don't have to necessarily modulate the cutoff, you can modulate the output signal otherwise. Or you can modulate the cutoff but in a way where precision isn't as important.

Honestly I think I should just move to Reaktor, seems like everything I would want is in Reaktor Blocks

[ghettosynth]

The problem with frequency display IMO is that, once you modulate the cutoff, it will simply become useless. It's only ever useful, when the cutoff isn't modulate, and when you change the cutoff parameter. In any other case, it is not very helpful, IMO.

And, on a synth like Sylenth1, which has a cutoff per filter, and a global cutoff parameter, it's even double useless.

All true, but, that doesn't mean that you can't display the current static setting of the cutoff frequency. Kurzweil made a big deal about this kind of information being available to the musician with the K2X series stuff. It goes without saying that modulation changes the values and that they are not the same, per voice, but, if you're using a filter as part of a filterbank then you are typically not modulating it, but also, it's not so much about realtime feedback of what the cutoff frequency currently is at any moment, but what its base value is prior to modulation. In that sense, the fact that a synth is a polysynth is immaterial.