Hello folks, I've created a simple wide acting Tone Control Filter that can be used in any of your parametric EQ software of choice (details of the filter later in this post).
As a lot of us know there's this thing called "Circle of Confusion" which I think could have been a phrase coined by Toole/Olive to describe the fact that target curves for the audio gear used in the production of any particular piece of music (in the studio) are not an industry standard between all of them.....so this means that some albums / tracks / songs can sometimes sound brighter or duller than they should really be when played back on your headphones or speakers (assuming your headphones and speakers are calibrated close to "neutral/flat"). Toole/Olive therefore say that Tone Controls should be used to tweak to user preference on different music productions for those very reasons. (here's a link to a presentation created by Sean Olive where he practically describes everything Harman re headphones, and there are sections on "Circle of Confusion" in there: https://www.listeninc.com/wp/media/Perception_and_-Measurement_of_Headphones_Sean_Olive.pdf)
So I've created a Tilt Tone Control for headphones & speakers, which is a simple EQ filter that can be implemented in any of your parametric EQ software of choice, this is the filter, it's as simple as this:
High Shelf Filter, 982Hz Q0.2
Here's a pic of it working in action on what happens to be an HE4XX headphone, but note the turquoise shaded area and my drawn in straight red line which is indicating the filter is pretty much acting linearly to tilt the whole frequency response from 100Hz to 20,000Hz:
I've tried out this "tone control" and I find it very effective. For instance, Red Hot Chili Pepper songs I find are generally recorded too bright, so my tone control filter fixes that with just -1 or -2dB on the Gain for that filter, you could probably even try it with just 0.5dB increments. You can easily notice 1dB changes in that filter because it tilts the whole frequency response from 100Hz upwards. High Shelf at 982Hz, Q 0.2 -> that's the filter I urge you to give it a try as a tone control. (that's naught point two for the Q filter, it's a very low Q filter!)
Give it a try if you're curious, and let us know if you find it effective or not. We can also talk about other tone controls you use, other software, plugins, etc.
EDIT: note that particularly with regards to use of this filter with headphones, it's not designed as a way of significantly increasing your bass level of your headphone, because often open-backed headphones roll off the bass early, so in terms of with use with headphones I recommend using my Tone Control Filter alongside a Harman EQ which will already include a Low Shelf Bass Boost filter which often counteracts the phenomenon of this early bass roll-off in open-backed headphones. Yes, so don't use my Tone Control Filter to increase your bass level, use a Low Shelf Filter bass boost or use it with an existing Harman EQ (eg from Oratory) which would already include that bass boost. My Tone Control Filter is used to change overall tonality, not for pumping up the bass specifically, sort the bass out in a different way.
EDIT#2: because my Tilt Control Filter affects so much of the frequency response, don't fall into the trap of the "Loudness Wars" when using positive Gain on my filter, because it will make it sound louder, and often louder sounds better - so instead try to get your mind to pay close attention to the tonality instead, and be aware it can increase the overall perceived loudness if boosted. Also note that you may need to apply a negative preamp alongside my Tone Control Filter if you use positive Gain on my filter - you'll need to do this to avoid digital clipping. However, if you're already using a headphone EQ (eg from Oratory), then you may not need to increase the Negative Preamp because often times the treble area is digitally reduced below 0dBFS in Harman EQ's. The point is.....Whatever EQ you do always check the Total EQ Curve to make sure nothing is creeping above 0dBFS.
EDIT#3: I will also add/emphasise that this Tone Control Filter is not for fixing your headphones, it's for fixing the "Circle of Confusion" in music production, this simple Tone Control Filter will not effectively fix anaemic bass nor piercing treble (or variations on that) in your headphones - fix your headphones first (probably with a Harman EQ) then use this Tone Control Filter as a means for subtley but widely tweaking overall tonality based on the variation ("Circle of Confusion") associated with music production, so this Tone Control Filter is nothing directly related to your headphones, but instead the music creation process itself, hence why you could also use this Tone Control Filter for speakers.
EDIT #4: I tried my Tone Control Filter on my speakers just now, and it works just as well for speakers as it does for headphones. Interestingly I needed the same -2dB Gain for Red Hot Chili Peppers music as I required on my headphones, and I needed -1dB for Florence & The Machine, and -1dB for The Black Crowes (although I didn't test the last two on my headphones). -1dB doesn't seem significant on the face of it, but with that broad acting filter it certainly is.
EDIT 29/8/21: I found a more linear tone control recently. I found it over on miniDSP forums, someone had mathematically worked out the most linear (straight line) tone control represented by parametric filters. It's three High Shelf Filters acting together (you'd set the Gain to the same value to each one): 63Hz Q0.5 / 632Hz Q0.5 / 6324Hz Q0.5
As a lot of us know there's this thing called "Circle of Confusion" which I think could have been a phrase coined by Toole/Olive to describe the fact that target curves for the audio gear used in the production of any particular piece of music (in the studio) are not an industry standard between all of them.....so this means that some albums / tracks / songs can sometimes sound brighter or duller than they should really be when played back on your headphones or speakers (assuming your headphones and speakers are calibrated close to "neutral/flat"). Toole/Olive therefore say that Tone Controls should be used to tweak to user preference on different music productions for those very reasons. (here's a link to a presentation created by Sean Olive where he practically describes everything Harman re headphones, and there are sections on "Circle of Confusion" in there: https://www.listeninc.com/wp/media/Perception_and_-Measurement_of_Headphones_Sean_Olive.pdf)
So I've created a Tilt Tone Control for headphones & speakers, which is a simple EQ filter that can be implemented in any of your parametric EQ software of choice, this is the filter, it's as simple as this:
High Shelf Filter, 982Hz Q0.2
Here's a pic of it working in action on what happens to be an HE4XX headphone, but note the turquoise shaded area and my drawn in straight red line which is indicating the filter is pretty much acting linearly to tilt the whole frequency response from 100Hz to 20,000Hz:
I've tried out this "tone control" and I find it very effective. For instance, Red Hot Chili Pepper songs I find are generally recorded too bright, so my tone control filter fixes that with just -1 or -2dB on the Gain for that filter, you could probably even try it with just 0.5dB increments. You can easily notice 1dB changes in that filter because it tilts the whole frequency response from 100Hz upwards. High Shelf at 982Hz, Q 0.2 -> that's the filter I urge you to give it a try as a tone control. (that's naught point two for the Q filter, it's a very low Q filter!)
Give it a try if you're curious, and let us know if you find it effective or not. We can also talk about other tone controls you use, other software, plugins, etc.
EDIT: note that particularly with regards to use of this filter with headphones, it's not designed as a way of significantly increasing your bass level of your headphone, because often open-backed headphones roll off the bass early, so in terms of with use with headphones I recommend using my Tone Control Filter alongside a Harman EQ which will already include a Low Shelf Bass Boost filter which often counteracts the phenomenon of this early bass roll-off in open-backed headphones. Yes, so don't use my Tone Control Filter to increase your bass level, use a Low Shelf Filter bass boost or use it with an existing Harman EQ (eg from Oratory) which would already include that bass boost. My Tone Control Filter is used to change overall tonality, not for pumping up the bass specifically, sort the bass out in a different way.
EDIT#2: because my Tilt Control Filter affects so much of the frequency response, don't fall into the trap of the "Loudness Wars" when using positive Gain on my filter, because it will make it sound louder, and often louder sounds better - so instead try to get your mind to pay close attention to the tonality instead, and be aware it can increase the overall perceived loudness if boosted. Also note that you may need to apply a negative preamp alongside my Tone Control Filter if you use positive Gain on my filter - you'll need to do this to avoid digital clipping. However, if you're already using a headphone EQ (eg from Oratory), then you may not need to increase the Negative Preamp because often times the treble area is digitally reduced below 0dBFS in Harman EQ's. The point is.....Whatever EQ you do always check the Total EQ Curve to make sure nothing is creeping above 0dBFS.
EDIT#3: I will also add/emphasise that this Tone Control Filter is not for fixing your headphones, it's for fixing the "Circle of Confusion" in music production, this simple Tone Control Filter will not effectively fix anaemic bass nor piercing treble (or variations on that) in your headphones - fix your headphones first (probably with a Harman EQ) then use this Tone Control Filter as a means for subtley but widely tweaking overall tonality based on the variation ("Circle of Confusion") associated with music production, so this Tone Control Filter is nothing directly related to your headphones, but instead the music creation process itself, hence why you could also use this Tone Control Filter for speakers.
EDIT #4: I tried my Tone Control Filter on my speakers just now, and it works just as well for speakers as it does for headphones. Interestingly I needed the same -2dB Gain for Red Hot Chili Peppers music as I required on my headphones, and I needed -1dB for Florence & The Machine, and -1dB for The Black Crowes (although I didn't test the last two on my headphones). -1dB doesn't seem significant on the face of it, but with that broad acting filter it certainly is.
EDIT 29/8/21: I found a more linear tone control recently. I found it over on miniDSP forums, someone had mathematically worked out the most linear (straight line) tone control represented by parametric filters. It's three High Shelf Filters acting together (you'd set the Gain to the same value to each one): 63Hz Q0.5 / 632Hz Q0.5 / 6324Hz Q0.5
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