DLAY 1.2.0 lets its global high-pass and low-pass filters switch independently between 12, 24, 36, and 48 dB per octave. Those numbers do not move the cutoff frequency. They change how quickly frequencies are reduced once the signal moves beyond it.
That makes slope a separate decision from where you place the filter. A high-pass at 200 Hz can leave a broad transition into the low mids at 12 dB/oct, or remove the lower range much more aggressively at 48 dB/oct.
There is another detail worth keeping straight. DLAY already has per-tap filtering in its editor, but the new slope choices belong to the global HP and LP response curve, which shapes the wet output rather than assigning a different 12-to-48 dB slope to every individual tap.
A 12 dB/oct slope therefore describes a response that falls by about another 12 dB for each octave traveled into the stopband. A 24 dB/oct setting falls roughly twice as fast, while 36 and 48 dB/oct become progressively more severe.
The word “about” matters. Filter slopes describe the long-run rate of attenuation, not a promise that the signal will be exactly 12, 24, 36, or 48 dB down at one specific point beside the cutoff.
The exact curve around the cutoff depends on the filter design. Resonance, topology, and implementation can change the shape near that boundary, so reading 48 dB/oct as “48 dB quieter exactly one octave away” can be too literal for real audio filters.
In conventional filter terminology, each order contributes about 6 dB per octave of asymptotic slope. That makes 12, 24, 36, and 48 dB/oct broadly equivalent to second-, fourth-, sixth-, and eighth-order responses, although the slope number alone does not reveal every detail of the filter design.
That gives you uneven high and low rolloff shapes instead of one generic band-limiting character. A 12 dB/oct high-pass can gradually reduce low-frequency weight while a 48 dB/oct low-pass clamps the top end tightly, leaving the middle of the delayed signal comparatively untouched.
The reverse can be useful too. A steep high-pass can keep kick and bass energy out of a busy delay return, while a gentler low-pass lets upper harmonics fade over a wider frequency range rather than disappearing abruptly above the cutoff.
This matters more on delay than on a static one-shot sound because the wet signal may stay audible for several repeats. A broad transition can leave enough low or high energy to accumulate perceptually across the tail, while a steep boundary contains that range much earlier.
Cutoff frequency still does most of the positional work. Slope decides how much neighboring material survives around that point, so changing from 12 to 48 dB/oct without moving the cutoff can alter the apparent brightness, thinness, and separation of the same delay patch.
A steep slope is better when the unwanted range needs firmer containment. If a delay return is pushing too much sub energy into a dense mix, increasing the high-pass slope can remove more of that range without forcing the cutoff farther upward into frequencies you still want.
The same trade-off applies at the top end. Raising a low-pass cutoff to preserve presence and then using a steeper slope can keep that presence while reducing frequencies farther above it more decisively.
Steepness is not automatically an upgrade. A 48 dB/oct setting gives you stronger separation, but it also changes a narrower spectral boundary more abruptly than 12 dB/oct, which can sound less natural when the goal is gradual tonal decay rather than strict band limiting.
That is why comparing slopes at the same cutoff is more informative than moving both controls at once. Keep the cutoff fixed, switch the slope, and listen to what survives around the edge before deciding whether the problem is filter position or filter steepness.
If only the low end is masking the dry signal, a steep high-pass and gentle low-pass can solve that without darkening the repeats. Making both edges steep by default can narrow the wet spectrum more than needed, especially when the high-frequency content was never the problem.
That makes slope a separate decision from where you place the filter. A high-pass at 200 Hz can leave a broad transition into the low mids at 12 dB/oct, or remove the lower range much more aggressively at 48 dB/oct.
There is another detail worth keeping straight. DLAY already has per-tap filtering in its editor, but the new slope choices belong to the global HP and LP response curve, which shapes the wet output rather than assigning a different 12-to-48 dB slope to every individual tap.
A dB-per-octave slope controls the rate of attenuation
An octave is a doubling or halving of frequency. For a high-pass filter, moving from 200 Hz down to 100 Hz is one octave farther into the rejected range, while a low-pass filter works in the opposite direction as frequency rises.A 12 dB/oct slope therefore describes a response that falls by about another 12 dB for each octave traveled into the stopband. A 24 dB/oct setting falls roughly twice as fast, while 36 and 48 dB/oct become progressively more severe.
The word “about” matters. Filter slopes describe the long-run rate of attenuation, not a promise that the signal will be exactly 12, 24, 36, or 48 dB down at one specific point beside the cutoff.
The exact curve around the cutoff depends on the filter design. Resonance, topology, and implementation can change the shape near that boundary, so reading 48 dB/oct as “48 dB quieter exactly one octave away” can be too literal for real audio filters.
In conventional filter terminology, each order contributes about 6 dB per octave of asymptotic slope. That makes 12, 24, 36, and 48 dB/oct broadly equivalent to second-, fourth-, sixth-, and eighth-order responses, although the slope number alone does not reveal every detail of the filter design.
Independent slopes make the wet signal easier to bracket
The useful part of DLAY's independently selectable filter slopes is that the high-pass and low-pass sides do not have to use the same steepness. You can choose a gentle lower boundary and a much harder upper boundary, or reverse that relationship.That gives you uneven high and low rolloff shapes instead of one generic band-limiting character. A 12 dB/oct high-pass can gradually reduce low-frequency weight while a 48 dB/oct low-pass clamps the top end tightly, leaving the middle of the delayed signal comparatively untouched.
The reverse can be useful too. A steep high-pass can keep kick and bass energy out of a busy delay return, while a gentler low-pass lets upper harmonics fade over a wider frequency range rather than disappearing abruptly above the cutoff.
This matters more on delay than on a static one-shot sound because the wet signal may stay audible for several repeats. A broad transition can leave enough low or high energy to accumulate perceptually across the tail, while a steep boundary contains that range much earlier.
Cutoff frequency still does most of the positional work. Slope decides how much neighboring material survives around that point, so changing from 12 to 48 dB/oct without moving the cutoff can alter the apparent brightness, thinness, and separation of the same delay patch.
Steeper filters solve different problems than gentle ones
A gentle slope is useful when the filter should reshape tone without making the boundary obvious. It removes less nearby material, which can preserve more body around a high-pass cutoff or more air around a low-pass cutoff.A steep slope is better when the unwanted range needs firmer containment. If a delay return is pushing too much sub energy into a dense mix, increasing the high-pass slope can remove more of that range without forcing the cutoff farther upward into frequencies you still want.
The same trade-off applies at the top end. Raising a low-pass cutoff to preserve presence and then using a steeper slope can keep that presence while reducing frequencies farther above it more decisively.
Steepness is not automatically an upgrade. A 48 dB/oct setting gives you stronger separation, but it also changes a narrower spectral boundary more abruptly than 12 dB/oct, which can sound less natural when the goal is gradual tonal decay rather than strict band limiting.
That is why comparing slopes at the same cutoff is more informative than moving both controls at once. Keep the cutoff fixed, switch the slope, and listen to what survives around the edge before deciding whether the problem is filter position or filter steepness.
If only the low end is masking the dry signal, a steep high-pass and gentle low-pass can solve that without darkening the repeats. Making both edges steep by default can narrow the wet spectrum more than needed, especially when the high-frequency content was never the problem.
