Hi John,
I often find that when measuring in highly reflective environment like inside the car cabin, it is difficult to align the impulse responses (IR) without eye-balling and manually aligning each one. It becomes very tedious if there are many measurements to align for the purposes of designing FIR filters with the currently available options (Time align, Align IR start and Cross corr align). It would be appreciated if you consider adding another option to align IRs based on a chosen impulse slope rise threshold of a certain percentage, say 10%, 20% or user adjustable.
Let me illustrate, below are screenshots where I try to align impulse response of sixteen measurements taken in the car with the microphone spaced 10 cm apart in a square horizontal plane. In the first 4 pictures, I have removed 13 measurements to illustrate the issue a bit more clearly.
Original IRs before alignment
IRs after using Align IR start option
IRs after using Cross corr align option
IRs after using Time align option
As shown above and below with all sixteen measurements enabled, using the Align IR start option seems to work well until I inspected the IRs more closely.
The rise slopes of the IRs are slightly missaligned using Align IR start option.
The option that appears to achieve what I needed was to individually align the IRs using their initial slope rise with the cursor placed at 10% and selecting the Set t=0 at cursor option. This produces the IR alignment shown below.
I tried to upload the .mdat file but it is too large, here is the link https://drive.google.com/file/d/1GJGmGtm7zl-0I38dUFjqMk9joItNNW4_/view?usp=sharing
I often find that when measuring in highly reflective environment like inside the car cabin, it is difficult to align the impulse responses (IR) without eye-balling and manually aligning each one. It becomes very tedious if there are many measurements to align for the purposes of designing FIR filters with the currently available options (Time align, Align IR start and Cross corr align). It would be appreciated if you consider adding another option to align IRs based on a chosen impulse slope rise threshold of a certain percentage, say 10%, 20% or user adjustable.
Let me illustrate, below are screenshots where I try to align impulse response of sixteen measurements taken in the car with the microphone spaced 10 cm apart in a square horizontal plane. In the first 4 pictures, I have removed 13 measurements to illustrate the issue a bit more clearly.
Original IRs before alignment
IRs after using Align IR start option
IRs after using Cross corr align option
IRs after using Time align option
As shown above and below with all sixteen measurements enabled, using the Align IR start option seems to work well until I inspected the IRs more closely.
The rise slopes of the IRs are slightly missaligned using Align IR start option.
The option that appears to achieve what I needed was to individually align the IRs using their initial slope rise with the cursor placed at 10% and selecting the Set t=0 at cursor option. This produces the IR alignment shown below.
I tried to upload the .mdat file but it is too large, here is the link https://drive.google.com/file/d/1GJGmGtm7zl-0I38dUFjqMk9joItNNW4_/view?usp=sharing
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