Creating fir filters for seas kingroy mk3

[Meander]

Hi everyone, I have some thoughts/questions about creating filters for my new speakers. I built the kingroy mk3 kit by seas and want to use the fir capability of the hypex amps. Right now I use the dsp preset 1 provided by Seas. I used the mmm technique to measure a sphere around my listening position and had rew generate filters based on that measurement. I used var smoothing to avoid overcorrection in higher frequencies. Im quite happy with the results above ca. 200hz the deviation from my target curve is less than +-2

Now about the FIR Filters, the Hypex dsp has 1500taps @93750hz on each output, OR 4500 on the Input. The plan is to use the hfd filters to make the speaker as flat as possible with measurements taken outside and then using the input eq to do some room correction with the available 9 biquads.

For the Crossover between Mid and Hi 1500taps are enough for steep 96db/oct Filters + Box Correction, but for the bass/mid crossover @ 215hz the taps are not sufficient, you have to go to at least 600hz with 48db/oct slope for the filter to be accurate down to the noise floor. I tried the high crossover but it didnt sound nice, crossover at 215hz sounds better to me.

4500 taps are enough for iir crossover lineariziation + box correction filters even on the bass @ 35hz

So its either iir crossovers + fir correction for a fully linear phase system (if you leave out the subsonic filter) with a delay of ca. 22ms
or
iir crossover for bass/mid and fir crossover + box correction for mid hi, so linear phase above ca. 250Hz and a delay of 8ms

Which configuration do you think would be preferable? My use case is listening to music, watching movies, djing, music production and mastering. For djing and music production with real instruments 10ms is the max delay i can tolerate.

 

[Sokel]

You should expect more overall latency, so if movies are a must too you must find a way with them.

 

[Meander]

You should expect more overall latency, so if movies are a must too you must find a way with them.

Rephase states the delay until the first impulse, which is half of the convolutionfilter. So is the "true delay" twice that number?

 

[Sokel]

Rephase states the delay until the first impulse, which is half of the convolutionfilter. So is the "true delay" twice that number?

You will really know after you be done with them.
Filters on their own measure differently than stack on to each other.

I would expect more than twice, even way more depending the scheme.

 

[Mister.Mole]

Depending on your usage scenario the 25ms might be completely fine.

If you listen to music only there should be no problem that it starts 25ms late. For movies you usually can delay the video accordingly in the TV or AVR.

For gaming or playing live music even the 8ms might be a problem.

You have 3 presets on the amp. Why not try all variants by yourself? Ideally double blind.

One more point. Phase "issues" caused by IIR tend to be more audible in the lower frequency regions and the steeper the filter. So the audible thing to correct is only possible with the 4500 taps overall and there might be no gain in adjusting the higher frequencies only.