If It Ain't Broke, Don't Fix It

The phase concern keeps coming up, but it's still an assertion rather than a demonstrated finding. Dave spent 1.5 years optimizing the Sierra-2EX with a Klippel NFS — if there's a genuine phase problem, the evidence for it needs to come from somewhere more reliable than measurements Danny made with a system that lacks the resolution to detect the fine detail this speaker was optimized around.

The "both sides, different ideologies" framing is more sophisticated than earlier versions of this argument, but it still sidesteps the key asymmetry. This isn't a case of two equally valid design philosophies producing different tradeoffs. Danny's v1 mod produced 6% tweeter distortion in the frequency range where our hearing is most sensitive — a finding Dave predicted in advance and documented exactly why he had avoided it. That's not a design ideology difference. That's a measurable, documented harm.

"Old-school Clio" is a generous framing for a system that demonstrably lacks the resolution needed for the precision work Danny claimed to be doing. The issue isn't that it's old — it's that gated measurements smoothed to 1/3 octave can't see what the Klippel NFS sees, and Danny was making claims that required seeing it. Calling it old-school doesn't change that mismatch.

If Danny's v2 is genuinely a great compromise, that case still needs to be made with evidence — measurements of sufficient resolution, or a controlled listening comparison. Neither has appeared.

I dont know the SR dude who improve speakers.

Here his answer to Amir ....

https://www.youtube.com/watch?v=3fWD6VcWJjc&t=876s

I discussed with Amir in the past and he demonstrated his ignorance of acoustics ...

It is well explained by Prof Milind Kunchur ...

it is one page to read at the end of this adress page and called "pseudoscience" in audio...

Try to contradict Kunchur  description of Amir... 

Also there is an interesting long article about hearing and sound by Kunchur... Read it before answering to understand why Amir sell a site (marketing) not science ...

https://sites.google.com/view/kunchur/audio-acoustics

The phase issue was documented with Amir's own measurement of the stock crossover where the woofer output is out of phase with the tweeter output, thus interfering with the response. Look at how the tweeter only graph line raises above the full speaker frequency response line. That alone is an issue that makes things sound fuzzy, blurry, congested, however you want to call it. Skirt the issue all you want, but that's a proper concern in design.

Try setting your subs even just 90° out of phase and see how uncomfortable it sounds. Then try rolling it even further to where it actually pulls down your frequency response and creates a dip. That would just be at bass frequencies. These speakers do that from 4khz all the way up to 10kh thus making all the treble sound cringy, dull and sharp at the same time. Even better to try, if your speakers have easy push on connectors to the drivers, try setting your tweeter wiring backwards just for fun.

Also the Klippel measurement documentation for the speaker would only cost the customer an extra $500...... That's kinda funny.

I apologize,  I misspoke. The measurements pointing out the phase interaction where the tweeter and woofer were measured independently was done by Danny. Amir did not measure drivers individually. Since they were on his video and he was questioning what was even wrong with the measurements to warrant an upgrade, I assumed they were his measurements.