3 ms·

they tune it so that you would not be able to distinguish a person talking behind you, from the recording of them being played with these speaker

they tune it so that you would not be able to distinguish a person talking behind you, from the recording of them being played with these speakers That's interesting! I'd love to know more about how your friend did it. It's trivial to get perfect on-axis sound (ie, the tweeters are pointed at your ears) even with cheap speaker components if you add some active DSP to compensate for the speaker's imperfections. In professional studio audio this is more or less the norm with monitors from Genelec, JBL, etc. In nearfield use (ie, you're close enough to the speaker that the direct sound from the speaker dwarfs the sound reflected off of the walls of the room) this will sound eerily good, basically like putting on a pair of headphones.

aljgz 4y ago
As @Jolter noticed, I'm unwilling to share information that can reveal the company the friend of my friend worked at. I'm also, not aware of much of the technical aspects of what they did, as my friend was a scientist and the other guy had done much of the hard work, so he did not know most of the details. Hopefully, in another visit there I can see him and find a way to meet the engineer, maybe I can encourage him to share his designs, tuning method, and other insights he has.
mrob 4y ago
>It's trivial to get perfect on-axis sound (ie, the tweeters are pointed at your ears) even with cheap speaker components if you add some active DSP Common digital room correction systems can improve the time-invariant linear components of an audio system's distortion (phase and frequency response) by convolving with an impulse response. The best results are obtained at a single point listening position, not a whole line. This technique cannot restore frequencies that were cancelled out by destructive interference, and may increase noise to unacceptable levels at frequencies where it has to apply gain. It supplements room treatment, not replaces it. It does nothing to improve non-linear distortion, e.g. harmonic and intermodulation distortion from soft clipping or asymmetries in the speaker motor, or time-dependent distortion, e.g. dynamic range compression from the coil overheating, or so-called "Doppler distortion" (better named phase modulation distortion[0]) from significant excursion of the cone. How much distortion matters depends on personal taste and listening material. Moderate harmonic distortion can be very difficult to hear in some sounds. And as the popularity of vinyl and tube amps show, some people prefer more distortion. [0] https://sound-au.com/doppler.htm https://sound-au.com/doppler.htm

aljgz 4y ago

As @Jolter noticed, I'm unwilling to share information that can reveal the company the friend of my friend worked at. I'm also, not aware of much of the technical aspects of what they did, as my friend was a scientist and the other guy had done much of the hard work, so he did not know most of the details. Hopefully, in another visit there I can see him and find a way to meet the engineer, maybe I can encourage him to share his designs, tuning method, and other insights he has.

mrob 4y ago

>It's trivial to get perfect on-axis sound (ie, the tweeters are pointed at your ears) even with cheap speaker components if you add some active DSP Common digital room correction systems can improve the time-invariant linear components of an audio system's distortion (phase and frequency response) by convolving with an impulse response. The best results are obtained at a single point listening position, not a whole line. This technique cannot restore frequencies that were cancelled out by destructive interference, and may increase noise to unacceptable levels at frequencies where it has to apply gain. It supplements room treatment, not replaces it. It does nothing to improve non-linear distortion, e.g. harmonic and intermodulation distortion from soft clipping or asymmetries in the speaker motor, or time-dependent distortion, e.g. dynamic range compression from the coil overheating, or so-called "Doppler distortion" (better named phase modulation distortion[0]) from significant excursion of the cone. How much distortion matters depends on personal taste and listening material. Moderate harmonic distortion can be very difficult to hear in some sounds. And as the popularity of vinyl and tube amps show, some people prefer more distortion. [0] https://sound-au.com/doppler.htm https://sound-au.com/doppler.htm