- Joined
- Jan 15, 2020
- Messages
- 6,904
- Likes
- 16,937
I like serious engineering which can be found from quite few brands, currently I mainly use KEF coaxials at my two home setups as I listen at relatively small distances and spaces.
-
WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!
Time aligned speakers - do they make sense?
- Thread starter Dogen
- Start date
Please let me emphasize again here that we (each of us) need to establish fully validated reliable reproducible "air-sound time alignment (relative delay in air sound)" measurement (and of course tuning) method(s) among all the SP drivers and L-to-R in sub-msec accuracy/precision at our listening position in our actual home listening environment; such method(s) should be fully "independent" from the measurement pulse/signal stimulation system/software and hopefully using independent second PC plus measurement microphone or similar independent measurement setup/gear(s) with measurement microphone.
I wonder how many of our ASR friends here on this thread have established and actually applied such "fully validated independent measurement methods of sub-msec precision".
Even very advanced XO/EQ/delay/measurement software would not be always "accurate/reliable enough" in assessing/tuning "time alignment of air sound"; one example case can be found here on my project thread; the story in that post strongly suggests that we do need "validated independent" measurement system.
The summary of my rather naive/primitive but reliable approach/methods in this perspective can be found here in my DSP-based multichannel multi-driver multi-amplifier stereo setup.
And, just for your reference, you can find my latest time-aligned system setup here and here on my project thread.
I wonder how many of our ASR friends here on this thread have established and actually applied such "fully validated independent measurement methods of sub-msec precision".
Even very advanced XO/EQ/delay/measurement software would not be always "accurate/reliable enough" in assessing/tuning "time alignment of air sound"; one example case can be found here on my project thread; the story in that post strongly suggests that we do need "validated independent" measurement system.
The summary of my rather naive/primitive but reliable approach/methods in this perspective can be found here in my DSP-based multichannel multi-driver multi-amplifier stereo setup.
And, just for your reference, you can find my latest time-aligned system setup here and here on my project thread.
Last edited:
Hey, that really made me want to assist you with the acoustics! I know you have added treatment, but it may not have been what's truly achievable.
Can time alignment be accomplished in the crossover, such as using all pass filters to adjust phase angles of the signals reaching the speedier drivers?
ernestcarl
Major Contributor
Not sure this is relevant, but this video discussion with examples could be of interest to others:
I could no doubt use your help !
I guess part of my jadedness towards rooms, is that 20 odd years ago I built an extension off of our home that was designed from the ground up as a sound room, with acoustical planning.
Big 350 cubic meter, wonderful sounding room, in a quiet rural environment. Very smooth RT60 around 0.2-3, live-end dead-end, early reflections absorbed or scattered...etc.
Countless hours optimizing multiple subs,
Thought i was in heaven, until i set some quality prosound gear up outdoors....wow, never-before-heard speaker clarity (and coming from an electrostat fan)
Anyway, since then I've used outdoors and mono, as the gold standard.
Although that may finally be crumbling.
Been playing with a LCR setup inside using three identical speaker stacks, and various matrixing techniques like Gerzon and others developed.
The center speaker provides the clarity that I most often find missing in indoor stereo. Clarity and envelopment !
It just might be time to get back into room acoustics..
- Joined
- May 1, 2021
- Messages
- 427
- Likes
- 1,309
The physical alignment is not necessarily enough since there is additional phase differences from the drivers and crossovers.
Yup, you can need some assistance when you think RT60 is valid for a small roomI could no doubt use your help !
I guess part of my jadedness towards rooms, is that 20 odd years ago I built an extension off of our home that was designed from the ground up as a sound room, with acoustical planning.
Big 350 cubic meter, wonderful sounding room, in a quiet rural environment. Very smooth RT60 around 0.2-3, live-end dead-end, early reflections absorbed or scattered...etc.
Countless hours optimizing multiple subs,
Thought i was in heaven, until i set some quality prosound gear up outdoors....wow, never-before-heard speaker clarity (and coming from an electrostat fan)
Anyway, since then I've used outdoors and mono, as the gold standard.
Although that may finally be crumbling.
Been playing with a LCR setup inside using three identical speaker stacks, and various matrixing techniques like Gerzon and others developed.
The center speaker provides the clarity that I most often find missing in indoor stereo. Clarity and envelopment !
It just might be time to get back into room acoustics..
Lyd & Akustikk | Små rom og etterklangstid
www.lydogakustikk.no
you call 350 cubic meters a small room?Yup, you can need some assistance when you think RT60 is valid for a small room
Lyd & Akustikk | Små rom og etterklangstid
I can't really buy into the room sizes the article you gave quotes....simply because i heard how nicely the room changed as i smoother out RT60 as low in freq as possible.
+1
Same here, 65m3 room and a change in RT60 is clearly audible (and measurable)
ernestcarl
Major Contributor
Yup, you can need some assistance when you think RT60 is valid for a small room
Lyd & Akustikk | Små rom og etterklangstid
In the context of "small rooms", I've heard another acoustician call RTx measurment graphs as "reflection-time-decay" curves. Obviously the original model is not valid for small rooms, but neither are these values completely "meaningless".
Sorry but that is not logical reasoning. The hearing decline one have is how one listen to sound (music, everyday sound) every day. To compensate for that decline will sound unnatural because it will not sound like the sound you hear every day (and that is your reference).
^I beg your pardon
^^Like a good 'passive' design with 'coherence' in both time/phase domains?^
^So! If I hear you correctly: A 'decent acoustic design' in a passive speaker with low-order filtering
does not make good sense.^I think that was the original question about time alignment?
Maybe, your point would be related to our personal preferences which may vary individual to individual.
I still would like to clearly hear the "sharp triangle sound" in 4th movement of Brahms Symphony number 4, and also would like hear the extremely high energy high Fq clear sound of Bimmel Bolle Antique Orgel (ref. here and here with video clip).
I periodically check my hearing ability by using nice headphone and audiometer software, and I know my ability is still much better than the average of my age group. I set a little bit of upward slope in around 8 kHz to 20 kHz (ref. here), however, just for my better listening sensation (maybe simulating my memorized sensation of 20 years ago
).That is it, and I essentially do not care any negative theoretical discussion at least on my "slightly upward Fq response curve in 8 kHz to 20 kHz".
Last edited:
Maybe, your point would be related to our personal preferences which may vary individual to individual.
No it is not a personal preference.
If you listen to live music (and everyday sound) with a X decline of your hearing, than that is how you perceive the music.
Listen to the same music on a system that try to restore the hearing problem will not sound right, because your reference, the live music, are with that decline.
I understand what you are insisting, but especially during and after the pandemic, I seldom attend to live music concert...
And myself and my wife, as well as our friends (many of them are professional or semi-professional classical or jazz musicians) are really happy with my audio setup having flexible on-the-fly relative gain (tone) tuning capabilities; we all know well that listening to live concert and listening to audio system are completely different world, and the preferable relative gain may vary depending on personal preferences and/or genre of the music.
I assume your point would lead us to a kind of endless spiral of discussions (just we already had the same in this ASR Forum so many times), and hence I would like to endup "this" discussion with you here on this thread.
Last edited:
Like usual, Rod has some interesting things to say on the subject:
sound-au.com
Full disclosure: I time align with DSP digital delay. Despite the digital glare, I think it's worth pursuing.
Phase, Time and Distortion in Loudspeakers
Full disclosure: I time align with DSP digital delay. Despite the digital glare, I think it's worth pursuing.
Multicore
Major Contributor
- Joined
- Dec 6, 2021
- Messages
- 1,789
- Likes
- 1,964
Is this the same question as asking about the conditions under which phase coherece matters, in some psychoacustical manner of speaking about what matters and what doesn't? This question must have been carefully studied and documented in the context of multi-microphone recordings many decades ago. But I admit that I just don't understand the subject.
For example, you can record a piano with two mics if they are far enough distant from each other but what about a church organ that's playing very, very slow music. Take two mics practically coincident and add 100 ms delay to one of them and then vary that delay gradually by a quarter of the period of the note being played.
I record my own acoustic guitars using a magnetic pickup and an air mic about 0.5 m away in a reverberant room. Aligning phase of those two tracks didn't make a difference that I could tell. (But I'm a cloth-eared music lover, not a golden-eared audiophile/recording engineer).
Someone here told me the Yamaha NS10 dominance in mixing all those years was all about its superior phase coherence and everyone knew it was a pretty crummy sounding box.
For example, you can record a piano with two mics if they are far enough distant from each other but what about a church organ that's playing very, very slow music. Take two mics practically coincident and add 100 ms delay to one of them and then vary that delay gradually by a quarter of the period of the note being played.
I record my own acoustic guitars using a magnetic pickup and an air mic about 0.5 m away in a reverberant room. Aligning phase of those two tracks didn't make a difference that I could tell. (But I'm a cloth-eared music lover, not a golden-eared audiophile/recording engineer).
Someone here told me the Yamaha NS10 dominance in mixing all those years was all about its superior phase coherence and everyone knew it was a pretty crummy sounding box.
One problem you get into from a practical viewpoint of speaker design is that phase alignment can only work at the crossover point. Away from there, the phase is no longer correct, and you get response ripples. You can hear those. The only mathematically perfect way to correct for time of flight difference is time delay.
Similar threads
- Poll
