I think you know the answer already. Yes, it is strange to me too that this phenomena is not communicated well but still you can see the majority is following the "norm" correctly... (And by observing some phenomenon in commercial devices, my prediction is that engineers know what to do, it is just that these things are not communicated, especially in forums like this).
IME, whichever the driver that is inverted, it has been compromised. Bass is so important so normally you don't want to sacrifice the bass. But in a very good system (with good *dome* tweeter), often I feel that sacrificing the tweeter is unacceptable too. So I have NEVER made a 2-way with inverted drivers. But 3-way is a difficult case...
But remember that eventually we have to make trade-offs... Sacrificing what has to be sacrificed in a bigger whole system... Amplifier inversion is also part of the scheme. Or, inverting can sometimes be seen as opposed to compromise. Sometimes, it is better to "invert" the signal (locally or globally)...
That's a statement I've seen little research on, but it would be very interesting to do some absolute phase tests. If only I had friends who were blind and would let me put blind folds on them I could tell you for sure. So much research depends on double blind people I'm surprised they don't make more money.
There's a lot fewer blind people out there for these tests than you'd think. I tried to do a double-blind test and put an ad out in the paper for blind people. Not a single reply.
Erik
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I would highly encourage everyone to read this thread by Speaker Dave:
Crossover mods for the AR4x - Mods, Tweaks, and Upgrades to the Classics - The Classic Speaker Pages Discussion Forums
It is internet golddust. He clearly explains how phase overlap works. The OP might be interested in the 3rd post. "Best phasing in a system depends on a lot of variables including woofer depth, crossover order, crossover frequency, etc. you can't generalize and generally must use the phasing that gives the best addition."
Crossover mods for the AR4x - Mods, Tweaks, and Upgrades to the Classics - The Classic Speaker Pages Discussion Forums
It is internet golddust. He clearly explains how phase overlap works. The OP might be interested in the 3rd post. "Best phasing in a system depends on a lot of variables including woofer depth, crossover order, crossover frequency, etc. you can't generalize and generally must use the phasing that gives the best addition."
It's easy to test. Switch polarity on both L and R speakers and see if you can detect a difference.
Surely you jest about finding blind people. Double-blind testing means the subjects can't see the products being tested and the person conducting the test does not know the identity of the problem (to prevent him/her for subconsciously influencing the test). In this case, just not knowing what the polarity is or if it has even been changed should be enough. There will be no difference guys, think about it. I can't believe we are even debating this.
Of course I jest. 😀😀 I was making fun of people who can't see what's before them or anyone else unless it's in a double blind study. Whether absolute polarity makes a difference is something I have simply not tried to consider. It's best for me if I can't tell. It's less expensive that way. Otherwise I'm going to have to start worrying about time and phase coherent designs.
Best,
Erik
A resonance is dependent on the cycles and there are several. I have doubts as to the audibility of half, but an inter driver cancellation could be a problem.
If you are old (experienced), sometimes you don't need to do a test, because too many experiences will give you a conclusion of statistically high confidence.
There is a thread where PMA posted two files regarding absolute phase. I could do 12/12 of Foobar ABX with those files. In reality, the difference is IME always much greater than those two files. It depends on the music/recording (usually in bass performance), may be also on the speaker.
A member, Max, even mentioned that it affects the soundstage (I have never noticed because my critical listening in real life, including ABX have been always in mono).
I have a neighbor friend who seems to be more superior than I am in detecting phase reversal. He is around 55, making a living from selling used audio stuffs. Of course my ears are better than his, but often I'm amazed when I connect a cable (with no sign for plus/minus) to a speaker and upon a few seconds of listening to the speaker he commented "The cable was inverted...". This happens very often. I mean, how can he do that, even without comparing...
That's what I mean with experience. Once can be a coincidence, twice can be still a coincidence...
Hi Erik,
you did not get a response from double blind people in the paper because obviously they don't read it. 🙄
I have a question. If you are deaf in one ear should you rather listen to mono?
Actually no, you need two ears for direction, but one ear can tell dept.
Actually no, you need two ears for direction, but one ear can tell dept.
I'm not sure that's entirely true. A lot of work in Head Related Transfer Functions (HRTF) implies that with one ear you could tell more than just distance, but I don't claim mastery over the subject, just that I would not be surprised if it was possible.
Best,
Erik
Since the detection (i.e. halve-wave rectification) process in the ear is asymmetric, absolute polarity might probably matter more than some think.
The OP's question has already been answered correctly halfway through the thead in one of the shortest posts: Yes, by having the polarity of the woofer correct in a usual two-way speaker it is guaranteed that the absolute polarity of the largest part of the spectrum is correct. And also throughout the part where there lies the most energy in usual source material.
Regards
Charles
The OP's question has already been answered correctly halfway through the thead in one of the shortest posts: Yes, by having the polarity of the woofer correct in a usual two-way speaker it is guaranteed that the absolute polarity of the largest part of the spectrum is correct. And also throughout the part where there lies the most energy in usual source material.
Regards
Charles
Tomorrow I will do three test with my friends
Currently in this speakers the woofer is (W) wire + (D)driver + and tweeter is inverted W+ D-
Test 1 change the main wires amp to speaker polarity W+ S-
Test 2 invert woofer W+ D- tweeter W+ D+
Test 3 without change Woofer W+ D+ Tweeter W+ D-
I think that is difficult to ear the changes, In my last test with myself , I listened one week with the woofer inverted and don't remember any big different, now the XO is at 1.8khz, tomorrow the test will be with the piano playing in this frequency region and same orchestra with percussion will be very funny to see what happen.. I
Currently in this speakers the woofer is (W) wire + (D)driver + and tweeter is inverted W+ D-
Test 1 change the main wires amp to speaker polarity W+ S-
Test 2 invert woofer W+ D- tweeter W+ D+
Test 3 without change Woofer W+ D+ Tweeter W+ D-
I think that is difficult to ear the changes, In my last test with myself , I listened one week with the woofer inverted and don't remember any big different, now the XO is at 1.8khz, tomorrow the test will be with the piano playing in this frequency region and same orchestra with percussion will be very funny to see what happen.. I
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Consider the drummer himself.
On his side of the kit every drum hit starts with a rarefaction.
Furthermore in most cases when recorded, drums are close mic'd from the top and thus most drums we hear on recordings start similarly with a 'suck' rather than a 'push'.
(Kick and snare are frequently mic'd from both sides. The engineer will usually flip the phase on one of the mics. Which one he flips or if he flips at all is a matter of habit, his preference of what he hears at the moment or the tide in Abergavenny.)
FWIW last time I walked around a drum kit being played it did not sound remarkably (or unremarkably) different from behind (rarefaction first) or in front (compression first) of it.
Charles, I think the issue is not with the source, but with the loudspeaker mechanism. May be it is not a problem at all with planar/electrostatics...?
Jay, I disagree with the idea that a speaker should radiate like an instrument. If we were in an open space then any consistent source will get the sound to us. The difference is how much the room gets involved.
Preference about what? Inverted versus non-inverted of absolute phase?
In absolute term I prefer non-inverted, because the dynamic/sonic/drive/control is better. But there are minor cases where inverted can be good. For example, most midrange drivers are usually the weakest point of 3-way speakers. Often it is preferable to "calm down" the midrange, e.g. by running the midrange inverted (but I don't know if this could harm the soundstage or not).
Lately, I tried to find the best opamp-based preamp (I'm not an opamp guy, but I have plenty around, so this was more for fun). I used my ears to judge the results. Tried several opamps and find the best implementation for each. Tried several gain structures. Prior to that I started with finding the best power supply, including the components...
Between Wolffson DAC and TDA2030 amp, I tried 1/2/3/4 opamp stages in series with a potentio-based volume control. To my surprise, 4 opamps was better than 1 opamp (or 2 or 3). And I couldn't make a globally non-inverted scheme to sound better...(yet). But I didn't try to invert the speaker cable tho...
What I mean is... I thought the audibility of absolute phase is because of imperfection in driver mechanism. The driver (and complete loudspeaker) is not symmetrical. The sound of the cone moving forward is not the same with it's sound moving backward...
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