what is the point of expensive coaxials with ragged response?

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Hi,
There is always 'latency' involved as long as you are using loudspeakers, it's usually named 'time of flight' and equal to the distance from loudspeakers to your ears, as it's already been told previously.

When djing i usually use a pair of nearfield monitors so something like 1m distance. When comparing to what i have in the cues ( headphones) no issue i can synchronize vinyls with monitors as references ( time of fly is so short you don't hear it).

When we had our sound system we usually used much more distance and way bigger loudspeakers as monitoring ( up to 3/4m distance and 15"+1,5" CD powered by 1kw amplifiers). In that case the latency was much more an issue and you could not open fader before checking in headphones with both track playing together if they were synchronised or not ( in bpm they would be in sync if you used monitor as reference but there would be a delay in beat of reference because of time of flight of sound)...

Most musician i worked with are insensitive to delay up to 5ms. I encountered 2 exception one of them being a guitar player which was bothered at 2,5ms latency ( on very fast bpm palm mute riff).

This led me to use 2 preset with my dsp: one with FIR ( which imply a larger than 5ms latency by nature) and a IIR one with lower than 2ms for 'real time' monitoring.

That said, when i chill on my synthesizers i often have 10 to 20ms latency because of some limitation of my synth setup and can still play things with them ( but i'm not a virtuoso at keyboard to say the least...).

In otherwords 5ms latency/delay is the limit for most peoples. You can tolerate more or less depends on individuals.
If you ever recorded through a Protools HD of 10 years ago you were experiencing something around 1 to 2ms latency by the system itself... i've never heard anyone complaining about this.

NC535 answer is spot on. The delay we use is to correct an issue and so can not be compared to 'time of flight' latency issue.
Here is an example of what it'll change:
https://www.audiosciencereview.com/forum/index.php?threads/tannoy-system-600-speaker-review.11919/

The dip at 1,5khz is because the woofer fire sound sooner than the tweeter and cannot be solved by eq. Only a delay on woofer can solve the issue ( or phase manipulation through allpass filter).

And i know because i actually own a system 800 passive pair plagued by same issue i solved studying the active version schematic which did not feature the dip... ;)

Coax have ragged high response. True for most. But we don't listen to a graph and other parameters are way more important to good sound than FR alone on one (single on-) axis...
 
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Do you and others have trouble telling the difference between a query and a claim?
No. It appears you're conflating reflex reaction time with the auditory impact of time delay. Two separate domains. In an uncorrected coax one driver is already defined as delayed relative to the other. 10 cm is a wild physical differential. A delay is in the range of 0.1 ms or less is more realistic. Delays between drivers likewise exist in the vast majority of non-coaxial speakers since the tweeter is normally physically closer than the woofer's acoustic centre.
Delaying the first arrival driver simply matches it to a preexisting and unavoidable delay from the late arrival driver, coax or not. As Guerilla notes this has an impact on frequency response in the crossover range. It is also foundational to initial impulse and step response. To what extent this deviation from ideal matters audibly is open to debate but what isn't is that it will be experienced as a perceptible delay, any more than is leaning back in your listening seat.
 
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Delays between drivers likewise exist in the vast majority of non-coaxial speakers since the tweeter is normally physically closer than the woofer's acoustic centre.
The ill effects are somewhat minimized using either first-order XO and aligning phase throughout (but for above-mentioned midwoofer physical distance extra latency), or higher-order XO to reduce frequency overlap and then aligning phase electrically at just the XO frequency. My own preference is to align first the acoustic centers (so no relative delay) then apply first-order XO and try to make sure phase is aligned as well. This of course isn't possible with a "bridge" coaxial (without DSP etc.).
 
Am I understanding correctly that this is regarding the spill from the xover slopes, and with staggered physical alignment there is a chance for holes and peaks?
Im really not strong in this but if you have two speakers instead of one it will be louder. If one is 180° out of phase with the other they will instead cancel eachother.
In case of coaxial the distance difference between woofer and tweeter will cancel only some frequencies, since they dont have the same frequency response and only one? frequency has a wawelengh to equal cc?-difference between the two driver parts.
That may be partly an explanation, but dont put money on it😊
Cheers!
 
Should I take note that the sound of from the woofer comes from the apex at the pole rather than the whole surface of the woofer cone including the leading edges and surround? Is this what makes the Pioneer's physical alignment incorrect over the correct ones in the high-end drivers and the Phoenix Gold?
So at the pole is the correct physical alignment? What about all the output from the cone, extending out from the apex? Isn't all that output ahead of the tweeter in the pole?
 
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Please don't tell me that the latency will not be noticeable, as that would mean that the alignment could have been left alone
For those that use DSP but not a simulator, who find the standard filters too basic to line up properly, delay has become a simple tool for small variable amounts of wholesale but necessary phase shifting.

This was not a problem before DSP.
 
I wonder how much reality there is to the idea that evolution leaves us with a preference towards full range. Full ranges generally sound a little unatural to me due to their limitations that I feel are worse than putting a xover in the mid range as is common.

I've got plenty of 2 ways and 3 ways, some coax, they all provide me with what I'd say is natural sounding voices and I don't feel they lacked in that regard to fullranges. I find the beaming of fullranges very distracting.
 
beaming of fullranges
This is another one that I can't get my head around. Keep in mind that 3.5" is the largest FR driver that I have tried and 6.5" is the largest coaxial in my experience

I have heard this mentioned re FR drivers. Is this related to the tweeter frequencies or lower? Is driving those frequencies from the larger cone a bad thing?

Right now, I am listening to 2.75" FR drivers. It seems very balanced if I moved around. From the meaning of the word beaming, I am guessing some sort of torch like effect. How large does the FR have to be for this to become apparent? Similarly, at what xover points would the beaming start being a problem with a larger 6.5" coaxial or two-way?
 
I have heard this mentioned re FR drivers. Is this related to the tweeter frequencies or lower? Is driving those frequencies from the larger cone a bad thing?

before I answer, tossing out my daily complaint about this forums qoute system.

The beaming occurs at higher frequencies. Tested a few drivers to see what fullrange and WAW is about. The beaming bothered me because if you moved even a little bit off axis you lose that upper mid and treble. Leads to a very narrow sweet spot. I guess someone could find a use for that sort of dispersion. tebm46 was one I tried recently and bleh, hf beaming.

I don't really like beaming with any driver covering any range, I even find many 1 inch domes narrown to an irritating degree, I can still hear high up and care about that region unlike most folks I run into on here ;p
 
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Have you found this to be true for FR drivers that have a Madonna bra dust cap? Maybe this feature works with dispersion? I can’t replicate the effect that you describe moving around about either side of one driver. This makes me think back to the topic, at the risk of discussing solutions too early, has this shape been tried as the cone for a coaxial tweeter? Could it bring alignment from acoustic tip to centre to back of the two integrated units that make up the coaxial?
 
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Randy, i suggest you to play a bit with the linked excel sheet to see at what frequency beaming occur for different size of drivers ( speaker directivity simulator 1.03):

https://www.tonestack.net/software/speaker-directivity-simulators.html

It's theorical and some things can change real life results a bit but it'll be close to what you'll see as outcome from the sheet. You'll then probably see why coax xover freq is dependent of the driver overall size. Keep in mind the 'tweeter' or CD eat a lot of space so it's wise to consider the woofer membrane area to be more or less equal to the smaller size of driver availlable (eg: a 15" coax have a woofer membrane close to a 12", a 12" coax to a 10", 10" coax to an 8", 8" coax to a 6,5", etc,etc,...). You'll quickly see the 90° beamwidth most of them claim is close to xover freq to tweeter...

I'm like Wafflesomd, i dislike beaming. I've got some FR loudspeakers though as i find them interesting for some quality they have but could not live long term with them only. Especially for work...

Never experienced a 'big' coax? You should. Very interesting experience imho. To tell the truth 15"DMT 2 are probably the loudspeaker i liked the most to this day. Too bad it's the same size as my mains ( and after 25 years living with 'big' ugly rectangular box i want something different now) and it's now rare to find a pair which have not been beaten up to death as they were mostly used in control rooms.
 
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@Randy Bassinga I dont know if one of my experiences explains a bit.
I have this speaker I showed you




IMG_20240210_102243.jpg

They are old and were praised as the best computer monitors you could get at that time when such were mostly crap. They cost 4-500 dollars with a lm38xx based amp included, which was Hi-End prizing then I got them for 70 dollars cause a court seized the OEMs whole stock for selling them as illegal "copies" They do sound awesome. They are not neutral, but colors all music a bit to sound better than what's recorded. I found out that their drivers were Tang Band W3-871SC. Got two of those and made holes right under my sidewindows in my car. I was very happy about the sound, but one day my friend with "golden ears" heard them and complained about the highs. I protested but the he just put his flat palm at the right angle directing top end to my ears. -Dramatic improvement!! The problem was that that with this placement we were listening off-axis. Could have made a flange to angle them I guess, but I've shown you in other thread my attempt of a solution for Sweet Sweet Stereo Music at the wheel 😄 Cheers!
 
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Randy, i suggest you to play a bit with the linked excel sheet to see at what frequency beaming occur for different size of drivers ( speaker directivity simulator 1.03):

https://www.tonestack.net/software/speaker-directivity-simulators.html

It's theorical and some things can change real life results a bit but it'll be close to what you'll see as outcome from the sheet. You'll then probably see why coax xover freq is dependent of the driver overall size. Keep in mind the 'tweeter' or CD eat a lot of space so it's wise to consider the woofer membrane area to be more or less equal to the smaller size of driver availlable (eg: a 15" coax have a woofer membrane close to a 12", a 12" coax to a 10", 10" coax to an 8", 8" coax to a 6,5", etc,etc,...). You'll quickly see the 90° beamwidth most of them claim is close to xover freq to tweeter...

I'm like Wafflesomd, i dislike beaming. I've got some FR loudspeakers though as i find them interesting for some quality they have but could not live long term with them only. Especially for work...

Never experienced a 'big' coax? You should. Very interesting experience imho. To tell the truth 15"DMT 2 are probably the loudspeaker i liked the most to this day. Too bad it's the same size as my mains ( and after 25 years living with 'big' ugly rectangular box i want something different now) and it's now rare to find a pair which have not been beaten up to death as they were mostly used in control rooms.
Krivium, thanks for the link and insight

How large are your FR speakers?

6.5" car coax would be the largest that I have tried. I wouldn't know where to audition big coax, I'll be in Brisbane on the weekend so if hi-fi shop there has one......

I wanted to get a Mazda rotary but same beaten up to death situation :D
@Randy Bassinga I dont know if one of my experiences explains a bit.
I have this speaker I showed you




View attachment 1272289
They are old and were praised as the best computer monitors you could get at that time when such were mostly crap. They cost 4-500 dollars with a lm38xx based amp included, which was Hi-End prizing then I got them for 70 dollars cause a court seized the OEMs whole stock for selling them as illegal "copies" They do sound awesome. They are not neutral, but colors all music a bit to sound better than what's recorded. I found out that their drivers were Tang Band W3-871SC. Got two of those and made holes right under my sidewindows in my car. I was very happy about the sound, but one day my friend with "golden ears" heard them and complained about the highs. I protested but the he just put his flat palm at the right angle directing top end to my ears. -Dramatic improvement!! The problem was that that with this placement we were listening off-axis. Could have made a flange to angle them I guess, but I've shown you in other thread my attempt of a solution for Sweet Sweet Stereo Music at the wheel 😄 Cheers!
That looks a lot like the unit in the Logitech THX systems like mine. Here is the thing, Logitech fits them from the back of the baffle and the baffle forms a shallow waveguide type unit around the driver

I just tried the palm and ear trick. It does make a lil difference in lifting the highs, but I do have very sticking out elephant ears. The stereo speakers are 1m apart and about 1.2m in front of my position
 
Phase plugs yes. They also stop reflections from one side of the membrane to the other. Those reflections cause peaks in frequency response sometimes quite nasty.
My brother's Dali 450 have the best bass I've ever heard. In the sense that I've heard them in 10+ different rooms and they always sound great.
They have however a little nastyness in the middrange.
They have two 6 inch Basses. One or both of them playing midd to meet the tweeter.
I have an extra set lended out, and I'd love to fit phase plugs on them to see if it fixes anything. In the process i'd like to test my InnerSurroundInvention😄 on one of the speakers. Using Logitech surrounds glued to centerpole under phase plugs and to the cone.
I dont know if it was already invented and found out to be useless 😊
Well. We only have the beard we sit on as we say in Denmark.
Cheers
 
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How large are your FR speakers?

They vary in size... if i count the one into the TV, Boombox in the kitchen and bathroom... it range from 2" to 4". The 4" is the one i listen to for 'serious' listening, an Alpair 7.

I've heard much bigger one up to 12" or 15" in PA. Fane products. Those are good drivers but not my preference as i'm sensible to beaming and they start to have this behavior lower in freq ( wrt smaller diameter), circa 1200hz for 12", 1k for 15".

6.5" car coax would be the largest that I have tried. I wouldn't know where to audition big coax, I'll be in Brisbane on the weekend so if hi-fi shop there has one......

I would not bet on hifi store if you want to audition bigger than 8" coax: bigger drivers seems to have gone out of fashion in hifi world, people seems to prefer slim looking rather than 'better' sound. And i can understand the trend even if i know it'll compromise outcome soundwise.

Your better chance to listen to some 15" or 12" would be in a PA rental shop: they are most often used in 'wedge' monitors, sometimes as satellite 'fills' to cover area the main FOH system have into shade area. But don't expect them to go low in freq, that's not the point with this drivers ( as they rely on FOH subs to cover the lower freq band). Efficiency and directivity management is the point with them: vs lower diameter drivers they have HUGE dynamic and (from the newer models) even directivity management.

Anyway, my experience with coax tells me they should not reproduce lower freq as intermodulation distortion happen when driven hard. At least this is true for all the 'Tannoy style' i used ( were woofer membrane is used as part of waveguide). It is probably different with 'Altec style' coax but i have not played with them.
Some Tannoy drivers were totally ok as 2ways but they compromised on other point. Anyway they are things of the past. Maybe Fyre will develop newer ones but i doubt given the trend for 'lifestyle' products... which let us with only PA products if you want 'large' diam coax. They are totally fine anyway if you like high efficiency and have a dsp...

The question remaining is at which freq to set the lower xover point ( to bass/sub)? I like circa 250hz some other members here prefered lower around 80hz.

Another thing: coax are not supposed to be listened on axis. Something in the range 10°/20° off axis is often the sweetspot for them so you'll have to experiment with toe-in/off. This is one of the differences with FR imho.

Your Pionneer coax approach are used in studio monitor world as Freedom666 pointed: Geithain monitors are very, very good. Not widely known because of historic iron curtain but it change, for the good. They have innovative approach for a long time now, and were really in advance as they promote cardioid behavior in low end with coax approach since... 80's. 45 years after it's the trend most brand tend to follow ( Genelec, Amphion,...).

Mazda RX are good cars. Fun to have same engine technology as plane from the 50's!
 
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