The AF Credentia 3 is really limited by the 30W power rating of the 5in (actually 4in) midrange.
I hope Harry decides to go with Purifi drivers for the next iteration - probably get another 3-4db of headroom before distortion is equal.
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I hope Harry decides to go with Purifi drivers for the next iteration - probably get another 3-4db of headroom before distortion is equal.
The power handling issue is only a problem until more people start developing coaxial drivers. I predict multiple players in the aftermarket space will have competitive products within 12mo.
Even with 30W, it's only covering a little from than two octaves from 430 Hz to 2000 Hz, it's perfectly fine.
The sine sweep at 96 dB is clean in the midrange, with music, that's probably upwards of 106 dB for the bass. The bass driver will give up before the midrange with most music.
Nice thing about good coax drivers, with the tweeter levelled with the midrange membrane, is that the tweeter forces a larger voice coil diameter for the midrange, which helps with power handling. If you are referring to the automotive aftermarket segment, I doubt that it will produce high quality coax speakers. They've had enough time to do so when aftermarket systems were actually a thing. Aftermarket car audio has become much smaller in the last 2 decades.
The Sica 5.5C1.5CP-8 seems to do pretty well here. I high-pass it at 500Hz and used as a mid it avoids the main drawbacks it seems.
https://www.audiosciencereview.com/...6-5-coaxial-speaker-build.61464/#post-2255210
A Purifi would be a dream but it seems they are not coax fans. There's always hope!
https://www.audiosciencereview.com/...with-a-ptt-tweeter.44523/page-25#post-2524848
kemmler3D
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What do you know that we don't? Coax is not a new technology but I have seen few designs come out that compete with KEF stuff over the years. What's special about 2026-27?
It's not power handling, it's SPL. Making it more sensitive for the same input power or able to handle higher input power does not improve that, other than the fact that higher sensitivity often requires greater driver area which reduces excursion requirements.
Just by virtue of being coaxial the tweeter's output is modulated by the midrange/woofer moving. Yes, this is moderated by the coax unit being used as a M/T instead of a MW/T, but it is still definitely present.
My hot take is that if peoples brains are tricked into thinking louder and better looking speakers sound better in sighted conditions, then for sighted listening louder and better looking speakers are better.
Another hot take: difference between good speakers and great speakers is pretty minor in most listening conditions
Another hot take: Liking fancy turntables and electronics is fine even if you know there are shortcomings. I'll take playing with accuphase or audio research toggle switches over state of the art but commodity amazon sourced future land fill component most times
Another hot take: difference between good speakers and great speakers is pretty minor in most listening conditions
Another hot take: Liking fancy turntables and electronics is fine even if you know there are shortcomings. I'll take playing with accuphase or audio research toggle switches over state of the art but commodity amazon sourced future land fill component most times
Of course modulation technically exists in coax speakers. But is it audible? I think we agree that some of the best speakers out there are coaxial designs.
What about a mid-woofer moving +/-5 to 10mm while playing midrange/lower treble? Wouldn't that be a much greater source of Doppler distortion?
And shouldn't we see IMD rising in coax designs if this is an issue?
My take is that BL nonlinearity is by far the major source for IMD. Maybe once this is solved (e.g. Purifi speakers if they perform as specified) Doppler starts to show. Wasn't there a tech-note from Purifi about Doppler?
Visual cues and imaginated sound advantages may wear off over time. That expensive interconnect you thought to improve clarity will soon require replacement with a more expensive cable. Good looks may last longer and provide a level of satisfaction on their own.
Generally true but it's the small details that count.
As long as sound quality is good, why not enjoy high-end gear. And even some shortcomings may be acceptable if one gets satisfaction from other factors. Turntables and tubes remind me of a campfire. I can understand the joy some get out of them. Personally, I don't care about these sentimental factors. Good sound is much more important to me.
thewas
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Exactly, also SOTA designs like for example the Genelec and KEF coaxes have first a fixed waveguide around the tweeter and after that the "ring" mid membrane comes.
Imo there are definitely two use cases where a coaxial offers significant advantages over a more conventional configuration: Listening at close distances (because they have zero vertical spacing between mid and tweet), and listening from a significant vertical off-axis angle (because they have no vertical off-axis dip in the crossover region).
But as the listening distance increases (and of course depending on the specifics) the vertical spacing between mid and tweet ceases to be of audible significance. And at normal vertical listening angles (fairly close to on-axis vertically) that nasty-looking vertical off-axis dip is of little or no consequence.
So, my response to the poll was "Depends".
I said something above that might have raised an eyebrow or two: "At normal vertical listening angles (fairly close to on-axis vertically) the vertical off-axis dip is of little or no consequence". At first glance that statement might seem outrageous because anyone can eyeball the data and clearly see a huge ugly dip in the vertical off-axis response. But we have to go past merely LOOKING at the measurements; we need to understand the WHY behind that huge ugly dip in order to correctly evaluate what its presence in the measurements does and does not imply. Let me elaborate:
The vertical off-axis dip of a conventional-configuration loudspeaker is a LOCAL INTERFERENCE effect, so it appears ONLY where the sound waves from the midrange and tweeter pass through one another along that angle. For non-coaxial drivers, in the crossover region where the midrange and tweeter are both playing, there will be an angle along which the midrange driver's output arrives about one-half wavelength later than the tweeter's output, putting them out-of-phase with one another. So a microphone along that angle would MEASURE a reduction in sound pressure (a dip) as the pressure wave of the one is partially cancelled by the rarefaction wave of the other. But those two sound waves - the one from the mid and the other from the tweeter - pass through one another and continue onward, unattenuated by their interaction! So we end up with dippage that looks absolutely dreadful to the eye in the measurements, but whose net effect is negligible outside of the direct sound along that specific angle.
So if your ears are at or near the correct height, and this comb-filter dip occurs along (and ONLY along) an angle which bypasses you entirely, and which occurs ONLY in the direct sound (and disappears entirely in the reflection field), then that dip has NO audible effect.
This is by no means a complete look at "coaxial vs non-coaxial". I can think of good arguments for both, such that in a situation where the listener is going to be far enough back and fairly close to on-axis vertically, the PERFORMANCE of a specific speaker MATTERS FAR MORE than which configuration the designer used to get that performance. But in specific use cases - close range listening and/or vertically well-off-axis listening - the coaxial configuration DOES have clear advantages.
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Fully agreed. In my anecdotal and subjective experience, provided that the vast majority of your listening is done while aligned with a speaker's vertical axis, limiting vertical dispersion can be advantageous. Most of what we consider "envelopment" happens along the horizontal plane.
thewas
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Looking at most non-coaxial loudspeakers in spinorama.org the ceiling or floor reflexions show this dip clearly, so above is rather an exception.
That's still a comb filter effect.
I may have over-stated in saying that it has "NO audible effect", but I think it only has a very minor audible effect at best, as the energy from both drivers is still present and continues onward. The cancellation dip occurs only along the angle(s) where the energy from the woofer and the tweeter are largely out-of-phase relative to one another.
To put it another way, if one or the other of the drivers had that much of a dip in its actual frequency response, that would be vastly more audible.
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thewas
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Usually this angle range is quite wide though (this can be also seen in the polar maps) and overlaps with the significant reflections from the ceiling and the floor.
Its audibility and importance is to be further investigated.
Below is the "estimated in-room response" curve of the Dutch & Dutch 8c; I posted this in the 15c thread as well. There may be a tiny bit of dippage in the region where those vertical off-axis dips occur, but it's not much.
In contrast the woofer's 1.5 dB bump @ 400 Hz kinda sticks out like a sore thumb. So, according to this curve, THAT arguably very minor bump is of much greater audible significance than those dreadful-looking off-axis dips in the vertical response.
thewas
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Yes, with the averaging through the EIR formula its impact is significantly reduced,
although in real life this depends also on the listening distance and the reflectivity of the various room surfaces and also the EIR alone doesn't say much about perceived fidelity as like Toole writes our ears and brain operate very differently than a microphone average. For example it would be theoretically possible to engineer a loudspeaker where the horizontal directivity deviation compensates the vertical directivity deviation and the EIR is thus still perfectly continuous, still such probably wouldn't sound as neutral as a loudspeaker where both are smooth.
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