A12p is a nominal 6.5” driver, and called such by the manufacturer and anyone in the know, some sellers will mistakening call it an 8” due to the big bezel. It should be noted that the actual active cone size is in the name, an A12x having ~12 cm D cone, A7x a 7cm cone etc.
Actual cone size is distinct from the effective cone size, as used in T/S measurement for instance, which needs to include half the surround.
The convention is to label drivers with their nominal size, everyone knowing that because of the basket & surround the actual cone size will be smaller. If you talk about the actual diaphram size you need to expicitely state it each time.
It should also be noted that talking just about cone size is also misleading since to be truly accurate one really needs to really talk about volume displacement as far as LF go, and one needs to know about effective cone size as one gets into the HF. In an idealized FR the cone "breaks-up” in such a way that the effective conde diameter is cleanly decreasing as the frequencies increase. This keeps dispersion from becoming laser-like at HF. A measure of how well this is done can be seen somewhat in the FR, large peaks means it is not all that well behaved. A physical characteristic of a cone that nicely decreases in “size” as frequencies increase is that they have a very curved cone, or a number of ridges, where the cone size decreases in steps. The other way of doing this is to have a whizzer, or as in some vintage drivers, a 2nd compliant surround “midCone” which effectively gives you a 2-way with a mechanical surround.
All that said, you are looking for an 8” which will give more sensitivivity and maybe more bass than a smaller cone, but optimum cone size as far as frequency fidelity is 4-5”. Id you truly want full-range, one needs to go with a fAST, where big woofers can do the heavy lifting and a FR is free to cover the mids & top with maximum fidelity. This does mean the introduction of an “evil” XO, but with a well designed system the ability to get away with a 1st order passive high level XO and less than a ¼ wavelength centre-to-centre driver separation at the XO most of the evil goes away and you are only left with the extra complexity.
</rant>
dave
It and power handling having no standard definition meaning that it is really hard to try to compare them.
dave
The Alpair is often described as an 8" driver. MarkAudio doesn't appear to describe the nominal diameter at all. Madisound calls it an 8". Confusion abounds.
A system's fidelity can only be analyzed within an SPL context. If a driver can't reproduce a signal at the required SPL, then it lacks fidelity.
Speaker design, as with all design, is about choosing one's tradeoffs. 4 - 5" cones have advantages and disadvantages. So do 3" domes and 8" cones.
A higher SPL requirement might require a different solution than a prescription that works at lower SPL.
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Yes, the art of loudspeaker design is choosing the set of compromises that best suit the end user, in diy usuallu yourself.
If high volumes, or low power amps, then a bigger speaker can justify itself, or if just loud a good FAST is hard to beat.
dave
PS: i have oft complained to Madisound about their mislabeling of the sizes. As well i am often on Skype with Mark Fenlon and he describes the speakers as the same sizes as i do.
If high volumes, or low power amps, then a bigger speaker can justify itself, or if just loud a good FAST is hard to beat.
dave
PS: i have oft complained to Madisound about their mislabeling of the sizes. As well i am often on Skype with Mark Fenlon and he describes the speakers as the same sizes as i do.
The Jordans are very much in the school of heavily curved cones that attempt to decouple into smaller cones as the frequencies go up. My 1st Jordans were Jordan/Watts modules in the mid 70s bought from Wilmslow. A wonderful speaker but bery coloured. My latest Jordans were JX92s (multiple prs) which had HF issues which made them unlistenable to me. The Mark Audio which i am a fan of are very much an evolution of Ted’s speakers, Mark being Ted’s apprentice for at least 5 years. The 1st gen Alpairs were very much in the Jordan mold, with some of the same issues as the JX92. The 2nd & 3rd generations are decided improvements. I’d really like to hear a set of Eikona, but they are going to have to be pretty good to make the 2x price penalty vrs the Alpair 10.3 worthwhile. I’m biased, but going in with the Eikona unheard i’d probably be willing to put my money on the A10.3, and certainly on the A10.3eN to be outright winners.
dave
I'm referring to the contraflex technology. They're not that expensive and they are available on your side of the pond. I'm sure you could afford a couple if you were really interested 😉😀
IIRC £180/pr (+ shipping from UK) vrs $185 USD per pair (admittedly on sale at Madisound) or $340/pr for A10.3eN. I have little discretionary budget as the moment. And still a bit of a bad taste from the JX92 pairs and the hit to the wallet they caused.
Contraflex is a marketing term for decreasing controlled breakup.
dave
Contraflex is a marketing term for decreasing controlled breakup.
dave
Probably Colin can set us straight on what contraflex is but I understood from the article that it's to reduce beaming
Exactly. If the effective cone radiating area gets smaller as you go up in frequency you get less beaming.
dave
dave
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