When I was working with dome mids, I was in the habit of aligning phase through a crossover but I wasn't using polar measurements as I do now. Therefore I'm inclined to consider breakup and power response. It's also possible that more of the highs illuminate the baffle, but I'd want to see measurements before making that claim.
Just a small remark: it would need ~1000 W for 113 dB. And the driver has a small 0.75" voice coil!
Here is an example of a 3" ATC in a speaker sounding very bad. The reason was a bad crossover and not a bad driver. There are similar examples if you search. It seems to be fairly common for inexperienced DIYers and/or kit builders to opt for extremely expensive drivers with cheap primitive crossovers (or defective ones in the example) and cheap primitive cabinets.
They market them as full range because they are full range drivers and not midrange drivers. As was mentioned by several people earlier in the thread full range drivers cannot play loud and cleanly enough to function as a midrange driver in a conventional 3 way (e.g. 2 x 8", 5" mid, 1" tweeter) plus their sensitivity is usually too low to work well with a passive crossover. Generally full range drivers need to be in arrays if they are to deliver clean high fidelity sound in the home. A filler driver could work but a filler driver is usually closer to a tweeter than a midrange driver.
For me, a real midrange driver would be something like this:
Hardly usable below 450 Hz, but then equipped with enormously high efficiency and thanks to the 1.5 inch voice coil also electically quite resilient. It could theoretically reach almost 115 dB/1m.
However, the impedance curve doesn't look so nice, so we'll have to see what acoustical effects that has.
Hardly usable below 450 Hz, but then equipped with enormously high efficiency and thanks to the 1.5 inch voice coil also electically quite resilient. It could theoretically reach almost 115 dB/1m.
However, the impedance curve doesn't look so nice, so we'll have to see what acoustical effects that has.
Resonances of that size will be audible. The task for those interested in high fidelity reproduction tends to be avoiding high efficiency resonating drivers and low efficiency drivers that cannot cleanly reproduce transients (e.g. fullrange or midwoofers) and look for drivers with inaudible resonances (e.g. stiff or well damped cones depending on design approach) with sufficient clean SPL (e.g. around 3-5" cone, 90+ dB efficiency and 100+ W power handling with some wriggle room). Assumes the woofer and tweeter are adequately sized to cleanly reproduce standard levels at 3-4 m in a room. If not (e.g. small desktop speaker or limited to less than standard SPLs) then other drivers may be suitable.
And that is what we have beautiful old relics like this for.
12" midrange driver, smooth resonance free output , low distortion and high efficiency.
11kg, limited xmax, high motor strength, coated damped surround, and a fairly stiff suspension.
This one is a bit too extreme' in terms of being designed exclusively for midrange. Hard to find a natural use for it really, not gonna deny that.
Or it's less refined 'siblings' like the JBL 2020H, although with a wider useable range and more advanced motor structure.
Pretty much the opposite of a 3" fullrange or 2-3" dome as long as were talking of direct radiators.
Different tools for different tasks.🙂
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This is about exactly what I saw when I was simulating using them. Especially for the smaller ones. For the 3" and smaller it would require using to to match a pair of woofers. Even then, they barely just cut it
Oops, forgot that the 3.5" Tymphany TC9FD-18-08's excursion wouldn't be it's limiting factor at 400 Hz.
Peaks of ~106dB would be more in the ballpark at 400Hz.
That said, horn loaded, the TC9FD-18-08 reached well over 120dBA slow/one meter, and had less IMD than the best 3" voice coil compression drivers I've tested.
Surprising how clean it sounded until a second before the voice coil failed 😉
Art
I'm late and this party is already 4 pages long, so please forgive me if I am redundant, but I may have answered your original question in this blog post. The answer AFAIK is distortion and dispersion. Sadly the former is very rarely available from manufacturers.