The 8PE21 gets my full approval in a few ways. It's a versatile driver, good for mainly midbass FLH applications (its strength IMO) and direct radiator use. The brutally low Qts makes it great for using all of its lower midrange output into the resonance area without worry of Fs negatively impacting its sound.
@profiguy
Yes, have seen this driver is very good in front loaded horns, but haven't tried that. My recollection is that it was good up to about 800Hz in FLH. Have you heard it excel into higher frequencies, say into 1.2-1.5kHz? In what kind of horn?
Time ago I looked into Inlows Sound 135Hz horns using this driver, but my readings left me with the impression it wouldn't play high enough.
Yes, have seen this driver is very good in front loaded horns, but haven't tried that. My recollection is that it was good up to about 800Hz in FLH. Have you heard it excel into higher frequencies, say into 1.2-1.5kHz? In what kind of horn?
Time ago I looked into Inlows Sound 135Hz horns using this driver, but my readings left me with the impression it wouldn't play high enough.
800hz is a realistic cutoff for the 8PE21 in a FLH, but you will need to leave a few 100 hz for xover overlap. The Inlow design is pretty good, but it needs to be long so the required small throat area can transition into the flare properly. I prefer the 12PE32 or 12MH32 in a midbass horn. Both drivers will work well up to 500 - 600 hz in a similar tractrix flare.
Quite a dream I had tha, a 12" midbass front horned then a sota standalone horn since 600. and the bass according all of that in the low end...
Should have a scary dynamic and close to ideal... I am sure I am not alone to dream it...
Too much huge and not a tube user on amps, so I come back towards classic living room loudspeakers goal.
I always thougth, whatever the others are saying than the Beyma TPL of Lewenski should not used below 1600/1800 for better coherence... while all is certainly in the crossover skills to make it different I assume.
Should have a scary dynamic and close to ideal... I am sure I am not alone to dream it...
Too much huge and not a tube user on amps, so I come back towards classic living room loudspeakers goal.
I always thougth, whatever the others are saying than the Beyma TPL of Lewenski should not used below 1600/1800 for better coherence... while all is certainly in the crossover skills to make it different I assume.
You have all hardcone drivers.
For those i would use accuton c168 - 990 to midrange.(amazing expensive) There are not much hardcone midranges. For cheap hardcone visaton AL130M would work.
And semihard cones, audax pr170z0 and satori texttreme comes to my mind. (Satori is not really midrange, but has quite good sensivity). And also morel tscm634.
Yes, this is why I dropped the idea of a FLH with 8PE21: I need it to xo at 1.1-1.2kHz. But every now and then I go down the rabbit hole again, like now 🙂 Comments about the driver being so good in a FLH keep drawing me back in. I guess one day I'll give it a try. And another with Faital M5N12 I have around.
Thats another good one. Also, the audax HM210Z0 is nice in a FLH for higher cutoff. I've seen that one go out past 1.3k in some special instances. The 8PE21 can be pushed to 1k, but you have to be slick with the xover. The required slope will be steep ie min 4th order if the horn has a phase plug and other features to help push it. The main issue with pushing a driver in a FLH hard is the cone integrity if the compression ratio is higher, but typically just increases THD. Efficiency isn't really all that important for hifi use anyways.
There are some surprising exceptions to which smaller cone mids work at cutoffs higher than theoretically possible. I like the Eminence Beta 6A in a FLH but also as a direct radiator. The NE123 was also pretty good in a quick mock up in a FLH, which its specs don't suggest.
Another nice little driver was the 4" pioneer used in the old Auratone FR monitors. As a midrange, it sounded very good. Needed a notch to sound its best though on a small baffle.
There are some surprising exceptions to which smaller cone mids work at cutoffs higher than theoretically possible. I like the Eminence Beta 6A in a FLH but also as a direct radiator. The NE123 was also pretty good in a quick mock up in a FLH, which its specs don't suggest.
Another nice little driver was the 4" pioneer used in the old Auratone FR monitors. As a midrange, it sounded very good. Needed a notch to sound its best though on a small baffle.