hi everyone
mids treble will again be PR170mo/Rt2ha
1st order xo, points around 300hz/1500hz
Woofer requirements: a honest 98db efficiency, smooth roll off, no 10db peak at 1.2khz please!
Box will be 150L
I like this, but discontinued
https://www.usspeaker.com/beyma 18PW1400fe-1.htm
many thx!
mids treble will again be PR170mo/Rt2ha
1st order xo, points around 300hz/1500hz
Woofer requirements: a honest 98db efficiency, smooth roll off, no 10db peak at 1.2khz please!
Box will be 150L
I like this, but discontinued
https://www.usspeaker.com/beyma 18PW1400fe-1.htm
many thx!
many Faital 18s to choose from
http://www.loudspeakerdatabase.com/search/brand=Faital/18.0_size_in_18.0
http://www.loudspeakerdatabase.com/search/brand=Faital/18.0_size_in_18.0
its weird you mention it, since its one of the few that seemed to fit for my needs
however, they rate it as a subwoofer. this is one of the reason i didnt go with this one.
is there a difference between subwoofer and woofer? do you find the upper bass has detailed has woofers?
many thx
@youknowyou The 18pzb100 has a radius profile smooth cone and fairly low MMS for an 18 inch driver. The midrange is very clean and responsive. The small 4 dB peak is easily notched out with an LCR or offset xover slope with modified Q. The VC and motor are a very low distortion design with split coil windings and symmetrical motor. It's one of the few affordable 18s that have decent midrange IMO.
Will this be passive or active?
If a driver has a say 1k2 peak, why not just notch it out if everything else about the driver meets your needs?
passive
because my XO has only 2 coils and 2 caps, no resistors. I want to keep it that way by choosing proper drivers that allow 1st order xo.
While it's not a true midbass, it manages to convey decent low level detail at lower spls based on my listening experience. The combination of lower Rms, Fs, Qts with higher Qms and BL isn't usually found on an 18 inch PA driver of this build, especially ones with a double spider setup.
The Rms is the suspension resistance to movement (measured around 2.5 for this driver) and is one of the tell tale specs regarding your concerns. I listen to every cone driver with full range music in free air from various angles. That typically gives me all the info I need to weed out whats exceptional vs mediocre. A driver will tell you alot from this sort of evaluation, regardless of other tested parameters, specifically if the VC former isn't transferring most of its forward driving forces to the cone. You should hear very minimal treble bleed from the side of the VC through the basket windows. If so, expect alot of early midrange breakup and rolloff.
Many light weight VC formers (specifically unreinforced polyimide) aren't very stiff and can have radial breakup modes at various frequencies. This driver has a fiberglass VC former which is what I prefer aside from titanium or nomex.
The Rms is the suspension resistance to movement (measured around 2.5 for this driver) and is one of the tell tale specs regarding your concerns. I listen to every cone driver with full range music in free air from various angles. That typically gives me all the info I need to weed out whats exceptional vs mediocre. A driver will tell you alot from this sort of evaluation, regardless of other tested parameters, specifically if the VC former isn't transferring most of its forward driving forces to the cone. You should hear very minimal treble bleed from the side of the VC through the basket windows. If so, expect alot of early midrange breakup and rolloff.
Many light weight VC formers (specifically unreinforced polyimide) aren't very stiff and can have radial breakup modes at various frequencies. This driver has a fiberglass VC former which is what I prefer aside from titanium or nomex.
If you want to run this driver with a 1st order passive electrical filter, it will require a mild LCR notch to clean it up, unless you want to be forced to cross it in such a way that blends the small 1.6k peak into the filter slope.
I would just do a 3 - 4 dB notch at 1.6k and apply your passive filter, but I'd recommended a zobel to flatten the VC inductance. This can be combined to create an elliptical LP xover slope. It will depend on your midrange HP as well. Did you plan to sim the xover?
The only Faital 18 I'd consider for extended mid operation is the 18FH500. It will have an off axis only peak at 1.6 - 1.8k, making it sound less balanced on axis when notched.
Reality is just about every 18" driver will have a radial breakup mode peak at 1.6 - 1.8k due to the cone diameter. The severity will depend on cone geometry and dampening characteristics.
Reality is just about every 18" driver will have a radial breakup mode peak at 1.6 - 1.8k due to the cone diameter. The severity will depend on cone geometry and dampening characteristics.
even with a crossover point at about 300hz?
many thx for all your input. Very helpful
i agree a driver must sound nice unfiltered, before anything else.
No, I believe the higher price of the Faital doesn't translate into much better performance. If you plan on filtering the driver 1st order 300hz, the mid peak should be notched. It will be audible IMO without it, especially if you're as picky as I am with this sort of thing. You can certainly try it without and see if you notice. I suspect you will.
Faitals 18'' is good stuff, happy with them. I have not a standard application, they are mounted with a basket forward (which creates an additional low-pass filter) in OB and a crossover of 2nd orders of about 650, but I tried them above 0,8-1k and they performed well.
Issue with a first order filter at 300 hz is the peak will in theory still be only about 17 - 18 dB under the average level, which can be audible. The notch filter would make that inaudible. A 2nd order filter would be enough to bury the peak enough, but won't be satisfactory for the OP's needs.