Look at this page instead - it is the nrx2 new version
https://sbacoustics.com/product/4-sb12mnrx2-25-4-norex/
What are objective and subjective pro's and con's of going from the 12" woofer to a 5" vs 4" midrange?
I get that "subjective" is almost like asking opinions on expensive capacitors, but can be still relevant. Just looking at a few of the 5" drivers, they have about 60% more Sd than a typical 4". I have no strong personal opinions, but I know people who think the 5" (or even 6") are better able to accurately produce some vocals and instruments. Let's not de-rail too much, but I think it is worth discussing.
Edit: the question is meant for everyone, not just mikessi who I quoted.
There is no naming convention for drivers across brands.
The SBA mentioned above has 123 mm (5") exterior basket diameter. Dayton would call that a 5" driver.
Yes, and in fact it is listed as a 4" driver at Madisound but 5" somewhere in Europe that I looked (but don't remember which site). I tend to look at Sd to get an "typical" 4-inch and 5-inch driver. (For example, the Dayton Reference Series woofers are listed as nominally about an inch bigger cue to frame diameter than other woofers when looking at Sd.)
So, most of the 5" drivers in my "short-list" are about 60% more Sd than the SB12MRNX - whatever size we want to call it.
So, most of the 5" drivers in my "short-list" are about 60% more Sd than the SB12MRNX - whatever size we want to call it.
Significantly lower Sd and smaller voice coil in sb12mnrx2 than in other mentioned midranges. If crossed to a 12" woofer, i wouldn't let it do much below 400Hz.
I think that finding a woofer that can be crossed at 400-500Hz would be beneficial since the crossover is cheaper the higher in frequency you move the crossover point. That's one of the reasons why Wharfedale Linton bass to mid crossover point is at about 600-650Hz.
I still think that 12FE330, 5fe120 and any decent tweeter would make a hell of a threeway. In budget version i would strongly advise to stay away from closed cabinets for woofers. All good woofers that can work in a closed cabinet are expensive.
Also, given that price is a very important factor for drivers, i would want my midrange to be as sensitive as possible - without upper limit for sensitivity actually. It is one thing to force a midrange that is 85dB/2.83V/1m to play 90dB at 2m distance and tottaly other thing to force a 92dB/2.83V/1m to play at that volume. Distortion can creep in quite fast.
I think that finding a woofer that can be crossed at 400-500Hz would be beneficial since the crossover is cheaper the higher in frequency you move the crossover point. That's one of the reasons why Wharfedale Linton bass to mid crossover point is at about 600-650Hz.
I still think that 12FE330, 5fe120 and any decent tweeter would make a hell of a threeway. In budget version i would strongly advise to stay away from closed cabinets for woofers. All good woofers that can work in a closed cabinet are expensive.
Also, given that price is a very important factor for drivers, i would want my midrange to be as sensitive as possible - without upper limit for sensitivity actually. It is one thing to force a midrange that is 85dB/2.83V/1m to play 90dB at 2m distance and tottaly other thing to force a 92dB/2.83V/1m to play at that volume. Distortion can creep in quite fast.
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The SIG180 looks even better. Costs $10 more. https://www.parts-express.com/Dayto...ure-Series-Woofer-80W-Driver-4-Ohm?quantity=1
Is it not the same if you need to pad down with a resistor the 92 db mid to 85 db to meet the woofer ?
For sure, it's effective Sd that matters, not the "specified" size.
The 50cm2 of the SB12MNRX2 is probably a big reason why @profiguy rated it tops -- dispersion will narrow at a higher frequency than most other "5 inch drivers", which are mostly 85~90cm2.
I think even 400Hz is too low for this driver.
And to answer the question of 5" vs 4" midrange, I would vote for a larger mid driver to better manage the lower end of its range. We have tweeters than can be crossed <2.5kHz.
PS -- interestingly, many SBA drivers have lower Sd for their specific size. For example, Satori MR13 (13cm or 5.3") is 70cm2. Faital 5FE125, same diameter, is 84cm².
The 50cm2 of the SB12MNRX2 is probably a big reason why @profiguy rated it tops -- dispersion will narrow at a higher frequency than most other "5 inch drivers", which are mostly 85~90cm2.
I think even 400Hz is too low for this driver.
And to answer the question of 5" vs 4" midrange, I would vote for a larger mid driver to better manage the lower end of its range. We have tweeters than can be crossed <2.5kHz.
PS -- interestingly, many SBA drivers have lower Sd for their specific size. For example, Satori MR13 (13cm or 5.3") is 70cm2. Faital 5FE125, same diameter, is 84cm².
The opposite from the Reference Series, the Signature Series have relatively large Sd for their nominal size. This is good for moving more air (especially in a two-way), but bad from a directivity perspective. I think a major weakness of the original classic 3-ways was poor directivity so that is a specific area we want to pay attention to.
That is exactly my point. When i turn the volume up on my loudspeaker, i like temperature rise to reside in my resistor not in my voice coil. I can quite cheaply and easily over-dimension my resistors (if 20W is enough, i'll double it to 40W) but i can't do it for my voice coils. Power compression is much more easy to detect than HD2 and HD3 when listening to music.
Protecting the midrange and tweeter voice coils from over-heating was (and still should be) a very important goal, especially in a budget loudspeaker. First condition this loudspeaker should fulfill is to work every time. When that condition is met, then we can assess the sound and measurements.
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From researching several forums, the FaitalPRO 5FE120 sounds very good and has exceptional off-axis behavior.
So another way of asking the question regarding midrange choice... For a budget 3-way build, with the Peerless 12" 830669 as the woofer, is there a driver that is a better choice than the 5FE120?
So another way of asking the question regarding midrange choice... For a budget 3-way build, with the Peerless 12" 830669 as the woofer, is there a driver that is a better choice than the 5FE120?
Good thing about 5FE120/5FE125 (other than it's performance) is that it is made by a pro loudspeaker company. That means that it will be used in pro audio (small transducers are usually used in line arrays) so it will be produced in vast quantities - which almost always ensure widespread and long term availability and low prices.
I don't quite follow. Are you saying the off axis when mounted on a 13"to 16" wide baffle is going to be any different between the two sizes? What does the desired off axis look like? Are the differences near the 1k to 3k range?
Not sure if this is some sort of a mixup.
The baffle step is concerned with the on-axis SPL, and it describes the transition from 2pi to 4pi. 2pi corresponds to wavelengths much shorter than the baffle dimensions, and 4pi correcsponds to wavelengths much longer than the baffle dimensions.
The power response is the total output emitted from the speaker, which is independent of direction.
Don't be fooled by the factory FR graph on the SB mid. Its significantly better than the 5FE120 and 5FE125 in a few ways.
The Faital mids have higher 3rd order HD across the board. They suffer from a pinch resonance from the inverted dust cap attachment junction. The motor isn't as linear. The basket is also cast, which helps shed heat in a small chamber.
The SB12MNRX2 is a phenomenal deal for the price. It can be crossed higher without as much off axis misbehavior up to the cutoff. You can even see this in the factory FR curves, despite the extra smoothing and scale compression the Faital.
Crossing the mid lower may appear to be beneficial on paper for several reasons, but it has other negative consequences and defeats the purpose.of building a 3 way that has a dedicated mid. You want most of the mids.to come from the midrange for several reasons. A sub - 2.5 k turnover to the tweeter hurts SPL capability and makes the tweeter sound rougher to the ears, especially at higher volume.
A 350 hz 2nd order filter is totally within the capability of the SB12MNRX2. It will do mid 100s dB crossed this low and outperform the Faital in almost every way, plus its easier to flush mount.
The only place where it may be slightly outdone is in the overall power handling department, but its very slim. Most SB drivers are severely under rated in power handling. Power compression isn't a problem crossed 300 to 350 ish hz. The basket does a good job at shedding VC heat within reason, but it won't be as stressed as the Faital thanks to slightly higher sensitivity.
The SB12MNRX2 is simply just a better sounding driver than any other similar priced, currently available mid. The only smaller, significantly lower sensitivity mid I could think of is the Peerless 830870. Its only 86 - 87 dB / 2.8V and handles 30 - 35 w continuous. Its also harder to find in small quantities. If you were building a smaller 10" LF 3 way, this is the right mid.