+/-14,5mm, but as always, it depend on your definition of xmax ^^
Factory said there's really big and long aluminium demodulation rings. 12NSW600
In fact, i see it as a bms 12s305, with less cone resonnance, with a big triple roll surround that should help to go low. It's a new version with sandwich surround, as done with spiders, it's not in datasheet.
It is made on order, so it's somewhat a bit pricey, at 233 €.
I inquired about these a couple years ago. They were a bit much for me at the time. I do wonder about power compression with that kind of xmax and the power to reach it when tuned around 40hz. Had some issues with BMS in summer temps. All that aluminum should help though.
Wish they had U.S. presence. High quality looking stuff.
On russian forum :
"there were no speakers on the market that met these requirements. By trial and error (within 1 year, our 12 pieces flew to shreds first from 1000 watts, then from 2000 watts), we were finally able to get a 12NLC60V speaker, which passed the test F = 30-300Hz for 13 hours with an amplifier 5600W (half amplitude 300v from two amplifiers included in the bridge). In this case, Mms = 87.1 g., BL = 20.41 TM, BL / Mms = 234.31 TM / Kg."
12nlc60v is the old name of the 12nsw600 (as show in measurement done the 21.08.19 by oberton when asking measurement of 12nsw600).
Thanks for the info! Sounds very encouraging for the development of small subs that are deceptively powerful.
Seems like they might be able to do custom impedance since they are built to order. I would like to use one with the large RAM audio 3-way plate amp. It provides 3000w into 4ohms at an undefined time spec. Want to use it as a full range compact prosound monitor. I already have a Beyma 8MC500 and Radian Neo745.
Ran the sims again. 1500w is enough to pass xmax in a 1.5ft(42L) box tuned to 45hz with 3db eq boost below 100hz.
Kind of forgot about this driver. Now that there is a plate amp available to buy that meets the specs I wanted, I can make real good use out of these for a small footprint design. Ultimate small PA in a box for smaller situations.
From what i remind having readen (weird sentence, do it make sense ? ^^), -but my memory is not really reliable - the used amplifier for test in the russian forum linked has some specific protection feature
Received - mesured ! This is a monster ! Picture 1 is measured with limp, with added mass method with 47g neo magnet for black curve. Magnet placed only on one side of the cone seems to add some problem around 150hz that doesn't need to worry about. I used multitone limp method, since i get same result with the other way more noisier method. I tested different small signal level (1-4Vrms), and it didn't change the curve look.
Lower Re, lower inductance, higher fs, lower VAS => but in sim, it make almost no difference in my pseudo 6th order project.
During breakup, i verifyed it did -/+15mm (easy to verify) with my little composite bridged lm3886 at +/-70w, around 60Vpp, @ 14hz during few hours (in multiples times because wires of my ugly test gig becomes hot ^^). (picture 9 was at 53vpp/12hz)
Breakup gig pictures for fun
I think I've found the one "workbench" that's messier than mine, LOL. When I start work on something, by the time I'm finished it looks like several hurricanes swept through there. I've spent the last two Saturdays just cleaning crap out of the cupboards...
Nice parameters on that driver, BTW. Looks like it's going to be a little monster...
Yes ! I played with a serie 6th order with a PR for high way and dual reflex for low end (dual port in serie with intermediate chamber as damping stub). Dual reflex in serie allow shorter ports, so playing with resonnances at higher frequency. It work well, but i need to finish the box. I'll post when finished.
In fact it will be dressed as a Ampeg bass cabinet. I got everything, corners, handle, tolex, grillcloth...but for the moment, it's only a ugly wood box.
I removed dogs cuddy toys used for damping test for photos
It's made of 10mm ply + butyl putty // plastic acrylic low elastic modulus putty + 2 mm hardfibers, and lot of crossbrassing using what i had under my hands, mostly oak and hardwood. It's a hard and not that much resonnating box. I expect tolex glued with sikaflex will help damping too.
Not seen on photo is the 11 liters front chamber between oberton and the css passive radiator. I did fast and ugly fiberglass/polyester roundover for ports.
I added too butyl putty to passive radiator chassis, since it resonnated a lot. This thing is so effective.
Back panel access was really convenient to tune port lenght, and it will be again to tune better damping materials when i'll have time.
Left and right chambers on photo are in fact as stub more or less at middle of one vent. Back pressure get from back chamber to side chamber through first pair of ports, and goes outside box on front through second pair of ports. So that lenght of port is kind of splited, and resonnance damped with side chambers. This help to sculpt response. I didn't invent anything. All i did was playing with Hornresp sliders.
As expected, i had a kind of crossover distortion like effect that i tweaked between direct PR response, and port output. As expected from sim, those resonnance are nulled simply by tuning PR weight. I had hard time to modify the css apr12 to get i moving mass reduced to what i expected : PASSIVE RADIATOR SURGERY
From recording with REW, i had a stupid resonnance from the too much cubic back chamber. I'll have to test separator + magic sponde melamine damping.
While running fullrange the driver in box compared to test free air, the bandpass effect is impressive...almost no need of low pass. At first tests high level low frequency, it did scray noise that was in fact simply coming from badly screwed screw air leak.
Here i posted the first measurements set without any filter, and really badly tuned, before passive radiator surgery. There was the 75hz expected hole from port output occur that is now totally nulled now : FIRST SET OF MEASURMENTS
Some will probably ruch too fast that one 12" PR is not enough, but goes wrong, since lows are output from ports in the present case. Passive radiator is only used as excessive solution for low pass/distortion filter for front chamber. So even with 60vpp it doesn't exceed +/- 12mm. Of course, the oberton could get way more power. But it wasn't what i wanted for this project. The 12nsw600 is really a excessive solution for the few hundred watt i'll give him.
For the moment, i have not that much time to work on it. You'll have to wait !