hi guys,
i don't udesrstand the utility to increase only the moving mass, the only difference between these models:
SB Acoustics :: 6” SB17NRX2C35-8
6" SB17NRXC35-8 :: SB Acoustics
in what application is more suitable the 2 version ?
i don't udesrstand the utility to increase only the moving mass, the only difference between these models:
SB Acoustics :: 6” SB17NRX2C35-8
6" SB17NRXC35-8 :: SB Acoustics
in what application is more suitable the 2 version ?
It looks like the engineers added ~2.9 grams of Mms which increases the Qts from 0.34 to 0.41, with the goal of getting slightly lower -F3 ported bass in a larger box volume(version2 0.7Qts requires 1cuft vs. 0.8cuft original) than the original, and accepted the slightly lower sensitivity.
Version 2 has T/S parameters which produce slightly deeper bass in a ported 1cuft Qts=0.7 cabinet.
Version 2 has T/S parameters which produce slightly deeper bass in a ported 1cuft Qts=0.7 cabinet.
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A few Satori speakers have a "measured flow" silicone/glue ring added to the rear cone near the outer surround to reduce cone breakup. The SPL curves for the SB17NRX2C35-8 show cone breakup similar to the SB17NRXC35-8. We would expect reduced upper frequency cone breakup if the extra 2.9grams of Mms in the SB17NRX2C35-8 was from a similar silicone/glue ring added to the SB17NRX rear cone near the outer surround.
Silicone/glue/goo on the SB17NRX cone to reduce breakup has not been openly reported by SBAcoustics.
Silicone/glue/goo on the SB17NRX cone to reduce breakup has not been openly reported by SBAcoustics.
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Based on the audioexcite measurements? Jury's still out on that one imo because audioexcite swept the NRX from 100Hz and the NAC from 200Hz. Other than higher 2nd order on the NRX which may well be an artifact from starting the sweep at higher excursion, they are basically the same.
The NRX seem to have a resonance issue at 1-2kHz, just like the Satori drivers which imo rules it out for 2-way operation.
ok, but fs of the 2 version is higher: 35 vs 32 (standard nrx version)
also, qts=0.41 but is too high for reflex box.
i think that nrx standard has quicker bass and goes low like nrx2 with a smaller volume.
nxr standard has also an higher qms
i continue not uderstanding the meaning of nrx2 version, i'm not realy expert
ok, but are you sure about this?
when could i find some photos ?
than you
intresting...but we must have some mesurements to show this...
i think the only chenge was added 2.9g weight
It's an extraordinary bass curve.
SB Acoustics :: 6” SB17NRX2C35-8
I have no idea quite how they have done that. And I don't know what sort of bass enclosure or filter will knock it into any really useable form. Unless LineSource has got it working with a simple reflex.
SB must have some idea where they are going with it. But I don't.
SB Acoustics :: 6” SB17NRX2C35-8
I have no idea quite how they have done that. And I don't know what sort of bass enclosure or filter will knock it into any really useable form. Unless LineSource has got it working with a simple reflex.
SB must have some idea where they are going with it. But I don't.
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if you are referring to nrx2 FR, i think too: this seems to me a plausible explanation
I happen to have measurements of SB17NRXC8 (not V2) in a 17 L closed box (23 x 37 cm front baffle).
Attached are raw and filtered freq responses. Also as a system with the mating tweeter (SEAS NoFerro650 with Visaton R148 WG).
Works well in a 2-way IMO, using steep LR4 filters and a peak notch.
Attached are raw and filtered freq responses. Also as a system with the mating tweeter (SEAS NoFerro650 with Visaton R148 WG).
Works well in a 2-way IMO, using steep LR4 filters and a peak notch.
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Ahh, right you are. I wasn't familiar with how that worked. I assumed ARTA had some kind of swept sine function. After playing around with it, it doesn't seem possible to make it step fast enough to get any appreciable crosstalk between frequency measurements.
I wonder why the higher 2nd order then? Maybe audioexcite had a faulty SB17 with a sagged suspension or wrongly magnetised motor. Or maybe the spider/surround have non-symmetrical Kms (old revision part?). I doubt the motor is different - I don't see any reason why SB would continue to use different parts for different SB17 models other than the cone. The cone itself will not affect bass distortion as it is well and truely a perfect piston at such low frequencies.
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