hey Guys,
I´ve looked at those PDF Document from 18Sound or RCF and read that there is a Peak to Peak excoursion limit givien.
for example:
18Sound 18W1000 Xlim -> 36mm One Way
18Sound 18NLW9600C -> 70mm One Way
when i look at the suspension i can not imagnine that those PA Speakers are able to do those excoursions without getting damaged.
I want to know if I can take the disclosures seriously?
and a second question, is the diagramm displacement in hornresp one way or the total excoursion?
I´ve looked at those PDF Document from 18Sound or RCF and read that there is a Peak to Peak excoursion limit givien.
for example:
18Sound 18W1000 Xlim -> 36mm One Way
18Sound 18NLW9600C -> 70mm One Way
when i look at the suspension i can not imagnine that those PA Speakers are able to do those excoursions without getting damaged.
I want to know if I can take the disclosures seriously?
and a second question, is the diagramm displacement in hornresp one way or the total excoursion?
I'm sure that's not correct, I'd imagine cutting those in half would be closer and on the second one, not even then... Perhaps that's how far it can travel without damage both ways, in terms of hitting a backplate, but I would doubt the suspension even lets it get that far.. Just a hunch on the second driver, but I'd imagine the real usable displacement on both those drivers is less than 25mm. Probably 16mm and 25ish, respectively. You don't see many pro audio with actual displacement's higher than that. Even my B&C 21 which is rated at 60mm before damage (both ways) only has 15mm of xmax and the suspension puts some heavy brakes on around 22mm, you can't bottom it without ripping the spider first.
So maybe, 36mm (about 19mm each way) total displacement are real?
okay Hornresp say its Mean-to-Peak displacement, maybe i have to look first in hornresp help next time^^
okay Hornresp say its Mean-to-Peak displacement, maybe i have to look first in hornresp help next time^^
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yeah, that's around the limit for pro audio drivers, at the moment. I believe TC sounds did a 5100 pro that had xmax at 30mm or higher, but when tested, the suspension was noisy past 25mm or so, fwiw.
You can take them seriously if you read them correctly 😉.
The 18Sound 18NLW9600C spec sheet states a 70 mm max peak to peak excursion, not "One Way".
The speaker will be damaged if one attempts to exceed 70 mm peak to peak.
For whatever reason, likely to make Xlim sound bigger, it is often presented as a peak to peak figure, when it should be one way, as is Xmax.
The 18NLW9600C has 14mm Xmax, which is 28 mm peak to peak, +/- 14mm, (the distance you will see a white dot on the cone move at Xmax) about half of the Xlim figure.
Where one gets in to trouble is with speakers where Xlim is only slightly longer than Xmax, one popped bass string can cause an abrupt end to the voice coil banging on the back plate, or a ripped spider or surround.
Attachments
Distortion above Xmax increases a lot. So one can use a driver past Xmax, it is wise to not exceed it by too much however.
I am sorry , but maybe you should read the technical specification sheets of the drivers correctly.
18W1000 has: 36 mm Peak to Peak and linear Xmax from 14 mm Peak to Peak
18NLW9600c has: 70 mm Peak to Peak and linear Xmax from 28 mm Peak to Peak
When you look you will find Prodriver that are able to do much more linear ercursion, like the BMS 18N862 with 19 mm linear excursion in each direction, or the Aura NRT-18 with 18 mm in each direction! The TC Pro5100 has a Xmax from 19 mm in each direction and a maximum excursion of around 76 mm.
18W1000 has: 36 mm Peak to Peak and linear Xmax from 14 mm Peak to Peak
18NLW9600c has: 70 mm Peak to Peak and linear Xmax from 28 mm Peak to Peak
When you look you will find Prodriver that are able to do much more linear ercursion, like the BMS 18N862 with 19 mm linear excursion in each direction, or the Aura NRT-18 with 18 mm in each direction! The TC Pro5100 has a Xmax from 19 mm in each direction and a maximum excursion of around 76 mm.
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Okay, im sorry, im from germany, did not understand what the pdf say ^^
Now i know that Peak to Peak isnt mean to peak^^
Now i know that Peak to Peak isnt mean to peak^^
I am also from Germany, so when you have a question in the future I think then I could help you if you want!
Greets
Frank
Greets
Frank
that is exactly what it means
70mm peak to peak = 70mm P-P
equals 36mm one way = +/- 36mm
but it is always nice to know pole thickness and voice coil length
just a note of caution
36mm Xmax could be very close to 'Xmax before damage'
in case of the 18 nlw 9600, 36mm is damage point .you want to stay below that point(it wil sound verry distorded comming close to 36 mm)
there are differend ways manufacturers calculate x-max figures.
some measure distortion levels,some use a % of bl point.
some just calculate hvc-hg/2(bms is one of them).
on the other hand x-lim is fixed for sertain type of driver,beond that and the driver wil be destroyed.
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As far as my understanding goes, the figure quoted as Xmech (P-P) by most manufacturers = distance from the end of voice coil former to the bottom plate x 2.
So, Xmech is easy to work out, and in my experience with PA drivers from the likes of 18Sound, Volt and Beyma, accurately quoted on spec sheets. In the real world, however, it's not that useful to the end user, unless the main aim is to hit high SPL's (Pro Audio and ICE being the main offenders!), where drive units with a large Xmech are very desirable, and distortion often a factor that is compromised.
So, Xmech is easy to work out, and in my experience with PA drivers from the likes of 18Sound, Volt and Beyma, accurately quoted on spec sheets. In the real world, however, it's not that useful to the end user, unless the main aim is to hit high SPL's (Pro Audio and ICE being the main offenders!), where drive units with a large Xmech are very desirable, and distortion often a factor that is compromised.
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