Good morning, day or evening
Seas's prestige titan woofers are a rather interesting take on the modern style "small bass reflex enclosure, low efficiency, big bass" driver, and I would like to use one in a 2 way design. Being alu cones there's as per usual a nasty break up node to dodge. The driver I'd prefer is the L19RNX1:
H1878-08 L19RNX1
There is also the smaller 16cm with a slight higher break up but the higher sd and sensitivity is preferable.
Do you think crossing the L19RNX1 at 2000 Hz will be ok considering the breakup node? Will a 4th order be necessary to not make the node audible?
Seas's prestige titan woofers are a rather interesting take on the modern style "small bass reflex enclosure, low efficiency, big bass" driver, and I would like to use one in a 2 way design. Being alu cones there's as per usual a nasty break up node to dodge. The driver I'd prefer is the L19RNX1:
H1878-08 L19RNX1
There is also the smaller 16cm with a slight higher break up but the higher sd and sensitivity is preferable.
Do you think crossing the L19RNX1 at 2000 Hz will be ok considering the breakup node? Will a 4th order be necessary to not make the node audible?
Check the cone breakup thread on this, we did some job to round it up lately 😉
At 6kHz the breakup is prone to be excited by H3 of 2kHz. So discovering if the driver does a decent job at 2kHz is your first goal. Klippel tests on linearity of the motor system might give a hint. Luckily the folks at AudioXpress did the work for you. With H3 at 2Khz at a mere -30dB you'd have to push 2kHz some 10dB down from reference level to get -40dB or 1%. But as you can read, there's a lot of discussion about whether one can hear this or not.
At 6kHz the breakup is prone to be excited by H3 of 2kHz. So discovering if the driver does a decent job at 2kHz is your first goal. Klippel tests on linearity of the motor system might give a hint. Luckily the folks at AudioXpress did the work for you. With H3 at 2Khz at a mere -30dB you'd have to push 2kHz some 10dB down from reference level to get -40dB or 1%. But as you can read, there's a lot of discussion about whether one can hear this or not.
Response doesn't look smooth enough for 2-way desing, to my eyes.
Zaph's L18 2-way was popular, it's worth studying anyway (I had those)
Zaph|Audio
Zaph's L18 2-way was popular, it's worth studying anyway (I had those)
Zaph|Audio
Yes, the smoothness is another thing. Too bad they did make paper cone versions of the titan drivers... The article mentioned by Markbakk also seemed to indicate that this was a 3 way + type of woofer.
But what about the L16RNX3? It's not much, but slightly smoother. And the breakup doesn't start before some 7200 Hz, although, it becomes pretty violent after that.
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But harmonic distortion is usually a non-linear distortion. So if the driver is down to -10dB at 2kHz, that not necessarily means the HD level is down by the same 10dB. I have seen examples where the H3 was higher in percentage at lower SPL compared to higher SPL.
But yeah, audibility is a good question.
H3 can be caused by nonlinear but symmetric motor and spider behavior (among others, but these two are dominant). That most of the time has a relation with the amplitude of the cone movement: the higher the excursion, the more nonlinear the output, resulting in (not only) H3, H5 and H7 products. In most cases, higher level leads to higher distortion ratios. But I'd not trust the assumption and rather measure myself.
Actually, I think you interpret the word 'nonlinear' not totally right here. We discern linear distortions and nonlinear distortions. The former usually address to e.g. level vs frequency, the latter could be that a system produces multi spectrum signals while fed with only one or two frequencies (HD and IMD).
Actually, I think you interpret the word 'nonlinear' not totally right here. We discern linear distortions and nonlinear distortions. The former usually address to e.g. level vs frequency, the latter could be that a system produces multi spectrum signals while fed with only one or two frequencies (HD and IMD).
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That could stem from the measurement technique SEAS uses, what you see is the baffle step of the measurement box. SEAS doesn't use the IEC baffle. This was discussed recently somewhere here but SEAS publish their measurement protocol rather briefly on their site.
Hmm, I have a cone driver that produces less percentage of H3 at higher SPL than lower SPL.
I think non-linear distortion means that it changes it's percentage at different SPL, so the scale are not linear with the level change.
Linear distortion (e.g. frequency response anomalies, phase distortion etc.) stays at the same percentage at different SPL.
The relation original signal - distortion seldom is linear. Sure you weren't measuring noise? But your findings could be correct: if you look at the causes, e.g. nonlinear drive characteristics, they could show a pattern that could bring out what you are measuring, purely by accident. But I doubt that this driver will perform better at every higher level.
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Just the H3 at a relative small range that beheave like this, the H2 (dominates mainly) for example shows more percentage at higher levels and of course it's almost sure there be an upper limit where the H3 begins to ramps up but I don't really want to know at what level, because it's already too loud for normal home listening. It's a pro sound driver btw.
L18
W18
And L19 is a woofer for 3-way speakers, look at low bass response and surround!
An externally hosted image should be here but it was not working when we last tested it.
W18
And L19 is a woofer for 3-way speakers, look at low bass response and surround!
An externally hosted image should be here but it was not working when we last tested it.
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atleast it will be better than the regular L16. where zaph recommends a 1.4khz 4th order crossover:
Zaph|Audio
Yes the other L16s are even trickier. However they have apparently been used to great effect by Linkwitz and Joseph audio in 2 way designs. It's all a matter if integration I guess.
Yes, at SEAS: The Art Of Sound Perfection when you move mouse above response graphs, an info box opens up. 28Liter closed box, but baffle dimensions are not given. Based on response I guess it is most likely square box, because baffle step peak and minimum are so prominent.
Attachments
Oh yes, I've seen that before too.
Strange, this L19 is said to be measured in 28 liter box, but pdf chart tells that 7" driver's box is 12 liter, and baffles respectively hugely different size...
Strange, this L19 is said to be measured in 28 liter box, but pdf chart tells that 7" driver's box is 12 liter, and baffles respectively hugely different size...
Well, you know how it goes at the lab.
"Wait, we need the 12l enclosure for 7" speakers!"
"Oh but no, someone forgot to dismount the last driver on test..."
"Well never mind, the 28l is available, let's take that one!"
"Wait, we need the 12l enclosure for 7" speakers!"
"Oh but no, someone forgot to dismount the last driver on test..."
"Well never mind, the 28l is available, let's take that one!"
Hi
In my opinion, the L19RNX1 is a typical woofer. It is a real alternative to Scan Speak Illuminator 18WU8747.
I bought these drivers and will be building a 3way with Seas 2xL19RNX1 + Satori MW16Textreme + Bliesma T25B. It will be similar to this:
In my opinion, the L19RNX1 is a typical woofer. It is a real alternative to Scan Speak Illuminator 18WU8747.
I bought these drivers and will be building a 3way with Seas 2xL19RNX1 + Satori MW16Textreme + Bliesma T25B. It will be similar to this:
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
