https://pdf.sciencedirectassets.com...=080f56575559025253&rr=8039b56e1850b8a3&cc=nl
This well documented survey gives the necessary information.
Conclusion is that only the "small granule" type has better properties than rockwool; a thicker layer of rockwool would equal a thinner layer of small granule aerogel sheet, so the aerogel sheet is good when room is restricted; otherwise just apply more rockwool or whatever "audiophile" stuff for the same absorbtion.
This well documented survey gives the necessary information.
Conclusion is that only the "small granule" type has better properties than rockwool; a thicker layer of rockwool would equal a thinner layer of small granule aerogel sheet, so the aerogel sheet is good when room is restricted; otherwise just apply more rockwool or whatever "audiophile" stuff for the same absorbtion.
There are three types for the granule size: small, medium, large. Only the small granule type is interesting as medium and large granule is not better than rockwool.
See screenshot of aerogel compared with rockwool, and conclusion.
See screenshot of aerogel compared with rockwool, and conclusion.
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490 usd for a square foot half inch thick tile....
http://www.buyaerogel.com/product/airloy-x103-large-panels/
http://www.buyaerogel.com/product/airloy-x103-large-panels/
Hi Endo,
I understand you intend to assemble a dipole system the M142P and double T34B. I think this is doable, kind of Linkwitz Orion.
I will replicate the LX-521//NaO Note II-RS with the M142P, double M74B and double T25B. Following recommendation from Linkwitz/Kreskovsky, of using the drivers (in dipole) to two octaves max.
So, 250-1K for the M142, 1-4K for the M74, 4K up for the T25. I have no reason to use the T34B (which I'm using now) the T25 is much better for this concept.
Both M74B are used with the back covers removed in a custom airtight, slim chamber, this allows for a minimal dome separation for a better dipole behavior.
We made a device (in PPN) to measure the double M74 and it works perfect, no issues with impedance, FR or distortion.
I was satisfied with what I have today, Supravox 215RTF (250-800Hz), Volt VM752 (800-3K), T34B. But this is monopole from 800Hz and I wanted to change this. Besides, the new Bliesma domes are simply unique.
I understand you intend to assemble a dipole system the M142P and double T34B. I think this is doable, kind of Linkwitz Orion.
I will replicate the LX-521//NaO Note II-RS with the M142P, double M74B and double T25B. Following recommendation from Linkwitz/Kreskovsky, of using the drivers (in dipole) to two octaves max.
So, 250-1K for the M142, 1-4K for the M74, 4K up for the T25. I have no reason to use the T34B (which I'm using now) the T25 is much better for this concept.
Both M74B are used with the back covers removed in a custom airtight, slim chamber, this allows for a minimal dome separation for a better dipole behavior.
We made a device (in PPN) to measure the double M74 and it works perfect, no issues with impedance, FR or distortion.
I was satisfied with what I have today, Supravox 215RTF (250-800Hz), Volt VM752 (800-3K), T34B. But this is monopole from 800Hz and I wanted to change this. Besides, the new Bliesma domes are simply unique.
Attachments
Hi Endo,
I have paid a simulation to VCLLabs. The polar radiation of the double T34 is not as good as the double T25. The overall diameter of the T34 is too big to be used in dipole.
The T25 is a much better tweeter for this concept. Of course a small dipole TW is perhaps better but, for several reasons, I do not like them.
I have paid a simulation to VCLLabs. The polar radiation of the double T34 is not as good as the double T25. The overall diameter of the T34 is too big to be used in dipole.
The T25 is a much better tweeter for this concept. Of course a small dipole TW is perhaps better but, for several reasons, I do not like them.
T34B has excellent dispersion for the size as that was an important design goal; dispersion is actually as good as T25B.
Left T34B; right T25B.
Besides, dispersion in a dipole is a matter of design choice; more HF dispersion does not make a better dipole.
Left T34B; right T25B.
Besides, dispersion in a dipole is a matter of design choice; more HF dispersion does not make a better dipole.
Attachments
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Yeah... crossing from an M142 to an M74 (probably at 600 - 1000 Hz) does not really use the full capability of the expensive M142.
As for woofers, a pair of SB34NRXL75-8 or a pair of ScanSpeak 32W/8878T01. A pair of 12" woofers would be approximately equivalent to an 18" driver.
Looks like the latest Marten uses both M74 and M142 (OEM carbon fibre)
https://www.marten.se/the-new-coltrane-quintet/
https://www.marten.se/the-new-coltrane-quintet/