Yes, MANY harmonics are produced and at less than 1W/8 ! Show at typical 20-30W user level !
Dont buyers wonder why they only get shown Z, sensitivity and freq response tests data from driver mfr. But never distortions? Dont show negative data (marketing mantra).
I had a speaker system mfr send me a prototype Dynaudio 10 inch driver to measure its distortion. 20% THD at low power. The mfr took it back to measure. And this is a quality made driver by most standards.
It may be that freq response variations dominate what is most audible. But high distortion, compression, limited dynamic range, resonances et al also do NOT make for accurate sound.
THx-RNMarsh
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I do have connections. However, if you know what goes into making an accurate speaker/system you will know it by description if whether it is right or not. Everything JLB described about the M2 is what you want. Made only for the Mastering rooms and best recording audio and video studios. I didnt need to demo them against others which do not have the necessary characteristics for accurate performance. The only OK I got from JBL was to sell the M2 without the amps and sell me the speakers alone.
THx-RNMarsh
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No tricks,you said peer reviewed papers have nothing of significance in them. Unless they are just AES preprints which are not peer reviewed.
EDIT - I checked they both have extensive resumes, I doubt you have read much of it. In which case your comment is as insulting Waly's.
EDIT - I checked they both have extensive resumes, I doubt you have read much of it. In which case your comment is as insulting Waly's.
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Very good PMA. I am not at my home for another month. Would love to try it now.
I can only think some (Geddes, Scott etc) do not spend time critically listening. Or they would know better.
THx-RNMarsh
I can only think some (Geddes, Scott etc) do not spend time critically listening. Or they would know better.
THx-RNMarsh
Richard, that's patently insulting to Earl's body of work versus, as you've at least portrayed your own efforts as bush league at best.
Oh please, just read every years worth of AES papers. All peer reviewed and next year another batch finding yet another way to do same things are very popular. All good hard work also. Nothing much ever comes of any of it as far as useful product is concerned. I'll give Geddes he derived a more accurate way to determine directivity using certain Horns. Yet, is it significant in the market? other than his own constructs.... ?
Never-the-less, his poo-poo'ing of audible distortion(s) of drivers is not accurate at all. Good work focused in one place does not mean good opinions in another area. He lost a lot of credibility and potential customer. Good thing M2 was available.... a totally and thoroughly designed product of major significance to reproduction.
Take a look at the 'waveguide' used in the JBL M2 speaker. Has better directivity control. And, HOM's?
THx-RNMarsh
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It could have been even better. The technology was there and known. But there was a war going on between the Multimedia guys and the group that in my circles there, were referred to as the "box speaker guys". The multimedia guys had developed a super quiet port. The box speaker guys didn't want to use it because that would mean acknowledging the skills of the multimedia guys.
Here is the Patent the box guys passed up. US Patent for Speaker port system for reducing boundary layer separation Patent (Patent # 7,711,134 issued May 4, 2010) - Justia Patents Search
Better copy of the patent here: Patent US7711134 - Speaker port system for reducing boundary layer separation - Google Patents
Computer modeling of airflow keeps getting better. Advances in airplane wing design have also benefited.
Computer modeling of airflow keeps getting better. Advances in airplane wing design have also benefited.
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Have you seen the M2 port?
Large diameter, short ports have minimum issues. Small diameter, long ports are more trouble-some in generating port noise etal. Small diam ports are often seen in small cabinets often associated with computer/multi-media sound systems or other small enclosures.
I am long aware and so would be JBL known of that flared port patent and its utility... many compact speaker enclosures use it.
THx-RNMarsh
Large diameter, short ports have minimum issues. Small diameter, long ports are more trouble-some in generating port noise etal. Small diam ports are often seen in small cabinets often associated with computer/multi-media sound systems or other small enclosures.
I am long aware and so would be JBL known of that flared port patent and its utility... many compact speaker enclosures use it.
THx-RNMarsh
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I saw a presentation with cad drawings when the M2 was just released. I was the the one who turned you on to the M2 remember? Of course you didn't trust me at first and you had to wait until JC backed my recommendation up.
Where do you dream up this from? JC never told me a thing nor did I ask him re M2.
I went directly to JBL and M2 web for info. It had all the correct and needed design criteria for accurate repro. Thank you for turning me on to it. Until then I was using new Quads... which have similar performance in flat response, very low distortion, and controlled directivity.
But dynamic range of the ESL is too limited to sound 'live'. and Bass was limited and need a sub woofer . Still limited and compressed if pushed above 80-ish db spl at my listening place. Not suitable for large rooms but still does many things accurately. esp very low distortion. The M2 is all those things and better -- flat freq response, narrower dispersion, greater dynamic range, low distortion, deeper bass. Higher effec. Higher spl at low dist. Two way. [And dual large diam ports].
THx-RNMarsh
I went directly to JBL and M2 web for info. It had all the correct and needed design criteria for accurate repro. Thank you for turning me on to it. Until then I was using new Quads... which have similar performance in flat response, very low distortion, and controlled directivity.
But dynamic range of the ESL is too limited to sound 'live'. and Bass was limited and need a sub woofer . Still limited and compressed if pushed above 80-ish db spl at my listening place. Not suitable for large rooms but still does many things accurately. esp very low distortion. The M2 is all those things and better -- flat freq response, narrower dispersion, greater dynamic range, low distortion, deeper bass. Higher effec. Higher spl at low dist. Two way. [And dual large diam ports].
THx-RNMarsh
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My apologies you are correct! Who put that little paper in my coffee? http://www.diyaudio.com/forums/the-...owtorch-preamplifier-ii-8155.html#post4722234
re. large diameter ports, very little sound come from back side of a compression driver -- where as dome/cone have a lot of back wave freqs which can be heard at port output.... even with sound absorption material lining the inside of cabinet.
But, they put frosting on it by also flaring the port - their patented design.... perhaps judged to still be useful with high SPL drivers at low freqs. moving a higher than usual volume of air.
M2 Master Reference Monitor Products | JBL Professional
🙂
Their waveguide is also their own patent. By the looks of it, quite a bit of computer and software power was used. Significant results and potential for wider application.
THx-RNMarsh
But, they put frosting on it by also flaring the port - their patented design.... perhaps judged to still be useful with high SPL drivers at low freqs. moving a higher than usual volume of air.
M2 Master Reference Monitor Products | JBL Professional
🙂
Their waveguide is also their own patent. By the looks of it, quite a bit of computer and software power was used. Significant results and potential for wider application.
THx-RNMarsh
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