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What is the appeal of open baffle?

FrantzM

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No Genelec speaker has any sort of directivity control at low frequency, they’re not even directive lol.
By themselves, no. “The Ones” + W371 woofer system , however, is able to bring controlled directivity down to 100 Hz or even lower IIRC.
 

anmpr1

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Novice question: What are musical instruments - dipole or monopole? Does it vary by instrument type? (wind / string / percussion)
There is an ASR thread somewhere containing a link to a site featuring recordings of various instruments using mikes at different locations (heights and distances) around the instruments. Worth hunting down, probably.

Different instruments are going to have different radiation patterns, and the same instrument will show different patterns depending upon the location of the listener. In one study (also linked in an ASR thread somewhere) a kettle drum is shown to sound subjectively omnidirectional in the farfield, however up close the drum's perceived sound pattern is more directional.

That said, how any single instrument projects sound is not necessarily important to a loudspeaker in a home environment. I may have interpreted him wrong, but in the above post linking to his Website, S. Linkwitz starts with the proposition that the ideal reproducer is a single sphere, radiating omni throughout the listening environment, which is, of course, unrealized in practice, and other factors come in to play that necessarily delimit this sort of 'ideal' radiation pattern:

"The ideal monopole is omni-directional at all frequencies. Very few speaker designs on the consumer market approach this behavior. This type of speaker illuminates the listening room uniformly and the perceived sound is strongly influenced by the room's acoustic signature. The result can be quite pleasing, though, because a great deal of acoustic averaging of the sound radiated into every direction takes place. The speakers tend to disappear completely in the wide sound field. Unfortunately, the direct sound is maximally masked by the room sound and precise imaging is lost, unless the listening position is close to the speakers."
 

Newman

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I don’t think SL was saying an omni sphere is the ideal loudspeaker. He is just explaining what the word monopole, ideally, means.

Like he says in your quotation, the direct sound is lost, and that is “unfortunate”. And you are left listening to the room sound, and in a highly averaged way that no natural reproducer (voice, common instrument) does.
 

suttondesign

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You have got to experience Linkwitz LXmini and LX521 to believe them. I built Orions too. I have never heard better, though the Dutch 8c are very fine in their way.
 

JWAmerica

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The Orion is a beautiful speaker. The upper baffle on the LX521 is so unaesthetic I would need to make a grill to hide it.
 

anmpr1

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I don’t think SL was saying an omni sphere is the ideal loudspeaker. He is just explaining what the word monopole, ideally, means.

Like he says in your quotation, the direct sound is lost, and that is “unfortunate”.

He was, as you point out, discussing the monopole from an 'ideal' standpoint. One thing: to attempt to distill SL's ideas into a sentence or two is a mistake neither I, nor anyone else, should attempt.

What is certainly unfortunate is that he is no longer with us to provide insights. One of his last:

"I make the claim that loudspeakers and room can disappear from the AS [acoustic or auditory scene] and that this depends primarily upon the polar response of the loudspeakers and their setup in the room. Loudspeakers must be free-standing and at least 1 m away from adjacent walls. Loudspeakers and listener form an equilateral triangle that is situated symmetrical to the walls... Greater listening distances... may suffer from diffuseness of the sound stage, but not necessarily in plausibility of the AS.

I also claim that constant directivity as approximated by
[his then working speaker, the Orion] for a dipole, and by [the Pluto speaker] for an omni-directional source, provides more often a plausible AS from commercial recordings, than the conventional box loudspeaker with its strongly frequency dependent radiation pattern. But I do not know if there is a more optimal solution than a dipole or omni. Should it be cardioid or which polar pattern is good enough?"


http://linkwitzlab.com/orion++.htm
 
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