My last project was building a Nao Note II RS after many possitive open baffle experiments. I like the Nao Note II RS a lot, when I crank them up is like being at the venue.
Over the past 10 years I have ammased lots of drivers and gadjets for more experiments, too many
During that time I acquired aprox 130 Sawafuji dipole tweeters that I have used for many experiments. I made headphones out of a pair of them. Ive always wanted to make an array and now I am motivated to do so.
For the Nao Note I am using a Najda DSP and purchased a pair of Outlaw Audio 5 channel amplifiers. I am quite happy with both.
I am looking to build a a 2 way or three way depending on array arrangement. The lows some type of eq'd sealed unit and try to cross it as low as the array can handle.
Have 50 units available for each speaker and was thinking a 5x5 Array for the Highs and a unshaded 5x5 array for the low mid to get the most out of the "tweeter". As headphone elements they sound quite good.
I have read threads about Bessel arrays but none mention dipole elements. Would the shadded array also display single source dipole behaviour?
Am I better off using 4 channels of the DSP and doing something else shadingwise? The fifth channel is reserved for the lows.
Or am I better off with a 2 way with all 50 connected unshaded as a single panel?
Over the past 10 years I have ammased lots of drivers and gadjets for more experiments, too many
During that time I acquired aprox 130 Sawafuji dipole tweeters that I have used for many experiments. I made headphones out of a pair of them. Ive always wanted to make an array and now I am motivated to do so.
For the Nao Note I am using a Najda DSP and purchased a pair of Outlaw Audio 5 channel amplifiers. I am quite happy with both.
I am looking to build a a 2 way or three way depending on array arrangement. The lows some type of eq'd sealed unit and try to cross it as low as the array can handle.
Have 50 units available for each speaker and was thinking a 5x5 Array for the Highs and a unshaded 5x5 array for the low mid to get the most out of the "tweeter". As headphone elements they sound quite good.
I have read threads about Bessel arrays but none mention dipole elements. Would the shadded array also display single source dipole behaviour?
Am I better off using 4 channels of the DSP and doing something else shadingwise? The fifth channel is reserved for the lows.
Or am I better off with a 2 way with all 50 connected unshaded as a single panel?
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Hi, this kind of arrayed baffle works as monopole, but you will get in serious trouble with dipole.
Dipolic radiation pattern is determined by baffle dimensions vs. wavelength. If a baffle like that is say 15" wide, it will radiate as symmetric dipole only sideways up to 1000 Hz. Size and number of drivers is irrelevant below that. Above that you will get extreme directivity and a jungle of interferences if all drivers radiate. In vertical dimension this is exaggearated!
A 2-way with the center drivers highpassed gives better frontal directivity, but radiation pattern is not exactly dipole or constant any more. Just like with large panel speakers... and many poeple like that. I am sure that the sound will be different from NaOs! How well these work in a room is yet another story.
This was just theoretisizing, please make a test mule and report your findings!
Dipolic radiation pattern is determined by baffle dimensions vs. wavelength. If a baffle like that is say 15" wide, it will radiate as symmetric dipole only sideways up to 1000 Hz. Size and number of drivers is irrelevant below that. Above that you will get extreme directivity and a jungle of interferences if all drivers radiate. In vertical dimension this is exaggearated!
A 2-way with the center drivers highpassed gives better frontal directivity, but radiation pattern is not exactly dipole or constant any more. Just like with large panel speakers... and many poeple like that. I am sure that the sound will be different from NaOs! How well these work in a room is yet another story.
This was just theoretisizing, please make a test mule and report your findings!
Thanks Juhazi,
You are right, I will have to experiment. Started, will try getting horizontal responses at multiple angels to see how it behaves.
I already put some music through it and the tweeters sound like a mid. I had done tests a while back with a paraline array and it it went down to around 400 hz. Not sure if the full dipole cancelation is there, I have them in the Kitchen and the music is everywhere, when I stand at the 90 degree position the cancellation is not as obvious, it actually sounds like a pseudo stereo. Pretty sure I am hearing the reflection.
Next some measurements.
You are right, I will have to experiment. Started, will try getting horizontal responses at multiple angels to see how it behaves.
I already put some music through it and the tweeters sound like a mid. I had done tests a while back with a paraline array and it it went down to around 400 hz. Not sure if the full dipole cancelation is there, I have them in the Kitchen and the music is everywhere, when I stand at the 90 degree position the cancellation is not as obvious, it actually sounds like a pseudo stereo. Pretty sure I am hearing the reflection.
Next some measurements.
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First quick measurement
To my surprise, it is omni. Thats is why i heard music everywhere. Will do it a second time to see if the results are the same. BTW, nothing fancy, measuring inside the house, away from walls and at 45 degrees,back points to a hallway.
To my surprise, it is omni. Thats is why i heard music everywhere. Will do it a second time to see if the results are the same. BTW, nothing fancy, measuring inside the house, away from walls and at 45 degrees,back points to a hallway.
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Below 500Hz we see dipole loss, dipole/baffle step peak at 500Hz, dipole radiation goes off at 900Hz (and radiation is practically omni). Above it radiation is bipole, above 6kHz drivers are beaming increasingly.
https://pdfs.semanticscholar.org/460d/1b61e116d50ad3ed136152d8176e9984c28e.pdf
Dipolplus - Alles über offene Schallwände
https://pdfs.semanticscholar.org/460d/1b61e116d50ad3ed136152d8176e9984c28e.pdf
Dipolplus - Alles über offene Schallwände
Outside measurements today. The gated and non gated are not that far off
The room in the house is aprox 22 feet wide x 45 feet long
BTW had a listening session with the NAO II RS on friday, volume high enough as if you were there in the venue, awesome! Listening standing up (while dancing) in the middle of the room.
I might just give it a go an make one of the arrays with 50 units, maybe 60. I have to figure out the best series/parallel combination.
The room in the house is aprox 22 feet wide x 45 feet long
BTW had a listening session with the NAO II RS on friday, volume high enough as if you were there in the venue, awesome!
Listening standing up (while dancing) in the middle of the room.I might just give it a go an make one of the arrays with 50 units, maybe 60. I have to figure out the best series/parallel combination.
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