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Multi-Way Conventional loudspeakers with crossovers

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Old 21st July 2009, 11:31 PM   #11
Telstar is offline Telstar  Italy
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Bravo!
Well done Jerome.

What's next?
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Old 21st July 2009, 11:57 PM   #12
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About the final sensitivity :

Efficiency
1 SLS315 = 90dB (above 300Hz)
2 SLS315 = 96dB

Loss
Inductor loss 0.4ohms = 1dB
12dB open baffle Equalization 300Hz to 70Hz

Thus I have 96 - 13 = 83dB / 2.83V / 1m.
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Old 22nd July 2009, 12:22 AM   #13
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Quote:
Originally posted by Telstar
Bravo!
Well done Jerome.

What's next?
I don't know ? Next Year ? I will not use a 5" on an open baffle, too much tricky. Perhaps make something with a 7" ? a much smaller OB, perhaps an active system ? I would just make a MTM ?
The HiFiNutNut project is bigger
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Old 22nd July 2009, 04:46 PM   #14
Elias is offline Elias  Finland
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Hello,

Passive full range dipole is very rarely seen. That makes your achievement even more remarkable. It's pleasing to see someone takes the hard way and goes passive.

What do you think is the inportance of the backside tweeter to the sound in your observations?


- Elias
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Old 22nd July 2009, 07:42 PM   #15
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Hello,

I always put a rear tweeter in my open baffle.
The improvements are in the treble. You double the surface of the treble and it seems more open, "bigger". You have a deeper soundstage and the instruments, the voices are more focused and more define in the space.
The level of the rear tweeter (0 to -6B) depends on the environment, for example, if the wall reflects a lot, you should have more attenuation.

Here in my design, I put 6dB, it 's discrete but enough.
In this passive design, I managed to use the same crossover for the tweeters. My first version used two crossovers, one for each tweeter.

I enjoy a lot with this design.

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Old 23rd July 2009, 04:11 AM   #16
CLS is offline CLS  Taiwan
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Hi,

Regarding the rear tweeters, I'm concerning the distance to back wall. Wouldn't the rear reflections interfere with thte front?

How far is your rear tweeter to wall?

CLS


PS. Nice speakers there, congratulations!
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Old 23rd July 2009, 06:01 AM   #17
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Hi,

Quote:
Regarding the rear tweeters, I'm concerning the distance to back wall. Wouldn't the rear reflections interfere with the front?
No it's a dipole, the panel is enough large, there is no wave cancellation in the treble. You will have interference between the direct and the reflected wave like all loudspeaker makes in a room.

Quote:
How far is your rear tweeter to wall?
1m.
This loudspeaker is not very different from an other in room placement. You don't have the benefit of the rear tweeter if the walls are too far, i think if the distance is superior to 2m.
I tried an open baffle, not this one, in an auditorium and the wall was at 3m. To have a better sound stage in the treble, we placed an other loudspeaker behind the open baffle (0.5m), Just to reflect earlier the rear sound.

An important note
The crossover schema have a mistake, the real wiring of the rear tweeter on the panel is opposite. Like this
Click the image to open in full size. Click the image to open in full size.
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Old 23rd July 2009, 07:37 AM   #18
CLS is offline CLS  Taiwan
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It's a good news! 1m is not very far. I'll try it on mine in the near future.
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Old 23rd July 2009, 09:56 AM   #19
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You should take a look to this linkwitz presentation :

http://www.youtube.com/view_play_li...laynext_from=PL (AES presentation)

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Old 23rd July 2009, 01:45 PM   #20
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Jerome,
amazing! congratulations
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