Passive Radiator

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Latteman
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Passive Radiator

Unread post by Latteman »

If you are using a passive radiator in a speaker design would u consider it as having a character- an effect on the overall sound. Would a ‘vintage’ driver converted to run passive give a different sound to a ‘modern’ driver ?
I am accidentally running a driver in my speaker as a passive radiator and have modified accordingly.
I have some ‘69 Richard Allan drivers that I could consider which actively have character but would that be carried over passively
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karatestu
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Re: Passive Radiator

Unread post by karatestu »

Latteman wrote: Mon Dec 27, 2021 10:23 pm If you are using a passive radiator in a speaker design would u consider it as having a character- an effect on the overall sound. Would a ‘vintage’ driver converted to run passive give a different sound to a ‘modern’ driver ?
I am accidentally running a driver in my speaker as a passive radiator and have modified accordingly.
I have some ‘69 Richard Allan drivers that I could consider which actively have character but would that be carried over passively
Cheers
I don't know exactly Peter. I expect that it won't be as important as the passive is only producing a very limited range of bass depending on the resonant frequency of the driver and how you have tuned the box etc. To do it properly it's just like designing a ported speaker - the passive's output is usually used to fill in where the active driver s rolling off hence making the response go deeper.

Passives usually have very heavy cones to lower the Fs and enable them to go low. When I tried it I had alot of blutack stuck on each driver . They made a useful contribution down low but I doubt I had it set up optimally and it sounded slow compared to sealed box.
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Re: Passive Radiator

Unread post by Latteman »

karatestu wrote: Tue Dec 28, 2021 9:07 am

Passives usually have very heavy cones to lower the Fs and enable them to go low. When I tried it I had alot of blutack stuck on each driver . They made a useful contribution down low but I doubt I had it set up optimally and it sounded slow compared to sealed box.
I’ve made the cone heavier and ‘shorted’ the voice coil with a resistor from information doing an internet search.
It’s an interesting evolution of my speakers and has stayed unchanged for longer than anything else 😂
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karatestu (Tue Dec 28, 2021 3:31 pm)
Analogue Source -
Denon DP47f- Ortofon mc20 supreme
Ifi Zen Phono
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Akai 4000DS mk2 R2R
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Amplification Nva 30vdc mono blocks
Speakers Lii Audio F-15 in Open Baffle; Ls6
Weiduka AC8.8- for digital sources
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Re: Passive Radiator

Unread post by karatestu »

Latteman wrote: Tue Dec 28, 2021 2:29 pm
karatestu wrote: Tue Dec 28, 2021 9:07 am

Passives usually have very heavy cones to lower the Fs and enable them to go low. When I tried it I had alot of blutack stuck on each driver . They made a useful contribution down low but I doubt I had it set up optimally and it sounded slow compared to sealed box.
I’ve made the cone heavier and ‘shorted’ the voice coil with a resistor from information doing an internet search.
It’s an interesting evolution of my speakers and has stayed unchanged for longer than anything else 😂
Image
You've been busy there Peter, PR's and diffusers. Hope you're having lots of fun trying these things out and enjoying the results.
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Re: Passive Radiator

Unread post by Latteman »

Most definitely
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karatestu (Wed Dec 29, 2021 1:01 pm)
Analogue Source -
Denon DP47f- Ortofon mc20 supreme
Ifi Zen Phono
Doug Self balanced Pre amp
Akai 4000DS mk2 R2R
Digital Sources- IfI stream, Ifi Neo idsd Dac; Tidal / Radio Paradise
Amplification Nva 30vdc mono blocks
Speakers Lii Audio F-15 in Open Baffle; Ls6
Weiduka AC8.8- for digital sources
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Re: Passive Radiator

Unread post by karatestu »

Latteman wrote: Tue Dec 28, 2021 3:36 pm Most definitely
Do you find the bass a bit ponderous with passive radiator ? I did but you might be more lucky.
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Re: Passive Radiator

Unread post by Latteman »

Interesting question- I do serious listening(😂😂) on records- both my turntables have diy elements- I was listening with a Wood bodied Grado and found myself thinking- slow almost pondering- not used this cart much, it’s sapphire cantilever and FL tip- changed to an Ortofon Vito Mc - much improved- no pondering- just tight n lively (oooer missus)
The Ortofon has the body removed so is naked
On the digital side the sound is again tight lively .
Overall fantastic- u must listen one day
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karatestu (Wed Dec 29, 2021 3:01 pm)
Analogue Source -
Denon DP47f- Ortofon mc20 supreme
Ifi Zen Phono
Doug Self balanced Pre amp
Akai 4000DS mk2 R2R
Digital Sources- IfI stream, Ifi Neo idsd Dac; Tidal / Radio Paradise
Amplification Nva 30vdc mono blocks
Speakers Lii Audio F-15 in Open Baffle; Ls6
Weiduka AC8.8- for digital sources
Mini BMU for analog sources

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karatestu
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Re: Passive Radiator

Unread post by karatestu »

Dear Peter,

It is very pleasing to hear of somebody's diy bringing them so much enjoyment. I would be very interested to hear them and the rest of your system. Give it a little while so this covid wave can subside and I would be happy to accept an invitation.

Regards, Stu
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Latteman (Thu Dec 30, 2021 9:53 am)
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