Hello,
I'm lurking on the Neumann KH150 or KH120 designs. I wonder if there would be around some DIY project for a similar size / performance, designed for DSP+active amplification.
I would look for good FR on and off axis, hence the waveguide (I have seen Augerpro ones). Low frequency would not be the priority, as a subwoofer would be considered. Reasonably priced: about 300-400€ max for drivers ?
I have seen the Directiva ASR R1 project, but to toy around the Purifi woofer looks way too expensive. And I like the idea that Neumann and many others achieve top performance with not so fancy drivers.
I have some experience with DSP and active amplification with my LX-Minis. But I don,t have the skills to design from ground up.
JMF
I'm lurking on the Neumann KH150 or KH120 designs. I wonder if there would be around some DIY project for a similar size / performance, designed for DSP+active amplification.
I would look for good FR on and off axis, hence the waveguide (I have seen Augerpro ones). Low frequency would not be the priority, as a subwoofer would be considered. Reasonably priced: about 300-400€ max for drivers ?
I have seen the Directiva ASR R1 project, but to toy around the Purifi woofer looks way too expensive. And I like the idea that Neumann and many others achieve top performance with not so fancy drivers.
I have some experience with DSP and active amplification with my LX-Minis. But I don,t have the skills to design from ground up.
JMF
Hi,
Augerpro's waveguide solve half your question.
Then the woofer: you've got experience with dsp? Then a 'known' ref into a sealed box with Linkwtiz Transform.
Dayton rss180 or 150 is an example.
From there, box shape to limit diffraction issues ( small bafle area and round over).
Augerpro's waveguide solve half your question.
Then the woofer: you've got experience with dsp? Then a 'known' ref into a sealed box with Linkwtiz Transform.
Dayton rss180 or 150 is an example.
From there, box shape to limit diffraction issues ( small bafle area and round over).
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Hello Krivium,
I'm along your lines. However this leaves a lot of elements to define/refine. I hoped that the above criteria could match some existing/ongoing projects, toput my steps in ;-)
JMF
I'm along your lines. However this leaves a lot of elements to define/refine. I hoped that the above criteria could match some existing/ongoing projects, toput my steps in ;-)
JMF
https://www.diyaudio.com/community/...is-and-power-response-characteristics.390242/
Well, to define/refine criteria you would have to first define your planed use.
But imho, once you have directivity matched between driver, required volume for the box and diffraction issues minimised, the remaining is most minimumphase so can be corrected/adapted by dsp means.
Well, to define/refine criteria you would have to first define your planed use.
But imho, once you have directivity matched between driver, required volume for the box and diffraction issues minimised, the remaining is most minimumphase so can be corrected/adapted by dsp means.
Also from the same designer mentioned above.
But he did not publish details about DSP settings
https://heissmann-acoustics.de/en/dxt-mon-vs-neumann-kh-120a/
But he did not publish details about DSP settings
https://heissmann-acoustics.de/en/dxt-mon-vs-neumann-kh-120a/
Thank you for all the food for thought. The posposed projects make sense to what I'm looking for. I have to digg in the threads.
The Mechano projects are well in my cost effective objective.
The Eissmann acoustics projects are also matching. It seems that the designs are not very recent however (which doesn't mean that they are not very good).
I have also just seen this one: https://www.diyaudio.com/community/...uides-for-cnc-3d-printing.318190/post-7319668
I wonder if going the DSP route from the beginning doesn't change the game a bit, by increasing the range of acceptable divers, which would be NOK for passive filters, but perfectly OK in a DSP context.
JMF
The Mechano projects are well in my cost effective objective.
The Eissmann acoustics projects are also matching. It seems that the designs are not very recent however (which doesn't mean that they are not very good).
I have also just seen this one: https://www.diyaudio.com/community/...uides-for-cnc-3d-printing.318190/post-7319668
I wonder if going the DSP route from the beginning doesn't change the game a bit, by increasing the range of acceptable divers, which would be NOK for passive filters, but perfectly OK in a DSP context.
JMF
Imho and experience yes, it was my point: once the 'acoustic design' is fixed and some details like diffraction are too, then with modern dsp you can 'taylor' almost everything to your need ( as long as it is minimal phase).
Heissman designs and explanations about diffraction are spot on imho.
What dsp do you use?
And if you choose a round waveguide, Kimmosto approach to xover ( 1,2/1,4 wavelength of xover freq for ctc of drivers) gives good results.
Heissman designs and explanations about diffraction are spot on imho.
What dsp do you use?
And if you choose a round waveguide, Kimmosto approach to xover ( 1,2/1,4 wavelength of xover freq for ctc of drivers) gives good results.
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I built a pair of amps based on the TAS3251 for my LX-Minis. The chip is a combination of Digital input / DSP / DAC / TPA3251. This is perfect to drive active speakers, with enough biquads for most of the use cases. At the moment, I play with Room correction with FIF filters, implemented in CamillaDASP on RaspberryPi.
I know how to use the tools, but I'm not a DSP expert unfortunatly.
What are the key drivers to choose between a round waveguide (like in the Heissmann design) and Augerpro eliptic ones ?
JMF
This also looks like a good candidate: https://www.audiosciencereview.com/forum/index.php?threads/revel-m105-copy-diy-build.29465/
It uses the augerpro waveguide, uses the same SB 5" woofer as the directiva r2. Lot's of measures. And some variants.
It uses the augerpro waveguide, uses the same SB 5" woofer as the directiva r2. Lot's of measures. And some variants.
Most is here: https://www.diyaudio.com/community/...controlled-integrated-dsp-amp-tas3251.325826/
Interested persons generally PM and I share the KiCAD files. There are about 10 of those running in different places. Some are just playing music at the moment driving my LX-Minis.
I have to do the homework to formally publish it as Open Source Hardware. Programming Arduino and C styles are already on Github.
JMF
Interested persons generally PM and I share the KiCAD files. There are about 10 of those running in different places. Some are just playing music at the moment driving my LX-Minis.
I have to do the homework to formally publish it as Open Source Hardware. Programming Arduino and C styles are already on Github.
JMF
The only person publishing active designs, AFAIK, is Alex Heissmann:
This is remake of MarkK ER18DXT of a decade ago.
https://heissmann-acoustics.de/dxt-mon-rnx/
This is remake of MarkK ER18DXT of a decade ago.
https://heissmann-acoustics.de/dxt-mon-rnx/