I know this has been on here before but I am at a point that I need some help.
I have drawn the SF Extremas in AutoCAD using photos I scaled from known dimensions to get the general shape as close to the original as possible. I have sourced a set of KEF B139 for the passive radiators and a set of Chinese cloned Dynaudio tweeters.
The cabinet will be a laminate of 3/4" MDF with hardwood sides. I have had the templates cut from 5/16" aluminum plate which will allow me to cut the general shape of each laminate piece and then use a flush bit on my router to get them to the exact shape. Each template has 1/4" locating holes to be drilled and fitted with 1" dowels. The front plate that will eventually be wrapped in leather gives me the freedom to try different drivers. The calculated internal volume is 20 liters, just like the original.
Where I need help is the woofer selection. There are so many to choose from it is a bit overwhelming.
Thank you in advance
Dean
I have drawn the SF Extremas in AutoCAD using photos I scaled from known dimensions to get the general shape as close to the original as possible. I have sourced a set of KEF B139 for the passive radiators and a set of Chinese cloned Dynaudio tweeters.
The cabinet will be a laminate of 3/4" MDF with hardwood sides. I have had the templates cut from 5/16" aluminum plate which will allow me to cut the general shape of each laminate piece and then use a flush bit on my router to get them to the exact shape. Each template has 1/4" locating holes to be drilled and fitted with 1" dowels. The front plate that will eventually be wrapped in leather gives me the freedom to try different drivers. The calculated internal volume is 20 liters, just like the original.
Where I need help is the woofer selection. There are so many to choose from it is a bit overwhelming.
Thank you in advance
Dean
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This is just one example. Nowadays tweeters are delicate devices, i don't think it's worth to buy a cheap chinese clone if sound quality is priority.
Depending on the shape of those old passive radiators you got, you might also consider the se SB radiators: SB Acoustics SB15SFCR-00 5x8 Passive Radiator
I already have the KEF B139 woofers and the clone Dynaudio tweeters.
I found a set of the B139 woofers in excellent condition.
Really interested in thie project. I was trying to do it some tiem ago and I left because the big difficult on the wood shape.
Original SF Extremas use the Skaaning midwoofer, closest available now are from Audio technology. You can contact them to customize a pair closest to the original Extremas.
It seemed to me that those early Sonus Faber speakers are the hardest thing to clone, and I ended up buying original SF Minima from Germany. I sold them to my friend later, but Minima is one of a very few speakers that I still regret to part with, and Extrema should be even better.
Good luck!
Good luck!
Being that it was/is a laminated cabinet I made the aluminum templates so that most people with a router and a power saw could make them, the only thing that I have that most people do not have is a small CNC that I will be able to use for the faceplate. I will hopefully be able to make the templates available if the cabinet turns out as I hope.
What spurred me into this project was a pair of Sonus Faber Electa Amator II's. I found a set for a great price and waited too long to move on them and missed my chance. I have always lowed Sonus Faber, and have owned several sets, heck, I still use a set of SF Concertinos to test old audio equipment.
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edit: in respect to choosing a driver for the Extrema, fancy a Dynaudio/Audio Technology sort of a knock-off driver,Dynavox LW 6004 PMR-N, 50 bucks/piece at PE?. It seems to have a higher inductance value which might work in your favor this being an inductorless midwoofer crossover design. There is a tweeter clone also, Dayton Audio DC 28F-8 for 20 bucks.
manage attachments
browse
upload
preview post
edit: in respect to choosing a driver for the Extrema, fancy a Dynaudio/Audio Technology sort of a knock-off driver,Dynavox LW 6004 PMR-N, 50 bucks/piece at PE?. It seems to have a higher inductance value which might work in your favor this being an inductorless midwoofer crossover design. There is a tweeter clone also, Dayton Audio DC 28F-8 for 20 bucks.
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