• The swap meet forum is for private non-commercial transactions. Only unmoderated members can post here.

    diyAudio provides this forum for the convenience of our members, but makes no warranty nor assumes any responsibility. We do not vet any members. Use of this facility is at your own risk. Customers can post any issues in those threads as long as it is done in a civil manner. All diyAudio rules about conduct apply and will be enforced.

For Sale German Physiks - 4 DDD drivers

Things you have for sale.
Sorry, unfortunately no T/S data; I'm not aware of any place where German Physiks would have published them. Also, given that a DDD driver moves through four different modes of operation throughout the frequency range, T/S data may be of limited use (see interesting writeup here: https://www.german-physiks.com/technology-ddd-driver-development).

What I do know is that output below 100Hz is limited, so in their speaker designs, for main speakers they start rolling off at around 200 Hz and then integrate with some version of regular drivers and box design depending on how much bass output is required. The exception would be the in the aptly named Unicorn, which is a single DDD driver horn design reaching down to 40 Hz.
 
  • Like
Reactions: deanznz
Certainly, and since German Physiks aren't sharing, building an enclosure for these will require either some trial and error, or an own capability to measure T/S parameters.

I've used 10L boxes for these and achieved what I think is great surround speaker performance, but other implementations would have to find their own way toward success.
 
These drivers are unusual, the cone doesn't move as in a traditional cone speaker but the signal 'ripples' down from the voice coil to the surround.
It's a bending mode driver, radiating sideways. So T/S is not relevant here.
That also means that the 'cosmetic blemish' is a functional blemish, although effect will be minimal.

Jan
 
You're absolutely right; given how they operate technically, it is a functional blemish. Since I haven't been able to detect any impact when measuring the speakers I'm inclined to write it off as cosmetic, but of course, someone with better equipment and skills might be able to pick something up.