The DD-15 is still a great sub. I own two. I recently repaired one of mine myself. I ended up having to replace the amp which costs around $370.00 from Velodyne in Germany plus about $180.00 for shipping. I had replaced all of the caps on the main board but it didn’t fix the problem.
The DD-15 was $5000.00 new and still competes with the best available. REL is not a real sub IMO. They don't even go down to 20hz.
You can’t just replace the plate amp with an off the shelf version as someone suggested. The Velodyne amp is 1350 watts plus eq and much more is involved.
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