Sunday, March 28, 2010

Big 2 way DIY loudspeakers with waveguide

This project went from simple testing of vifa xt25 tweeter in 12in parts-express waveguide to finished loudspeaker.
I think most pictures here are self explanatory. One thing to note, this peerless SLS 830669 in it's stock form will not sound good with this crossover. It's cone starts to resonate around 700hz, and it is very audible. Cone treatments that I've applied, significantly reduced this resonance and it's audibility.

Dust caps are removed, top layer (polypropylene?) peeled from cones. Then cones are slit and coated with damping spray. Copper ring (from home depot plumbing supply) glued onto pole piece.

Red impedance curve is before and green curve is after cone treatments.

Preliminary crossover

Speaker is converted from open baffle to sealed. 12in cardboard tube ( for concrete) was glued to the baffle.

Final crossover.
I use these speakers for home theater. They can play loud with great speech intelligibility.

Until recently my main home speakers were ones with scanspeak drivers,
documented below. In process of moving I packed scanspeaks and carried out 
of the basement these speakers and placed them in place of scanspeaks.
Connected them to my favorite HarmanKardon amplifier and was surprised with much
improved dynamics over scanspeaks. Unfortunately I have to part with these speakers due to their size. In terms of sound quality, these may be the best speakers I've built, although I have not compared them directly to my 3 ways.


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  2. Really nice, a very interesting project! What kind of amps do you use? Kind regards, Carsten

  3. I use Hypex UCD180. Thanks.

  4. Ken’s other grandfather worked as a manager at the Schenectady plant of the American Locomotive Company. Smith was a life member of the Capital District Railroad Club of Schenectady. He was also a member of the Mohawk-Hudson Chapter Railway Historical Society and its parent organization, the National Railway Historical Society. Submit Articles