Levitation TM




Designer: J Brewski

Project Time: 20+ hours
Project Complexity: Novice
Project Cost: $100-$500

Driver Selection
The Fountek FW168’s selection was based on experience with the driver during the ruination project. The woofers were well received in the ruinations and this was a chance to try out a different tweeter paired with the driver. The Vifa BC25SG15 was selected because I had them on hand from another speaker, the buyout version had been liked by Lou C and JohnnyRichards on the forums, and the measurements could be obtained from zaphaudio.

Enclosure Design
I bought a Yamaha bookshelf speaker that was 8” wide, by 12” tall, and 9 5/8” deep. I then bought cherry boards to use as baffles. I flush cut the cherry boards to the front of the speakers to make baffles for the bookshelf speakers. I then cutout portions of the original speakers baffle away to make room for the drivers in the new baffle. Because portions of the speaker cabinet were more thin than I’d expected braces were added from side to side and front to back. The entire cabinet was then lined with sonic barrier in an effort to fight cabinet resonances. My version of the Levitations ends up being 10L with a 1 5/8” diameter port that’s 4” long which gives the speaker a modeled f3 of 54 Hz. I’ve designed a larger version of the Levitations that was built by Burgmike and information on those can be found in the levitation TM’s completed thread. http://techtalk.parts-express.com/showthread.php?t=224505

Amplifier/Crossover Configuration
The vifa tweeter’s slope is 4th order bessel crossed at 1700 Hz because I’m crossing the tweeter fairly low I decided to add an LCR to the tweeter as a precaution to make sure I wasn’t over stressing the tweeter too much. The woofer’s slope is 3rd order 1300 Hz. The speaker has a wide BBC dip that starts at 600 Hz and ends at 6000Hz.

Conclusion
They’re a better speaker than I’d anticipated and could easily be used as mains as well as surrounds. With slight modifications to the crossover a variant of the speaker has been made to be used as a center channel. My wife loves the cherry baffles and my daughter likes to dance to them when I occasionally hook them up as mains. The total driver cost is ~$120.00 and expected total cost for the project would be ~$250.00 Feedback on the sound from MWAF was: Fairly big sound from a little box, Good depth and imaging, Nice balance. Vocals were very nice, Pretty good bass for a little speaker, Seemed a little bright on the top end. Nice sound, sounds bigger than they are, Very good. Feedback from PE forum members: “I will say they are devastating for very short money. Musical, with great dynamic impact and strong overall bass even if it does miss the bottom octave. I did expect them to be a bedroom speaker, or at least a kids room, but it is a dang shame they are sitting as surrounds. They meet my 10x rule and would hang with anything $1500-$2000 in the 6″ bookshelf world.” – Mike Z “I love the speakers! The detail and presence they have is beyond anything I thought I would get for the money. The Vifa tweeters are amazing! I’m going to beg for a cc scheme from Brewski when I get back in the country to finish my front stage. I highly recommend this build!!” – Burgmike Many thanks go out to Wolf and Mike Zisserson for their help during this project.

About The Designer
I’m in my late thirties testing medical devices and the software on them for a career. I’m relatively new to the DIY speaker hobby and have only been building speakers for a couple of years now. My wife and I have been married for four years and she’s been very supportive of my hobbies. My daughter will be turning two shortly and manages to keep my wife and I fairly busy.

+ There are no comments

Add yours