DIY Project - Infinity Kappa Tribute

[Mudjock]

I don't post very often on AK, but I thought this group might be interested in a recent DIY speaker project of mine. The project is named "Indium 7" and shares design cues from a number of Kappa speakers. Since it is a 3 way with 1 woofer, dome midrange and planar tweeter, it seemed more like a "7" than an "8" or "9". I am including a few links where more information can be found.

http://projectgallery.parts-express.com/speaker-projects/indium-7/
http://techtalk.parts-express.com/forum/speaker-project-gallery/1276776-indium-7
http://www.parts-express.com/ssv4_pg28_indium-7

Between the 3 links, there should be enough information for anyone interested in building them. I will check in here periodically if there are any questions.

Drivers and crossover components for this project run about $340.

It would be interesting to run these against some actual Kappas to evaluate similarities and differences.

 

[jazzmans]

They look great! I wonder how they sound myself, especially compared to any of the classic infinity speaks....

Feel free to talk details about how each driver sounded.

 

[StimpyWan]

Very nice, and a job well done! A nice write up article too. I'd love to hear them. But, I guess that'd mean building a pair. It would be fun to try!

Also, I noticed something odd with your crossover schematic. Your 3rd link, to the PE Project page, contains a schematic that appears to be mislabeled? The top driver is labeled as the Beston tweeter, but the schematic shows a series inductor (L1), with a parallel 68 uF cap (C1). So I'm guessing the labeling between the woofer and the tweeter got swapped? The schematics shown in the other 2 other links look correct.

Thanks for sharing!

 

[Mudjock]

Also, I noticed something odd with your crossover schematic. Your 3rd link, to the PE Project page, contains a schematic that appears to be mislabeled? The top driver is labeled as the Beston tweeter, but the schematic shows a series inductor (L1), with a parallel 68 uF cap (C1). So I'm guessing the labeling between the woofer and the tweeter got swapped? The schematics shown in the other 2 other links look correct.

That is a good catch. The crossover in the first two links is correct, while the woofer and tweeter are swapped in the lower link.

 

[StimpyWan]

Sorry. I'm a bit anal about details. Too many years spent doing QC work, I suppose!

Also, I definitely want to hear more of your input on their sound quality. Especially in comparison to the Infinity's that you've heard and owned. Plus, I can't argue against your using the Kappa series as inspiration. They were very balanced and relaxed speakers. Easy to listen to for hours without fatigue, even though they had good detail and dynamics.

 

[Mudjock]

Feel free to talk details about how each driver sounded.

My biggest concern with this project was how the 10" DVC subwoofer would sound playing up to 700 Hz. A lot of people who heard this at an Indiana DIY speaker gathering were surprised by the quantity and quality of bass given that the woofer was in a sealed enclosure. I find the bass to be tight and articulate. The HiVi dome mid has a slightly smooth and warm character, which blends well with the character of the woofer's response. The Beston round planar is fast and detailed, but is loaded into a shallow waveguide, so it's response drops a little more off axis. I would describe it more as delicate than bright.

Overall, this is a speaker that isn't ruthlessly revealing, but is well balanced and non fatiguing even with recordings that are not the best. The drivers are still capable of resolving detail and competing with considerably more expensive speakers.