Help needed with open baffle project

[juliopr]

Hello everyone. I have been interested in DIY speakers for a long time, and made some when in High school. about 20 years later, the DIY bug is bitting me again, after seeing the Jamo R707 and 909 OB speakers. Really cool design, but way out of my reach. That made me think about a Magnepan speakers I had and I dropped only because the dynamics and bass response were limited due to the nature of the design. Now, my idea is to put 3 Eminence alpha 15 drivars in a baffle whith a BG rd40 or rd50 dipole ribbon per channel with a berhinger DQX 2496 and 6 channel power amp. Or the same 3 bass units with dynamic mids and tweeters instead of the ribbon driver. Any kind of comment, idea, criticism, mocking, joke or laugh is vary welcome. That will help me do a reality check on where am I really standing now.

Thanks.

[twest820]

If you search in the Mission Possible DIY forum at HTGuide there are several line source dipole builds using RDs or Neo3/Neo8s. See the Violet DSP evolution thread in this forum for linear phase and reasons you might want to consider a PC crossover and consider the Neo3 and Neo8 instead of dynamic tweeters and mids. See the Pt 2 Audibility of Crossovers thread in this forum for some of the same, as well as discussion of why four way is attractive for point source dipoles (and a few remarks on power amps). The Beautiful Swingin' Speaker and My open baffle dipole with Beyma TPL150 threads here are good reading as well.

I forget how low the HTGuide folks were running their RD75s, but IIRC it was a bit high for crossing to a 15 inch if you want good directionality. For an RD40 or RD50 you may end up looking at 10s or 12s. Consider Selenium drivers as well as Eminence.

[juliopr]

Thanks for your insight and excuse my ignorance... What is a pc crossover and how can I get it and hook it onto this setup? Which is the difference between the Behringer and the pc one? Also, Is not a ribbon driver more a point source than a line array? I thought line array was when multiple identical drivers were lined up to play an specific range of the spectrum.

[twest820]

The RDs are magnetostats, not ribbons. Line arrays are usually classified by radiation pattern at the typical listening distance and not by the drivers used to obtain that pattern.

A good starting point for PC crossovers is Thuneau's Frequency Allocator. Do some reading there along with the threads I mentioned and your questions should be answered.