diyAudio (
-   Planars & Exotics (
-   -   ribbon mid and woofer (

biovizier 1st October 2006 10:42 PM

ribbon mid and woofer

I am thinking of putting together a full range ribbon design if it is possible. Tweeters like RAAL look pretty good but only go down to 1 khz or so - does anybody make a mid ribbon that goes down a bit further? To where it could be crossed with a sub? Ideally a ribbon woofer would be great but such a thing seems not to exist bar the full range apogees and the like. Does anything exist in pro audio?



moray james 1st October 2006 11:32 PM

have a look...
I have come across planar magnetic midrange designs but I am sorry to say I cannot remember where or who. You can look at this speaker design as it sounds like it might be what you are looking for.
Beyma have line source wave guides for compression drivers that will run from 700 Hz up to 20 KHz. at about 108 db I think.
You might also consider buying a bunch of inexpensive mid/tweeter planar drivers and run them as a line source and that would allow you to run them lower. Remember that a 10 inch bass/mid can be run up to 800 Hz before it gets too directional and a 6oo Hz xover would be a good choice so you dont need to run your planars down all that much further to meet the bass/mid. If they were cheap enough you could run a vertical aray two units wide in a line as mids and that would give you lots of output.
You might also consider building a planar mid yourself. Use 30 gage magnetic wire (or lighter) on a mylar diaphragm (you could consider a thin foil under layer to wick heat). A simple line source magnet made of ceramic magnets or neo with a couple of 1/16 inch thick pole plates if you want more output. I have built this kind of driver and they work very well. Remember all the turns of the vertical vioce coil have to go in the same direction so if you start at wire no 1 and go up you will need to come off the diaphragm to a harness and go back down to the bottom for coil wire no 2 and so on. You should be able to get to about a four ohm load in a four foot length with the right choice of VC wire dia.. Good luck regards Moray James.
PS: you might also want to take a look at some of the available mid/tweeter planar units on the market to see if the back assembly could be physically removed so they could be run as a dipole. This will sound better and will also stage and image better and probably allow you to run the diaphragm lower in frequency especially if you run multiple units.

Ben_Tech 2nd October 2006 07:49 PM

I have a pair of Eminent Technology (ET) LFT-VIII's that have a midrange planar-magnetic driver that goes down to around 100hz. Really nice speaker. You could look for a used pair or contact them to see if they would sell you the midrange panels as 'replacement parts', etc. I know the magnetic fields on these things are really strong, so you need to be careful when disassembling or tinkering with them.

Also, Bohlender-Graebener offers the RD series which may go as low as 150hz, but for that kind of money, just save some coin and buy a pre-built pair of ET speakers, imho. They are excellent. :)

biovizier 2nd October 2006 09:45 PM

Yup thats what I was planning to do - create a line array of tweeters and mids to get better SPL and lower end frequency. I had considered operating as a dipole.

The two raal units ( cover from 500 hz and 2 khz, though I guess I would have to crossover above 500 as the ribbon might not be so well behaved there.

So I was really looking for a midrange ribbon to to cover say 150 hz to 600 hz or so. Below that I hoped a ribbon subwoofer might exist - maybe in the pro arena - or use a conventional subwoofer like mj acoustics or velodyne.

Maybe I can use the ET ribbon - they might sell me a couple of pairs to get the required SPL levels.

biovizier 2nd October 2006 09:59 PM

These guys seem to make mids that go from 100 hz to 16 khz - I could cross that with the higher frequency RAAL unit at a few khz. Maybe run the sub up to 200 hz or so...

Is there any ribbon commercially available that can handle 20-200?

moray james 2nd October 2006 10:02 PM

check these sites...

biovizier 2nd October 2006 10:08 PM


Also the new bg neo10 goes to 150 hz...

el`Ol 6th October 2006 11:42 AM

And here is the magnetostatic subwoofer:

biovizier 6th October 2006 12:09 PM

Dont their subwoofers use 12 - 18 " conventional drivers? The mad array only goes down to 50 hz -3db point according to the faq.

el`Ol 6th October 2006 12:57 PM

You are right, their dipole woofer is equiped with conventional drivers now. I believe to have read about a planar woofer some time ago, but I am not absolutely sure.

All times are GMT. The time now is 08:30 PM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 18.75%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio