Ribbon Computer Speaker Idea

[Arctophile]

Hi All,

The place where I work here in Oz has just received a shipment of surplus Foster ribbon tweeters - here's a pic:


My idea for them is to build small computer speakers with 5" mid-woofers, but the recommended xo freq for these silly little things is 6kHz. Here are the specs: http://www.allenorgan.com/forsale/fo...hFacePlate.pdf
No Fs is given, but such a high xo would really limit my choice of midrange wouldn't it....

If I were to use a Peerless 850489 5" (HDS with phase plug, disco'ed) per side, how high a xo point do you think I could get away with?

http://www.wagner.net.au/pae/Data/Peerless/850489.pdf

Another possibility I was considering was a 2" dome midrange (we have some which are a copy of an old Dynaudio design - see: http://www.jaycar.com.au/productView...M2092&CATID=15) and a 5" woofer such as this: http://www.jaycar.com.au/productView...W2100&CATID=15.

Any recommendations, with the proviso that I'd like to keep the whole project under AU$200?

TIA,

//Adam F

PS I know about the "head in a vice" issue, and that's fine as I don't move much at my desk

[ThomasW]

I have a couple dozen of a similar model. They're really a supertweeter, and not a particularly good one from a sound quality standpoint.

XO point should be 6.5kHz or higher.

The 2" dome will probably be beaming if you use a high enough XO point that's safe for the Foster.

My advise, is forget about using the Foster and design a project using a good dome tweeter.

[AndrewM]

I always had an idea in the back of my mind of designing a PC speaker system using a B&G NEO 8 along with some type of woofer, or maybe a NEO 8 and stack a couple of 5" woofers on the side. Really wouldn't make for a compact speaker setup though. I have an old set of Monsoon's on my desk now, and the planar side sounds wonderful, the 5" monster sub leaves a little to be desired. And now the amp setup is having issues, so I may have to put the above into action soon.

[JonMarsh]

The Foster will want a crossover point around 6-7 kHz.

The dispersion of the Peerless Midwoofer suffers much above 3 kHz. You could make an excellent budget two way with a simple crossover and the Peerless, using something like the Seas H1212, crossed over around 2-2.5 kHz. The crossover for a three way gets rather complex, rather quickly, just sheer component count, so considering your budget, I wouldn't recommend that approach.

Just a simple question- is your goal the best small speaker you can build for AU $200, or using parts from where you work? I guess another question is whether the Seas tweeters are available in OZ. They're pretty inexpensive here.

~Jon

[Arctophile]

Thanks for the tips guys.

I really wanted to do a cheap ribbon experiment with drivers from where I work.

With that in mind, I picked up today a couple of Vifa Logic BC14WG49-08 5" mids (the best 5" we have sadly), a couple of the ribbon tweeters, and enough xover components to make 2nd order or 4th order slopes. Total outlay somewhere in the region of AU$50 (prices for staff only sorry aussie readers!).

A colleague tells me he's been experimenting with them and reckons 5kHz with a steep slope should be OK. He probably hasn't had as much exp with them as you have though. Obviously running the 5" up to 5k is far from ideal, but I think it might be acceptable for the cost.

There was a nice 4" paper cone driver available, but I decided against it since its Fs was over 100Hz and I'd like to be able to use these speakers by themselves at the computer (near field use only).

If you think the plan's a total loss I guess I'll just get some cheap dome tweeters to match the Logics. Seas H212 are about AU$70, I was planning to get some H1189s (about $60ea) for my dipole project but I'd consider them too good for this project, which is now has a "challenging" budget of $100 :B


//Adam F

[Pancakes]

For a setup on a budget you might just find that more than one component won't run up that high anyway so these speakers and their high frequency capabilities are a waste of your limited budget. If it's for a PC (Gaming?) whats the point? Use a small Piezo horn and a shielded 4' mid so you don't poke your monitor, add a vented isobarik 6" sub which will allow a high XO. There's a PC setup.

[ThomasW]

Somehow I doubt the OP is still following this 2 yr old thread...