'JASD' (Just A simple Dipolspeaker)

[nobistar]

Hi,

my name is Norbert, I'am from Germany, so please forgive me my terrible englisch . Month ago I started reading in here and today I will present the 'JASD' (Just A simple Dipolspeaker).

2 years ago I started with this glasswall und a SALABERT PHY21 which is well known (I think) in this forum. The dipol itself has a flat frequenz response up from 80Hz wenn it is positioned 40-50cm from the backwall of the listening room.

I had 2 problems with the PHY. First, in the high frequency range from approx. 9-10khz the curve is falling down (that means: using a supertweeter) and second: there is a need for an additional subwoofer. But my wish was/is running a fullrange system (55-16000Hz) with only 1 unit.

Weeks ago I found an italien manufactored driver the 'CIARE CH250' http://www.ciare.com/pdf/catalogo/CH250.pdf
which has an Qts=1.36 at 65Hz und this dip fills the hole at 50-80Hz.

Not only in relation of the price (app. 42.00 US$) its sounds wonderfull and I have a lot of fun with this dipole.

[Nuuk]

Hi Norbert, that's a very nice speaker that you have there and let me say straight away that I am a big fan of keeping things as simple as possible.

I am currently using modified Goodmans 201's full-range drivers in open baffles (with piezo super-tweeters) but am looking for something more in the 40-90Hz region. Those Ciare drivers seem like a dream -come-true!

Do you find that you don't need a supertweeter with the Ciare drivers?

[qi]

Great idea and very striking!

Does the glass ever "ring" or is it acoustically dead?

[nobistar]

@NuuK

Do you find that you don't need a supertweeter with the Ciare drivers?

Don't need them because my ears clipping at 14kHz...
I tried an additional FT17H at 11kHz but for me it's ok without it.



@qi

Does the glass ever "ring" or is it acoustically dead?

Thick of the glass ist 8mm (1/3 inch) and weight is 12.5kg, so in combination with the screwd 18mm wooden plate it's absolutly dead.

[Nuuk]

With the low cost of the driver, even the price of the glass baffles doesn't make this an expensive speaker. If they sound anything like mine, this has to be the best sound-per pound speaker going!

Add a Gainclone and something like a modified CD723 and you have a seriously good system for 450UKP. DIY rules.

[Bricolo]

I've been told that glass doesn't have strange resonance modes, and that it

doesn't reverb at all (or doean't reverb distorted sound)

is this true? If yes, glass could be used for open bafle loudspeakers just like here. And maybe totally made of glass, would look cool!

[Nuuk]

Well most of us have glass windows in our listening rooms! I have often wondered if it does affect the sound but with the (heavy) curtains closed at night, I cannot hear any difference.

[Bricolo]

I think I'll try some open bafles made of glass, too

I know nothing about IB design, where can I start with? Do you guys have good links?

[RHosch]

Glass panels resonante just as any other panel with sufficient stiffness will. What is nice about glass is that it has a fairly high modulus for its weight. Brittle... but stiff.

[Nuuk]

I know nothing about IB design, where can I start with?

If you want to try it Bricolo, you couldn't do any worse than try these Ciare drivers. Use a piece of ply/MDF for the baffle (brace it though) and you can see if you like it. You can see what sort of size from Norbert's picture.


Try different speaker positions etc. If you do like it (and I can't believe that you won't) just get your glass baffles.