First off, the idea of this project was to see just what I could get out of a dirt cheap driver. Jaycar has an 8 inch 30 watt paper cone woofer for ~AUD$30 http://www1.jaycar.com.au/productVi...&pageNumber=&priceMin=&priceMax=&SUBCATID=383 and on paper it looked just what I wanted. The T/S parameters looked good too, so I went and got a pair. Got then home and measure the parameters and they were just way off! e.g. resonance was 60Hz, not 39. Soooo..... rather than take them back I got to work WinISD Pro and looked at the effect of adding mass to the cone. I ended up (temporarily) sticking six 10 cent pieces there = 0.6 ounces total and it got the resonance down to 35.9 Hz. The boxes are tuned to 33Hz and down there they really hammer. External dimensions are 500 x 500 x 1200mm. It's just amazing what you can get out of a little speaker if you give it half a chance. Soon I will do some in-room measurements. I am going to end up biamping for sure. The whole cost was speakers $30 each, Wood 18mm MDF $78 including cutting, second hand carpet for lining, 128 screws = $8. Cheap as dirt. Top fun.
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Many apologies, your Royal Expertness. Next time I shall try not to have fun or learn new things or enjoy myself. Instead, I shall first consult you for advice; you that has obviously done more diy projects than I have had hot dinners.
BTW, where were you when I was making my first homespun engine management computer in 1986? In nappies (diapers) I believe.
BTW, where were you when I was making my first homespun engine management computer in 1986? In nappies (diapers) I believe.
Circlotron said:BTW, where were you when I was making my first homespun engine management computer in 1986? In nappies (diapers) I believe.
I am not at liberty to say..... But you could have spent twice that on the drivers, and half that on the MDF..... Would cost the same and be smaller... thats all..
Nah, just silicone sealer like you would put around the edge of a window or something. I did try superglue but it would not stick. The coin mass I said before was incorrect. It is a total of 6x 0.2 ounces, not 0.1 .LaMa said:Which type of glue did you use to mount the coins? Is het hotglue?
3.5 amps in my class A amp output choke will swing 8 ohms down to (-3.5x8) volts, 28 volt rail pulls up by same amount. Would be assymetrical with 4 ohms.Why is 4 ohms a no go??
Yep. If *their* specs are accurate they are not good enough to say the least.also, did you consider 10inch rather that 8inch? Like the Jaycar Pap
I have very limited experience in T/S parameters but to me it makes sense that the resonance freq could change quite a lot after break-in as I would expect that a stiff surround goves a higher Fs and when it softens it lowers the Fs. From this I would try to break the unit in and measure then giving me a better value to work with or work with the specs. Did you think about this?
Sweet.
Sweet.
Would It Sound Better With Dollar Coins ?
Graham, those WES specs are measured by 'Stones Sound Studio' I believe.
It may be that he is measuring them after breakin, as he does make some sonics comments, or maybe his setup is giving wrong figures ?.
Regardless, it sounds like you are getting results you like (for now).
Eric.
The top line is not entirely smart **** - when you drop a Dollar coin, it sonically rings quite differently to a 10c coin.
As to the added mass you impress,
I would try titanium and never aluminium,
and in my guesstimation,
Mallee Root would be a hoot.
Eric.
Graham, those WES specs are measured by 'Stones Sound Studio' I believe.
It may be that he is measuring them after breakin, as he does make some sonics comments, or maybe his setup is giving wrong figures ?.
Regardless, it sounds like you are getting results you like (for now).
Eric.
The top line is not entirely smart **** - when you drop a Dollar coin, it sonically rings quite differently to a 10c coin.
As to the added mass you impress,
I would try titanium and never aluminium,
and in my guesstimation,
Mallee Root would be a hoot.
Eric.
MY BROTHER WANTS SOME DIRT CHEAP SPEAKERS WITH GOOD BASS BUT ONLY NEED FAIRLY LOW VOLUME... (his room is about 3mX3mX2m) budget is whatever it costs.. So, what drivers, what size boxes.. (he wants small no bigger that 40cm high, and 25sm deep, the other measure doesn't really matter (20-30cm))
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