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.🙂
Attachments
All I have to say is.. ohh no... 🙁 First off, you spent more on the boxes than the drivers!!! Second, why couldn't you have done an isobaric setup?? half the box sizes.. 😛 lol... you go try that now and tell me how it sounds.. 😀
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:
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.. 🙄
Yeah, I know. But I actually wanted boxes that size for furniture reasons too. Besides, with 2 speakers per box in parallel would have been with 4 ohms. No go. I did actually consider many options including 6th order bandpass. I was going to call it the Badass Bandpass.
Why is 4 ohms a no go?? 🙂 also, did you consider 10inch rather that 8inch? Like the Jaycar Paper Cone 10inches rated at a WHOPPING 40watt RMS.. 🙂 lol.. My brother wants some CHEAP, SMALL speakers for his room.... I wonder what wonders can be performed.. lol.. 🙂
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:
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.
Yep. If *their* specs are accurate they are not good enough to say the least.
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.
BTW, Jaycar measures its own parameters after a minumum of 15hours of break in time... perhaps you did not do this?
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.
Not ReSponse, just cheap "Jaycar" brand ones... I think.. they do not go by the brand name "ReSponse" but they could be made by the same people.. 😛 maybe.. lol
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))
- Status
- Not open for further replies.