Project for next summer. Help needed.
 

Hey,

I just finished Cyburg's needles few months ago and I have already next project on my mind. I think I would like another fullrange or maybe FAST. I would like the speakers to go little lower and maybe have little more "oomph" in the bass region than needles. I would like to make as small as possible bookshelf speakers. They would initially go to bedroom but if they are very good I might replace needles with them.
I guess in small enclosure I wouldn't get fullranges to go very low so FAST would be better. But because of WAF I have to get very small amplifier and even bi-amping is probably out of question. I have to admit that I also like small T-amps more than bigger amps :). So could FAST with passive crossover and a TA2020 amp be possible or should I look into more traditional two-ways? For example from fullranges CSS el70 seems interesting.
There are also other limiting factors:
-I would like to keep the price for electrical parts under 200e for pair. Little over might be possible but depends very much on what kind of summer job I get.
-I'd like to use a dead simple cabinet design. I am planning to make then enclosure from polymer concrete (a.k.a synthetic stone, marble etc.) as it is very interesting material to someone studying material science and polymers. The easier the design the easier the mold is to make. With very simple design I could have as little seams as possible. This is also one reason why I would want small boxes as big ones would be very heavy and quite expensive.

So anyone got any ideas on what drivers I should use or even what kind of design would be the best. All help is apprieciated.

-Ossi

Ossi - it probably won't take long for posters here to suggest a bewildering array of recommended driver configurations and enclosure designs to fit within your criteria ( I definitely have some favorites of my own - and even those vary over time or with the application)


It's certainly possible to create very interesting enclosure shapes with cast polymer / resin based synthetic stone materials, but for sonic reasons, I'd strongly suggest you include the option of more conventional materials (ie, plywood, particle board or even solid woods).

Terve!

I have the Mar-Kel70 and i'm really happy with them. They deliver quite good "oomph" in the bass despite its small size. It's a really good 4" driver producing such bass.

You can buy the drivers from Hifitalo.fi for €49 each, a real bargain!

Onnea (i think that's right)

Hej,

You got that finnish right, Rullknufs! I was looking at those from hifitalo. Bought parts for my needle from there so I know the store.

Chris, One of the points was to see how those resin based materials would work and it would also make a interesting look (I'll use PC for polymer concrete from now on.). But would it be sonicwise better if it had PC layer on outside and wooden inner walls? I could use the inner mold piece that I need as part of the finished enclosure. That way I can probably keep wood and PC walls thinner. Can you clarify more about the sonic issues with PC? They aren't really my forte :). Using just PC would be the ideal case as I want to learn but I am willing to compromise for the sake of better speakers. On the other hand using just wood isn't something I want to do this time.
The good thing is that I have some time before I can to start to work so a lot of suggestions would make me happy.

Sealed would be easiest to approach... The CHR70 in 5-7 litre is the 1st thot. Giving up a bit of LF extension for an extra 4dB by using EL70 would make the T-amp happier.

Attached are the standard sealed sims, and a 6 litre vented. For the latter mount the vent externally and use it as part of the stand. Some sort of organic shape would be doable with this material... might i suggest something like the FujiTens?

dave

Sorry Dave but my girlfriend won't approve those mighty fine looking Fujitens :D. I would have made those ikea bowl speakers but she didn't like those either. So it has to be somewhat traditional looking. But who knows maybe she lets me do something different looking if it is stilll "cute" enough ^^.