seas h955 has anyone used this?

[scooby1]

acoustic concepts has these on special at the moment. Just wondering if anyone has used with success.? cant find anything on encolsure size anyware. thanks

[MethMan]

May be it has similar problem as L18

Production has been terminated after one year. Substitution L22

[scooby1]

Cheers Methman.... gee that Zaph works hard !! i think i still might have a look. perhaps some careful placement of felt or some other damping.. mass loading stuck to cone will help with break up??? or just use low crossover..

[MethMan]

Damp it? Few problems come to mind:
1) Hard to find where cone breaks. With stroboscope?
2) On which freqencies? It could be visible in impedance measurement as small peaks.
3) Which ones are those you seek?
4) Finally if you find a damp them new problems will probably, suspiciously surely, rise.
5) Repeat steps 1)-4) to remove unwanted consequences :-(
Mass loading on cone is the same as above plus some other problems.

In my opinion lower, steeper crossover and a way better - notch with adequate Q - is possible solution.

[tktran]

According to SEAS, the recommended cabinet is 24-22 litres, in a sealed box:

http://web.archive.org/web/200312111...ne+line+up.htm

IMHO it should make a nice woofer for a 3 way, crossed low (300-400Hz) using steep filter eg. acoustic LR4. You may be able to get away without a notch filter, but if you use first or second order filters it will definitely be necessary...

[scooby1]

Thanks TKTRAN, 3 way is not really what im looking for at the moment, but i was wonder ing if i would get away with crossing over at around 1.3k 2nd order to seas 27TDFC. I assume i would miss out on any hearable distortion eg nasty peak is at 5k. 3rd harm 3.9-4k so should be alright ?? or am i wrong i am a novice who is learning through reading all you guys posts... you have some great speakers tktran very professional looking!
METHMAN. Ah yes i think i was having a little dream RE. damping etc
i dont have any measerment equip or the like to test result. so would no doubt encounter more probs. thanks for bringing me back to reality
thanks alot guys...is great to get feedback any more advice would be greatly appreciated.



I'M NOT VERI SMART BUTT I CAN WIFT HEVI FINGS..!!

[tktran]

Thanks for the compliments. My gallery is supposed to be a working diary to help myself and other builders, but somehow I always forget some steps (eg. missing pictures of crossover placement, port location etc)

I think 1.3Khz is too low for the TDFC. You could do it but there would be plenty of distortion from the tweeter. I think the TDFC is best suited around 2Khz.

[MethMan]

Look at SPLmax1.xls at LinkwitzLab page
27TDFC with Xmax=0.25 mm can give you ideally max SPL 104 dB at 1m at 1.3 kHz (92dB with Xmax +6dB from woofer contribution +6dB from baffle, if sufficiently wide). 20 dB+ overhead for peaks is recomended. IMO sufficient in small room or moderate level. I've used 27TFFC (should be very similar) with xo at 1.7 kHz and at loud levels, even if in small room, sounded little bit "warm" to me. I don't want you discourage you in any case, only take those things into account.

I assume i would miss out on any hearable distortion eg nasty peak is at 5k. 3rd harm 3.9-4k so should be alright ??

With 2nd order xo at 1.3k and 15dB peaks from 4.5k up? I don't think so. (btw. octaves 1.3k-2.6k-5.2k-10.4k) TKTRAN is true, 3way is the way.

[scooby1]

3 way it is then ..400hz crossed to peerless nomex 6.5 830378 and above 2.5k seas TDFC.
i want to make six of these babys. Does anyone know where i could farm out crossover building to?
mmmmm i think the idea of sweet nomex mid should mix well with snap of metal sealed bass ?