Solved! 3 way speaker cross over

[Derekmurton]

Help please I have bookshelf speakers technics in cabinet
Super woofer 17cm
Woofer 12 cm
Tweeter 6cm dome type
Tweeter impedance 6 ohm
Woofers 8 ohm
At present they are wired from main amp 2 crossover in amp to low and high frequencies
I want to keep my speakers to use on new av amp that simply has output of 100 watts 8 ohms
So if I add a three way cross over I think I will have a nice sound but want help in selecting the correct x over.
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[americanaudiophile]

What you describe isn't the standard 3 way speaker configuration which would have a midrange rather than two different woofers and a tweeter.
You would have to check the specs for each speaker to see what crossover point and slope is recommended. Not a simple thing to do.
This might help

Homepage

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[Sonic Illusions]

What you describe isn't the standard 3 way speaker configuration which would have a midrange rather than two different woofers and a tweeter.
You would have to check the specs for each speaker to see what crossover point and slope is recommended. Not a simple thing to do.
This might help

Homepage

Resource for building, calculate and measuring Hi Fi Loudspeakers,DIY LoudspeakerSite, Acoustic treatment, loudspeaker calculations, hifi links, high end

www.mh-audio.nl

Totally agree; very unusual. To properly configure, you also need the T/S parameters and frequency curves, unless you simply want to use a generic x-over which will not give optimum results. Plus, you'd have issues because generic crossovers generally don't have multiple impedance filter sections. Be careful with the tweeter. Unless you know the spec's, you could fry it using the wrong slope at 100 watts. 12db/oct (2nd order) is common, with a sharper cut-off than a 6db/oct (1st order). You'll have to reverse the polarity. There really isn't enough info to go by. That's (roughly) a 5 inch 'woofer' which can possibly serve as a midrange and a 6.5 inch 'super-woofer.' The reason I suggest looking up the T/S (Thiele/Small) parameters and curves is because most small woofers have nasty peaks toward their upper range. Sounds like they're bi-amped with active x-overs and want to switch to the 100W amp and use passive x-overs. Is that correct? Sorry to say, a fresh set of speakers may be a better option, in order to avoid getting a headache!

 

[Derekmurton]

Thanks the woofer is being used for midrange I believe from amp so is the super woofer and the top end separatley