Did anyone bought the new 18M mid and compared it to the older 18W? It does look interesting and I am considering selling my 18W to go fo the mids with a larger woofer for bass duties. Lower mms, foam suspension, shorter vc with less inductance and a titanium former, appealing to me 🙂 But, the Klippel test I saw on Audioexpress does not seem that good - pretty high distortion in the 700Hz-3Khz area, even if dominated by 2nd order. its also quite efficient and I don`t like putting resistance (even if a coil with a larger DCR) in front of about anything 😀
The 8531 has somewhat high 2nd order too compared to other good woofers. Higher order is most excellent though, a fair compromise. Around 900Hz it's because of a cone resonance. What is making the 8631's 2nd order peak again at 1.4kHz i'm not sure - perhaps changing the surround did it.
It somehow doesn`t distinguish itself much from its older brother, I fail to see much advantage of using it over the 18W.
Agreed. Comparing the data in Audioexpress' article and Zaph-Audio's measurements the 8531 looks like a better behaved driver, alas at the penalty of 2dB lower sensitivity.
Why not buy a single unit and listen to it?
After baffelstep-compensation, they are down around 84-85 dB.
Troels Gravesen writes positive about them.
They also require a much smaller cabinet. For closed box and midrange I would not use 18W8531 in a smaller box than around 25 Liters. And on top of that you need passive components to limit how much bass they play.
After baffelstep-compensation, they are down around 84-85 dB.
Troels Gravesen writes positive about them.
They also require a much smaller cabinet. For closed box and midrange I would not use 18W8531 in a smaller box than around 25 Liters. And on top of that you need passive components to limit how much bass they play.
Why? The 18W/8531 only wants a 21L sealed box for Q=.707 response. Shrinking it to 10Litre box it is barely 1dB away from that.
The 18M/8631 is ironically far less tolerant of small boxes because it has a higher Qts. Stuffing it into a 10Litre box results in a response that peaks up twice as high as the 18W/8531.
Both need a highpass filter to be used as a midrange, granted that the components needed for the 8531 will probably be slightly larger for a given XO frequency.
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Dont know what happened to my simulations. Yes around 21L sealed box for Q=0.707 response.
Listening test will tell if it actually sounds good in a small cabinet ca 10 liters. I think not - I think it will sound better in a bigger cabinet.
Listening test will tell if it actually sounds good in a small cabinet ca 10 liters. I think not - I think it will sound better in a bigger cabinet.
The 18M needs a largish enclosure compared to the 18W, in something like 10-12l it peaks. Besides, I cannot buy a signle unit - these are sold in matched pairs. The cone looks the same as on the 01 version.
Yes, I did. And as I can remember 18M certainly a bit better than 18W when using as a true midrange.
I will publish my measurements at my website
hificompass.com
by the end of June and you can see that.
Regards,
Yevgeniy
That looks exceptionally good. Distortion seems to raise only slightly when driven with higher voltage and if crossed at around 300hz-1.9Khz can be a really interesting driver. The spike of 2nd order distortion is narrow unlike the one on the 18W sibling which is wider, overall a very cool unit.
Thanks a lot again for posting these.
Thanks a lot again for posting these.
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