You can imagine NO. Magnesium is better above 200Hz. There are intrinsic physicals reason for that. The magnesium has better property stiffness/damping than aluminum. I saw this in a french physics book. I think this is why magnesium is used in audio.
I prefer a paper cone over alu cone in the midrange, it is my taste. Perhaps alu cone like the Linkwitz version or Titan version with a better motor and curviline cone improve the high midrange . I tried the L18, a lot of details but not convince by the overall sound. It is a question of taste.
If you want a lower cost magnesium driver perhaps the Linkwitz 22MG can meet your specifications.
Note the U22 could be a candidate too.
Well.... I would like to use money on quality. But 1600 Euro for 4 x 8" woofers. I think that is just way too expensive. I'm not sure will ever make sense... when even the well known drivers from Dayton, Seas, ScanSpeak, Wavecor, Morel and almost any other.... cost 1/4 to 1/2 of this price.
The 22MG actually looks very nice. But mostly looks. I simply have to little proof of improvement, to soil that kind of money - even though Linkwitz did seem to be a straight-up guy and talented.
I've been using soundimports to look through speaker models. Select size, impedances to avoid passives coming up and then Fs. Still have more to do. So far nothing that has the slightest chance of matching a 70's speaker using an xover at 1500Hz or anything like it. True that high has it's problems but......
Also the spl plots show plenty of bouncing around at the deep bass end. I wonder what effect that will have when they are in a cabinet.
I'm also at odd with the forum in general. I recently installed some kit I have had for some years. It uses an F6 40Hz subwoofer and 80Hz F6 speakers. Xover 160Hz. Sensitivity of both 87dB. The woofer is 170mm. When we watch streamed movies where they just dump the effects in I often reach for the volume control when they run for too long. So just why do I need for instance 2 8" for the bass end? Music - no problems at all within the kits limitations.
LOL One problem is me I suppose. Design engineer. In situations like that I'm strongly driven to take notice of the above. The appeal in some respects is the possibility of just 2 speakers that don't need the woofer. The AR-6's used less volume than the above woofer.
Also the spl plots show plenty of bouncing around at the deep bass end. I wonder what effect that will have when they are in a cabinet.
I'm also at odd with the forum in general. I recently installed some kit I have had for some years. It uses an F6 40Hz subwoofer and 80Hz F6 speakers. Xover 160Hz. Sensitivity of both 87dB. The woofer is 170mm. When we watch streamed movies where they just dump the effects in I often reach for the volume control when they run for too long. So just why do I need for instance 2 8" for the bass end? Music - no problems at all within the kits limitations.
LOL One problem is me I suppose. Design engineer. In situations like that I'm strongly driven to take notice of the above. The appeal in some respects is the possibility of just 2 speakers that don't need the woofer. The AR-6's used less volume than the above woofer.
With high end material like Scan Speak and decent budget for realizing your project you never miss the target achieving good results.
Here an example where the sound got better than expected.
Cheapo no name Polypropylen bass driver with diy big dust cap reinforcing stiffness of the cone in a stone box made of marble. Reflex loaded and placed close to room boundaries.
It only sounds good, mighty and precise.
Much better than I thought it will be
https://www.diyaudio.com/community/...ription-subwoofer-gallery.207217/post-7494416
Here an example where the sound got better than expected.
Cheapo no name Polypropylen bass driver with diy big dust cap reinforcing stiffness of the cone in a stone box made of marble. Reflex loaded and placed close to room boundaries.
It only sounds good, mighty and precise.
Much better than I thought it will be
https://www.diyaudio.com/community/...ription-subwoofer-gallery.207217/post-7494416
I tried 6-7" drivers for mid-bas. They can be easier to cross to a midrange, since they behave nicer and smoother in the higher frequencies. But 2 x 8" woofers add some volume to reach 50-60Hz where I would like to cross smoothly to multiple subwoofers. Besides, my room is kinda "soft" so bass is easily absorbed, to an extent where I experience most speakers simply can't sound full or powerful in the mid and lower bass in my weirdly shaped living room.
I'm all for geeking all out on details as a full-blooded technician
. But when someone already done the job and the result is pretty awesome - I sleep better I've already tried SB WO24, RS225, Prestige L22, PurifiPTT6.5X, SB23NRX, Sica 10 SR 2,5 CP. Below 3-400Hz and lower.... The in-room measured difference is ridiculous small. The sighted sound-test, seems very close too - besides the Purifi's lack of SPL and low-end extension without port and passives... since I always go closed.
Maybe I should look into seeing if I could make the cabinet 30 cm wide - to house two Sica 10SR 2,5 CP around the KEF.
https://sica.it/wp-content/uploads/2021/02/Z006013.pdf
I could also make a larger profile/waveguide for the KEF midrange, to fit with the wider cabinet. Or maybe make 3 bowls with the KEF in the middle and 10" on top and bottom.... almost like this....
https://ikeahackers.net/wp-content/...AAAAZjM/MNagXja034g/s1600/IMG_0470-772277.jpg
A bit more.... trying to see if I can collect some info into same place... easier for other too, when seeking info 🤞
https://www.htguide.com/forum/missi...pment/927657-eight-inch-woofer-testing-report
https://www.htguide.com/forum/missi...pment/927657-eight-inch-woofer-testing-report
With all 8" I tested, simulated, it is hard go below 45-60Hz in a closed box. You have to do a Linkwitz transform. The SICA has the best ratio price quality in what you tested. You can go to the 8H2CP if you want a smaller dimension. This woofer sound good to my ears. Not as clean the magnesium but as good as a WO24p and better than a 22W8534 in the midrange.
Neither me or UK weather for some time allows me to check what sort of SPL I get at that level. Maybe late spring. I have good reason to think I will find it's adequate.
From a site that looks for deep bass - movies. Notice the main level --30dB around the 30Hz mark
https://i294.photobucket.com/albums/mm111/lfeman/alexanderchap12.jpg
I think these days it's fashionable to boost the power to make it's presence more apparent.
Music - it's not hard to find out the frequency range of just about any instrument. Music is also a commercial item. Why bother producing stuff that the majority of people wont hear because their kit wont reproduce it?
An amusing linkhttps://www.diyaudio.com/community/...-sub20hz-bass-on-a-budget.232978/post-3432071
Chuck out 110dB to feel or hear it???
It would still barely reach 90 dB/2,83 V (reference) and still 4 Ohm if wired series-parallel. Depressingly low efficiency. IMO not a good choice if one wants to use a dedicated subwoofer below these.
I didn't used, but maybe these instead?
https://faitalpro.com/en/products/LF_Loudspeakers/product_details/index.php?id=101030204
Or:
https://faitalpro.com/en/products/LF_Loudspeakers/product_details/index.php?id=101030200
I'm not seeing that in measurements but you be the judge of that for yourself.
https://www.htguide.com/forum/missi...nch-woofer-testing-report?p=928261#post928261
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I've missed where 90dB/2.83V/1m is a requirement especially when 10 channel DSP is going to be used. I found a woofer clean enough up to 1000Hz (3 aluminium shorting rings in motor) to be used in a threeway crossed at 400Hz that works well in closed cabinet under 40 liters. Watts are cheap and midrange can be atenuated so i don't see a real problem there, but that's me.
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Ok... I read all of it... swiftly, I'll admit that. But I see your point, when reading the graphs and curves. It definitely seems like a very behaved driver. My challenge with it, is. That it has a 4 ohm resistance. My amplifier might be ok with it. But I would like 2, to have a sensible cone area to move air, so 2 x 8 ohm in parallel would be nice.
Since I do not need the deeper frequencies... is there no other drivers capable of delivering the same low distortion, for the same price?
It looks like the Wavecor WF223BD02 and the SB Satori WO24 is the only one close to this performance. They both need 80 liters. But that's not so bad for a large tower speaker. Even with merely 55 liters for two 9" WO24 drivers, I get a F3 of 50Hz and a Q of 0,8.
The Wavecor might live fine in only 40 liters for two, to reach F3 at 50Hz.
All should be easily tamed with a bit of EQ.... which is needed anyway in the conjunction with multiple subwoofer and any normal listening room.
The KEF R900 that I aim to copy - more or less. Have roughly 70 liters inside - and since it's DIY... volume/size, can be flexible.
It really sucks to use some money on some driver. To realize afterward, that you should have saved a bit more, to get something that really fitted the bill.
Here.... a RS225 is 105 euro, a Wavecor is 140 and the Satori is 240. Logically, the Wavecor seems like balancing in the middle, with good specs, ok price and good construction. It was also the driver that he chose to continue with, for his (DaveFred) project.
Then he would have a nominal 8 Ohm speaker with around 80 dB/W efficiency after BSC. Okay, amp power is cheap nowadays but power compression comes at lower SPL levels for a low efficient speaker, becuase power is power and low sensitivity drivers needs a lot of it. My guess is that RSS210 don't have the mid and upper bass snap/slam as higher sensitivity woofers have.
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If I'm is "he". Then I'm sorry if I did not make it clear, that I always aim for 2 woofers, so that would have been RS225-8.
Not only looks, but also baffle-step and overall SPL, is the reason.
The lower in frequency, the more surface area we need. Using just 1 x 8" woofer, seems to me to be a rather "thin" sounding speaker. And pumping more power into it, to make it follow the rest of the drivers, seems like a bad plan too, since I have never heard anything like that, to produce a minimum of realism in sound reproduction.
Especially at lower volume, I have never - and I mean never - heard a smaller speaker produce realism. The drivers move at lot... and there is a sense of bass. But just a sense, not a realistic feeling.
I believe that 8" woofer are a nice compromise, that can reach down to a subwoofer and also reach most midranges, without beaming and distorting too much. All in a fair sized box.
IMHO, not depend on the speaker at low power but on the quality of the amplifier.
Small speakers need a very good amplifier to control well the small driver, not cheap.
A small speaker has rather some problems in bass extension for realism and power handling. I made small speakers with very big soundstage, one project published here : The bulldog
The more realistic bass I have heard is with 2x12" in OB. Not sure a big speaker in a box does so realistic.
In the midrange the magnesium driver is very realistic, very uncolored sound to my ears.
With your list of drivers I don't think you go wrong