Honestly the SB23NRX is a good driver, to do better sonically will be hard in this small range of frequency, because this driver has enough low distortion. In a so small range of frequency it will be difficult to have a clear difference audible with the same technology ie paper cone or similar.
I'll go to a hard cone, in your list the aluminum cone could be the more neutral but I don't know how a RS225 sounds.
When you don't have the driver or listen to it in a speaker, it will be difficult to choose.
Perhaps you should add more constraints : what type of sound you want and you can live with : very detailled ? very clean ? very musical ? very dynamic ? etc.
A vastly quest !
Might not have been mentioned before:So, for 2 x 8-9" woofers, F3 at 50Hz, clean to min 500Hz in a closed box, and most detailed and correct possible sound, nice even/smooth look, that would match something like a black KEF Coax - and technically and sonically better than the SB23NRX.
Purifi, Excel, Texteme, Revelator, Ellipticor and the likes... that is simply too much money - IMO. Around 200 Euro a piece, would be around the max.
Let me also switch it around. What are the inherent drawback of the following drivers?
Wavecor WF223BD02
RS225-8
SB WO24P-8
And other drivers - if someone has specific drivers in mind - so that they can be sorted - and choices narrowed down.
By the way. Thanks to all for their patience and knowledgeI definitely hope that this also help others, to collect this information - smoothing out some myths too 🤞
Scanspeak 22W/8534G00 Discovery
John K. choice in his last NaO Note system. I use it as he did, for lower mid OB, 110 to 800 Hz. Ruler flat to nearly 1 kHz. Sounds detailed, dynamic, smooth. Better than any other 8" I've heard. Have rs225, tho haven't really listened; not tried sb23. Might not do F3=50 in closed box.
Yes it has.
I had an RS225 loaded in a simulator. 30L and <50Hz F3 looks dubious as it does with the Visaton.
It's also put me off the sub 25Hz Fs drivers. Strange wobbles in the spl graphs down low in the bass range.
Also the U22 seems very cheap at the LX521 webstore; not sure if you need to be a LX521 owner to buy them, though.
Now, looks! Not to scale for WO24P but you get the idea. For me, Fountek looks best - faux-Accuton!
Now, looks! Not to scale for WO24P but you get the idea. For me, Fountek looks best - faux-Accuton!
Great photo-shop thereAlso the U22 seems very cheap at the LX521 webstore; not sure if you need to be a LX521 owner to buy them, though.
Now, looks! Not to scale for WO24P but you get the idea. For me, Fountek looks best - faux-Accuton!
Actually, the Fountek also seem to have the best parameter for the job. It has much lower VAS and looks pretty nice + I get my alu-cone too, so I can sleep nicely at night, knowing no paper is going to color my sound
. My KEF is all black though... but I still appreciate the effort a lot Though.... The fountek has no proof of shorting rings, copper sleeve or distortion measurements. And no known design with the WF222. So I would be a first-mover.... if I buy'em
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To round a bit.
Qms is roughly a partner with low VAS and the need for less box volume - since Cms is the true physical resistance - meaning - the distance the cone can be moved with a fixed force - correct?
Paper and paper-mixed cones have higher inner damping, with the compromise of "eating" up details in the acoustic output to smooth the response - true - just a little or simply ignorant - unless specified in the datasheet like with the Silver flute?
Most parameters will still give you quality bass with most woofers, since it is only a matter of box volume, closed vs reflex, max SPL and lowest possible F3, because all the other bells and whistles, mostly matter in the lower midrange and up - around 500Hz - true?
Qms is roughly a partner with low VAS and the need for less box volume - since Cms is the true physical resistance - meaning - the distance the cone can be moved with a fixed force - correct?
Paper and paper-mixed cones have higher inner damping, with the compromise of "eating" up details in the acoustic output to smooth the response - true - just a little or simply ignorant - unless specified in the datasheet like with the Silver flute?
Most parameters will still give you quality bass with most woofers, since it is only a matter of box volume, closed vs reflex, max SPL and lowest possible F3, because all the other bells and whistles, mostly matter in the lower midrange and up - around 500Hz - true?
Of course. My first speaker to make active, was a Dali Evidence 870. I simply disconnected the passive cross-over and added a 3 way active DSP controlled amplifier. What I found, was these woofers could not play deep, but had a very light, accurate and snappy ability to play detailed bass.
I knew so little back then. And mostly I remember that mid-woofer sound. The deeper bass could simply be handled by subwoofers - which I learned later on - after the speakers were sold, and I experienced many other factors of sound, like the midrange/tweeter combination and the importance of those.
Down the line - I have tried to find woofers for my DIY projects, that had that "snap" and detail again. And after listening to an ocean of systems and speakers - both commercial and DIY. I'm now trying to search via the more scientific approach. That is why I asked to open up this tread again. To see if I could think my way to obtain that sound again, with my current knowledge and also being quite happy with my subwoofers and upper frequencies.
The SB23NRX was a second hand thing. And back when I bought them, few were using DSP and even thought of putting them in a smaller cabinet.
I thought that maybe the 22W Discovery, would resemble the woofers in my old Dali speakers. But it seems, that to be a true update. I could get the Wavecor's for around 30 Euro extra a piece, and achieve way better cooling around the voice coil, lower distortion all over, deeper extension - even in smaller volume and some of the highest Qms values I have ever seen in any datasheet. Leading me to think, that this might give me a very close to the same performance as the WO24P - which I quite like - but at half the price.
SB23NRX seems just shy of snappy and detailed - and maybe a bit warmer and less detailed than I would like. And they can't do that "snap" with my favorite test track - Hotel California - live 1994. In the beginning of the track, there is a shift between a wack on a drum, where they take turns of being silenced right after the wack, and letting the drum "ring out". One wack/stop = "BOM" - next wack/let go = "BOMMMMMM". If that makes any sense
Maybe I just need to adjust my volume for the driver, to a lower Q. Maybe you can't simply EQ the peak of a high Q system, but actually need to give drivers the needed volume to obtain a given low Q, and cross when needed - ignoring whether the driver plays deeper. My current volume of 60 liters for two 8" SB23NRX - gives me a Q of 0,8. Maybe that is simply to high and result in a bit more warmth than I prefer - even though I EQ them flat. Does that make sense?
digitalthor: thanks for detailed description. I asked because this thread grows and contains a lot of various recommendations. It is good, it is very informative and comprehensive, but the merit is to find the woofer that meets your sound quality criteria, and in this case only few posts in this thread give you what you need or at least give you a directions.
Frankly, I hesitate to to communicate openly my listening experiences of the drivers. It is sometimes against general view of certain drivers and my view will not be popular I assume. Anyway, here is my experience, take it or leave it:
SB23xxx (CAC if I recall well, ~40l BR) - your perception of the sound of this driver is correct, or at least matches my experience. SB17 drivers are very similar.
WO24P (45l BR, 45l closed) - better then SB23 and SB17, though basic characteristics are very similar.
They both play deep, but that is the only good I can say about them. Skilled designer with good ears can get them sounding almost good, but once you compare to other woofers the difference is quite clear.
22W Discovery, I did not work with these, but based on 26W Discovery I assume good bass quality, lighter snappy fast detailed kind of the bass
Sica 8" (~25l BR, 25l closed) is good. Good balance of low end extension, detail and required volume, + it works well in closed box. It is good allrounder.
21W Classic (37l BR, 33l BR) excellent, this one really shows what scan speak bass quality is about, not overly snappy but the detail and certain ability not to sound boomy is great. It has firm bass and in that regard it is better then 22W Revelator.
U22REX is very likely, and based on recommendations of other, very good as well.
WF223BD 8ohm, I used two in one loudspeaker, ~70l in total, BR, go very deep, but softer kind of the bass, less snappy compared to 21W Classic
22W Revelator (~33l BR) softer sounding compared to 21W which is not complaint. Excellent woofer.
NE22W 4 ohm (38l BR) sound was similar to NE223. Very good.
I could live with all woofers mentioned above except SB and WO24. These to sounded unacceptable, and I spent a lot of time trying.......
If you want snappy, vivid, faster kind of bass, go with lower volumes, lower GD, BR or closed even better.
Even BR enclosure benefits from damping material inside if you want bass quality, lower midrange clarity improves.
Be careful with 200-500Hz area, it is not easy to get measurements accurate indoor, gating often lead to the wrong level in that area. Any lift in that are often sounds wide muddy and lowers the clarity.
Hope this helps a bit. It is full of subjective terms but I think it is what we discuss, what we are after. Describing the sound quality and impressions are about subjective terms. I added comparison with other woofers to give you the full picture and background for my opinion of SB and WO.
Frankly, I hesitate to to communicate openly my listening experiences of the drivers. It is sometimes against general view of certain drivers and my view will not be popular I assume. Anyway, here is my experience, take it or leave it:
SB23xxx (CAC if I recall well, ~40l BR) - your perception of the sound of this driver is correct, or at least matches my experience. SB17 drivers are very similar.
WO24P (45l BR, 45l closed) - better then SB23 and SB17, though basic characteristics are very similar.
They both play deep, but that is the only good I can say about them. Skilled designer with good ears can get them sounding almost good, but once you compare to other woofers the difference is quite clear.
22W Discovery, I did not work with these, but based on 26W Discovery I assume good bass quality, lighter snappy fast detailed kind of the bass
Sica 8" (~25l BR, 25l closed) is good. Good balance of low end extension, detail and required volume, + it works well in closed box. It is good allrounder.
21W Classic (37l BR, 33l BR) excellent, this one really shows what scan speak bass quality is about, not overly snappy but the detail and certain ability not to sound boomy is great. It has firm bass and in that regard it is better then 22W Revelator.
U22REX is very likely, and based on recommendations of other, very good as well.
WF223BD 8ohm, I used two in one loudspeaker, ~70l in total, BR, go very deep, but softer kind of the bass, less snappy compared to 21W Classic
22W Revelator (~33l BR) softer sounding compared to 21W which is not complaint. Excellent woofer.
NE22W 4 ohm (38l BR) sound was similar to NE223. Very good.
I could live with all woofers mentioned above except SB and WO24. These to sounded unacceptable, and I spent a lot of time trying.......
If you want snappy, vivid, faster kind of bass, go with lower volumes, lower GD, BR or closed even better.
Even BR enclosure benefits from damping material inside if you want bass quality, lower midrange clarity improves.
Be careful with 200-500Hz area, it is not easy to get measurements accurate indoor, gating often lead to the wrong level in that area. Any lift in that are often sounds wide muddy and lowers the clarity.
Hope this helps a bit. It is full of subjective terms but I think it is what we discuss, what we are after. Describing the sound quality and impressions are about subjective terms. I added comparison with other woofers to give you the full picture and background for my opinion of SB and WO.
It does - nice write up - thank you
Only thing I can really see differently with the 21W classic from Scan-speak. Is the super soft suspension of almost 2mm/N. That is 2-3 times softer than any other driver ever mentioned. Could be the reason why it might "fly" easier forth and back, making it able to "snap" easier - just a theory.
When speaking to Ulrik, when we have our annual Christmas gathering. He mentioned the SB23NRX being the first generation, and motor design did improve later on. Still a fine driver - but I want something better
He then continued with the suggestion of the SB20PFC30-8. It had never motor system and mainly cost was down, because they used a simpler plastic basket, which was still very stiff/rigid and inert, since a metal ring was cast inside the plastic basket.Also, just noticed now. The Discovery 22W has 1,22mm/N. Again, way softer than other drivers. Low cone mass too, like the PFC and Seas U22REX P/SL - which also has a very high softness of 1,7mm/N.
Actually. The new Dayton Signature 6,5" is exact half the price of the 8". So I could copy the KEF Reference 5 instead.
It can potentially measure awesome with 4 x 6,5" woofers.
https://www.spinorama.org/speakers/KEF Reference 5/KEF/index_vendor.html
Though... I'm a bit in doubt whether 4 smaller woofers represent the same as 2 larger ones - not to go OT with smaller woofers - too much
And now that we're at it. Does woofer placement truly make a difference in distributed bass of a given room? It could be logical, that having more woofers playing the same frequency, would create fewer reflection problems in a room - no?
It can potentially measure awesome with 4 x 6,5" woofers.
https://www.spinorama.org/speakers/KEF Reference 5/KEF/index_vendor.html
Though... I'm a bit in doubt whether 4 smaller woofers represent the same as 2 larger ones - not to go OT with smaller woofers - too much
And now that we're at it. Does woofer placement truly make a difference in distributed bass of a given room? It could be logical, that having more woofers playing the same frequency, would create fewer reflection problems in a room - no?
For those who looking for something which is an almost vintage design and not look very nice today but have very nice sound and almost flat linearity, https://en.toutlehautparleur.com/br...ker-audax-hm210g6-8-ohm-8-27-x-8-27-inch.html
I will add to my previous post that it is valid for all mentioned drivers used for woofer duty >500Hz.
Savan: thanks for the recommendation, I was looking at this paper Audax recently and thought it could be good. It models well in 40l BR. HM210CP. HM210Z12 and C0 are likely good sounding woofers as well.
Savan: thanks for the recommendation, I was looking at this paper Audax recently and thought it could be good. It models well in 40l BR. HM210CP. HM210Z12 and C0 are likely good sounding woofers as well.
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Old good extremely linear and good sounding Audax speaker https://en.toutlehautparleur.com/br...ker-audax-hm210g6-8-ohm-8-27-x-8-27-inch.html from HM series.
For those who want try great Audax project. FRD and ZMA made by Clio while speakers was mounted in box from picture! Cosower simulated than project finished with great sound and dynamic.
Note that https://en.toutlehautparleur.com/br...ker-audax-hm210g6-8-ohm-8-27-x-8-27-inch.html is not treated paper cone and you will need to treat it with https://plaidonline.com/products/mod-podge-gloss-64-oz-cs15091 , I have bough 5 years ago https://en.toutlehautparleur.com/speaker-audax-hm170g8-8-ohm-6-54-x-6-54-inch.html very nice sounding driver in my TL speaker project, it was not paper treated so i treated it with ModPodge and got almost the same graph measurement as per datasheet, without treatment it have some distortions in 2-3 k and up region!
For those who want try great Audax project. FRD and ZMA made by Clio while speakers was mounted in box from picture! Cosower simulated than project finished with great sound and dynamic.
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