I've been looking at more 8" units since I share your desire for deeper bass if it's possible in sealed. My enclosure is 25ltr so a bit more scope.
For deeper bass in a 25 litre sealed box these look possible...
Kef B200 SP1014, F3 = 45, Qtc = 1.28 (+2.8db hump at 70Hz)
SB23MFC, F3 = 48, Qtc = .68
Peerless 830667, F3 = 49, Qtc = .97
SB23NRX, F3 = 52, Qtc = .85
Tangband W8-1722, F3 = 53, Qtc = .88
Dayton RS225-8, F3 = 55, Qtc = .68
The problem for me is that apart from the Kef, I can't find an existing crossover design for any of these. Can anyone help?
For deeper bass in a 25 litre sealed box these look possible...
Kef B200 SP1014, F3 = 45, Qtc = 1.28 (+2.8db hump at 70Hz)
SB23MFC, F3 = 48, Qtc = .68
Peerless 830667, F3 = 49, Qtc = .97
SB23NRX, F3 = 52, Qtc = .85
Tangband W8-1722, F3 = 53, Qtc = .88
Dayton RS225-8, F3 = 55, Qtc = .68
The problem for me is that apart from the Kef, I can't find an existing crossover design for any of these. Can anyone help?
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http://www.mes-enceintes-acoustiques.com/2017/12/kef-b200-sp1014.html
you will need with it as the RS225, a 3" full range with a XO < 500 hz. More or less the same with the Peereless.
The NRX is certainly easier to cross higher and the MFC iirc has very low distorsion but not sure the last is what is good for a bass player.
The Tangband numbers are attractive but no idea about this driver. The SB23MFC migth be the easier but I fear about a too much "dead smooth" sound for your taste.
Most are more bass drivers than midbass woofers. I would choose one I can cross around 800 hz. There are excellent 3" and not that expenssive imho.
the nrx is certzinly the one to choose for your tastes. (though the Dayton should have better bass line but less good mids and not as high cut-off facilities)
you will need with it as the RS225, a 3" full range with a XO < 500 hz. More or less the same with the Peereless.
The NRX is certainly easier to cross higher and the MFC iirc has very low distorsion but not sure the last is what is good for a bass player.
The Tangband numbers are attractive but no idea about this driver. The SB23MFC migth be the easier but I fear about a too much "dead smooth" sound for your taste.
Most are more bass drivers than midbass woofers. I would choose one I can cross around 800 hz. There are excellent 3" and not that expenssive imho.
the nrx is certzinly the one to choose for your tastes. (though the Dayton should have better bass line but less good mids and not as high cut-off facilities)
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With the W170S I get F3 of 63Hz sealed and 53 vented. The roll of rate down to ~35Hz is more or less the same as sealed. I'm using Boxsim and Visaton chassis. I could use Dayton as they provide ZMA and FRD files needed for xover design and also to see what a build is likely to do. Boxsim loads of Visiton drivers have these built in. Visiton also suggest box sizes and tuning for a number of their drivers on their web site for both sealed and vented. I chose 20L as nice and small.
My reason for looking at 8" relates to cone movement at the bass end. Xmax. This limits the SPL that can be achieved. For a given SPL 40Hz needs more cone movement than 100Hz. Increasing size reduces the movement needed, I can achieve an max SPL of 100dB at 100Hz on both with the W170S. At 40Hz things are a bit different. 85dB sealed and 95 vented. With a drive of 2.83 Vrms both generate 85dB at 100Hz and up also for some portion lower. I have neighbours too so can't play loud. My amp "may" be able to overdrive them. To get round that I would probably need a 10" or bigger and have to go 3way. I'm also considering the typical content of music, Take something loud, a bass drum. Fact is that will be about 100Hz, Probably higher. Fact is that if I bought small suitably rated speakers and sine tested them it would fry the drivers,
Whoops - Xsim uses FRD and ZMA files to design cross overs mouse wheel style. Boxsim has calculators but like all assume a pure resistance. Tweeters are more like that away from resonance. On a driver the apparent R may need changing but it also has an optimiser. That can be used to polish thing up - using it needs a bit of thought at times. Then there is likely to be need for some manual adjustments, These needed to refine the phase relationship between the 2 drivers at xover. The optimiser also works on correcting that. LOL It may give pretty good results but at an xover F that you don't want. This doesn't mean that you can't use the one you want.
My reason for looking at 8" relates to cone movement at the bass end. Xmax. This limits the SPL that can be achieved. For a given SPL 40Hz needs more cone movement than 100Hz. Increasing size reduces the movement needed, I can achieve an max SPL of 100dB at 100Hz on both with the W170S. At 40Hz things are a bit different. 85dB sealed and 95 vented. With a drive of 2.83 Vrms both generate 85dB at 100Hz and up also for some portion lower. I have neighbours too so can't play loud. My amp "may" be able to overdrive them. To get round that I would probably need a 10" or bigger and have to go 3way. I'm also considering the typical content of music, Take something loud, a bass drum. Fact is that will be about 100Hz, Probably higher. Fact is that if I bought small suitably rated speakers and sine tested them it would fry the drivers,
Whoops - Xsim uses FRD and ZMA files to design cross overs mouse wheel style. Boxsim has calculators but like all assume a pure resistance. Tweeters are more like that away from resonance. On a driver the apparent R may need changing but it also has an optimiser. That can be used to polish thing up - using it needs a bit of thought at times. Then there is likely to be need for some manual adjustments, These needed to refine the phase relationship between the 2 drivers at xover. The optimiser also works on correcting that. LOL It may give pretty good results but at an xover F that you don't want. This doesn't mean that you can't use the one you want.
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Looks like there is no one else but Trowels in DIY world . Ain't that sad ? There are 500 pro designers in retail world one can choose from and be prickly about when it comes to spending money but "rebellious " diy world has only one tool in its shed .Trowels .!! That's after decades of contempt of a system of oppression...
Hahaha ...
Hahaha ...
Thanks for the B200 French site. I do speak good French so very useful. I have a pair of B200 so they would get me up and running.
Troels' Discovery could be good. In 25 litres sealed the F3 is 62Hz Qtc = .74 - would be good lower, so might have to try a port. I'd have to obtain the crossover values from Jantzen though. I'll have to look more carefully at this design since he uses a 1.8K crossover with the D2608, so that's possible even without a waveguide. Has anyone tried the 22W4534? No idea how fibreglass sounds for the cone.
Here's the B200 SP1014 frequency responses off that site. I have no experience designing crossovers, but does this look like you could use a first or 2nd order crossover coming in at above 500Hz? There are loads of B200 units available used in the UK so it would be useful to know.
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you didn't understand my post : I just wanted to show him the midwoofer used in that loudspeaker as a proof of concept it goes low and high enough in magnitude! Are you oneof the 500 or still searching ? 😉
Do not use the tweetern use instead a sb26cac in augerpro 3d printed horn for it, it will blend better with the 8".
Or just use the CA18rly free kit with its good 22 taf/G and buy later a mono sub with plate amp for what is below 60/80 hz.
What will you do above 500Hz? I'd say the change above that will cause complications. The Scanspeak part is 4ohm which may not suite your amp. It also has a change of behaviour at a 1000Hz. That peaks at 3kHz. There have been comments about all older speakers - things have moved on design wise thanks to computers. The older stuff tends to have problems in none ideal places and you need to get to tweeter land or start looking at adding full range stuff maybe a concentric but that will very probably have more extreme beaming than a tweeter and versions of those intended for higher F will have less beaming than ones that can work from lower. Or go 3 way.
Sticking to the W170S it has an unfortunate peak at 5Khz. A 2nd order xover at 2.5kHz will tame that and some 3kHz tweeter will be ok at that. I have seen a design that crosses this one over at ~3.5kHz. That introduce ripple due to the peak. Going one order higher on the xover may or may not help.Probably not as 5k is too close to 3.5. 😉 Add an extra and the optimiser may take it out chasing cross over phase
Go to the W200S and peaks crop up earlier. Acoustic Research and their AR-6. They used an 8" woofer with a resonant frequency of 23Hz and crossed over at 1500Hz. There are tweeter that can get that low. 23Hz seems to be a bit of ££££ problem if one can be found.
Experience - purely under simulation but with a package that does have all the data needed to help make the simulation as accurate as it can be. One of the horn packages is said to be the best in this respect but it's not easy to see how to use it. There is a bit of an intro on a site called subwoofer.org that indicates how to set it up for none horns.
I'd suggest you have a go at using Boxsim, Google will bring up a link on this site that mentions an easier way to get into it. There are a lot of stock designs available as project files. Xovers can be pinched from it or you can go your own way using the usual calculators that are also included as is impedance correction. Also L pad calculations using standard parts. You just state dB loss needed. The optimiser wont add things. Just change values so say you want a notch filter your on you own. The web may help.
The various plots give a pretty clear picture of the expected results. One of the load options is parameters as measured in the designed box. Useful if some one wants to go that way but a full set of measurements need acoustic phase as well as the usual others. Boxsim's chassis files include these and they can also be downloaded for Dayton. Others - don't know of any.
I understood your post alright and i stand by what I wrote 🙂 I only dumpster dive. Usually those who are still searching put their 2 year old boxes on the curb because nobody wants an "old tech" anymore. That's when my time comes.
All my gears where purchased second hand but the dac that born from an initiative of mine and 2 people to ask a diy platform back of an old philips pcm chip to a welll known brand in Serbia that makes euphoric & euphonic DACs, cause we were unhappy of a terific cooperative thread here. So I can understand you !
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It looks like being able to cross to tweeter at the usual frequencies, and historically, there have been kits like that.
Find a tweeter of the same sort, with the same info graphs, and we are in business.
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I'd choose something more modern than the D19-TD05 supronyl dome. Most of the other soft domes are better and more resolving in performance. The 22TAF is my first pick, but I currently favor Alu/Mg alloy domes myself.
Thanks, Interesting one. Damped dome to allow it to work at somewhat lower frequencies. £60. Seems to be the going rate for decent beaming and lower xover F's. Not down to the domed mid range levels though.
🙂 I give up on trying to get Andy to see if he can make used of what WineHQ and PlayWithMac offer to allow win software to run on a mac. No guarantee that it would work out but it may well do on some packages.
I've mentioned F6 figures. Reason is that it's not that unusual for commercial stuff to use it rather then F3. I know exactly what to expect with F6 and trying to get lower than I have starts to come into box and speaker size problems on a 2 way. For instance an F6 of 30Hz would need a ~50L box. So far easy xover and 8in seems to indicate an alu cone. I'm a bit queasy about those on tonal changes thanks to something I did with a smaller venue amp a while ago.
< I've mentioned F6 figures. Reason is that it's not that unusual for commercial stuff to use it rather then F3.
The mid-bass I'm most interested in is currently the SB23NRX with either SB26RDC or SB6ADC crossing over somewhere around 1.8K-2K. In my 25 ltrs sealed, F3 is 51.5Hz and F6 just over 40Hz. I've been searching for crossovers and did find a lot of useful information in this thread:
https://www.diyaudio.com/community/threads/sb-acoustics-tw29r-sb23nrxs4.231481/page-2
Very useful input from System7 on the thread and many crossover ideas. I haven't seen any other crossover designs for the SB23NRX though it seems quite popular.
The mid-bass I'm most interested in is currently the SB23NRX with either SB26RDC or SB6ADC crossing over somewhere around 1.8K-2K. In my 25 ltrs sealed, F3 is 51.5Hz and F6 just over 40Hz. I've been searching for crossovers and did find a lot of useful information in this thread:
https://www.diyaudio.com/community/threads/sb-acoustics-tw29r-sb23nrxs4.231481/page-2
Very useful input from System7 on the thread and many crossover ideas. I haven't seen any other crossover designs for the SB23NRX though it seems quite popular.
I see where you're coming from. Getting a bigger 2 way to do the entire bass register cleanly and evenly is a massive challenge. Usually there will be large compromises made in either fundamental low end or midbass resolution. Very rarely do you get both to be acceptably even and still have good LF dynamics left. This is why I rarely ever entertain typical 2 way designs anymore and opt for at least a dual 6" 2.5 way or 10" 3 way with a large dome mid or 4 to 6" cone mid handing over to a capable 1" metal dome.
The Seas U18RNX-P is one of the best easy to source midbass drivers for a 2 way IMO. The midrange response is very smooth, yet has excellent resolution, not that typical veiled poly cone sound you get with drivers like the well regarded Vifa P17-WJ. Getting rid of the dust cap is the best way to avoid the typical sub- 1k resonances which really hurt midrange resolution and perceived "speed" of midbass. It also keeps the driver VC cool in a sealed enclosure for less power compression, which is more of an issue than some people believe.
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The Seas U22REX-P also looks like a candidate for a sealed box 2 way. You may need a tiny LCR to tame the minor 3k bump, but otherwise its an easy driver to work with. I've built a 2 way with this one using the Morel CAT378. They integrate very well in character and have a relaxed, but tight sound signature. Really good sensitivity too and easy to drive.
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😉 It was an @system7 post that encouraged me to look at boxsim also mentioning the database of designs. He does use boxsim but prefers the older version. He also explains why he favours Visaton drivers - more sure of how the parameters have been measured. There is a speaker database that shows plots of all sorts of things on a lot of drivers but no signs of where the info comes from. It includes factors that aren't shown in data sheets. This is the site. It gives 1wat spl and max. Even acoustic phase.
https://loudspeakerdatabase.com/
You could try googling SB23NRX crossovers maybe also mentioning the other and 2 way. It will probably bring up posts.
This is the spl plot of the woofer
https://sbacoustics.com/wp-content/uploads/2020/02/8-SB23NRXS45-8-GRAFIK.jpg
You can see some of the factors mentioned about 8" woofers are apparent that tend to reduce with smaller. Beaming - I prefer the pictorial view Visaton provide but clearly it's starting at 1k on that one. This one is similar to the SB unit but maybe a touch smoother.
https://www.visaton.de/en/products/drivers/woofers/w-200-s-4-ohm
I have never built a speaker but have played on and off on design for a long time sometimes with a calculator. I'm well aware of what physics does where bass is concerned in respect to speaker and cabinet sizes. 😉 Boxsim has rammed it home even more especially in the cone excursion area. So I have a w170s design that it's hard to fault under simulation. My concern is SPL at the 30Hz level. If I used 2 it wouldn't be a problem but 40L would be needed. I stick a 200mm in and use the suggested tuning. It gives too much bass boost in the 100hz region with 20L. I look at the alu version and wonder what on earth has gone on with the beaming. Suppose the cone is so stiff higher F's don't get distributed evenly.
There is another option. Go 3 way as a mid does not need a large cabinet. That can be small but the woofer end still needs to handle SPL.
I bought a Dayton mic so that I can measure SPL. USB so that will be calibrated. 😉 Guess I am going to have to set up and measure what going on when we are watching a film. The current set up uses a 40Hz F6 woofer, 170mm too but when the effects are going on for some time I sometimes reach for the volume control to avoid annoying neighbours but have no idea what that SPL is. Speech levels on some are rather low. Bad mix, hardly hear it followed by way to high at times.
System7 has several crossover designs using the W200S. It is indeed a contender, though I think the SB23NRX is a bit better. Believe me, I've googled that one and only one crossover design comes up as listed in post 296. That thread has System7's Visaton W200S crossovers in it too.
The SB23NRX crossover uses the SB29RDC. I'm having a hard time deciding between that and the SB26ADC....
The SB23NRX crossover uses the SB29RDC. I'm having a hard time deciding between that and the SB26ADC....