What physics also dictate, is that this will lead to a very big cabinet.
You can't do that in a small 20 liter cabinet unless you want to compensate with cone excursion and therefor electrical power.
So @markbakk comment isn't such a strange thing.
Anyway, instead of using many words, just simulating is a lot more useful.
It might be worth having word with this man, He has at least on bass driver suitable for sealed
https://willys-hifi.com/collections...rs/products/peerless-p830667-sls-213-8-woofer
There may be others.
I can sympathise with the OP's desires. I grew up with AR-6's. Unobtrusive and rather good. The comments about crossovers are correct though. I'd suggest simulating the set up with designs that can be found. Boxsim is fairly easy to get into and has a good reputation. With Visaton drivers a full set of parameters are loaded. Also possible with Dayton as the files are available but the extra's are optional and used to generate a more complex speaker model. This link includes one to a lot of stock designs using it. They can help getting to grips with using it.
https://www.diyaudio.com/community/threads/boxsim-full-system-design-from-visaton-free.267787/
https://willys-hifi.com/collections...rs/products/peerless-p830667-sls-213-8-woofer
There may be others.
I can sympathise with the OP's desires. I grew up with AR-6's. Unobtrusive and rather good. The comments about crossovers are correct though. I'd suggest simulating the set up with designs that can be found. Boxsim is fairly easy to get into and has a good reputation. With Visaton drivers a full set of parameters are loaded. Also possible with Dayton as the files are available but the extra's are optional and used to generate a more complex speaker model. This link includes one to a lot of stock designs using it. They can help getting to grips with using it.
https://www.diyaudio.com/community/threads/boxsim-full-system-design-from-visaton-free.267787/
If you accept an f3 at maybe 55-60 Hz you can run the Fane Pro 8-225 in 22 liters vented. Looks pretty promising in WinISD. A high effiency driver with modest need for volume.
It should work well with a Peerless BC25SC06-04 or Scan-Speak Discovery H2606/920000
Could be an interesting combination, not only for the thread starter.
Anway, it would still need an x-over... useless without.
It should work well with a Peerless BC25SC06-04 or Scan-Speak Discovery H2606/920000
Could be an interesting combination, not only for the thread starter.
Anway, it would still need an x-over... useless without.
With an Le of 1,2mH and no clue (not that I know of...) about the use of copper round the magnet gap, why do you think this driver performs good at midrange while reproducing bass?
The Fane 8 or B&C 8NDL51 with the SS H2606-9200 is a great combo. If you want better top end, the Morel CAT378 is your best bet.
I've listened to speakers costing 5 figures with worse midrange than the 8PE21, 8NDL51 and Beta8A. Even the SB 6MW150D is a huge step above many dedicated mid drivers capable of the same mid extension as most SS and Seas 6s. It really depends on your ultimate preference in tonal detail, which is different in most of the drivers suggested. I'd stay a million miles away from a metal cone driver, with the exception of the tang band 4" titanium cone FR driver (forgot the model #).
Do yourself a favor and order a pair of Beta 8A from Madisound, costing only $30 in bulk OEM version. Put about 1.5mH in series with it and a pair of Morel CAT378 with 3.3 - 3.9uf in series, all on a 230mm wide baffle and listen to the results. Prepare to be amazed.
I've listened to speakers costing 5 figures with worse midrange than the 8PE21, 8NDL51 and Beta8A. Even the SB 6MW150D is a huge step above many dedicated mid drivers capable of the same mid extension as most SS and Seas 6s. It really depends on your ultimate preference in tonal detail, which is different in most of the drivers suggested. I'd stay a million miles away from a metal cone driver, with the exception of the tang band 4" titanium cone FR driver (forgot the model #).
Do yourself a favor and order a pair of Beta 8A from Madisound, costing only $30 in bulk OEM version. Put about 1.5mH in series with it and a pair of Morel CAT378 with 3.3 - 3.9uf in series, all on a 230mm wide baffle and listen to the results. Prepare to be amazed.
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Great woofer, only in a closed box it will do f3 @ 130Hz and vented it will do 75Hz without any additional boosting.
It wouldn't be my cup of tea.
If you are interested in using aluminium, and a removable front baffle, it might be worth doing a search (on diyaudio) for "Mid-range experiment with auto sound panel deadner..." by Remlab, mainly for the description of the aluminium/sorbothane sandwich front baffle used.
Have you actually listened to these units with that crossover? in what size box? Does such a simple crossover work? Remember i listen to a lot of classical and opera, not just jazz. Has to be smooth for violins and vocals.
@andyjevans I've mocked up some test enclosures with them together playing around with parts I had on hand. They were smooth on that sized baffle with those simple filters. Granted its not going to be perfect off axis, but if the turnover is around 3k, you'll end up with decent power response with the small WG on the CAT378.
I absolutely hate peaks in the midband. I listen to classical as well, just mainly piano, flute and woodwinds as well as cello. The 8NDL51 can go down to 60 easily in a larger vented box. Its just a superb driver in every way. Super consistent and never harsh, but enough detail to impress. A single inductor will work great if you want accurate spacial presentation. The CAT378 is also in the same league of character, just smooth and never irritating with a single cap. This tweeter won't ever complain, even just before it releases its magic smoke when you go too far with the volume - hasn't happened to me personally, but a few others have pushed them pretty hard with just a single small cap. Anything between 2 - 5 uF sounds nice coupled with a capable cone midbass.
I love first order filters if the drivers can handle them. Honestly, they could charge twice the money for the 8NDL51 and I'd still be a customer. I've gone through a few dozen of these in various designs. I cant fault it in any way other than it needs a big ported box to shine without a separate LF driver in a 2 way, at least 20 - 25 liters vented. I mainly use them from 200 - 1k as a midbass in a 4 way, but running them higher isn't a problem at all given you don't mind the off axis performance.
These days, with drivers like the 8NDL51, I dont really bother as much anymore with smaller drivers for 2 way designs, unless specifically needed. The mids are just as good and extended with this 8 as most other 6s.
I absolutely hate peaks in the midband. I listen to classical as well, just mainly piano, flute and woodwinds as well as cello. The 8NDL51 can go down to 60 easily in a larger vented box. Its just a superb driver in every way. Super consistent and never harsh, but enough detail to impress. A single inductor will work great if you want accurate spacial presentation. The CAT378 is also in the same league of character, just smooth and never irritating with a single cap. This tweeter won't ever complain, even just before it releases its magic smoke when you go too far with the volume - hasn't happened to me personally, but a few others have pushed them pretty hard with just a single small cap. Anything between 2 - 5 uF sounds nice coupled with a capable cone midbass.
I love first order filters if the drivers can handle them. Honestly, they could charge twice the money for the 8NDL51 and I'd still be a customer. I've gone through a few dozen of these in various designs. I cant fault it in any way other than it needs a big ported box to shine without a separate LF driver in a 2 way, at least 20 - 25 liters vented. I mainly use them from 200 - 1k as a midbass in a 4 way, but running them higher isn't a problem at all given you don't mind the off axis performance.
These days, with drivers like the 8NDL51, I dont really bother as much anymore with smaller drivers for 2 way designs, unless specifically needed. The mids are just as good and extended with this 8 as most other 6s.
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Profiguy: any experiences with 8bg51? It models well in 20-25l BR with reasonable extention below 50hz, but from datasheet it does not look good above 1k, it might be difficult in 2way with Fc around 1500hz.
This is very similar FR to most of the examples of 8NDL51s I see (copied from the web). The peak at 3.5k isn't typically as pronounced as in this graph and it diminishes a bit with a flush mounted driver. You won't really notice it when coupling it with a tweeter even first order around 2.5k. 2nd order will for sure suppress it more than enough to be buried enough. Without the series inductor on the woofer, you can tell it has a slight rising response curve with a peak at the end. There are however no other real peaks after that point, which is why you can get away with the single larger inductor. The BSC is factored into this already.
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@PKAudio The 8BG51 has a pretty bad surround reflection at 1k. You can see it in the impedance plot pretty well. Not a suitable driver for a 2 way. Big rubber surrounds aren't good for midrange linearity. Very rarely do I ever see a decent midbass with a traditional rubber surround. Purifi does some tricky thing with the shapes of their surrounds to combat this, but they charge alot of money for their stuff.
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UniBox thinks an SB23NACS45-8 with heavy fill needs 22l. If you can find a tweeter that is happy at 1.3kHz then you should be OK. SB do some that might work at low volume. Will's or Falcon can sell them.
I haven't tried them.
I haven't tried them.
this is more a bass driver imo, shouldn't be crossed above 500 hz 12dB slope passive :early breakups and really early odd harmonics.
This is like learning to swim. You can talk all day about it, but at some point you got to get your feet wet.
The helpfull people here try to find the right combination of drivers and cabinet for the thread starter.
In reality, there is an endless amount of speakers out there, commercial or DIYS, that are NOT done right in the true sense of the book. Many are even liked by their owners and a few sound better than predicted.
If the thread starter doesn't find anything right for his exotic aluminum construction that not even exists, he may simply fit the "wrong" kit to it. Chances are high he will like it, even as the combo plays worse than under best conditions.
Designing an x-over by him self may not be the best idea right now. Modern simulations only work with real world measurements. So you need a cbinet and real chassis at some point.
Even a first order network needs knowledge, measuring and usually more parts than a coil and a cap. Otherwise it will only protect the tweeter from instant destruction, but do nothing more in a audiophile sense. In more than 40 years of speaker DIYS I was unable to build a single combination with a first order x-over, simply because it did not go well. Even if on paper the chassis matched, the results hurt the ears.
You need a lot of measuring and listening to get things right, independent of order. There are some well made 6dB combinations, like Dynaudio. If you expect just two parts inside, be ready for a surprise: You will find a whole graveyard of caps, coils and resistors inside! Just to match two high class chassis in a first order configuration. Theory is not very practical with first order.
The helpfull people here try to find the right combination of drivers and cabinet for the thread starter.
In reality, there is an endless amount of speakers out there, commercial or DIYS, that are NOT done right in the true sense of the book. Many are even liked by their owners and a few sound better than predicted.
If the thread starter doesn't find anything right for his exotic aluminum construction that not even exists, he may simply fit the "wrong" kit to it. Chances are high he will like it, even as the combo plays worse than under best conditions.
Designing an x-over by him self may not be the best idea right now. Modern simulations only work with real world measurements. So you need a cbinet and real chassis at some point.
Even a first order network needs knowledge, measuring and usually more parts than a coil and a cap. Otherwise it will only protect the tweeter from instant destruction, but do nothing more in a audiophile sense. In more than 40 years of speaker DIYS I was unable to build a single combination with a first order x-over, simply because it did not go well. Even if on paper the chassis matched, the results hurt the ears.
You need a lot of measuring and listening to get things right, independent of order. There are some well made 6dB combinations, like Dynaudio. If you expect just two parts inside, be ready for a surprise: You will find a whole graveyard of caps, coils and resistors inside! Just to match two high class chassis in a first order configuration. Theory is not very practical with first order.
@Turbowatch2 The tons of extra components in dynaudio networks are for time delay. Dynaudio isn't the latest and greatest thing concerning 1st order filters. The other common misnomer is that a single cap or coil alone automatically constitutes a 1st order slope. Its the combination of electrical and acoustic slopes which govern phase shifts and therefore the final filtered responses. Dynaudio networks are very lossy and inefficient with their allpass delays and other compensating components. That being said some of their speakers are very nice. They just need alot of clean power to be driven properly.
You are all welcome to call me "Andy" rather than "thread starter". Don't worry - this will be built. I have the aluminium pieces ready and then need the wood pieces cut to size for top, bottom, front and back. The first build will be with the units and crossover out of one of my pairs of Mission 761. That is a Vifa 6.5" and D19 tweeter. The 761 is a sealed design, so I'm just making the cabinet bigger. This thread, which has been extremely useful and full of good things, is for a "better build". There are good designs for CA18RLY (Troels), SB17MFC (Bagby) and SB17NRX (Troels etc), so that's the current shortlist.
I'm keeping an eye open for a build using an 8" mid-bass also, so not ruling that out, though that might be ported design. I'm getting a clear idea that the experienced builders here demand better/lower bass. If I need to I can add another aluminium piece to the sides giving me 30 litres. The top and bottom would stay the same, just would need taller front and back panels.
I've been fired up about using a part aluminium cabinet for a while, but build has been delayed by having to build a few tube preamps for audio buddies to clear my stocks and make some room in the workshop.
I'm keeping an eye open for a build using an 8" mid-bass also, so not ruling that out, though that might be ported design. I'm getting a clear idea that the experienced builders here demand better/lower bass. If I need to I can add another aluminium piece to the sides giving me 30 litres. The top and bottom would stay the same, just would need taller front and back panels.
I've been fired up about using a part aluminium cabinet for a while, but build has been delayed by having to build a few tube preamps for audio buddies to clear my stocks and make some room in the workshop.
The LYC is a very successfull kit from the builder team I mentioned somewhere earlyer. I didn't have it on the radar because the chassis where unaviable for a while. It uses a principle (high pass woofer) that makes it bass capable in a too small cabinet. The build thread is really detailed and even shows an impedance correction for valve amps. Should be a great option too if you can live with a yellow woofer cone.