Yep, everyone would like to go as small and cheap as possible of course, which is fine and understandable goal.
If one wants to make an "impressive speaker" it should be capable to make some "standard" bandwidth and SPL, like what sound professionals use to make the music and sound. One could look for standards online, and it seems work with music is done about at 80-85db level, A or C weight. Take some of these numbers as target. Assume 2-3m listening distance, assume some headroom for dynamics like 15db or 20db, whatever. Example, since 85db is quite loud let's take 80db, add 6db for 2m listening distance and 14db for dynamics for easy math makes 100db capable speaker on the conservative side to save on cost and size. Bandwidth from 40Hz up is already quite nice, going any lower would mean bigger speaker so let's take that, this would be kind of a minimum for "impressive" speaker for anyone who is used to box store speakers.
Sensitivity would depend on how much power there is available. Ton of old AB amps and modern chip and class D amps provide someting like 40W to 4-8ohm load, of course there is more powerful and weaker stuff as well, but 40W could do very roughly roughly 15db of amplification compared to 1W, so you'd need a 85db/1w/1m sensitivity for the speaker from 40Hz and up to meet the spec. Now one could go and check out what this would actually mean, what's the size and cost.
Quick scan with vituixcad box simulator shows all 10" woofers I had there can do ~85db@~40Hz with 1W in a ported box, box size varies from small to big. So, a 10" could be just fine for this example requirements. For closed box there was few 12" that could do it in a reasonable sized box.
These numbers are about what waxx suggested. Make it more impressive and size and cost goes up, make it cheaper and smaller and it's not as impressive, not capable of music production levels, the levels your music was mixed on and sounded best for the engineer.
edit. andy19191 posted about the same time 😀 similar numbers there as well.
If one wants to make an "impressive speaker" it should be capable to make some "standard" bandwidth and SPL, like what sound professionals use to make the music and sound. One could look for standards online, and it seems work with music is done about at 80-85db level, A or C weight. Take some of these numbers as target. Assume 2-3m listening distance, assume some headroom for dynamics like 15db or 20db, whatever. Example, since 85db is quite loud let's take 80db, add 6db for 2m listening distance and 14db for dynamics for easy math makes 100db capable speaker on the conservative side to save on cost and size. Bandwidth from 40Hz up is already quite nice, going any lower would mean bigger speaker so let's take that, this would be kind of a minimum for "impressive" speaker for anyone who is used to box store speakers.
Sensitivity would depend on how much power there is available. Ton of old AB amps and modern chip and class D amps provide someting like 40W to 4-8ohm load, of course there is more powerful and weaker stuff as well, but 40W could do very roughly roughly 15db of amplification compared to 1W, so you'd need a 85db/1w/1m sensitivity for the speaker from 40Hz and up to meet the spec. Now one could go and check out what this would actually mean, what's the size and cost.
Quick scan with vituixcad box simulator shows all 10" woofers I had there can do ~85db@~40Hz with 1W in a ported box, box size varies from small to big. So, a 10" could be just fine for this example requirements. For closed box there was few 12" that could do it in a reasonable sized box.
These numbers are about what waxx suggested. Make it more impressive and size and cost goes up, make it cheaper and smaller and it's not as impressive, not capable of music production levels, the levels your music was mixed on and sounded best for the engineer.
edit. andy19191 posted about the same time 😀 similar numbers there as well.
Last edited:
Hmmmm, now where have I seen this before -
Oh, this looks quite like my speakers -
Untitled by A H, on Flickr
by A H, on Flickr
Closed box c.40L (old repurposed Akai SW125), WO24P-4 9.5" woofer, Morel EM1308 2.25" mid and Morel ET448 Tweeter. Currently DSP crossover but working on a passive one.
My preference would be for a closed box options around the 35-40L with F3 at 45-50hz, F10 less than 30hz (WO24P-4 just about does this so does the marginally cheaper SB29NRX-8). If the parts count (less woodwork) can be kept below £1000/$1250 for a pair then that would be good.
Oh, this looks quite like my speakers -
Untitled by A H, on Flickr
by A H, on Flickr
Closed box c.40L (old repurposed Akai SW125), WO24P-4 9.5" woofer, Morel EM1308 2.25" mid and Morel ET448 Tweeter. Currently DSP crossover but working on a passive one.
My preference would be for a closed box options around the 35-40L with F3 at 45-50hz, F10 less than 30hz (WO24P-4 just about does this so does the marginally cheaper SB29NRX-8). If the parts count (less woodwork) can be kept below £1000/$1250 for a pair then that would be good.
The Warfdale Dovedale is 417 mm x 370 mm x 660 mm, so with 18mm wood we got about 78L to play with says my calculation. Count about 15-20L for the high and mid section so about 50 to 65L for the woofer. Which quality 10 or 12" can fit that with a response more or less 40Hz F3 without costing a fortune?
I know some faital 10" that fit that, but they will be too expensive. So we need to set a budget limit also. High quality mid and tweeters toghetter can be had for 100€ (or maybe even less), but for a woofer you need to count 200€ as max budget i think. Then we have some good options.
I personally think the 10" SB29NRX75-8 in a 50L ported would be a good candidate that is not to expensive. You got a good response within 50 below the wanted 40Hz and usable quiet high (500Hz) so easy to cross to a mid driver of choice. Sensivity is also more than enough. Combine it with a SB26ADC or similar tweeter and a fitting mid like SB17MFC35-4 or SB17NBAC35-4 and you could have a decent priced recipe. Other combo's are also possiible off course. I just went trough drivers i know that would fit.
I know some faital 10" that fit that, but they will be too expensive. So we need to set a budget limit also. High quality mid and tweeters toghetter can be had for 100€ (or maybe even less), but for a woofer you need to count 200€ as max budget i think. Then we have some good options.
I personally think the 10" SB29NRX75-8 in a 50L ported would be a good candidate that is not to expensive. You got a good response within 50 below the wanted 40Hz and usable quiet high (500Hz) so easy to cross to a mid driver of choice. Sensivity is also more than enough. Combine it with a SB26ADC or similar tweeter and a fitting mid like SB17MFC35-4 or SB17NBAC35-4 and you could have a decent priced recipe. Other combo's are also possiible off course. I just went trough drivers i know that would fit.
Since post #1 can be modified as time goes on, I think the engineering targets should be set first.
Compatibility- min impedance for ? 8/4/2ohm amplifiers, passive or active
Sensitivity/extrnsion, max continuous SPL- at ? listening distance
Aesthetic- ?large classic bookshelf with small stand, or floorstander, ? dimensions
Concept ie. Directivity- monopole, cardioid, dipole, and for what frequencies,
Choosing drivers and doing the XO is the “fun” part, but once you decide on concept and cabinets shape, the directivity is somewhat “baked-in” so it important to spend time on this step.
Compatibility- min impedance for ? 8/4/2ohm amplifiers, passive or active
Sensitivity/extrnsion, max continuous SPL- at ? listening distance
Aesthetic- ?large classic bookshelf with small stand, or floorstander, ? dimensions
Concept ie. Directivity- monopole, cardioid, dipole, and for what frequencies,
Choosing drivers and doing the XO is the “fun” part, but once you decide on concept and cabinets shape, the directivity is somewhat “baked-in” so it important to spend time on this step.
Last edited:
This simulation is derived by the OSMC concept. The total expense is about 1200 € for drivers and xo.
Drivers: FaitalPro 12RS430 / SBA Satori MD60N-6 / SBA SB 26STWGC-4
Drivers: FaitalPro 12RS430 / SBA Satori MD60N-6 / SBA SB 26STWGC-4
- same baffle, but the position of the drivers is slightly different for the domes
- 70L BR tuned @ 30Hz
- High sensitivity and easy load
- Tweeter with a WG
Midrange unit (high passed) does not need that much enclosure volume for itself and tweeter, woofer needs it desperately
though (Qts=0.37; Vas=85.6 lit). 🙂
If i sim, it doesn't, this is (from published specs a sim in 50L of the SB29
Remember that the goal was an F3 of 40hz, this is lower. VAS does not equal the requested box size, in reality, and depending on the alignment it will be different often.
And the mid and the tweeter does not need 15-20L inside volume, but you need to calculate for the walls inside also, and for bracing, what will be neeeded in such a large cabinet. And you need to count for the volume of the port also...
That's some wild off axis. What if you exchange the Satori with SB NBAC 5" or 6"?
Overall balance is quite good considering it's a 12" woofer crossed relatively high.
As to the nbac, the 8R version is not sensitive enough to reach the 90 dB goal of the original project while the 4R version could generate a low impedance.
@hifijim already used the nbac in one of his projects (with real measurements), so it's not useful replicate that one.
Last edited:
@shadowplay62
Have you considered XT25BG60?
and TangBand 75-1558sh
https://audioxpress.com/article/test-bench-tb-speaker-75-1558sh-high-end-home-audio-3-dome-midrange
c.f.
https://audioxpress.com/article/tes...me-midrange-from-the-sb-acoustics-satori-line
Have you considered XT25BG60?
and TangBand 75-1558sh
https://audioxpress.com/article/test-bench-tb-speaker-75-1558sh-high-end-home-audio-3-dome-midrange
c.f.
https://audioxpress.com/article/tes...me-midrange-from-the-sb-acoustics-satori-line
Last edited:
Andy has explained it in the opening post. It is not clear though if there is enough interested parties.
I guess a poll would give an answer to it.
What need to be different?
It need to be smaller, a lot cheaper and more like said above, a Warfdale Dovedale size cabinet, not a high end high power speaker. It need to be easy to build and good sounding. That was the original concept. A bit the econowave of the monkey coffin box, making a good and easy project on a budget/size restrictions with a big woofer, a mid cone and a dome tweeter like the orignal monkey coffin speakers of the past.
It need to be smaller, a lot cheaper and more like said above, a Warfdale Dovedale size cabinet, not a high end high power speaker. It need to be easy to build and good sounding. That was the original concept. A bit the econowave of the monkey coffin box, making a good and easy project on a budget/size restrictions with a big woofer, a mid cone and a dome tweeter like the orignal monkey coffin speakers of the past.
This is an interresting concept : the mid (here the very goodd NLA Peereless NE149W-04) is loaded in a tube making something between the open baffle with large acoustic shortcut and a short transmission line load. The 8 ohms is still at SoundImport.
https://www.speakerdesignworks.com/copy-of-anthologys-1
J Holtz/Curt Campbell having hard time to find a cheap alternative of this mid (SS Revelattor equivalent) chose the 5" NBAC to stay the kit cheap imho. The NBAC has good details and is not harsh, while it is certainly loose in punch perhaps VS the Peereless/Revelator.
The Dayton tweeter is NLA, I woulld change it as the nowadays Dayton is not as good.
Something like the 22/TAF G as the 5" NBAC can be happy around a 3 k hz cut off in a non horned but broad off axis.
Something funny coulld be the Silver Flute @profiguy talks about as a cheap good driver (mix of paper and glass fiber llike Wavecore (good but expensive : same price than SS Revelator mids)
A Wavecore horned 1.1" for the top could be something too : A13/14.
I personnaly also could be triggered by something like a Hivi Swan silicate magnesium mid à la Dynaudio. They were used in the totem Forest andd it sounded very fine ! (Ali ?)
For the 8" or 10", it coulld start from the Dayton RS225/265, but is expensive in Europe and taxes will explode soon making it a not wanted choice.
There are good candidates : SS Discovery, SB Acoustic 10" as already said (I would stay away from the 8" for bass at SB Acoustic), Faital 10".
Hors something à la Heissmann with a passive radiator for something funnier than a Ouistiti coffin.
https://www.speakerdesignworks.com/copy-of-anthologys-1
J Holtz/Curt Campbell having hard time to find a cheap alternative of this mid (SS Revelattor equivalent) chose the 5" NBAC to stay the kit cheap imho. The NBAC has good details and is not harsh, while it is certainly loose in punch perhaps VS the Peereless/Revelator.
The Dayton tweeter is NLA, I woulld change it as the nowadays Dayton is not as good.
Something like the 22/TAF G as the 5" NBAC can be happy around a 3 k hz cut off in a non horned but broad off axis.
Something funny coulld be the Silver Flute @profiguy talks about as a cheap good driver (mix of paper and glass fiber llike Wavecore (good but expensive : same price than SS Revelator mids)
A Wavecore horned 1.1" for the top could be something too : A13/14.
I personnaly also could be triggered by something like a Hivi Swan silicate magnesium mid à la Dynaudio. They were used in the totem Forest andd it sounded very fine ! (Ali ?)
For the 8" or 10", it coulld start from the Dayton RS225/265, but is expensive in Europe and taxes will explode soon making it a not wanted choice.
There are good candidates : SS Discovery, SB Acoustic 10" as already said (I would stay away from the 8" for bass at SB Acoustic), Faital 10".
Hors something à la Heissmann with a passive radiator for something funnier than a Ouistiti coffin.
Last edited:
If people are to get their teeth into a group design I'm not sure easy is necessarily an objective we want to pick up although I can see why it is an objective to consider. For example, I had assumed some fun iterating waveguide and crossover design to move the radiation pattern towards a nicely controlled narrowish one in contrast to the wider one typical of floor standing towers. If the speaker is to work vertically and horizontally that would involve a rotatable tweeter/mid half-baffle. Wide shallow cabinets tend to need a bit more thought w.r.t. being acoustically inert though a separate sub-chassis could help here.
Should the project have an objective of using design to gain technical performance with standard range drivers? This will inevitably introduce a degree of complexity though, obviously, not something that is beyond the average DIY speaker enthusiast. Or should it seek to be as simple as possible at the expense of some technical performance in order to minimize the build effort? I favour the former but it is something to discuss.
Should the project have an objective of using design to gain technical performance with standard range drivers? This will inevitably introduce a degree of complexity though, obviously, not something that is beyond the average DIY speaker enthusiast. Or should it seek to be as simple as possible at the expense of some technical performance in order to minimize the build effort? I favour the former but it is something to discuss.
First, list your needs : budget, room size and listenning distance, prefered laod or at list your F6/F10 bass needs according to you. What you come from today, type of amps/power, etc.
It is important as members said already. Sometimes a good Studio monitor can be cheaper (Behringer for instance and as good) or second hand market. The Linton is cheap and good too and iirc had good review at Erinscorner (pr was it the bigger brother ?)...
It is important as members said already. Sometimes a good Studio monitor can be cheaper (Behringer for instance and as good) or second hand market. The Linton is cheap and good too and iirc had good review at Erinscorner (pr was it the bigger brother ?)...
I find the driver arrangement interesting, with the dome and the tweeter receding towards the margin of the baffle (an not only towards the imaginary line defined by the margin of the woofer).Hmmmm, now where have I seen this before -
Oh, this looks quite like my speakers -
Untitled by A H, on Flickr
by A H, on Flickr
Closed box c.40L (old repurposed Akai SW125), WO24P-4 9.5" woofer, Morel EM1308 2.25" mid and Morel ET448 Tweeter. Currently DSP crossover but working on a passive one.
My preference would be for a closed box options around the 35-40L with F3 at 45-50hz, F10 less than 30hz (WO24P-4 just about does this so does the marginally cheaper SB29NRX-8). If the parts count (less woodwork) can be kept below £1000/$1250 for a pair then that would be good.
Is this the result of simulation? Does it aim to control directivity?
I have no intention for this kind f speakers, but high-efficiency large 3-way is sortof classic... No dome mid and preferably acoustic LR2 xos. BR ok for passive.
How about a poor man's Gravesen design? http://www.troelsgravesen.dk/Faital-12-430.htm
But of course mid between W and T! Tweeter could be some other dome or a ribbon/AMT. Xo with reasonable price category parts. Option for active 2/3-way too.
How about a poor man's Gravesen design? http://www.troelsgravesen.dk/Faital-12-430.htm
But of course mid between W and T! Tweeter could be some other dome or a ribbon/AMT. Xo with reasonable price category parts. Option for active 2/3-way too.
Last edited:
Not sure if post 1 is the live version of project tenets, but I don't think one should specify maximum currency limits per woofer/mid/tweeter. That's very limiting and prone to price changes depending on where one lives. If you look back at how OSMC documentation (pdf) is written, the principal tenets are very clear, but not micro-detailed. For example, it talks about how the box "should be easy to build for most people". It doesn't say "it should be 100 litres", etc.
For me, the only emergent tenet so far is that it's a cost-effective, high-performance 3-way using currently available drivers, and that's all...so far!
For me, the only emergent tenet so far is that it's a cost-effective, high-performance 3-way using currently available drivers, and that's all...so far!