Introduction: I've built 6 speaker projects before, but it was in the years before 2004 when the hobby was booming. After a long break my ears are older but my brain is still fresh. I'm keen to build something with good performance and compact size that fits into my current lifestyle. These days I require less SPL than in the past. I will use Soundeasy for the design and I have a calibrated measurement microphone. Proposed project specs as follows.
Dimensions: Floorstanding, approx. 93cm x 21cm x 28cm (HxWxD)
Driver Layout: W-M-T
Bass enclosure: 20 to 25 Litre. Ported enclosure.
Bass driver: 7" Woofer.
Midrange driver: 5" Woofer / Midrange.
Tweeter: 3/4" Fabric dome.
W-M crossover: 2nd order LR acoustic at around 500~700Hz.
M-T crossover: 4th order LR acoustic at around 3.0kHz.
Proposed driver selection:
Woofer: Seas ER18RNX (88.5dB)
Midrange: Seas CA15RLY (87.5dB)
Tweeter: Seas 22TFF (91dB) OR Scanspeak D2008/8512 (88dB)
Questions:
1) What is the best ported enclose size for Seas ER18RNX Woofer?
2) Would it be better to use a Scanspeak 18W series woofers such as the sliced-cone 18W/8531G00 revelator in this project with a 25 Litre enclosure?
3) Will the CA15RLY work well in a small sealed enclose with the intended 500~700Hz high-pass passive filter?
4) Can you think of a better driver to use as a midrange that has smooth response? It must not use foam surround since I want to keep them for the next 30 years.
5) If you have experience with the 22TFF tweeters, could you please comment about their suitability. I used the Scanspeak D2008/8512 before, and I'm seriously thinking to buy another pair for this project.
All comments are welcome. Thanks for reading!
Dimensions: Floorstanding, approx. 93cm x 21cm x 28cm (HxWxD)
Driver Layout: W-M-T
Bass enclosure: 20 to 25 Litre. Ported enclosure.
Bass driver: 7" Woofer.
Midrange driver: 5" Woofer / Midrange.
Tweeter: 3/4" Fabric dome.
W-M crossover: 2nd order LR acoustic at around 500~700Hz.
M-T crossover: 4th order LR acoustic at around 3.0kHz.
Proposed driver selection:
Woofer: Seas ER18RNX (88.5dB)
Midrange: Seas CA15RLY (87.5dB)
Tweeter: Seas 22TFF (91dB) OR Scanspeak D2008/8512 (88dB)
Questions:
1) What is the best ported enclose size for Seas ER18RNX Woofer?
2) Would it be better to use a Scanspeak 18W series woofers such as the sliced-cone 18W/8531G00 revelator in this project with a 25 Litre enclosure?
3) Will the CA15RLY work well in a small sealed enclose with the intended 500~700Hz high-pass passive filter?
4) Can you think of a better driver to use as a midrange that has smooth response? It must not use foam surround since I want to keep them for the next 30 years.
5) If you have experience with the 22TFF tweeters, could you please comment about their suitability. I used the Scanspeak D2008/8512 before, and I'm seriously thinking to buy another pair for this project.
All comments are welcome. Thanks for reading!
Last edited:
A quick calc using this HiFi Loudspeaker Design
ER18RNX, 18.24l, f3 47hz, port 5cm diam 12.8cm long
18W/8531, 46.5l, f3 31hz, port 5cm diam 10.36cm long
18W/8531, 20l, f3 48hz, port 5cm diam 15.3cm long
In 20l I have modelled the Dayton ES180TiA and this shows -
ES180TiA, 20l, f3 34hz, port 5cm diam, 21.7cm long.
You can use this calculator to give you a quick check then model with full response modellers.
ER18RNX, 18.24l, f3 47hz, port 5cm diam 12.8cm long
18W/8531, 46.5l, f3 31hz, port 5cm diam 10.36cm long
18W/8531, 20l, f3 48hz, port 5cm diam 15.3cm long
In 20l I have modelled the Dayton ES180TiA and this shows -
ES180TiA, 20l, f3 34hz, port 5cm diam, 21.7cm long.
You can use this calculator to give you a quick check then model with full response modellers.
One tip is to have the port tube easily accessible so you can change the length. Theory doesn't always work 'in room' and you may need some fine tuning.
My SEAS L18 three way is 85cm x 20cm x 22cm and the port (5cm) ended up being 23cm to give the flattest bass response in room. This was a considerable increase in what I had calculated. The port is located in the bottom of the cabinet.
My SEAS L18 three way is 85cm x 20cm x 22cm and the port (5cm) ended up being 23cm to give the flattest bass response in room. This was a considerable increase in what I had calculated. The port is located in the bottom of the cabinet.
Attachments
+1 for the ES180TiA (note: this is different to the older ES180Ti driver)
For mid duties you might consider a dome, eg RS52AN-8 2" Dome Midrange 8 Ohm Specification Sheet
I use these drivers with a Scanspeak R2904/7000000 tweeter and active xo miniDSP in similar size cabinets.
For mid duties you might consider a dome, eg RS52AN-8 2" Dome Midrange 8 Ohm Specification Sheet
I use these drivers with a Scanspeak R2904/7000000 tweeter and active xo miniDSP in similar size cabinets.
Attachments
Any more info on these speakers please, looking at a similar set up with twin ES180TiA in 40l with small mid (looked at the Morel EM1308 but liking the Scanspeak 10F8424). Also likely to go minidsp. Be interested to hear you views on how the woofers sound.
If you don’t want to clutter up this thread please reply here Project Idea - comments please
My design uses the EM1308. I also have the RS52ANs. After doing many listening comparisons the 52s are back in their box and that's where they will remain
Was there much in it between the 52's and the 1308's in the end?
Yes. The EM1308 had a far more natural tonal quality. Especially noticable on acoustic guitar where the 52s never lost a 'steely', 'hollow' quality, whereas the EM1308 had some of the most life-like reproduction I've heard.
The 52s can be detailed and dynamic but ultimately imparted their own sonic signature to everything.
If I'm going to change to 18W8535G00, its not a big compromise to increase the bass enclosure volume to around 34~35 litres. I'd probably end up with external Dimensions of 95cm x 22cm x 32cm. Using 25mm MDF material I'd get 41 litres total, but I have to subtract a few litres for internal bracing, mid enclosure, driver volume, crossover etc.
Hi,
there is a couple of things one could improve on the speaker concept presented. The first would be to increase the woofer size to an 8" unit (while at the same time keeping the speaker measures about the same or close to original ones), the second to reduce the panel thickness to 3/4" and at the same time reduce the weight and increase the internal volume needed for the woofer. ER18RNX unit will probably prove to have a higher Fs than specified which is quite a common affair in a diy world, further compromising the low end response, obviously depending on one's own habits and expectations. The third potential improvement could be deploying a 2" dome midrange, favoring a higher mid/high xo frequency and still be in the zone of a good power response, rendering good sound quality.
Visaton should not be lost out of sight if one is searching a good quality dome midrange, fabric and titan are available.
Traditionally, Morel is offering good domes and a novelty TM 4055-8, not aesthetically optimal complement to a woofer driver though.
there is a couple of things one could improve on the speaker concept presented. The first would be to increase the woofer size to an 8" unit (while at the same time keeping the speaker measures about the same or close to original ones), the second to reduce the panel thickness to 3/4" and at the same time reduce the weight and increase the internal volume needed for the woofer. ER18RNX unit will probably prove to have a higher Fs than specified which is quite a common affair in a diy world, further compromising the low end response, obviously depending on one's own habits and expectations. The third potential improvement could be deploying a 2" dome midrange, favoring a higher mid/high xo frequency and still be in the zone of a good power response, rendering good sound quality.
Visaton should not be lost out of sight if one is searching a good quality dome midrange, fabric and titan are available.
Traditionally, Morel is offering good domes and a novelty TM 4055-8, not aesthetically optimal complement to a woofer driver though.
Then there's the sb dome mid which is probably ages away.
SB Acoustics Official Account (@sbacoustics) • Instagram photos and videos
SB Acoustics Official Account (@sbacoustics) • Instagram photos and videos
The Scanspeak 18W/8531G00 is a bit of a luxury item considering my needs. However I would rather over-engineer than have something that falls short. Because of the lower sensitivity of 18W/8531G00 (87db/2.83V) I'm going to drop down to a 4" size mid driver. I never used a dome midrange before, and I prefer a conventional driver as a more rugged and reliable option. Currently I'm looking at the following 4" drivers to use as a midrange:
Seas CA12RCY (86db/2.83V)
Seas W12CY003 (85.5dB/2.83V)
SB Acoustic SB12NRX25-08 (85.5dB/2.83V)
I'm a bit partial to European made products, so I don't know if I am ready to pair a SB Acoustic midbass driver in between a Scanspeak Revelator Woofer and D2008/8512 tweeter. I am thinking the nice response curve of the Seas W12CY003 would make the crossover design relatively straight-forward.
Seas CA12RCY (86db/2.83V)
Seas W12CY003 (85.5dB/2.83V)
SB Acoustic SB12NRX25-08 (85.5dB/2.83V)
I'm a bit partial to European made products, so I don't know if I am ready to pair a SB Acoustic midbass driver in between a Scanspeak Revelator Woofer and D2008/8512 tweeter. I am thinking the nice response curve of the Seas W12CY003 would make the crossover design relatively straight-forward.
I remember seeing W12 Nextel measurements, and there was some problem ~1kHz, FR was not as flat as in datasheet, and distortion was quite high.
Here are some drivers suggestions, I have experience with some of them. Small flange tweeter allows shorter CtC. Crossovers 700-1000 and 3000-4000.
Woofer:
18W/4531
MW19P-4
Wavecor WF182BD09/10
W18 Magnesium
Midrange:
10F
MR13P
NE123W
12M (crossover around 1kHz)
W12 Magnesium (crossed at 2kHz)
Tweeter:
D3004/6020
D2004/6020
SB26STCN
Seas DXT (in combination with W12)
Here are some drivers suggestions, I have experience with some of them. Small flange tweeter allows shorter CtC. Crossovers 700-1000 and 3000-4000.
Woofer:
18W/4531
MW19P-4
Wavecor WF182BD09/10
W18 Magnesium
Midrange:
10F
MR13P
NE123W
12M (crossover around 1kHz)
W12 Magnesium (crossed at 2kHz)
Tweeter:
D3004/6020
D2004/6020
SB26STCN
Seas DXT (in combination with W12)
I measured 10F in prototype cabinet with 22W and D2004, see results here:
hififorum.sk • Zobrazit tema - Ze zvedavosti - regalove tripasmo 8+3+0.75 Scan Speak
It was not finished, I had too many projects running in parallel. If I were doing it again, I would have used tilted baffle to allow for LR2.
18W revelator I know from Ekta Grande. Whether to go with 4Ohm or 8Ohm it depends on your amplifier capability. Generally I prefer 4Ohm woofers to achieve higher sensitivity. Both 10F versions should be fine. Check Hificompass for their measurements.
MR13P and WF182 measurements here:
SatWaveSS :: Pkaudio
MW19P + MR13P would make nice small floorstander, 30l BR for woofer, ~5l for mid.
hififorum.sk • Zobrazit tema - Ze zvedavosti - regalove tripasmo 8+3+0.75 Scan Speak
It was not finished, I had too many projects running in parallel. If I were doing it again, I would have used tilted baffle to allow for LR2.
18W revelator I know from Ekta Grande. Whether to go with 4Ohm or 8Ohm it depends on your amplifier capability. Generally I prefer 4Ohm woofers to achieve higher sensitivity. Both 10F versions should be fine. Check Hificompass for their measurements.
MR13P and WF182 measurements here:
SatWaveSS :: Pkaudio
MW19P + MR13P would make nice small floorstander, 30l BR for woofer, ~5l for mid.
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If you want to use the SEAS excel drivers for a midrange then you really want to the W12CY001.
Gornir has a small 2 way with it here that shows you how to get the most from it with regards to crossover points and slopes etc.
www.audioexcite.com >> Excellence Two – M1 DXT
SEAS manesium excel drivers typically have much lower distortion and flatter frequency responses within their useful operating range. Yeah they have horrible breakup, but if you cross low enough then it's not a problem. With the W12 and W15 this only requires a crossover around 2khz, which most tweeters are more than comfortable with. The DXT happens to be a very good tweeter too.
SB acoustics may be based in Indonesia but the engineering prowess comes from what once was Danish Sound Technology. Their drivers are some of the best in the world and come at prices significantly lower than the typical fair from Europe. This, I believe, isn't actually because of production costs in Indonesia but more SB are charging a price that's more reflective of what went into the driver you are buying. Scanspeak and SEAS, especially with SEAS new Graphene series, just charge what they can rather than what the drivers are actually worth.
As above the MW19P + MR13P + suitable tweeter would make for a very nice small floor stander.
You could just omit the mid range entirely and build one of the Pharaoh designs here.
2х полосные проекты | HiFiCompass
You'd need to extend the cabinet down and reoptimise the bass alignment though.
If you want to go small three way then I'd use the
MW19P, W12CY001 and 27TBCD/GB-DXT.
These are easy to obtain and are largely satisfy your European preference. However if I wanted to optimise this design even further I would be foolish to ignore other drivers from non European places.
The W6-1139SIF from TB drivers would be a killer bass driver. This optimises into a smallish ported box and gives you a lot of bass if tuned appropriately. You may need passive radiators though, instead of ports.
It is insensitive, like seriously insensitive, but what you gain from this is the requirement for a small box and deep bass. To me this sounds exactly what the application demands. It will not crossover high, so think 200Hz maximum.
This isn't an issue for tons of 4" mid/bass drivers used as midranges. Heck, even the little scanspeak 10F would be reasonably okay with this, it wouldn't break with a 2nd order at 200Hz, even though it's distortion wouldn't be optimally low when pushed.
As far as midrange drivers go Etons 3-400/A8/25Mg is one of the best drivers for covering 200-3kHz. Although they are discontinued and never got much press even when they were around. Eton's drivers are usually a bit of a miss, but this one measured fantastically, it's a shame I never had a chance (the need) to use it.
As an alternative I would simply go with the W12CY001, a ZA14 would also work but it has a bigger chassis. You can buy them from Hifi compass though.
If I wanted to go for a soft-cone then the MW13P would be my choice for this design. The MR13 has higher sensitivity but the MW will have lower distortion down low and give you more flexibility with an xover around 200Hz. I'd then use the DXT tweeter. Or an XT25.
The metal cones require a low xover point of around 2kHz but even if I was using the MW13 I would still cross around 2kHz to widen the vertical off listening axis.
I like the idea of using the W6-1139SIF because it gives a lot of extension in a cabinet smaller than the others and really pushes the idea of compact low SPL three way in the direction that it should go. Pretty much every bass driver recommended here is a standard 2 way orientated mid/bass or similar. This isn't optimising the design around giving you lots of bass extension and trading SPL and size for it.
Bass is always where the line is drawn when it comes to speaker design when cabinet size is being determined because the two are so inexplicably linked. You can literally go with any tweeter or any (within reason) midrange driver, the crossover will handle that, but when you have limited space you're automatically thrown into a battle of how loud vs how low. You don't care about how loud, so you better choose how low and find a driver that will maximise bass extension at the cost of SPL, otherwise it's just another 6-7" mid/bass in a floor standing box.
Sadly there aren't a huge number of sub drivers that are good for this.
I'd optimise it something like this...
Then there's the D165 from Reckhorn. These are inexpensive but look as if they are built like a tank. Reckhorn are German by the way if that helps
shop.reckhorn.net - All components are of high quality without compromise.
They also have a passive radiator you can use with them, so if that's needed it's available.
They optimise into giving you a pretty standard EBS alignment.
With both the TB and the Reckhorn you can go with smaller cabinets and more 'maximally flat' alignements. These give you less extension but no 'premature' roll off towards the mid 20s on the Hz scale. So you pick how you want to tune your cabinet and build it with regards to size.
Gornir has a small 2 way with it here that shows you how to get the most from it with regards to crossover points and slopes etc.
www.audioexcite.com >> Excellence Two – M1 DXT
SEAS manesium excel drivers typically have much lower distortion and flatter frequency responses within their useful operating range. Yeah they have horrible breakup, but if you cross low enough then it's not a problem. With the W12 and W15 this only requires a crossover around 2khz, which most tweeters are more than comfortable with. The DXT happens to be a very good tweeter too.
SB acoustics may be based in Indonesia but the engineering prowess comes from what once was Danish Sound Technology. Their drivers are some of the best in the world and come at prices significantly lower than the typical fair from Europe. This, I believe, isn't actually because of production costs in Indonesia but more SB are charging a price that's more reflective of what went into the driver you are buying. Scanspeak and SEAS, especially with SEAS new Graphene series, just charge what they can rather than what the drivers are actually worth.
As above the MW19P + MR13P + suitable tweeter would make for a very nice small floor stander.
You could just omit the mid range entirely and build one of the Pharaoh designs here.
2х полосные проекты | HiFiCompass
You'd need to extend the cabinet down and reoptimise the bass alignment though.
If you want to go small three way then I'd use the
MW19P, W12CY001 and 27TBCD/GB-DXT.
These are easy to obtain and are largely satisfy your European preference. However if I wanted to optimise this design even further I would be foolish to ignore other drivers from non European places.
The W6-1139SIF from TB drivers would be a killer bass driver. This optimises into a smallish ported box and gives you a lot of bass if tuned appropriately. You may need passive radiators though, instead of ports.
It is insensitive, like seriously insensitive, but what you gain from this is the requirement for a small box and deep bass. To me this sounds exactly what the application demands. It will not crossover high, so think 200Hz maximum.
This isn't an issue for tons of 4" mid/bass drivers used as midranges. Heck, even the little scanspeak 10F would be reasonably okay with this, it wouldn't break with a 2nd order at 200Hz, even though it's distortion wouldn't be optimally low when pushed.
As far as midrange drivers go Etons 3-400/A8/25Mg is one of the best drivers for covering 200-3kHz. Although they are discontinued and never got much press even when they were around. Eton's drivers are usually a bit of a miss, but this one measured fantastically, it's a shame I never had a chance (the need) to use it.
As an alternative I would simply go with the W12CY001, a ZA14 would also work but it has a bigger chassis. You can buy them from Hifi compass though.
If I wanted to go for a soft-cone then the MW13P would be my choice for this design. The MR13 has higher sensitivity but the MW will have lower distortion down low and give you more flexibility with an xover around 200Hz. I'd then use the DXT tweeter. Or an XT25.
The metal cones require a low xover point of around 2kHz but even if I was using the MW13 I would still cross around 2kHz to widen the vertical off listening axis.
I like the idea of using the W6-1139SIF because it gives a lot of extension in a cabinet smaller than the others and really pushes the idea of compact low SPL three way in the direction that it should go. Pretty much every bass driver recommended here is a standard 2 way orientated mid/bass or similar. This isn't optimising the design around giving you lots of bass extension and trading SPL and size for it.
Bass is always where the line is drawn when it comes to speaker design when cabinet size is being determined because the two are so inexplicably linked. You can literally go with any tweeter or any (within reason) midrange driver, the crossover will handle that, but when you have limited space you're automatically thrown into a battle of how loud vs how low. You don't care about how loud, so you better choose how low and find a driver that will maximise bass extension at the cost of SPL, otherwise it's just another 6-7" mid/bass in a floor standing box.
Sadly there aren't a huge number of sub drivers that are good for this.
I'd optimise it something like this...
Then there's the D165 from Reckhorn. These are inexpensive but look as if they are built like a tank. Reckhorn are German by the way if that helps
shop.reckhorn.net - All components are of high quality without compromise.
They also have a passive radiator you can use with them, so if that's needed it's available.
They optimise into giving you a pretty standard EBS alignment.
With both the TB and the Reckhorn you can go with smaller cabinets and more 'maximally flat' alignements. These give you less extension but no 'premature' roll off towards the mid 20s on the Hz scale. So you pick how you want to tune your cabinet and build it with regards to size.
Attachments
5th element, Thanks for your very detailed post.
I can see the points you have made, especially about low distortion of the Seas Excel magnesium cones. After searching a lot of websites I can see the Seas driver is likely to have 6db~10dB less 2nd+3rd harmonic distortion than the Scanspeak 10F/8424G00. Probably a much bigger difference in intermodulation products if my high pass filter is letting too much bass though. However I'm not going to settle on the W12CY001 partly because its sensitivity is only 84db/2.83V. I'm worried by the time I include a complicated band-pass filter I will actually drop voltage across the filter and be running out of SPL on the midrange driver. I also need to crossover at 3kHz with LR4 slopes, so I would need a RL trap for the cone resonance.
Right now I'm probably looking at the Scanspeak 18W/8431G00 Bass driver (8 ohm). I'm reluctant to pay almost the same amount for a Satori branded driver, unless there is a clear advantage. I admit I haven't studied distortion plots yet.
I was interested in your comments about Eton. Do you know if the Eton 4-212/C8/25 would retain similar advantage to their no obsolete midrange? I feel a bit suspicious there could be some nasty cone breakup mode that doesn't appear on the data sheet. I found some other carbon fibre drivers had that in the past.
Another driver I overlooked for some reason was the Seas MCA12RC. It has a larger surface area than the Scanspeak 10F, so that can help distortion. Its 86dB/2.83V is probably ideal to combine with the 18W/8431G00. It looks like it should do the same or better job than the Scanspeak 10F. Please let me know what you think.
I can see the points you have made, especially about low distortion of the Seas Excel magnesium cones. After searching a lot of websites I can see the Seas driver is likely to have 6db~10dB less 2nd+3rd harmonic distortion than the Scanspeak 10F/8424G00. Probably a much bigger difference in intermodulation products if my high pass filter is letting too much bass though. However I'm not going to settle on the W12CY001 partly because its sensitivity is only 84db/2.83V. I'm worried by the time I include a complicated band-pass filter I will actually drop voltage across the filter and be running out of SPL on the midrange driver. I also need to crossover at 3kHz with LR4 slopes, so I would need a RL trap for the cone resonance.
Right now I'm probably looking at the Scanspeak 18W/8431G00 Bass driver (8 ohm). I'm reluctant to pay almost the same amount for a Satori branded driver, unless there is a clear advantage. I admit I haven't studied distortion plots yet.
I was interested in your comments about Eton. Do you know if the Eton 4-212/C8/25 would retain similar advantage to their no obsolete midrange? I feel a bit suspicious there could be some nasty cone breakup mode that doesn't appear on the data sheet. I found some other carbon fibre drivers had that in the past.
Another driver I overlooked for some reason was the Seas MCA12RC. It has a larger surface area than the Scanspeak 10F, so that can help distortion. Its 86dB/2.83V is probably ideal to combine with the 18W/8431G00. It looks like it should do the same or better job than the Scanspeak 10F. Please let me know what you think.
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