Hi everyone!
It's been almost two years since I last built a speaker, and I'm getting the urge again.
[TLDR:
A more compact floorstander using an SB Acoustics SB15SFCR39 for bass in a vented enclosure, extending further down to the early 20hz with boundary/room loading. The B&C 5CXN44 in a sealed enclosure for mid and high.]
My current setup is really good (here), but a few aspects have me considering a change:
Size: The speakers are quite large.
Low-end Limitation: They only reach down to 35hz with boundary loading.
Horizontal Coverage: It's not as wide as I'd like.
Practicality: The horn on top is a bit of a concern, especially with baby GG² about to start walking.
As you can see below the measured 'anechoic' response yields quite a bit more low-end extension when in the listening position. I thought this would be fine but there has been the odd movie or song that lacks a little in the rumble department. Boundary loading really is my friend here (more on that later).
Shortly after building these I added Dirac and that improved things a lot over my manual room correction (manual not shown).
When I made my workshop speakers (here) I really enjoyed the sound of the B&C 5CXN44 coaxial drivers and found that they gave quite a nice wide image even when I am at the end of the sofa. I think this is because of the diffraction and tuning the response to work best slightly off axis due to the choppy response a 0 degrees.
SO...
An idea I have been chucking around in my head for a couple of weeks is this:
A more compact floorstander using an SB Acoustics SB15SFCR39 for bass in a vented enclosure, extending further down to the early 20hz with boundary/room loading. For mid and high, the B&C 5CXN44 in a sealed enclosure. Both drivers would share the floorstanding unit, reducing both physical and perceived space.
SB15SFCR39 ≈ 26L / 35hz vented
5CXN44 ≈ 4L sealed
I am totally up for other drivers but I don't want to go beyond 200mm wide baffle and I'm not too keen on a side mounted woofer owing to little fingers.
It's been almost two years since I last built a speaker, and I'm getting the urge again.
[TLDR:
A more compact floorstander using an SB Acoustics SB15SFCR39 for bass in a vented enclosure, extending further down to the early 20hz with boundary/room loading. The B&C 5CXN44 in a sealed enclosure for mid and high.]
My current setup is really good (here), but a few aspects have me considering a change:
Size: The speakers are quite large.
Low-end Limitation: They only reach down to 35hz with boundary loading.
Horizontal Coverage: It's not as wide as I'd like.
Practicality: The horn on top is a bit of a concern, especially with baby GG² about to start walking.
As you can see below the measured 'anechoic' response yields quite a bit more low-end extension when in the listening position. I thought this would be fine but there has been the odd movie or song that lacks a little in the rumble department. Boundary loading really is my friend here (more on that later).
Shortly after building these I added Dirac and that improved things a lot over my manual room correction (manual not shown).
When I made my workshop speakers (here) I really enjoyed the sound of the B&C 5CXN44 coaxial drivers and found that they gave quite a nice wide image even when I am at the end of the sofa. I think this is because of the diffraction and tuning the response to work best slightly off axis due to the choppy response a 0 degrees.
SO...
An idea I have been chucking around in my head for a couple of weeks is this:
A more compact floorstander using an SB Acoustics SB15SFCR39 for bass in a vented enclosure, extending further down to the early 20hz with boundary/room loading. For mid and high, the B&C 5CXN44 in a sealed enclosure. Both drivers would share the floorstanding unit, reducing both physical and perceived space.
SB15SFCR39 ≈ 26L / 35hz vented
5CXN44 ≈ 4L sealed
I am totally up for other drivers but I don't want to go beyond 200mm wide baffle and I'm not too keen on a side mounted woofer owing to little fingers.
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Since I have so much boundary/room gain I started thinking about what I could get out of another driver. So, I tried some fudged experiments.
I took the quasi anechoic measurement of my current system and divided it by the raw room measurement and got this repsonse which, I think, should show the rooms influence on the system:
It shows quite a boost from 80hz down and a spike at 50hz which is my room ringing
Looking at the SB SB15SFCR39 I can get a fairly low response with the following alignment. With the simulation together with the room influence you get about 15hz lower than the current system does:
26.5 L / 35hz
However, even at 1w the displacement of the woofer is pretty high.
I took the quasi anechoic measurement of my current system and divided it by the raw room measurement and got this repsonse which, I think, should show the rooms influence on the system:
It shows quite a boost from 80hz down and a spike at 50hz which is my room ringing
Looking at the SB SB15SFCR39 I can get a fairly low response with the following alignment. With the simulation together with the room influence you get about 15hz lower than the current system does:
26.5 L / 35hz
However, even at 1w the displacement of the woofer is pretty high.
Here is a quick mock-up of how I see the cabinet being laid out:
PS. imagine there is a vent on the same panelas the driver in the lower cabinet
PS. imagine there is a vent on the same panelas the driver in the lower cabinet
I've Thinking more about what I want to get out of this project and how I want to do it. One key aspect is time and not having as much of it since we gained a third family member. Therefore, using a driver I have used before helps and perhaps simplifying the bass element even more so might help too (for the better).
I have been looking at using two SB15SFCR39 in a sealed alignment that is pretty much the same volume as one vented.
As can be seen above the vented option unloads quite feverishly beneath tuning (at 2w) and although there won't be program material running in this area all the time I'd like to have some headroom.
Below is a dual driver sealed alighment Eq roughly to the same response but I can get around 10 watts before the EQ hits xmax. I will NEVER need this much SPL. My guess is it never exceeds 85db even on movie night.
And with my room influence applied I get quite a lot of fat to remove with room correction EQ. The unEQ'd sealed alighment is pretty close and woulnd't need much touching up in reality.
Hope this all makes sense.
I have been looking at using two SB15SFCR39 in a sealed alignment that is pretty much the same volume as one vented.
As can be seen above the vented option unloads quite feverishly beneath tuning (at 2w) and although there won't be program material running in this area all the time I'd like to have some headroom.
Below is a dual driver sealed alighment Eq roughly to the same response but I can get around 10 watts before the EQ hits xmax. I will NEVER need this much SPL. My guess is it never exceeds 85db even on movie night.
And with my room influence applied I get quite a lot of fat to remove with room correction EQ. The unEQ'd sealed alighment is pretty close and woulnd't need much touching up in reality.
Hope this all makes sense.
And for clarity here is the room. Speakers on one side and listening position against the other. Room is about 3.5m across.
OK. So, life (toddler) gets in the way. Bless, etc.
I noticed this little 4inch coax by Celestian and I like small things. It's very cute but the directivity graphs look a bit nuts. Looks like both the woofer and tweeter lose their respective directivity opposite each other at around 2.5k and would need a steep filter to keep this linear. The top end looks a bit choppy too.
For 70£ each they do sound like a bit of fun tho. Maybe they could work as a mid-tweeter along with a midwoofer crossing at 500hz+. Food for thought.
If anyone has any experience with this let me know 🙂
https://celestion.com/product/tfx0412/
TFX0412
I noticed this little 4inch coax by Celestian and I like small things. It's very cute but the directivity graphs look a bit nuts. Looks like both the woofer and tweeter lose their respective directivity opposite each other at around 2.5k and would need a steep filter to keep this linear. The top end looks a bit choppy too.
For 70£ each they do sound like a bit of fun tho. Maybe they could work as a mid-tweeter along with a midwoofer crossing at 500hz+. Food for thought.
If anyone has any experience with this let me know 🙂
https://celestion.com/product/tfx0412/
Most coaxials have pretty ragged response measurements (both on and off axis), so there are some trade-offs involved with using them. Luckily they typically don't sound as scary as they measure. It can take more tweaking to get them dialed in because it's not as obvious what's wrong when the frequency response is inherently uneven (and typically not consistently so when comparing on- and off-axis response).
It takes something like the KEF approach with a lot of finesse in the waveguides and transitions to make a co-ax that measures really well.
It takes something like the KEF approach with a lot of finesse in the waveguides and transitions to make a co-ax that measures really well.
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Several people have had good success with the Sica 5" coax, well documented on both this website and ASR. It's also reasonably priced.
@grahamgraham: Interesting speakers.
As I understand besides having the itch to new iteration of speaker, you would like:
a) wider dispersion?
b) lower/deeper bass?
Have you tried stacking the two 12" on one side? From you graphs I see room-null at around 160 hz. Just wondering if that would help on what you feel is missing. I guess with highish crossover you need to add inductor/6dB filter on lower woofer to have proper phase matching.
If that works, then 2*8" in 40-50 liters will properly be enough for you. Going up to 60 liters, you can play with 26W Discovery (2*10")
As I understand besides having the itch to new iteration of speaker, you would like:
a) wider dispersion?
b) lower/deeper bass?
Have you tried stacking the two 12" on one side? From you graphs I see room-null at around 160 hz. Just wondering if that would help on what you feel is missing. I guess with highish crossover you need to add inductor/6dB filter on lower woofer to have proper phase matching.
If that works, then 2*8" in 40-50 liters will properly be enough for you. Going up to 60 liters, you can play with 26W Discovery (2*10")
Thanks for all the input guys. The Sica does look interesting and quite cheap. I want to rule out going 4 way so would handle 100hz> nicely. Food for thought.
@rolytheman
Correct! Wider dispersion, deeper bass and smaller size. Basically, squeezing the engineering from all angles.
Yes, your idea of side mount woofers had occurred to me, I'd rather keep them at the rear because of small fingers but I could make a grille again.
200x250x900 is the max size and 160x200x900 is my goal.
As to wider dispersion, I want to keep with compression drivers but can't find any small horns that go wide.
@rolytheman
Correct! Wider dispersion, deeper bass and smaller size. Basically, squeezing the engineering from all angles.
Yes, your idea of side mount woofers had occurred to me, I'd rather keep them at the rear because of small fingers but I could make a grille again.
200x250x900 is the max size and 160x200x900 is my goal.
As to wider dispersion, I want to keep with compression drivers but can't find any small horns that go wide.
This development thread may interest you (current design has shifted to rear woofers). https://www.audiosciencereview.com/...active-floorstander-development-thread.49881/
Their already released speakers use the smaller Sica coax.
Their already released speakers use the smaller Sica coax.
So low frequency extension and keeping things simple and protected…..
Almost all recordings have the 100hz and below content mixed to mono during the mastering process….there is NO reason for stereo separation or elements here…….a single subwoofer is all that’s needed…..downfiring protects the driver and adds 3-5db of gain.
Almost all recordings have the 100hz and below content mixed to mono during the mastering process….there is NO reason for stereo separation or elements here…….a single subwoofer is all that’s needed…..downfiring protects the driver and adds 3-5db of gain.
I suggest closed boxes for the woofers, you can let them play to 200-300Hz as stereo and room response goes easily to 25-30Hz.
You will need dsp anyway to make room response reasonable... coaxials can be very difficult with passive xo too. So 3 channel dsp and amps, Hypes FA is recommended
You will need dsp anyway to make room response reasonable... coaxials can be very difficult with passive xo too. So 3 channel dsp and amps, Hypes FA is recommended
I meant you can try two front firing woofers.
Personally I would rather have wide and not so deep speaker than narrow and deep.
You may want to invert this idea; keep one woofer and (nearly) double the volume.
I've used this woofer in 23L sealed and 41.5L vented (Fb at 35Hz).
In the sealed alignment they were okay, but the vented enclosure was pretty amazing digging down to subwoofer territory. If it turned out to be too much for your room you can always seal off the ports. The measurement below were taken outside.
The war on space is over. It started with a couple of stuffed toys - innocuous enough. Then came the wooden fruits, the books, the blocks, the tiles. Then one day a scale kitchen takes claim of your front room and we lost the war on space. Child wins.
Anyway, my point is, I suppose... my priorities have changed so I need to think smaller and therefore, bigger.
As mentioned above, I am aiming for a floorstander around 160mm wide, depth not so much as issue but 180mm max.
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I noticed a horn on a UK speaker website a while ago and it was dirt cheap. Lunch money cheap so I gave it a go and below are the measurements of it with my Peerless DFM-2535R00-08 mounted. This could help me achieve my narrow width but I'd have to choose woofer(s) carefully. Maybe an MMT.
160x120x60mm deep. Quite small. I won't share where it comes from but if you want to know DM me and I'll tell you why I'm not. Not bad performance but it is very cheaply made and looks a bit ugly.
Anyway, my point is, I suppose... my priorities have changed so I need to think smaller and therefore, bigger.
As mentioned above, I am aiming for a floorstander around 160mm wide, depth not so much as issue but 180mm max.
--------------------------
I noticed a horn on a UK speaker website a while ago and it was dirt cheap. Lunch money cheap so I gave it a go and below are the measurements of it with my Peerless DFM-2535R00-08 mounted. This could help me achieve my narrow width but I'd have to choose woofer(s) carefully. Maybe an MMT.
160x120x60mm deep. Quite small. I won't share where it comes from but if you want to know DM me and I'll tell you why I'm not. Not bad performance but it is very cheaply made and looks a bit ugly.
For the past few days I have been listening to my Genelec 4020c speakers to cleanse my pallet before a new build. I really like these speakers but find the top end a littl bit forward. I don't know if this is the aluminium tweeter, the amp or just the FR. In any event, I usually apply a high shelf starting at 1500hz -1.5db.
The directivity of these speakers in interesting. They dog-leg at about 2k and from there upwards have pretty good constant directivity.
Usually I'd think that indicated a shallow crossover from woofer to horn at about 1.5k but the crossover on these is 3k. How is the woofer so directional when it is only a 4" driver? Voodoo cabinet geometry, perhaps.
With in room response taken in 3 possible listening positions and averaged (with and without light correction). The boundary gain I use really helps it's bottom end in comparison to the datasheet.
I would like to replicate the Genelecs but a bit lower.
The directivity of these speakers in interesting. They dog-leg at about 2k and from there upwards have pretty good constant directivity.
Usually I'd think that indicated a shallow crossover from woofer to horn at about 1.5k but the crossover on these is 3k. How is the woofer so directional when it is only a 4" driver? Voodoo cabinet geometry, perhaps.
With in room response taken in 3 possible listening positions and averaged (with and without light correction). The boundary gain I use really helps it's bottom end in comparison to the datasheet.
I would like to replicate the Genelecs but a bit lower.