3D printed sphere speakers with Sica 5.5" coax drivers

[ppataki]

I have performed all the DSP settings (pre-EQ, Dirac, post-EQ)

Here is how it sounds:

New video · Wednesday, Jul 9, 2025

Tap to view!

photos.app.goo.gl

Personally, I am amazed! I can just repeat myself:
- speakers totally disappear (probably due to the sphere shape + the flush mounting + the point-source nature of coax drivers)
- very 'live' sound, almost as with full range speakers
- detailed, airy treble
- vocals don't sound thin
- sound stage is extremely wide (esp. compared to my CHN110 & MAOP in similar sphere cabinets)

At least from my perspective I can safely say that (if size permits) I will only print my DIY speakers from now on

Now I will go ahead and start printing the rear speakers using the same Sica drivers but this time using a passive crossover
I will not put these in the spheres but will use them as external crossovers and for that I have printed a nice little case for them:

So I will continue this thread with this next part of this project
Stay tuned!

 

[JohnnyNG]

I have performed all the DSP settings (pre-EQ, Dirac, post-EQ)

Here is how it sounds:

New video · Wednesday, Jul 9, 2025

Tap to view!

photos.app.goo.gl

Personally, I am amazed! I can just repeat myself:
- speakers totally disappear (probably due to the sphere shape + the flush mounting + the point-source nature of coax drivers)
- very 'live' sound, almost as with full range speakers
- detailed, airy treble
- vocals don't sound thin
- sound stage is extremely wide (esp. compared to my CHN110 & MAOP in similar sphere cabinets)

At least from my perspective I can safely say that (if size permits) I will only print my DIY speakers from now on

Now I will go ahead and start printing the rear speakers using the same Sica drivers but this time using a passive crossover
I will not put these in the spheres but will use them as external crossovers and for that I have printed a nice little case for them:

View attachment 462677
View attachment 462678
View attachment 462679
View attachment 462680

So I will continue this thread with this next part of this project
Stay tuned!

Hey there - any progress with the passive version? Intrigued by this driver.

 

[ppataki]

Hey there - any progress with the passive version? Intrigued by this driver.

Yes, I just finished that a few days ago

Printing of the two additional spheres:

Mounting the rear right:
This was super easy as there is a shelf where I could put the box of the passive crossover and it is literally not visible that way

Mounting the rear left:

This looks less 'clean' as I had to fix the crossover box next to the sphere on the wall + there are the cables....

If anybody can recommend any better-looking way to make this happen, I am all ears (I was thinking about using white cable sheets which might ameliorate the looks a bit)

Frequency + phase response in the MLP using Psy smoothing:

That huge peak at 120Hz must be attributed to the corner placement of the speakers

The passive crossover has the crossover point at 2800Hz using 18/12 dB/oct. slopes
If we observe that area, there is no dip in the FR and the phase curve is relatively flat too so I think the crossover is well designed but I am happy to stand corrected here
F6 is 40Hz which is enough for me for rear speaker usage

The elevated highs are 'normal', I experienced the same when I was doing the active crossover settings. However I managed to tame that a little bit with volume and crossover settings (you can see that in post #2 earlier)

Based on all the above, I can strongly recommend the passive crossover version too! (I paid 90 EUR for the pair - extremely fair price IMHO)

 

[voodooless]

So, this is just the standard crossover that is in the datasheet? I’m asking because I may do something with the larger sibling and it also features a passive crossover in the datasheet. Would save an active channel Not a bad result regardless!

As to the crossover box: try to cram it into the sphere? Maybe without the PCB?

 

[JohnnyNG]

Yes, I just finished that a few days ago

Printing of the two additional spheres:
View attachment 467689

Mounting the rear right:
This was super easy as there is a shelf where I could put the box of the passive crossover and it is literally not visible that way

View attachment 467690

Mounting the rear left:

This looks less 'clean' as I had to fix the crossover box next to the sphere on the wall + there are the cables....

View attachment 467691

View attachment 467692

If anybody can recommend any better-looking way to make this happen, I am all ears (I was thinking about using white cable sheets which might ameliorate the looks a bit)

Frequency + phase response in the MLP using Psy smoothing:

View attachment 467693

That huge peak at 120Hz must be attributed to the corner placement of the speakers

The passive crossover has the crossover point at 2800Hz using 18/12 dB/oct. slopes
If we observe that area, there is no dip in the FR and the phase curve is relatively flat too so I think the crossover is well designed but I am happy to stand corrected here
F6 is 40Hz which is enough for me for rear speaker usage

The elevated highs are 'normal', I experienced the same when I was doing the active crossover settings. However I managed to tame that a little bit with volume and crossover settings (you can see that in post #2 earlier)

Based on all the above, I can strongly recommend the passive crossover version too! (I paid 90 EUR for the pair - extremely fair price IMHO)

Looks great! Glad the passive works well, makes things a bit easier. Now if I could just get them to the US...

 

[ppataki]

So, this is just the standard crossover that is in the datasheet? I’m asking because I may do something with the larger sibling and it also features a passive crossover in the datasheet. Would save an active channel Not a bad result regardless!

As to the crossover box: try to cram it into the sphere? Maybe without the PCB?

Yes it is

This is what they have in the manual:

And this is the crossover I used:

From here: https://www.bsacoustic.com/hifi-crossovers/cn-55c15cp-bs-acoustic-crossover-for-sica/
You can get the 6.5" crossover unit from them too

I definitely cannot cram it into the cabinet, it is really small already
I guess it will stay like this (it is OK)

 

[JohnnyNG]

Yes it is

This is what they have in the manual:

View attachment 467743

And this is the crossover I used:

View attachment 467744

From here: https://www.bsacoustic.com/hifi-crossovers/cn-55c15cp-bs-acoustic-crossover-for-sica/
You can get the 6.5" crossover unit from them too

I definitely cannot cram it into the cabinet, it is really small already
I guess it will stay like this (it is OK)

Is the pictured crossover one that SICA makes themselves? And yours is made by BSAcoustic?

 

[ppataki]

Is the pictured crossover one that SICA makes themselves? And yours is made by BSAcoustic?

The picture above is from the Sica manual
Mine is made by BS Acoustic (Slovakia)
(also see post #21 for pictures)

 

[Curvature]

Are you able to make impedance sweeps?

 

[ppataki]

Are you able to make impedance sweeps?

Unfortunately no

 

[Zinda]

Have you checked in simulations of port position on the sphere will affect anything. Since you can't physically aim it forward (directly), is there a chance of making it curve from a rear facing output to run along the outside forming a second wall that disperses the port back to the front and become part of your lower adaptor piece?
Just a thought to complicate things further.

 

[Dr Morbius]

wow. Impressive. The members continue to amaze me with their skills. Very cool.

I am totally in agreement with you, absolutely amazing!

 

[ppataki]

Have you checked in simulations of port position on the sphere will affect anything. Since you can't physically aim it forward (directly), is there a chance of making it curve from a rear facing output to run along the outside forming a second wall that disperses the port back to the front and become part of your lower adaptor piece?
Just a thought to complicate things further.

That is indeed a very creative idea, thank you!
To be very honest, I guess I will not have time to do it, due to my next project
And even before that, I will be moving to another apartment later this year (due to a divorce that has nothing to do with my hobby - just wanted to be clear about that ) so I will be happy if the above mentioned project could come to life this year itself

 

[Dumu]

You could hide the cross-over boxes somewhere else and run two pairs of speaker wires to the wall? Could even use a cable with 4 wires instead of 2x2 to minimize the visibility.

 

[JohnnyNG]

If I could 3D-print a nice box like that I'd show it off as well.

 

[somebodyelse]

You could hide the cross-over boxes somewhere else and run two pairs of speaker wires to the wall? Could even use a cable with 4 wires instead of 2x2 to minimize the visibility.

Speakons are good for that - 4 pole would do for this, but there are 8 pole versions as well.

 

[JohnnyNG]

So, this is just the standard crossover that is in the datasheet? I’m asking because I may do something with the larger sibling and it also features a passive crossover in the datasheet. Would save an active channel Not a bad result regardless!

As to the crossover box: try to cram it into the sphere? Maybe without the PCB?

Yes it is

This is what they have in the manual:

View attachment 467743

And this is the crossover I used:

View attachment 467744

From here: https://www.bsacoustic.com/hifi-crossovers/cn-55c15cp-bs-acoustic-crossover-for-sica/
You can get the 6.5" crossover unit from them too

I definitely cannot cram it into the cabinet, it is really small already
I guess it will stay like this (it is OK)

I have another crossover question for you experts if I may. Do these two passive dedicated crossovers appear to be doing anything other than applying the high+low pass and (presumably) attenuating the tweeter? I assume any response-shaping like baffle-step, etc. would be too specific to a particular enclosure.

 

[ppataki]

applying the high+low pass and (presumably) attenuating the tweeter?

That's all at best (judging by the measurements)