SB Acoustics Bromo

[RHO]

Could always just build some treatments. I'll never buy them premade because the mark up is just too high on premades. I have friends that bought a couple 2-3" premades for the same cost it took me to make like six 4" panels. They're super easy to make too, especially with your skills.

What materials did you use for damping?
Did you also build diffusors?

 

[D!sco]

That tweeter is straight out of the Jetsons. Great color choices all around. Nice work!

 

[Paweł L]

They look nice, the cutting boards from IKEA certainly add character. As for the boomy bass, they might need shelf filter since they sit close to walls and on top of the desk. Maybe stuffing the port with foam would help. Did you try them away from walls the way most spkrs this size are placed?

 

[RHO]

They look nice, the cutting boards from IKEA certainly add character. As for the boomy bass, they might need shelf filter since they sit close to walls and on top of the desk. Maybe stuffing the port with foam would help. Did you try them away from walls the way most spkrs this size are placed?

Thank you.

Not tried them away from the walls yet. I tried stuffing the ports but that didn't help much.
REW measurements are in the planning.

 

[JayGilb]

They turned out beautiful and I like your approach to using the cutting boards as front panels.

 

[dalbert02]

I think they look beautiful. I want to build a pair myself for the same application. Perhaps a slightly smaller cabinet would get rid of the boominess and crossover to a sub for <120Hz?

 

[RHO]

I think they look beautiful. I want to build a pair myself for the same application. Perhaps a slightly smaller cabinet would get rid of the boominess and crossover to a sub for <120Hz?

Thanks!
Yes, finally they will be supported by a sub. But I didn't have time to spend on measurements and optimizing the setup lately.
Maybe after the summer.

 

[Paweł L]

The 17NBAC-4, CAC-4 are slightly boomy. I tried it in bigger, smaller box, bass reflex, passive rad. This one is around 14L. I think passive rad was the best. They just have this kind of signature, possibly due to distortions - see Erin's test. Also, I measured amp distortions with the spkrs connected and there was rise in dist below 100Hz due to impedance and phase changes. Maybe the 8ohm version is more kind to amplifiers, but it's Qts is much larger.

 

[RHO]

The 17NBAC-4, CAC-4 are slightly boomy. I tried it in bigger, smaller box, bass reflex, passive rad. This one is around 14L. I think passive rad was the best. They just have this kind of signature, possibly due to distortions - see Erin's test. Also, I measured amp distortions with the spkrs connected and there was rise in dist below 100Hz due to impedance and phase changes. Maybe the 8ohm version is more kind to amplifiers, but it's Qts is much larger.

I asked Erin and he said he does not see any issue in using these drivers in a nearfield application. The problem is that these do not have sufficient Xmax capability to produce decent amount of low bass at higher SPL. But since I'm sitting quite close they do not need the SPL capabilities otherwise needed when listening mid or far field.
The boomyness could be the result of the placement.
I will cross them over to a capable subwoofer later.

 

[Paweł L]

Sure they can be used in the near field, but bass performance and it's character are most likely distortions related. Actually all 17, 15 SB drivers seem to have similar bass performance, some likely related to suspension nonlinearity, some due to motor design. And it not only me who says that, but a lot of people find their bass to be 'subwoofer' like. What intrigues me is the rise in amplifier distortions below 100Hz. It might just this particular Denon receiver, but it's amp is capable of 120W at 8ohms and it's big 17A Sanken output transistors should drive the 17NBAC easily. I will repeat the measurement with another amplifier. Then when one looks closely at impedance curve of SB drivers they all have these wiggles below 150Hz: could they be related to suspension linearity issues - their damper is a bit undersized for the cone comparing to most of the 6-7" drivers on the market.