SB Acoustics

[Addicted to music]

On 20/6/2023 at 9:52 AM, THOMO said:

The SBA kits are missing the potential of their own drivers because they are narrow baffle /low sensitivity and wasting the higher sensitivity potential of their best tweeters.Gravesen seems to have grasped that potential with his wider baffle designs  incorporating highish sensitivity Satori tweeters and pro audio mids and woofers.They are proving to be his most popular designs.

I want a low realestate profile so a narrow baffle will tick the box.   
I heard a Monitor Audio Range from Bronze to there silver range. The silver has a small footprint but different drivers  and it was far more detail,  went lower in the bass and played louder than the larger bronze series with a higher cost.

[THOMO]

You might want to look into the Satori 761.Which is an open source design and uses quite simple first order crossovers so is an economical build.I used the top two drivers in my Meniscus Audio Kairos and they are excellent.The dimpled textile ring radiator tweeters sound very sweet and refined.Some people seem to prefer them to the berrylium versions which cost a lot more.

[Atlas Harry Gouverneur]

There are some differences between the Satori and the standard SB acoustic drivers. The paper woofers from both SB and satori lines have surround break up between 1-2k, which needs to be considered. While, the Satori lines have neodymium magnets, the effects are not huge, around half a db increase in sensitivity and 0.05 change in electrical demoing/Qes on average. The reduced impacts from rearward reflections from the motor assembly is likely to be real, however, I haven't confirmed so can't say for sure. 

 

As mentioned, one thing is that all models with paper cones share is surround break up, the texteme and ceramic versions don't have this issue due to the rigid diaphragm coupling. So, spending more on the diaphragm material is a worthy consideration if you want to avoid the surround break up issue. 

[davewantsmoore]

On 26/6/2023 at 6:15 PM, Goodsounds said:

surround break up

It's a good observation.

I found it does equalise out surprisingly well...

 

On 26/6/2023 at 6:15 PM, Goodsounds said:

The reduced impacts from rearward reflections from the motor assembly is likely to be real

I was interested in this most of all, but didn't find it to be an issue.... although I do use them with quite low crossover points (<<2k)

[Atlas Harry Gouverneur]

1 hour ago, davewantsmoore said:

It's a good observation.

I found it does equalise out surprisingly well...

 

I was interested in this most of all, but didn't find it to be an issue.... although I do use them with quite low crossover points (<<2k)

 

I have also found that shallow slopes to work well in filling in the surround break up area.

 

When equalizing, did you see an equal rise in THD in that area?

 

I asked a designer at SB Acoustics awhile back about this issue and their response was that they prefer a high Q dip opposed to a low Q, often seen on Scan Speak drivers and other drivers with thicker rubber surrounds. 

 

I'm sure most people reading this have seen it, but we can see how far some brands are willing to go to mitigate surround break up, namely Purifi. 

[crtexcnndrm99]

I’m also curious about the new SB Acoustics drivers.

 

Wondering how the 9.5” Textreme would compare to the SB29NRX2 (10” paper) in an implementation similar to the Symphony 10 speakers (2-way horn on compact bass reflex).

 

Fs is low on the SB29xxx however other specs are missing from their website, unless I’m missing something. 

 

 

[davewantsmoore]

6 hours ago, Goodsounds said:

When equalizing, did you see an equal rise in THD in that area?

I pay very little attention to THD .... as long as it isn't suddenly jumping out as a symptom of something.   So, no I didn't notice.

 

6 hours ago, Goodsounds said:

I asked a designer at SB Acoustics awhile back about this issue and their response was that they prefer a high Q dip opposed to a low Q

Very much.... but I look at the error over all the angles of radiation, and apply any correction in the context of the overall sound power.... so the correction, doesn't end up being particularly high Q.

 

6 hours ago, Goodsounds said:

I'm sure most people reading this have seen it, but we can see how far some brands are willing to go to mitigate surround break up, namely Purifi. 

Yes.

Is interesting .... Purifi talk about it in terms of Sd modulation (frequency response) and also the "break up" in terms of FR and THD/IMD....  as said, I don't pay any attention to THD, etc. unless it's fairly significant.

[THOMO]

14 hours ago, crtexcnndrm99 said:

I’m also curious about the new SB Acoustics drivers.

 

Wondering how the 9.5” Textreme would compare to the SB29NRX2 (10” paper) in an implementation similar to the Symphony 10 speakers (2-way horn on compact bass reflex).

 

Fs is low on the SB29xxx however other specs are missing from their website, unless I’m missing something. 

 

 

I have tried the  standard SB29NRX as part of the Kairos three way build.I could not get it to sound any good.

Typical modern hi fi woofer I guess.They are built for excursion and power handling  and low Fs and have low sensitivity. They are built more like ,and sound like ,subwoofers.It sounded slow and boomy and rhythmically poor.Give me a  cheap higher Fs,short excursion,low moving mass,low power handling ,high sensitivity bass guitar type woofer any day over that type.

Edited July 19, 2023 by THOMO

[davewantsmoore]

On 20/7/2023 at 9:38 AM, THOMO said:

Typical modern hi fi woofer

Yeah, they should almost call it (the NRX 10) a subwoofer.

 

On 20/7/2023 at 9:38 AM, THOMO said:

higher Fs,short excursion,low moving mass,low power handling ,high sensitivity

It's a difficult comparison, because the drivers need so much correction before the have the same frequency response in the range where they can overlap (when they will sound similar), eg 50 to 400Hz

 

.... otherwise all you are hearing is the difference in frequency response, which sounds just like you describe "slow and boomy and rhythmically poor".  (when comparing, eg.  30 to 450 vs 60 to 900)

[THOMO]

I blame modern processed electronic bass for that sort of woofer.They are built to handle that sort of computer generated noise without failing but that means their ability to accurately reproduce natural music is compromised.

Unfortunately many modern speakers sound like that.

[davewantsmoore]

1 hour ago, THOMO said:

their ability to accurately reproduce natural music is compromised.

It just means they are designed to operate over a different frequency range to the type of woofer you said you would prefer.

 

If you equalised their responses, and compared them over (the overlapping) range where they were both comfortable, you will get a much much more similar sound.

.... it isn't the driver which "slow boomy muddy" .... it is that frequency range sounds like that.    You will see (hear) this if you correct them to the same response.

[crtexcnndrm99]

I wonder if any of this SBA range will replicate the specific use case / type of the SEAS A26RE4 10” paper woofer (I.e., a 2-way, efficient, can be used for a high enough xo point, a la Devore or audio note or A26). Probably too specific or limited use I’d guess. 

[davewantsmoore]

1 hour ago, crtexcnndrm99 said:

I wonder if any of this SBA range will replicate the specific use case / type of the SEAS A26RE4 10” paper woofer (I.e., a 2-way, efficient, can be used for a high enough xo point, a la Devore or audio note or A26). Probably too specific or limited use I’d guess. 

They are as efficient, and will go lower.... as for the high crossover point, it depends on specifics ... as they all (the NRX, Satori, others) have an uneven response above ~2khz.

That being said, it also depends on what comprises the HF peak.... as it is never all "breakup", and the components which aren't non-linear can be equalised out very successfully (eg. diffraction due to the shape of the cone).

 

OTOH, while the Seas driver is a bit better behaved at HF ... it is all pushed down quite a lot due to the very (relatively) high inductance of the Seas motor, causing a strong rolloff at those frequencies.   IMVHO not a good driver to emulate, and not a good speaker to emulate.

 

The short answer is yes.... but as I was saying to Jon, compared in the raw they will be a bit different (not a drop-in-replacement) and so you would not want to make judgement by comparing the sound like that (before they had been corrected to a common response).

[BioBrian]

If anyone is interested in building Troels' SBAcoustics 3-Way Classic, a great-value 3-way speaker, I am passing on the 4" SBA mid-drivers to suit:

 

 

http://www.troelsgravesen.dk/SBAcoustics-3WC.htm