Sigberg Audio SBS.1 Active speakers development thread

[sigbergaudio]

We're now approaching the end of the DSP development, and the default configuration sounds very good now. The default preset is neutral (basically flat anechoically from 100-20,000hz).

With the amps we are using there's a built-in EQ which means the competent end-user may use this to compensate/adjust the sound either to taste or to calibrate for the room. In addition to this, there are three presets that can be selected with the click of a button on the back of the speakers. We're now looking into how we configure those.

Our current thinking is to offer two alternative sound signatures in additional to the neutral default. These can bese used either if you simply think they sound better, or to compensate for a very reflective (sparsely furnitured) or very dampened room. The differences between the presets will be relatively small, typically the differences is withing 1-2dB in any frequency range. While subtle, it's enough to notice.
Below is an illustration of how these may look (not finalized).

Preset 1: Reference / Neutral
Preset 2: A small lift in the bottom, reduced energy in the 1-5khz area which can be perceived as harsh if there's too much due to rooms with a lot of reflective surfaces, and possibly a small gradual downwards slope from 10khz.
Preset 3: A small lift from 5khz and above for those who prefer a bit of extra "air" or sparkle, and/or has a room where this makes sense (very large and/or extra dampening)

 

[sigbergaudio]

For those who are uncertain about the capacity of such a system, here's a quick and dirty video of the SBS.1 + Two 10D Subwoofers playing 110-111dB @ listening position. For those who notice that there's a lot of movement in the speaker drivers, there is. The final product will have a 4th order low end roll-off, the current setup is only 2nd order. This will reduce the excursion by 30-50% depending on the frequency. Let me point out that even in this configuration, output is still clean at this volume.

https://fb.watch/5p770ELC0C/

 

[sigbergaudio]

Second generation pre-production models have arrived, now with detachable magnet grilles. Really starting to look good!

In other news, all the things that needs to be wrapped up to finalize both the SBS.1 speakers and the new 10D subwoofers before summer is starting to get out of hand, so we've decided to postpone delivery of both the speakers and the subwoofers until August. This gives us time to ensure proper quality control instead of rushing things out just for the sake of it.

 

[sigbergaudio]

..and in black

 

[sigbergaudio]

As the cabinets are now finalized and sales are starting soon, we're still tweaking. But now the goal is no longer the flattest response possible. We're now releasing the speakers a bit, accepting slightly less precision in exchange for fewer EQ points to avoid "restricted" sound. After this measurement (this is 15 degrees), the peak at 3khz has been tamed, and we've also reduced 5-6khz a little bit as there's a little bit much on-axis there (see below). The peak at 350hz is a reflection.

The result is now +/-3dB on-axis from 90-19,5khz. Does it sound good? Yes, yes it does!


0-15-30:

 

[sigbergaudio]

The limiter is now configured to allow 110dB+ @1m anechoically from two speakers which is what we set out to achieve, which should translate to Loud Enough for most purposes.

102,6dB @ 90hz/1m outdoors with one speakers results in 12,6% THD (primarily 2.harmonic), which is pretty respectable from 2x5.5" drivers. At this frequency the subwoofer(s) will be adding to the SPL as well.

In the other end things are looking good too:

109,5dB @ 5khz/1m outdoors with one speaker results in 1,48% THD.

Both these numbers increases with 6dB with two speakers, so to 108,6dB and 114,5dB. Which means if you insist, you can in theory achieve 115dB@1m or even louder, but then the frequency response will be increasingly affected as the amplifier limits the lower frequencies. This also means you can really crank it without risking damage to the speakers.

These numbers are significantly louder than most people will ever play in their living room. At any normal (or even very loud) listening level, the THD levels are of course way lower. As shared earlier in the thread, THD is below 1% THD at all frequencies @96dB/1m.

 

[sigbergaudio]

A small bonus feature towards the end: Many people run their speakers with grilles to protect from kids, animals, or because their partner thinks it looks better. At the same time we know deep down inside that it would sound ever so slightly better without the grille.

Since part of our concept is excellent sound despite having products that are modest in size and can be partially hidden away, how about if you could run the speakers with the grille on without sacrificing sound quality?

Our plan all along was to have one reference preset, one slightly brighter and one slightly warmer. After doing some measurements with and without the grille, we decided to tune the "brighter" setting so that it compensates relatively precisely for the difference with or without the grille.

This means you can now run your speakers with the grilles left on, and still sleep at night, because the DSP will compensate for the small loss from the grille. I have no idea whether this is a unique feature, but I've never heard of a speaker that has it.

Anyway, below the green graphs are with the grilles on, and red is without. The bottom pair is without any compensation, so here you can see the (pretty small) impact the grilles have on the frequency response. And then the upper pair is where it gets interesting. The red graph is preset 1 without grille, and the green is preset 2 with grille. Pretty cool?

 

[AHo]

This means you can now run your speakers with the grilles left on, and still sleep at night, because the DSP will compensate for the small loss from the grille.

very considerate! And ofc it brings additional bragging rights too

 

[Celloman]

Congrats for the fine development of your monitor. Do you plan to send a pair for review to Amir ? with one or two or your subs ?

 

[sigbergaudio]

Congrats for the fine development of your monitor. Do you plan to send a pair for review to Amir ? with one or two or your subs ?

Thank you! Not sure yet, it's a somewhat complicated process with regards to VAT both when sending it and on returning it, and also Amir in general doesn't accept products from new manufacturers, understandably so since apparently when he has done so in the past there has been a lot of bad products which have basically been a waste of time to test.

We've got the SBS.1 speakers + two 10D subwoofers on review in a Norwegian magazine at the moment, due to be published after summer. So we'll share that when it's out. It will however be your typical subjective magazine review, not lots of measurements.

 

[sigbergaudio]

A photo and sneak peek from the ongoing review at the Norwegian Magazine Stereopluss. There are two 10D subwoofers here as well, hiding behind each speaker.

 

[Deleted member 15250]

lol I like how you hang the grill on the side of your speaker stands. So these use a coaxial tweeter/midrange on top and a woofer on the bottom?

 

[extenso]

We've got the SBS.1 speakers + two 10D subwoofers on review in a Norwegian magazine at the moment, due to be published after summer. So we'll share that when it's out. It will however be your typical subjective magazine review, not lots of measurements.

Stereo+?

 

[sigbergaudio]

lol I like how you hang the grill on the side of your speaker stands. So these use a coaxial tweeter/midrange on top and a woofer on the bottom?

They're 2.5-way, so the coax has a tweeter as well as a midbass that plays all the way down, and there is also a separate midbass that plays only the lower frequencies. This gives maximum capacity in the bass/lower midrange.

The loudspeaker is designed to play with subwoofers, so both midbass drivers rolls off at around 90hz. This means the speaker has exceptional capacity and dynamic capabilities for its size.

 

[abdo123]

@sigbergaudio

When you say the limiter allows 110dB+ @1m how much +/- dB are we looking at anechoicly from 100Hz to 20KHz? in other words when does it start compressing anechoicly?

 

[sigbergaudio]

@sigbergaudio

When you say the limiter allows 110dB+ @1m how much +/- dB are we looking at anechoicly from 100Hz to 20KHz? in other words when does it start compressing anechoicly?

Well it doesn't compress until 110dB+. As listed above, we measured 102,6dB@1m at 90hz with one speaker. That's 108,6dB with two speakers, and at 90hz it's 3dB down. Which means I guess the answer to your question is that it's at 111,6dB@1m +/-3dB from 90-20,000hz with two speakers. Subtract 6dB to get one speaker. So it starts to compress in the low end around 111dB anechocally (105dB@1m with one speaker).

It could obviously play significantly louder than this in the higher frequencies, but this is how far it will go without compressing in the low end. In a real life situation the number is probably even higher, since the low end will be supported by a subwoofer in the crossover area.

 

[abdo123]

Well it doesn't compress until 110dB+. As listed above, we measured 102,6dB@1m at 90hz with one speaker. That's 108,6dB with two speakers, and at 90hz it's 3dB down. Which means I guess the answer to your question is that it's at 111,6dB@1m +/-3dB from 90-20,000hz with two speakers. Subtract 6dB to get one speaker. So it starts to compress in the low end around 111dB anechocally (105dB@1m with one speaker).

It could obviously play significantly louder than this in the higher frequencies, but this is how far it will go without compressing in the low end. In a real life situation the number is probably even higher, since the low end will be supported by a subwoofer in the crossover area.

you seem to be adding +6 dB instead of +3dB for the addition of a second speaker. Any reason why that I might be missing? As far as i can recall doubling the voltage is +6 dB and doubling the sound power is +3 dB.

I was interested in seeing if the Speaker can work for Home cinema, perhaps at one meter but probably a tiny bit short at 3 or 4 meters .

 

[sigbergaudio]

you seem to be adding +6 dB instead of +3dB for the addition of a second speaker. Any reason why that I might be missing? As far as i can recall doubling the voltage is +6 dB and doubling the sound power is +3 dB.

I was interested in seeing if the Speaker can work for Home cinema, perhaps at one meter but probably a tiny bit short at 3 or 4 meters .

So these are active speakers, we are adding twice the drivers and also twice the power = 6dB.

I'm positive these will work very well in a LCR setup. One of my own setups are a 5.1 setup, listening position maybe 3.5 meters away from the speakers, the gunshots were so loud I thought someone was trying to kill me while watching The Accountant.

Remember that these numbers are anechocially/outdoors. Playing Rage Against The Machine at 110dB at listening position indoors sounds completely uncompressed and effortless. And it also makes you want ear protection pretty quickly.

We made a quick and dirty video of SBS.1 + 2x 10D playing in excess of 110dB at listening position for those who didn't believe it: https://fb.watch/v/1FpL_V6Lj/ - since this video was made we've also added steeper highpass filters, so the drivers don't move nearly as much at this playback level.

 

[abdo123]

So these are active speakers, we are adding twice the drivers and also twice the power = 6dB.

Sorry to bother you but can you break that down for me please?

 

[sigbergaudio]

Sorry to bother you but can you break that down for me please?

Say you have one active subwoofer, and then add another. How many dB will you gain? 6db. Why is that? You gain 3dB by doubling the power (our system now have two identical amps instead of one), and also you now suddenly have two drivers, each moving the same amount of air as our single subwoofer. This means double the amount of air moved = 6dB gain. The result is similar to 4x power one a single subwoofer, assuming it could have coped with that.

So twice the power + twice the number of drivers.


This effect naturally works exactly the same with two active speakers.