Development thread: High-end dual opposing 10" subwoofer: Sigberg Audio 10D

[sigbergaudio]

Some of you may have checked out our Inkognito series, aka "high-end design subwoofer" (https://www.audiosciencereview.com/...gn-subwoofer-that-actually-sounds-good.15677/).

We're now looking at building our first "traditional" cube formed subwoofer. We're going with Hypex and Scan-Speak here as well. Mostly the same design goals apply. First and foremost as high quality and precise sound as possible (always our first priority), and second something that will look good in the living room and not be refrigerator sized. We also wanted to increase the output a bit over our Inkognito series. Rough size indication is 40x40x40 cm, or 15x15x15". It won't be exactly this size, but to give an impression.

The dual opposing design does a good job of eliminating cabinet resonances, the couch next to the subwoofer vibrates more than the enclosure.

Initial testing indicates a pretty impressive in-room response (-3dB at 14hz), as well as very low distortion at moderate levels. As the screenshot below indicates, we're at 1.4% THD at 20hz@81dB. Without naming names, there are competitors out there with a higher maximum SPL capacity than this subwoofer, but that are still at several times this distortion at the same output level. Aka built to play loud, but less attention spent on precise and distortion free reproduction. One could of course always argue about the audibility of this, but we'd like to focus on accurate sound before SPL. That being said, this will be able to play pretty loud too.

Stay tuned for updates, we hope to launch this product before summer.

 

[pozz]

It looks really nice. Too bad you're all the way in Europe. International shipping and customs duties are way too expensive.

 

[muslhead]

It looks really nice. Too bad you're all the way in Europe. International shipping and customs duties are way too expensive.

What he said
Would be interested as soon as they are available otherwise

 

[sigbergaudio]

It looks really nice. Too bad you're all the way in Europe. International shipping and customs duties are way too expensive.

What he said
Would be interested as soon as they are available otherwise

Free international shipping door-to-door.

 

[muslhead]

Free international shipping door-to-door.

nice. I will await your release

 

[sigbergaudio]

Added some Audyssey room correction and playing our 10D prototype together with a wall mounted Inkognito 10, and it's now essentially flat from 14.5-100hz in a normal living room (around 40-50m^2). This is with no smoothing applied.

 

[sigbergaudio]

And less than 2% distortion at 80dB at 15hz. Less than 1% THD from 26hz and up.

 

[Draki]

Very nice test results.
Are the tests done with speakers run "open" i.e. no LP filter applied (or EQ for that matter)?

 

[sigbergaudio]

Very nice test results.
Are the tests done with speakers run "open" i.e. no LP filter applied (or EQ for that matter)?

I choose not to disclose exactly what we do with regards to DSP, but the general answer is no. There are few if any subwoofers that would do 14hz in-room without any kind of EQ applied, especially moderately sized subwoofers.

With regards to low pass filter, the first post was without a low pass filter, the two most recent posts was with a 120hz low pass filter active.

 

[Draki]

Thanks. Understand about DSP and didn't mean to ask for a disclosure about it.
It is more about the LP (the FR graph is limited to 200): do you find a low order LP (looks like 1st?) more suitable, as in a better blending with the mains, than steeper ones?
This is not poking into your way of doing things, more a question of an approach, or a "philosophy" if you like. Dr. Geddes for instance is proponent of a 1st order sub LPs, and in practice (IME, with multiple subs, 2+) this works well but with Fc below 100s or 90s. So no judging, only asking for an opinion.

 

[watchnerd]

It does look nice.

Will there be an app to configure it via Bluetooth or WiFi from my phone while sitting in the listening position?

 

[sigbergaudio]

Thanks. Understand about DSP and didn't mean to ask for a disclosure about it.
It is more about the LP (the FR graph is limited to 200): do you find a low order LP (looks like 1st?) more suitable, as in a better blending with the mains, than steeper ones?
This is not poking into your way of doing things, more a question of an approach, or a "philosophy" if you like. Dr. Geddes for instance is proponent of a 1st order sub LPs, and in practice (IME, with multiple subs, 2+) this works well but with Fc below 100s or 90s. So no judging, only asking for an opinion.

Aha. Personally I'm of the opposite opinion, our subwoofers have 4th order low pass filters. 4th order filters means no phase shift, and also ensures a steep roll-off which helps reduce localisation issues if the subwoofer has an asymmetric placement (like over to one side). If you however do have subwoofer(s) symmetrically placed, this also makes it easier to get away with a pretty high crossover point, taking advantage of clean SPL from the subwoofer up to 100-120hz (or even higher).

 

[Draki]

Thank you for your response.

 

[sigbergaudio]

It does look nice.

Will there be an app to configure it via Bluetooth or WiFi from my phone while sitting in the listening position?

Thank you.

I would highly recommend anyone (even for 2.1 setups) to have an amplifier with active crossover/DSP/room correction support, as that will give superior results with regards to bass response compared to without. And in that case you would typically use the amplifier instead of the internal subwoofer settings.

If you do wish to adjust the EQ of the subwoofer, that can be done via USB and a laptop. I personally do both. I do initial setup of the subwoofers via the internal EQ to do broad EQ adjustments to get a reasonably flat response, and then run room calibration from the amplifier.

So no, there is currently no app support. There's a couple of reasons for that. First and foremost we are a small manufacturer so doing our own development of something like that currently isn't feasible, and second I like the thought of a subwoofer or a speaker to be relatively future proof despite being active. So adding app support, direct streaming abilities for Spotify or whatever would require us to focus on a lot of other things than maximum sound quality.

 

[phoenixdogfan]

And less than 2% distortion at 80dB at 15hz. Less than 1% THD from 26hz and up.

View attachment 102196

Great. What does it look like at 100 db? 105db? Can it even play that loud b/c 78.8 is not all that loud particularly for a bass fundamental.

 

[sigbergaudio]

Great. What does it look like at 100 db? 105db? Can it even play that loud b/c 78.8 is not all that loud particularly for a bass fundamental.

Haven't started compression tests yet. Based on simulations and the results from our current production subwoofers I'm guessing CEA2010 results for this model will be something along the lines of this:

92dB (2m RMS) / 101dB (1m Peak) @ 20hz.
104dB (2m RMS) / 113dB (1m Peak) @ 31,5hz.
114dB (2m RMS) / 123dB (1m Peak) @ 50hz.

Time will show. It will play plenty loud for music, we're not building subwoofers primarily for home theater use - though this will be plenty loud for that too at least for a living room situation. If you want multiple subwoofers in a dedicated home cinema, this probably isn't the right product, unless you have a really expensive setup and are also using it for music.

EDIT: Also wanted to make a point about the distortion at these moderate levels. This forum tends to focus a lot on CEA2010 measurements, which shows how a subwoofer acts when it's at its breaking point, essentially showing how loud it can play. But I've seen 12" subwoofers that are at 10% distortion at 80dB@20hz (and several % at way higher frequencies), so what we miss with the CEA2010 is that many subwoofers are breaking up way before that, and performing poorly at what is (as you put it) levels that are not all that loud. Which is the levels most of us play, most of the time, especially for music, and where we want it to be precise and distortion free.

 

[HooStat]

This sounds like a great product. You are definitely hitting the soft spots in the market. I tried to find a subwoofer that has a finished face that faces the listener/room that is reasonably sized but with good output. There are few, if any, choices. Arendal is one and there are a couple of others (Aperion). But that is it. At your approximate proposed size, it should be a nice choice for a lot of people. Good luck with it.

 

[sigbergaudio]

This sounds like a great product. You are definitely hitting the soft spots in the market. I tried to find a subwoofer that has a finished face that faces the listener/room that is reasonably sized but with good output. There are few, if any, choices. Arendal is one and there are a couple of others (Aperion). But that is it. At your approximate proposed size, it should be a nice choice for a lot of people. Good luck with it.

Thank you, I appreciate the feedback. I am aware that focusing on music over movies, and quality and design over maximum SPL when building subwoofers is somewhat of a niche. But there are tons of music lovers out there with high quality 2.0 setups, that after pouring money into their setups still don't have proper bass. And that should be running a 2.1 (or 2.2) setup.

There are also lots of people who have a mixed setup both for music and movies, but turn off their subwoofers when they listen to music. Either because they're unable to integrate it properly or because the subwoofer simply isn't good enough to match their expensive main speakers and stereo setups.

Or people with expensive 2-way speakers in the living room, who are unable to get "permission" to get a subwoofer or a large floorstander.

These are the main audiences we are hoping to give an even more awesome experience from their systems.

 

[sigbergaudio]

Here's what a poor driver with massive 2nd harmonic distortion may look like. This is a different 12" subwoofer (not ours) at roughly the same levels as my previous measurements. A whooping 28% distortion at 25hz. You could go down to 75dB and it's still above 10%. This would not be visible in a simple CEA2010 test, as it only shows the result at the subwoofer's breaking point. As you can see the distortion here is just way higher all the way from 80hz and down.

 

[Matias]

Is a dual 12" version coming too?