Sigberg Audio SBS.1 Active speakers development thread

[sigbergaudio]

Weather here in Norway is finally approaching something somewhat closer to spring (or at least less like winter), so I've now been able to do outside measurements and some adjustments based on these, so I can finally present som useable full range measurements without noise from the room.

These may still be subject to change, but starting to look pretty decent. If we ignore the dip at 1khz (which is 3dB), this is essentially +/-2dB in the intended frequency range.

(The dip just below 300hz at the 30-45deg measurements is probably reflections from the ground, not actual frequency response)

Finally, some asked about using the SBS.1 as a center speakers, so did a quick 0-15-15-15 measurements. What I did here was put the speaker on the side, and then measured On-axis, 15deg to the left, 15deg to the right, and 15deg above (simulating a placement below a screen). Pretty consistent response, so I see no issue with using this on its side as a center speaker. Response below.

 

[sigbergaudio]

New outdoor measurements today. We've now studied 0-60deg off-axis more intently to find the best compromise for the most even response and dispersion. This is really starting to look good.

There's a few issues between 200-500hz in these curves that will be fixed, just didn't get there today. May also relax 1-3khz ever so slightly.

Either way, the on-axis response now has less lift above 10khz, while keeping 15deg almost intact. This means 0-15degrees response (typically the three seats in the sofa) now are almost identical. The 30-60deg response is also very good.

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[sarumbear]

I am very happy to see a design based on a system explained on a paper published 43 years ago, in 1978, by my good friend Siegfried Linkwitz RIP. Siegfried's design was analogue (this was even before CD). A custom active crossover and pre-set filters were feeding separate amplifiers one oer each drive unit. Everything was designed and build by him.

https://www.linkwitzlab.com/Removed pages/x-sb80-3wy.htm

Trivia: When I read this article back in 1978 I chased him via AES and met at the next convention. Through the years we became good friends. We had stayed at each others house, discussing speaker design. I'm of Turkish origin. His wife Eike likes carpets. I am responsible for those carpets you see in the loudspeaker pictures taken in his living toom.

 

[sigbergaudio]

I am very happy to see a design based on a system explained on a paper published 43 years ago, in 1978, by my good friend Siegfried Linkwitz RIP. Siegfried's design was analogue (this was even before CD). A custom active crossover and pre-set filters were feeding separate amplifiers one oer each drive unit. Everything was designed and build by him.

https://www.linkwitzlab.com/Removed pages/x-sb80-3wy.htm

Trivia: When I read this article back in 1978 I chased him via AES and met at the next convention. Through the years we became good friends. We had stayed at each others house, discussing speaker design. I'm of Turkish origin. His wife Eike likes carpets. I am responsible for those carpets you see in the loudspeaker pictures taken in his living toom.

Thank you, and thank you for sharing, very interesting article. There are indeed a similar focus and priorities , and a number of similar ideas here. While I have never read this specific article before, I'm confident Linkwitz and other like him have inspired my own sources.

 

[sarumbear]

Thank you, and thank you for sharing, very interesting article. There are indeed a similar focus and priorities , and a number of similar ideas here. While I have never read this specific article before, I'm confident Linkwitz and other like him have inspired my own sources.

You are very welcome and I wish you all the success. It looks like you will end up with one hell of a system.

Me and a friend who is no longer with us designed, manufactured and sold a closefield monitor speakers back in early 90s. Seeing your development and the pictures made me remember our journey. We had exhibited at two APRS shows and one AES convention and sold about 1500 pairs but our heart was not into manufacturing; we stopped and wound up the operation. Speakers were generally well received in the market. Maybe when you have the time you will check its website that we kept for posterity.

silver5l.com

Thank you for listening

 

[restorer-john]

silver5l.co.uk

This website link appears to be non-functional.

 

[NYfan2]

This website link appears to be non-functional.

I guess this is the correct url:
https://silver5l.com/

 

[sarumbear]

This website link appears to be non-functional.

Sorry, wrong TLD. It should be silver5l.com. I corrected the post.

 

[sarumbear]

I guess this is the correct url:
https://silver5l.com/

Yes. Thank you.

 

[sigbergaudio]

You are very welcome and I wish you all the success. It looks like you will end up with one hell of a system.

Me and a friend who is no longer with us designed, manufactured and sold a closefield monitor speakers back in early 90s. Seeing your development and the pictures made me remember our journey. We had exhibited at two APRS shows and one AES convention and sold about 1500 pairs but our heart was not into manufacturing; we stopped and wound up the operation. Speakers were generally well received in the market. Maybe when you have the time you will check its website that we kept for posterity.

silver5l.com

Thank you for listening

Interesting, I like your philosophy of designing to requirements and design goals as opposed to cost, we do the same. This was also a 2.5-way system if I understand the specs correctly?

 

[sarumbear]

Interesting, I like your philosophy of designing to requirements and design goals as opposed to cost, we do the same. This was also a 2.5-way system if I understand the specs correctly?

5L is a 2-way speaker. A woofer and a tweeter crossing over at 1500Hz via a 4th order crossover with perfect LR response.

Instead of simply assuming a drive unit to have a fixed impedance we used filter theory and designed a complex circuit that took into account both drive units' impedance curves. We then used LEAP to calculate the component values via multiple iterations. Back in early 90s PCs didn't come with a floating point processor, it was an optional extra available of a few PCs. Even with it, calculations took hours! With multiple iterations, the process lasted a month. Now, any laptop will do the calculations almost instantly and you can finish any crossover design in a day.

The extra woofer you see is an augmenter that works up to around 350Hz via yet another filter to flatten the sloping upper-low frequency response that exists on every narrow baffle speaker. (The reciprocal of 4pi to 2pi change-over slope.)

 

[sigbergaudio]

5L is a 2-way speaker. A woofer and a tweeter crossing over at 1500Hz via a 4th order crossover with perfect LR response.

Instead of simply assuming a drive unit to have a fixed impedance we used filter theory and designed a complex circuit that took into account both drive units' impedance curves. We then used LEAP to calculate the component values via multiple iterations. Back in early 90s PCs didn't come with a floating point processor, it was an optional extra available of a few PCs. Even with it, calculations took hours! With multiple iterations, the process lasted a month. Now, any laptop will do the calculations almost instantly and you can finish any crossover design in a day.

The extra woofer you see is an augmenter that works up to around 350Hz via yet another filter to flatten the sloping upper-low frequency response that exists on every narrow baffle speaker. (The reciprocal of 4pi to 2pi change-over slope.)

So that's what I'd call 2.5-way. Both woofers play all the way down, but only one also do the midrange duties. Right?

 

[sarumbear]

So that's what I'd call 2.5-way. Both woofers play all the way down, but only one also do the midrange duties. Right?

Not exactly. The 2nd woofer does not have just a traditional low-pass filter. It has a filter that has a step response with a roughly 3dB/oct slope, which is the reciprocal of 4pi to 2pi change-over slope of the 5L box. It is to compensate the enclosure behaviour first explained by Olson in 1950 which was re-analysed by Tore Skogberg in 2006. It also has a 12dB/oct low-pass filter acting further up in the frequency range to avoid confusion around the crossover range by having three drivers emitting at the same time.

 

[sigbergaudio]

INTRODUCTION PRICE PER PAIR FOR ORDERS PLACED BEFORE JUNE 1ST: 39992NOK (~4850USD / 3990EUR)
(EXPORT PRICE WITHOUT VAT, LOCAL VAT/TAXES MAY APPLY. WORLD WIDE SHIPPING INCLUDED)

SBS.1 is an active speaker built to play with a subwoofer. By designing for a high crossover against a subwoofer, the result is a full range system uniquely capable of loud and clean music reproduction. The sound doesn't just surpass other speakers of similar size, combined with a subwoofer you get a soundstage comparable to high end floor standers.

Driver excursion is kept low and distortion kept to a minimum no matter how loud you play, providing effortless dynamics.

SBS.1 is of course a perfect match with one or several Sigberg Audio subwoofers, but can also be matched with high quality subwoofers from other brands.

Since the system is modular with small main speakers and a separate subwoofer, it fits in anywhere. The loudspeakers is both physically and visually subtle. The subwoofer may be placed out of sight and/or wherever the bass response is best. Combine SBS.1 with one of our Inkognito subwoofers and you'll get an almost invicible system that will literally blow your socks off! The ultimate combination would be adding two of our brand new Sigberg Audio 10D dual 10" subwoofers.

Note: You will get an additional 10% discount on the entire purchase if you combine your purchase of SBS.1 with one or more subwoofers

Read more and pre-order directly on our website at www.sigbergaudio.no

 

[sigbergaudio]

We keep on nudging and tweaking, never 100% satisfied, but I guess we have to call it a day soon.

0-15 degrees in the last iteration this evening, almost there now:

0-15-30-45 from a bit earlier this evening. Some energy left at 2300hz off-axis, and a bit much at 3khz, fixed this but didn't have time to repeat the off-axis measurements tonight. There's a small dip at 250hz too, but it's about 1dB so we're talking nitpicking now:

15deg (listening axis) is dangerously close to +/-1dB from 100hz to 15khz now, there's maybe three places it's dipping slightly below. So I guess it's technically +1/-2dB. It may not end up quite this flat since it may not be optimal when looking at the total dispersion, but it's indicative of the precision we're down to on the adjustments now..

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[sigbergaudio]

Many have already subscribed to our subwoofer playlist "Sigberg Audio Subwoofer Demo Tracks" on Spotify and Tidal.

We've now also started to curate a list of the tracks used during the development of our SBS.1 speakers. Check out our new playlist "Sigberg Audio Loudspeaker Demo Tracks". Available on Spotify and soon Tidal.

 

[thatchinaboi]

The cons of well designed coaxial speakers and monitors can be mostly or entirely mitigated by integrating a subwoofer to take care of the IMD and with a coaxial design with it's own fixed waveguide. You have to know the limits of your speakers in terms of max SPL before IMD becomes audible.

In terms of imaging and off axis response, I am of the opinion that conventional speaker designs are inferior. I have no plans on ever upgrading my current coaxial studio monitors. They are simply amazing, provided they are set-up optimally.

 

[sigbergaudio]

The cons of well designed coaxial speakers and monitors can be mostly or entirely mitigated by integrating a subwoofer to take care of the IMD and with a coaxial design with it's own fixed waveguide. You have to know the limits of your speakers in terms of max SPL before IMD becomes audible.

In terms of imaging and off axis response, I am of the opinion that conventional speaker designs are inferior. I have no plans on ever upgrading my current coaxial studio monitors. They are simply amazing, provided they are set-up optimally.

Which studio monitors do you own?

 

[thatchinaboi]

BTW my nearfield studio monitor setup consists of the Fluid Audio FX50s which were well reviewed my Amir, and a Mackie cr8-xbt studio subwoofer. What I find a bit annoying are the comments and responses from people that never heard the monitors for themselves. Despite Amir giving his recommendation, saying it is one of the best sounding small bookshelf speaker on the market, people commenting were quick to shoot it down. The objective tests are actually very good especially for the price, and subjectively the FX50s sounds incredible (especially when paired with a sealed subwoofer). The negative comments are most definitely due to expectation bias, brand bias, and price bias rather than actual listening experience. For those who were put off by the comments, and overlooked how the review was actually very complimentary despite not having the best score (for far field listening), I urge you to listen to the Fluid Audio FX50s yourself. Order it and try it before the return date and there is a very good chance you will be keeping them and raving about them.

(I find it ridiculous how a nearfield coaxial monitor is judged for it's theoretical far field performance from measurements of a single mono speaker. No one in the comments seem to think it is a bit silly and disingenuous.)

 

[thatchinaboi]

Interesting to note both Kali Audio and Fluid Audio design teams were former employees of JBL. All 3 companies have coaxial speaker designs.