New Sigberg Audio development thread: The Sentinel - A music oriented reference subwoofer developed for the Manta system.

[SigbergAudio]

Fair enough ... how about distortion in the deepest bass?

Will the Sentinel be better? BTW, I assume one can buy the Sentinel on its own, without the Manta (?).

Distortion will be very low within it's linear working area. The goal is also to have advanced limiting so that distortion will be kept low (relatively speaking) no matter what you do. So low distortion will be prioritized higher than absolute maximum SPL.

I do not have the final drivers, the final cabinet or the final amplifier, so I cannot give you any hard numbers.

Yes, it will be possible to purchase the Sentinel individually.

 

[David_M]

Distortion will be very low within it's linear working area. The goal is also to have advanced limiting so that distortion will be kept low (relatively speaking) no matter what you do. So low distortion will be prioritized higher than absolute maximum SPL.

I do not have the final drivers, the final cabinet or the final amplifier, so I cannot give you any hard numbers.

Yes, it will be possible to purchase the Sentinel individually.

One trick I've seen modern sub designers use is to have dual coils on the driver, butted right next to each other. The second coil adds to the B field at the end of the 1st coil, where it's not linear anymore, essentially extending the constant magnetic field from the 1st coil, up to the Xmax, or as close to it as practical. That way, the coil inductance is constant regardless of travel, reducing distortion of the driver.

 

[SigbergAudio]

Wohoo, sample amplifiers have arrived! They were way larger than I anticipated. Looks very promising!

 

[SigbergAudio]

Up and running with the new amplifier now, after some startup trouble (the programming cable was wired incorrectly).

 

[SigbergAudio]

Another small detail (preliminary / subject to change): Since the weight will be around 60kg, there will be indentations for better grip when handling under the subwoofer.

 

[Tom C]

Another small detail (preliminary / subject to change): Since the weight will be around 60kg, there will be indentations for better grip when handling under the subwoofer.

View attachment 563096

Very thoughtful. So often overlooked.

 

[David_M]

Are you open to rounding the corners of the sub (e.g., like SVS subs) instead of the traditional sharp, square box shape? Rounded corners make it easier to hold or lift the subwoofer than a sharp, square shape.

 

[Keith_W]

Wohoo, sample amplifiers have arrived! They were way larger than I anticipated. Looks very promising!

"Larger than you anticipated" does not sound good. I would have thought that they should manufacture the amplifier exactly as you designed it

 

[SigbergAudio]

"Larger than you anticipated" does not sound good. I would have thought that they should manufacture the amplifier exactly as you designed it

It is an OEM amplifier.

Beyond that I did of course know the dimensions in advance, but it was still larger than I pictured.

 

[SigbergAudio]

Are you open to rounding the corners of the sub (e.g., like SVS subs) instead of the traditional sharp, square box shape? Rounded corners make it easier to hold or lift the subwoofer than a sharp, square shape.

The current Inkognito and 10D has some roundover, but no, that is not the plan on this or future products. Hopefully you won't be carrying it around that much.

 

[SigbergAudio]

Current nearfield response, pretty clean up to 300hz, so it can be crossed over high as well if one would want to do that.

 

[David_M]

Does near-field response approximate anechoic response?

Where would the typical 3-dB point be in room?

 

[SigbergAudio]

Does near-field response approximate anechoic response?

Where would the typical 3-dB point be in room?

Yes, it's relatively close to a freefield / groundplane / anechoic measurement.

F3 in-room will depend on the room. I'd expect it to be below 20hz in a medium room. In my relatively small listening room it's below 10hz currently.