Subwoofer integration without external DSP

[tomita]

I'm planning adding a subwoofer to my system, but I don't want to use external DSP. Are there any guides I should follow in order to phase (/time) align the subwoofer to the mains solely by positioning and through the sub's own dsp settings (crossover, phase, etc.)?
Can it be done?

Thank you

 

[fpitas]

If the sub has DSP, what is the problem using that? Of course without knowing a lot more about its capabilities, maybe it's not good enough. Tough to say.

 

[sigbergaudio]

You will get a better result if you can highpass your speakers. So ideally you should look into an external DSP solution. Phase/timing isn't necessarily a problem, true time aligning is impossible as the phase will vary with frequency.

You will have less issues if both subwoofer and speakers are sealed (not bass reflex).

 

[tomita]

If the sub has DSP, what is the problem using that? Of course without knowing a lot more about its capabilities, maybe it's not good enough. Tough to say.

No problem at all. I said I'm not going to use an external DSP. The subwoofer I'm considering is a SVS one, if that helps.

 

[tomita]

You will get a better result if you can highpass your speakers. So ideally you should look into an external DSP solution. Phase/timing isn't necessarily a problem, true time aligning is impossible as the phase will vary with frequency.

You will have less issues if both subwoofer and speakers are sealed (not bass reflex).

I know, but I don't want to go down that route. I want to make as much of a good integration as the interanl DSP of the subwoofer permits. The subwoofer will be sealed; the speakers, however, are ported – Kef R3.

 

[fpitas]

No problem at all. I said I'm not going to use an external DSP. The subwoofer I'm considering is a SVS one, if that helps.

That's a start. Got a link to a datasheet?

 

[tomita]

That's a start. Got a link to a datasheet?

Here you go!

 

[fpitas]

Here you go!

Thanks. Their idea of a datasheet is a glossy sales cut-sheet, unfortunately. Unless I missed some serious technical description of the DSP.

SVS App Specs:​

• Powerful Bluetooth-controlled subwoofer DSP app works with iOS, Android, and Amazon operating systems
• Provides easy and convenient way to adjust crossover frequencies, parametric EQ, polarity, room gain and all other bass-management functions
• Three convenient custom presets allow for perfect tuning in any room or system, from your favorite seat

• Bidirectional-feedback shows adjustments in real time on both app and subwoofer rear panel interface

 

[JayGilb]

What are you using to drive your Kef speakers ?

 

[dasdoing]

If you don't want to high-pass the mains, you should match the low-pass of the subwoofer to the natural roll-off of the mains as well as possible. then you apply delay on a trial-and-error basis until you have the most SPL at the crossover. your sub will be probably a cycle too late though (360-degree shift), but most people won't hear that.

 

[fpitas]

If you don't want to high-pass the mains, you should match the low-pass of the subwoofer to the natural roll-off of the mains as well as possible. then you apply delay on a trial-and-error basis until you have the most SPL at the crossover. your sub will be probably a cycle too late though (360-degree shift), but most people won't hear that.

So far we're not sure the SVS app does delay.

 

[dasdoing]

So far we're not sure the SVS app does delay.

the "phase" setting is probably delay, since there is polarity also

 

[fpitas]

the "phase" setting is probably delay, since there is polarity also

View attachment 314854

Maybe?

 

[dasdoing]

switch polarity first. leave polarity whatever gets most SPL before messing with the phase setting. if the polarity inversion gets you more SPL you will need less delay to match

 

[dasdoing]

Maybe?

I mean, what else would it be? an all-pass? I think these are generally delay when they are not simple polarity inversions

 

[fpitas]

I mean, what else would it be? an all-pass? I think these are generally delay when they are not simple polarity inversions

I'll take your word for it. This consumer grade stuff drives me crazy.

 

[tomita]

Thanks. Their idea of a datasheet is a glossy sales cut-sheet, unfortunately. Unless I missed some serious technical description of the DSP.

SVS App Specs:​

• Powerful Bluetooth-controlled subwoofer DSP app works with iOS, Android, and Amazon operating systems
• Provides easy and convenient way to adjust crossover frequencies, parametric EQ, polarity, room gain and all other bass-management functions
• Three convenient custom presets allow for perfect tuning in any room or system, from your favorite seat
• Bidirectional-feedback shows adjustments in real time on both app and subwoofer rear panel interface

Are you looking for something specific? Maybe I can help. I tried to do my homework and I know a thing or two about their app's capabilities.

 

[tomita]

What are you using to drive your Kef speakers ?

Holo May DAC -> Holo Serene preamp -> Benchmark AHB2 poweramp.

 

[tomita]

So far we're not sure the SVS app does delay.

Just variable phase. Will that do it?

 

[dasdoing]

here is SVS confirming it's delay: https://www.svsound.com/blogs/glossary/phase

since it's from 0-180 degrees it probably depends on the lowpass setting.