Curious about passive subwoofers – who’s using them and how?

[LF78]

I imagine passive subs have huge advantages in noise and would be really effective for a nearfield setup. Most subs I find have too much self-noise when you sit near them. There was a thread here on ASR where someone took their SVS SB1000 and hooked it up to an Aiyama amp and all the self-noise coming out of the sub went away.

Why is it like that though? I mean, class D plate amps should be based on the same components (Hypex, Icepower, etc...) of the standalone amps that don't have any noise issue at all typically.

 

[Sokel]

Why is it like that though? I mean, class D plate amps should be based on the same components (Hypex, Icepower, etc...) of the standalone amps that don't have any noise issue at all typically.

Unless they use their own alu thick-ish enclosure, from all sides, wood is not nice in suppressing noise.
Even the proximity to a huge magnetic structure matters, some of them became magnetic on their own.

Noise is inevitable sometimes.

 

[10PSPMemSticksForMiku2007]

I imagine passive subs have huge advantages in noise and would be really effective for a nearfield setup. Most subs I find have too much self-noise when you sit near them. There was a thread here on ASR where someone took their SVS SB1000 and hooked it up to an Aiyama amp and all the self-noise coming out of the sub went away.

There are some active subs without that issue including my own m&k mk2 that I use an arm's length away at my pc. It might also depend on how loud you turn up the amp. If you're sitting much closer you would have that knob lower and hopefully attenuate that noise along with the signal. If the volume control is purely digital and the amp gain isn't adjustable, you could end up with a lot of noise.
Volume is a factor. If you're playing at 85db the amp and its noise will be a lot lower than if you want to knock down your house with 110db bass.
There are also some sub designs like ported bandpass that actually filter out high frequency noise but mains hum is still a concern with them and tend to be large.

 

[Shrek6]

Something like this might help??:

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I caved and bought an RSL Speedwoofer 10e. The sealed enclosure for the 15" has no bracing, which is probably an issue that can't be solved with this. I have a car amplifier so it makes more sense to just sell both.

There also really seems to be a glaring lack of decent budget-y amplifiers for passive subwoofers that aren't plate amps. The Fosi M03 (or the near identical Nobsound and Aiyima offerings) is the closest to filling this void but it's underpowered for most of the desirable subwoofer drivers. Something like this ICEpower 300AS1 or similar would be better, as a standalone amplifier unit.

 

[levimax]

There also really seems to be a glaring lack of decent budget-y amplifiers for passive subwoofers that aren't plate amps.

Crown XLS series amps are powerful, reliable, have DSP, and are reasonably priced for what you are getting. Used ones can be a bargain. They also come in a variety of different power levels.

 

[EJ3]

Crown XLS series amps are powerful, reliable, have DSP, and are reasonably priced for what you are getting. Used ones can be a bargain. They also come in a variety of different power levels.

View attachment 491893

Changing the CROWN XLS fans out to some quieter computer fans also helps.