Subwoofers - crazy upgrade!


I’ve read it for decades , every where. Never tried a sub

Till now.  What a shame!  This is amazing.  Just 1 hour

in my system and not fully broken in or calibrated. opens

Up the mains, deepens stage, adds bass detail.  More

Soulful/open- dynamic- easy.  Svs 3000 micro R.  I do NOT

get the physical body compression, but musically wonderful!

I can overblow it a little to feel it though .  I have it on the stock feet.

i think elevation would allow more volume and gain to get 

a physical impact while keeping it clean.  What an enjoyable 

subwoofer!!
 

cdtd
gdaddy1

534 posts

 

@lewinskih01 

The corner placement is also a good location. I ended up moving mine out about 12". An added benifit is running the bottom sub at 40hz and the upper sub HIGHER at around 60hz to gain midbass. They MUST be stacked as close as possible to couple properly. Feet removed. Thin rubber shelf liner between them.

 

  • Double the amplifier power = +3 dB
    • If each subwoofer has its own amplifier producing the same output as before, you've doubled the acoustic power.
    • Doubling power gives a 3 dB increase.
  • Double the cone area = +3 dB
    • The cones are moving together in phase.
    • The effective radiating area doubles, so they move twice as much air.
    • That produces another 3 dB.

@gdaddy1 

I'm afraid that's not correct.

I assume your system has a way to adjust response to a target you want to work with? If you don't and add 6dB in part of the frequency response...it won't sound true to the source. Maybe you'll like it, but that's a different point.

Doubling the amp power does indeed add 3dB assuming both amps are still playing at the same power as they did before, which shouldn't be the case if you are preserving the target response.

Same thing with doubling the cone surface: if the amps were driven at the same power as before that would add 3dB, but they shouldn't be per the above.

Maybe your system doesn't allow to adjust to a target curve and you are indeed adding 3dB and you like it better. Maybe you were needing a boost in the lower octave.

Or maybe you did adjust to a target curve and then the subs are now working at half the prior excursion and distortion is much lower and is audible. Not sure what subs you have.

In my case, going from 2 Rythmiks F12 to 4 didn't make the bass louder (as I did adjust the power to a target) and I couldn't tell if they were distorting less (they weren't to start with), but the improvement came from a more homogeneous bass response across the room.

By using the 1/4, 3/4 type of placement, you also eliminate the issues at 1/8th, 3/8th, 5/8th, 7/8th positions --> harman virtual sub principle

For the height dimension, raising a sub to the 1/4 height, 2 feet up is easy to do. For a 3/4th heightwise lift, room to start to look like a lab if you have it sitting on a 6 foot stand (in this example). Might be cleaner to do in-wall, in-ceiling, etc.

Eitherway, you see why a room with longer dimensions is a easy fix for the strong modes with subs (long dimensions = strong modes get pushed down into the sub range). In a small room, where these modes bump above 100 to 120 hz, i.e., above the sub range, there is no other choice, but thick diaphragmatic absorption, etc  to treat it --> which further eats away into a already small room. Further, the modes are packed closer together in a small room and its not easy to try and position yourself out of anything either.

You can eliminate a lot of issues with even 2 subs, if you have freedom of placement. 

@akgwhiz wrote

Fidelity of each sub notwithstanding. There have been many threads based on DBA and this topic.  @deep_333 that looks awesome.  But since room nodes occur at even fractions of room dimensions (1, 1/2, 1/4) it might be optimal to have 2 of the 4 at odd ratios like 1/3 of the wall lengths.  But if one has a dedicated space and sitting location (most here do that), maybe this isnt a worthy consideration. That was my takeaway from my reading and understanding of the virtues of multi subs.  Personally haven't gotten past 2 subs, lol.

 

Try a vertical 4 driver sub with drivers at height like a tekton 4-10. I doubt that guy ever makes a profit selling subs like that for $860. His profit margin probably only covers a wendy's burger and a scooters coffee.

@buellrider97 wrote


Gentlemen, if I may ask a somewhat lame question please. Stacking subs Vs subs that have multiple front facing drivers ( 2 or 4 ) in the same enclosure with a single amp, are they comparable? I’d like to run multiple subs, but I can’t afford to pony up for 4. Also any comments on the Audiokinesis  Swarm is appreciated. I’m currently cash strapped and hoping to do something with a $3K budget. Thank you, Mike B. 

@deep_333 , Thank you for the advise. I have Tekton DI’s on Townshend Podiums. My question was veiled as I didn’t want to mention the Tekton subs , but that’s exactly what I was curious about. I can’t afford 4 REL’s , so it would probably boil down to a pair of SVS, Tektons or a Swarm. I’m currently running a modest SS kit amp. As soon as I get some balanced cables and relocate my TV, I’ll run the DI’s with 180 watt tube monos, but I still want subs. What’s your thoughts on the 4-10’s Vs the 2-10’s ? Regards , Mike B. 

Since your double impact has some legit ~30hz extension,  you could see if you room permits a [1/4,1/4], [1/4, 3/4] location for them, at which point they can also serve as part of the distributed bass array (this depends on your room size, of course).

It would imply that you put the 2 subs behind you at the [3/4, 1/4] [3/4, 3/4] or [3/4, 0] [ 3/4,1] locations and you would technically have a 4 sub array, where the double impacts also serve as quasi-subs.

Almost always, the ideal position for 2 subs would be behind the listening position if you have full-ish range speakers.

$640 for the 2-10 vs $860 for the 4-10...4-10 sounds like a better deal to me, especially since you can get physical drivers at the heightwise null locs with the 4-10.

@buellrider97 wrote

@deep_333 , Thank you for the advise. I have Tekton DI’s on Townshend Podiums. My question was veiled as I didn’t want to mention the Tekton subs , but that’s exactly what I was curious about. I can’t afford 4 REL’s , so it would probably boil down to a pair of SVS, Tektons or a Swarm. I’m currently running a modest SS kit amp. As soon as I get some balanced cables and relocate my TV, I’ll run the DI’s with 180 watt tube monos, but I still want subs. What’s your thoughts on the 4-10’s Vs the 2-10’s ? Regards , Mike B.