4 identical smaller subs vs vs 1 svs16 and other sh*t subs

[Guest niterida]

Yeah I didn't look that close - just saw 30hz and thought pfffft..............

[davewantsmoore]

On 6/24/2021 at 6:36 PM, davewantsmoore said:

Ultimately, it doesn't matter how many subs.. or how big they are.

Only that you have a flat frequency response in the listening seats, with low distortion at your desired SPL.

 

We need to know how loud you want to play (eg. do you really want "reference level", ie. 115dB bass in your seat?... or is less realistic) ..... and then check that your subs can perform ok at that level (ie. low distortion, ie. high SNR)

 

Then after that, it's just a matter of the frequency response, and dialing it in to not have unwanted peaks and dips in it.... and secondly, to be skewed to your taste.

 

Eg. if you want "slam", then you probably want the 60 to 120 region to be boosted quite a lot .... even if that means not as much boost below 60hz (to keep distortion in check) .... but the first step is ensuring no peaks and dips, especially dips which can just make the bass sound like it's MIA (ie. no slam).

 

[davewantsmoore]

1 minute ago, niterida said:

Yeah I didn't look that close - just saw 30hz and thought pfffft..............

 

They may be quoting -3dB or -6dB .... it doesn't say ..... but if it can make 130dB at 30Hz .... then not matter what, there is oooodles of useful output below 30Hz for a home setting, if you EQ it flat.

[Guest niterida]

Light Bulb moment 

Been playing with WinISD to build some DIY subs and I just realised if it can hit your required db at the required HZ (say 106db at 15hz) it doesn't matter if it is at -20db at that point since you can just EQ out the rest of the frequency range by up to 20db and it will be flat down to the desired freq  !!!! Thank you

at least I hope thats how it works ?? Anyway thats off topic - I will have a play with WinISD and start a new thread if I need to ..........

[Ittaku]

5 minutes ago, niterida said:

Light Bulb moment 

Been playing with WinISD to build some DIY subs and I just realised if it can hit your required db at the required HZ (say 106db at 15hz) it doesn't matter if it is at -20db at that point since you can just EQ out the rest of the frequency range by up to 20db and it will be flat down to the desired freq  !!!! Thank you

at least I hope thats how it works ?? Anyway thats off topic - I will have a play with WinISD and start a new thread if I need to ..........

Not unless you have a massive driver, as there are physical limits to how much air a driver can move. At 15Hz you need an awful lot of surface area to get to the same dB as at 30Hz. You'll just end up hitting the excursion limits and not getting any louder. Think about it - it's like getting a tweeter to do bass; you can't equalise a tweeter to give you loud enough bass. See this graph for how limiting even a (closed) 16" subwoofer is at those lower frequencies:

 

[Guest niterida]

7 minutes ago, Ittaku said:

Not unless you have a massive driver, as there are physical limits to how much air a driver can move. At 15Hz you need an awful lot of surface area to get to the same dB as at 30Hz. You'll just end up hitting the excursion limits and not getting any louder. Think about it - it's like getting a tweeter to do bass; you can't equalise a tweeter to give you loud enough bass. See this graph for how limiting even a (closed) 16" subwoofer is at those lower frequencies:

I was talking about the other way around - I want 30hz to be the same db as 15hz. 

[davewantsmoore]

1 hour ago, niterida said:

at least I hope thats how it works ??

 

Yes....... but it can be problematic letting a processor "measure and correct" the response in room.   It is better to design the EQ along with the subwoofer (like, design the EQ to correct what you see in WinISD or other sim..... rather than what you measure in a room).

[davewantsmoore]

1 hour ago, Ittaku said:

Not unless you have a massive driver, as there are physical limits

 

  You can EQ any driver flat ... but the SPL you can achieve is limited by the driver excursion and power handling.

[Guest niterida]

11 minutes ago, davewantsmoore said:

 

Yes....... but it can be problematic letting a processor "measure and correct" the response in room.   It is better to design the EQ along with the subwoofer (like, design the EQ to correct what you see in WinISD or other sim..... rather than what you measure in a room).

Yep that's what I meant.

[OzJustin]

Probably a silly question, but is there an accepted dB level where the 'chest slam' impact really becomes apparent? Is it possible to have a system produce this quality without having all speakers running ridiculously loud reference level? I.e. can gain on the LFE channel alone boost things to the required level while other channels won't make you deaf. Like the OP, I'm keen for some serious slam, but don't really want to destroy my relationship with the neighbours who are approx 8-10m away.

[Guest niterida]

40 minutes ago, OzJustin said:

Probably a silly question, but is there an accepted dB level where the 'chest slam' impact really becomes apparent? Is it possible to have a system produce this quality without having all speakers running ridiculously loud reference level? I.e. can gain on the LFE channel alone boost things to the required level while other channels won't make you deaf. Like the OP, I'm keen for some serious slam, but don't really want to destroy my relationship with the neighbours who are approx 8-10m away.

Build a  HoverBoss platform for the couch :

https://www.avsforum.com/threads/the-tactile-response-thread-for-bass.3081780/

[OzJustin]

42 minutes ago, niterida said:

Build a  HoverBoss platform for the couch :

https://www.avsforum.com/threads/the-tactile-response-thread-for-bass.3081780/

That will focus on the sub 30Hz rumble/shakes won't it? My reading to this point is that the 'chest slam' region is more 50-80Hz.

[Guest niterida]

34 minutes ago, OzJustin said:

That will focus on the sub 30Hz rumble/shakes won't it? My reading to this point is that the 'chest slam' region is more 50-80Hz.

Yes but when the couch physically hits you like the punch just thrown on the screen you won't care about not feeling the chest slam

Trust me it is the best thing I ever did in my room.

And it doesn't make much actual SPL

 

And I think I have derailed this thread enough - sorry

Edited July 26, 2021 by niterida

[Eli]

13 hours ago, niterida said:

Yes but when the couch physically hits you like the punch just thrown on the screen you won't care about not feeling the chest slam

Trust me it is the best thing I ever did in my room.

That would assume that the sound effect also has a 20-30Hz component. If a soundtrack effect is recorder/mixed with a lot of slam at 60-80Hz, you're not guaranteed there'll be associated 20-30Hz content also. So it would end up sounding quite thin.

[jamiebosco]

3 hours ago, Eli said:

That would assume that the sound effect also has a 20-30Hz component. If a soundtrack effect is recorder/mixed with a lot of slam at 60-80Hz, you're not guaranteed there'll be associated 20-30Hz content also. So it would end up sounding quite thin.

Usually people with Boss setups are also using BEQ (Bass EQ) to EQ the audio tracks in movies to bring up the under 30Hz content 

[Adam5022]

I ended up buying x2 svs sb3000s to add to my system. A bit pricey but judging by all the reviews and the good name of svs I couldn't say no.

 

I was torn between making my own, but a friend of mine gave me a good reason not to, as it gives me something to aspire to later haha

 

The subs should arrive soon, ill get some REW measurements and post them up as soon as I can