Axiom Home Page Forums General Discussion Technical Questions Lower subwoofer extension with EQ

I know it is possible to get a flatter response with subwoofer EQ, but is it possible to get lower extension? I'm not talking a huge gain but maybe a few db a few hz lower?

The reason I ask is now that I am getting settled into the long haul for my room I know at some point I will be upgrading my AVR to handle atmos\dts:x. I also know that the current AVR brand I use (Arcam) seems to be adopting Dirac as its onboard EQ solution. I'm just trying to get a grip on what is possible in the subwoofer realm and plan for possible upgrades or tweaks in the future.

I currently employ 2 SVS SB-12 NSD subs if that helps. Front wall, 1/4 placement.

With a ported subwoofer, gaining lower extension is almost impossible, assuming the subwoofer is a good design.

A ported sub is typically "eq'ed" to a flat response (anechoic) to its tuning frequency.

To attempt to gain additional flat response below this will tax the driver, as below the tuning frequency, drivers tend to "flap".

A sealed design is relatively easy to eq - multiple drivers are typically needed, but it's a fairly straight forward process to do so.

Just buy bigger & badder sealed subs, ha!

A nice pair of EP800s come to mind; however, you probably won't need nor want to EQ them as they go really low cleanly as a result of their superior design...

TAM

Anyone ever add a sealed sub into a room with a ported one?
I have a large SVS cylinder sub and my DIY acoustical clone (box, not cylinder) up front like Serenity does, and I keep wondering if a nice big sealed sub in the back would add more "punch" to the low end, or if it will just muddy the LFE.

Great news. Thanks.

I can get low extension and pleasing tactile response, but I have to inflate the sub level to a point where they are unbalanced with the mains at low but audible frequencies. I know the performance is there, I just have to unlock it.

Sorry Nick, I never played with mixing porteds and sealed units. Sold my last ported before the sealeds arrived. Our rooms are dang near the same size so I can tell you you'll want something with grunt if you go sealed. Mine are great, but I'm getting greedy for every last drop of performance.

I'd look at ep500 or sb-2000 as options. I wish I had waited 6 months. The sb-2000s seem to be tuned lower than the sb12 NSD units. Such is life. For what I paid I can't complain. They rocked my last room, but the new room has much greater volume.

I thought you had buttkickers?

You used to be able to buy a subharmonic synthesizer from Radio Shack of all places. I don't remember what it had for controls, but the jist is that if there was a frequency at 24Hz, it would create a corresponding signal at 12Hz at 6dB lower...mixed back in with the original. It would do this for all frequencies below a certain point, creating a harmonic lower in frequency and level than the originals. This was before subs were even talked about in HT.... and before HT itself was ever really talked about.

I've often wondered why a product like that is not re-introduced for the current crop of very capable subs.

Edit: I should have researched it before answering: dbx still makes one!

No doubt they would be fun, but way overkill for my 2400 cu ft room.

If I could hit rewind 2 sb-2000s or 2 sealed v4 ep500s would be perfect for this volume I think. Cheating extension with eq will be the cheapest solution for me I think.

Mark that sounds like an ideal solution for this type of workaround. Being able to add gain below a predetermined cutoff is brilliant.

check my post edit above

Thx, checked it out. Awesome tool, but only creates harmonics 26-56hz. Poo. This thing would make kick drums pound!