Two Voxel subs into one bigger sub?

[Apenut80]

Good day everyone,

Question:
I’ve built two Voxel subs. If size is not a constraint, can I somehow build one sub out of the two Voxels’ hardware (2 Tangband W5 1138-SMF’s and 2 LP-168S’s) to make a sub with bigger output?


The back story:
a while ago I’ve built myself a 5.1.2 set with mt Overnight Sensations and a mmtmm OS as a center. For the sub I built a Voxel with the recommended Lepy LP-168S amp.

This worked fantastic for 75% of the time, but especially in movies with the volume up at bass heavy scenes the sub couldn’t keep up. So I decided to just build a second one, again with its own LP-168S amp.

Now together they can keep up 97% of the time so great success! But I think we wouldn’t be here if we didn’t look for improvement all the time lol.

Also a huge thanks to mr Carmody for enriching my life with great sound and great projects!

[djg]

1+1=2. If I were unhappy with my two Voxels for my HT, i think I would build one or two bigger more powerful subs, and consign the Voxels to PC and bedroom sound. That's what I would do.

That way you can just enjoy the HT subject matter without thinking about your subwoofer performance.

[dynamo]

Placement of a sub can be challenging, and placement is more important than the sub size itself. I’ve seen some pretty mighty subs sound like nothing when in a bad spot.

A great way to combat this even better is two separate well placed subs. If sticking with the voxels, instead of combining them, I would keep them separate and find the two best places in the room for them.

[djg]

I was gonna say that but I didn't.

[billfitzmaurice]

Absolutely. Two smaller subs placed ideally will almost always beat one large sub, by smoothing out room modes. Use an RTA app with C weighting, placing the phone in the listening position while playing the sub test tone on the AVR. Start with one sub, moving it in the room to find the best result. Then add the other sub and move it until the combined output gives the best result. That said, the TB W5 is never going to give good results on home theater low frequency effects. If that's what you're after you need at least a pair of eights, if not tens.

[dynamo]

“I was gonna say that but I didn't.”

I figured, I agree to more substantial subs for HT like you suggested. That’s what I made sure I put if he sticks with the Voxel, as your suggestion has a lot of merit.

[Apenut80]

djg, dynamo, billfitzmaurice

Thanks for the responses guys. I guess I’m going to have to build a more substantial sub, as unfortunately there just aren’t many placement options in my living room.

Do you happen to have any great diy sub suggestions?
Thanks again and have a great day!

(edit: the room I’m working with is about 15 x 20 ft, concrete with hard wood floor, if that makes a difference.)

[billfitzmaurice]

Subs are like 800 pound gorillas. Where do they go? Wherever they want to. Arbitrary placement of subs based on where they look best, where they're most convenient or where your wife will allow them is a short road to bad results. So is using just one sub. As for the room, hard reflective surfaces are the enemy of good sound. The cure is rugs on the floor, treatments on the walls and lots of upholstered furniture.

[dynamo]

Don’t forget to consider the option of wireless transmitters for the sub(s). Then you just need an outlet. I put a cheap little 8” klipsch htib sub in for a friend that was wireless. Best spot was at the end of a short hallway about 20 feet from the listening position. Almost seemed to horn load the sub into the room a little lol. So point being, don’t think you need to have the sub somewhere front and center.

If you do build or buy a new sub for HT, my best advice is do it right the first time. Most of the time (not all), cheap subs sound like cheap subs. Good subs make you want to watch movies. Low frequency response (close to 20hz extension or less as you can get (this usually also forces a quality -not necessarily expensive- driver), good power, a solidly built well braced enclosure, and a big port.

The big diameter port is key if going vented as movies play low and a small port will chuff and sound like crap. By large I mean 4” diameter minimum with generous flares on both ends (I’d say a 3” precision port for a 10” driver would probably be minimally ok). This also requires it to be longer of course, increasing enclosure size.

The enclosure of a game changer subwoofer is often large. The rule (Hoffmans iron law) for speaker enclosures: loud, low, small; pick two and forget the third.

In my experience the sub makes or breaks a home theater. Modern receivers with built in room correction, crossover, eq, etc can do a lot with small speakers. A proper sub makes the difference imo.

[a4eaudio]

Do you happen to have any great diy sub suggestions?

What are the budget and size constraints?

[dynamo]

If you can spare a large sub but want a great value on a driver, I’d look hard at this: https://www.parts-express.com/GRS-12...820?quantity=1

Put it in the recommended vented enclosure, and run a 250w amp.

[Wolf]

MX10-22 with 300D amp, boost on, 0.75ft^3 sealed and stuffed.
As from PE;
BOX = $92
MX10-22 = $110
SPA300D = $150

Works great!
Wolf

[dynamo]

Good call Ben; small, inexpensive, easy build, no port chuff, cool looking driver!