Tuba Home Theater Sub

The THT is a 20hz 18ft^3 horn and is pretty much unbeatable for 30-80hz output. Its a very efficient design in both power consumption and output.

With every design though, there are trade offs and for the tuba it is the 20hz roll off and its size. The roll off isn't really a bad thing because the tuba excells so well in the 30-80hz range where 90% of the movies produce LFE content. Its also cheap to build coming in at under $500 for the wood, amp, and driver.

I couldn't live with two 24" wide tubas so I built one 24" with a 15" driver and am now in the process of adding a 17" wide with a 12" driver.

According to BFM, the output from the LP should be the same as the original THT. With regards to impedance & FR sweeps..."They're virtually identical to the THT as it's just a refolding of the box."

A single tuba should walk all over probably even 2 of the turbo kits. The cost would be a big point too. Around $400 for the tuba, and $1500 for two of the kits. The tuba will get a bit lower, play louder, and should have a cleaner response. The only downsides to the tuba is its big and you have to build it.

brandon, I thought the turbo upgrade gets down to the teens (18hz IIRC).

A couple of people have changed out their LLT setups for horns though tunegoon.

Brandon, having owned a pair of mfw's before, I would have definitely thought the tht would kick the crap out of a pair of mfw's but this user feels otherwise. If you read a couple posts after you'll see I was quite surprised to learn that he felt the two were roughly equal.

A THT will slaughter a pair of mfw-15s. It's not even a fair comparison.

My LP is 13 feet away from my subs. Here are some examples of how ridiculous the THT output is. Sorry about the audio, my poor camera mic can't keep up. This is in 10k cubic feet of space with the door open to another 15k cubes

rat shack meter pegged at LP
http://www.youtube.com/watch?v=3cl129XTVo8

125db at LP with <50w to each THT
http://www.youtube.com/watch?v=hjYE823AH4k

I was clipping the input on the top run, bit of a REW limitation there.

The turbo upgrade does nothing to change the tuning of the enclosure. I may be wrong so don't quote me, but I believe its tuned somewhere around 25 hz. Yes there will be some output below that, but with the chance of damaging the driver unless they have modded that stand alone amp with a steep hpf. So really it's going to be meaningless for deeper extension with that kit. Yes, with the kit you will get louder and probably less distortion, but deeper extension won't happen.

Box size still matters, and that's where you get the huge gain where the horn still has leverage on the driver. As you get low enough, it's still a sealed woofer of whatever type you choose to use. The MFW-15 is tuned to about 19Hz, providing a good deal of useful output to 16-17Hz. While the biggest gain from the Turbo is down low, even above 35Hz a pair of MFW-15 Turbo's will deliver 122-125dB @1m with the originals only a couple dB behind in this upper octave. A horn can certainly produce more with sufficient power, as the smaller and higher cut off Growler makes a good example (~130dB @1m with 1kW). For most music use you should expect more from a large bass horn. As you get down below 25Hz, you need a very large/long horn and/or a driver with a good deal of excursion to push those gains low enough to deliver more output than that of the sealed drivers being used. As usual, if you want low and loud on the cheap, plan for BIG boxes.

Good choice. You'll be happy.


dbl

I switched from a single MFW to a THT and it was night and day difference. I have a huge space and I would still like a second one but I think THT will beat the MFW's and 2 should kill it. Just my thoughts

http://billfitzmaurice.info/forum/vi...p?f=30&t=12483

You could use Arauco plywood . Cheaper, yet still high quality lumber. Depends on the finish you want, I suppose.

its DIY people, if we think there is a new thing out there that is slightly better will offer a minimal improvement but take a lot of time to build and tweak they will build it.

As I have posted elsewhere, a single THT can play a little louder than two MFW-15s, but remember that a few dB doesn't amount to much at your ear, if all you are worried about is max SPL.

How long do people hang onto their $1k+ subs? Seems like people are switching to something else all the time. There is always something better out there.

The THTs put out a boat load of clean bass from 20hz up at a cheap price and a large size. I love mine. The SQ is excellent.