DIY sub for Klipschorn based HT (and music) - Tuba HT - build done (except for finish)!

[ClaudeJ1]

LOL

[CECAA850]

An IB is an Infinite Baffle subwoofer. Basically, you're sitting in the subwoofer. It requires 2 to 4 long throw subwoofwers and normally a pro type amp to drive them. The "baffle" is normally one of the walls in the listening area. You only use (hear) the front wave of the drivers and the rear wave is wasted to an adjacent room, normally an attic, garage, closet, etc. There are no boxes in the room and it's the cleanest bass you could imagine. The down side is that you have to cut a hole in a wall, floor or ceiling to make it work! You can find more info HERE. The drivers can be mounted in a manifold with one opening to the room, or an array (like I have) where they all face the room. Again, there's trade offs to both designs but the manifold style is more popular. I've had people over to my house to listen to my system and if the room is dark, you wouldn't know there was a sub there at all. It sounds like my mains have a limitless bottom end. They're incredible for music and pretty much laugh at all the movie soundtracks that seem to challenge other subs. They're not practical in some rooms due to adjacent rooms, but if you have the correct layout, it's a no brainer. I'm fortunate to have an attic that I can waste the back wave of my drivers to.

[CECAA850]

What he meant was an SB or sealed box. An IB is infinte baffle which means wall mounting to the outdoors. It's still direct radiator bass which is full of distortion and dynamic compression. All woofers start to thermally compress dynamics at 10% of their rated RMS power..........only horns can prevent this.

I actually meant IB.

That's why there's multiple drivers, to lessen the power per driver needed for the required SPL.

A driver in a horn loaded config won't thermally compress if it's fed more than 10% of it's rated power? What in a horn changes this?

[ClaudeJ1]

An IB is an Infinite Baffle subwoofer. Basically, you're sitting in the subwoofer. It requires 2 to 4 long throw subwoofwers and normally a pro type amp to drive them. The "baffle" is normally one of the walls in the listening area. You only use (hear) the front wave of the drivers and the rear wave is wasted to an adjacent room, normally an attic, garage, closet, etc. There are no boxes in the room and it's the cleanest bass you could imagine. The down side is that you have to cut a hole in a wall, floor or ceiling to make it work! You can find more info HERE. The drivers can be mounted in a manifold with one opening to the room, or an array (like I have) where they all face the room. Again, there's trade offs to both designs but the manifold style is more popular. I've had people over to my house to listen to my system and if the room is dark, you wouldn't know there was a sub there at all. It sounds like my mains have a limitless bottom end. They're incredible for music and pretty much laugh at all the movie soundtracks that seem to challenge other subs. They're not practical in some rooms due to adjacent rooms, but if you have the correct layout, it's a no brainer. I'm fortunate to have an attic that I can waste the back wave of my drivers to.

Well, damn! That sounds pretty cool. So you are just using lots of motors, surface area, and power. Gotcha. I'm sure it sound amazing. I'm just trying to do the same with a single $159 driver, $90 worth of Oak plywood in a coffee table configuration, and $15 worth of fasterners and glue, all driven by an old 2j00W power amp and the mono LFE of my Onkyo Receiver. So if we throw in the non-destructive nature of the beast (no holes in wall) along with the PRICE/perfomrnace ratio.........it will make sense for some people besides me.

[CECAA850]

Every sub that I have ever owned has been a compromise in one fashion or another. I do like trying different ones however. The IB came out of a need for more floor space in my living room. With a Klipsch 7.1 setup and 2 subs, the walls started closing in. Completely ridding myself of subwoofer boxes really opened up our living area. As far as price vs performance goes, it may not be high on the charts. Based solely on performance, it's WAY up the charts. It's also has the highest WAF that you could ask for, if that's what's important to you. I'd love to build the sub you posted in your diagram, just to try it, but I just don't have the room. It would be my 5'th sub build (6'th counting the IB).

[Vicoaster]

Regarding IB, I suppose I just needed to remember back a few years when I built such speakers... I just jumped to the conclusion that this was some new methodology for sound reproduction! []

Also years ago I toyed with this idea, speakers in the wall the rear wave isolated from the from but the wife at that time nixed that idea promptly!

Although low extension is very desirable, the cost must be considered as well, interestingly I have a good room for this idea and may investigate it at some point in the future, but for now as Claude mentions, taking everything into account the horn solution has some definite advantages (especially since I have 2 suitable speakers already).

So it will either be a pair of Tuba HT's or tapped Horns as soon as I decide (or are convinced) which would be better! Still worried about the placement of the two choices. If I have to have the Tuba facing into a corner it will have to be behind the main listening area.

[CECAA850]

Sounds like a plan. Typically you are the only person who can say what the best sub is for your particular application. It's fun though to see how many different ways there are to skin that cat.

[Vicoaster]

CECAA850, I aggree with what you say above, but as I already have the 2 drivers, I might as well make something with them!

Do you have some photo's and specs for your setup?

Every sub that I have ever owned has been a compromise in one fashion or another. I do like trying different ones however. The IB came out of a need for more floor space in my living room. With a Klipsch 7.1 setup and 2 subs, the walls started closing in. Completely ridding myself of subwoofer boxes really opened up our living area. As far as price vs performance goes, it may not be high on the charts. Based solely on performance, it's WAY up the charts. It's also has the highest WAF that you could ask for, if that's what's important to you. I'd love to build the sub you posted in your diagram, just to try it, but I just don't have the room. It would be my 5'th sub build (6'th counting the IB).

[CECAA850]

Absolutely, use what you have.

If you scroll down this page till you hit "CarlP" you'll see a couple of really bad pics of the front and back of my drivers. Those were scanned pics of photos from a disposable camera. It's all I had at the time. You can also go the photobucket and search for "cecaa850". I believe there's some pics there but my filter here at work won't let me over there to provide you with a link. Those aren't the greatest either. I've since gotten a digital camera, but haven't gotten a good pic of my HT. My living room has no natural light and my flash isn't up to the task.

Carl

http://home.comcast.net/~infinitelybaffled/page3IB-Gallery3.html

[psg]

Hi all! This is great! Kind off a catch-all thread on alternate sub options. I liked the idea of a horn-loaded sub, the THT, to complement my horn-loaded speakers. The SPUD was also the tapped horn option that I investigated and placement wasn't optimal for me. I had seen that LAB12 design but didn't think it went that low. I should have looked into IB since I have a utility room adjacent to my HT room. I figured it might get too loud in the kitchen above that utility room (I assumed that it got louder in the adjacent room, but maybe I'm wrong about that). So, for me, for now, it's a THT. We'll see what the future brings. The IB is still a possibility in the future, but I do have the room for the THT in my 21.2x18.5 room.

[Vicoaster]

Hi all! This is great! Kind off a catch-all thread on alternate sub options. I liked the idea of a horn-loaded sub, the THT, to complement my horn-loaded speakers. The SPUD was also the tapped horn option that I investigated and placement wasn't optimal for me. I had seen that LAB12 design but didn't think it went that low. I should have looked into IB since I have a utility room adjacent to my HT room. I figured it might get too loud in the kitchen above that utility room (I assumed that it got louder in the adjacent room, but maybe I'm wrong about that). So, for me, for now, it's a THT. We'll see what the future brings. The IB is still a possibility in the future, but I do have the room for the THT in my 21.2x18.5 room.

I'll say, I am glad that you don't mind the intrusion!

As I said earlier since I have the 2 x 12" Eminence LAB speakers I might as well build some TUBA's or tapped horns with them, that way if I decide to dive into the world of IB I can sell a working set of subs!

The other thing is I will need some time to save for 4 18" subs (seems to be the popular configuration) along with some significant amplifier power! I haven't come across the cost for such beasts but it surely can't be inexpensive!

[CECAA850]

No, they're not cheap. Roughly 800 for 4 18" drivers and 350 for an amp. I'd do it angain in a heartbeat though. You get a sub that displaces about 30 litres per stroke. The commercial equivalent (if there even IS one) would be astronomical. The only thing that I can think of that would go lower is a Thigpen rotary sub (fan) that will run you about the cost of a new car.

[tragusa3]

Peter, assuming you get that THT to play nice in your room, you will not feel any urge to try another sub option. Outside of just being curious!

Hey, my Danley's can mimic an IB (irritable bowels). When my Dad was last visiting we watched "Flight" of the Phoenix. That plane crash at 120db left him physically ill. He told me I had to stop that it gave him Irritated Bowles. LOL! True story. He got sick.

[Vicoaster]

I'm about to build a tapped horn for my lone LAB woofer 30x60x14.5 inches.. I already have cut pieces for 2 original Danley LAB horns to replace my MWMs in my stacks, but no funds for the 3 extra drivers I need (bought Heresy's and Fortes for other rooms instead) so that will be on hold until 2011.

the tapped horn is from the DIY forum on the Tapped Horn project and uses only one LAB 12 woofer per box.. Field proven to go lower (like 16.5 Hz) than the Tuba in a 15 cu ft. box, but lower efficiency.Mine will be an oak coffee table. Only need 2 sheets of oak plywood.

As much as I would like to get started on either the tapped horn or the TUBA HT, the wife has her(our) kitchen in the project list before the home theater stuff so I am hold a bit as well...

From what you say above the single 12 tapped horn has been built by others, do you have some direct reports of the build and end results? Is the single driver version you are planning to build the one you posted the plan for?

Also you mention that you were going to make a pair of Danley LAB horns, even have to wood cut, are these plans available? I was reading where the driver used in the Danley had significantly different electromagnetic parameters then the Eminence LAB 12... So is the design you have different?

Thanks!

[Vicoaster]

No, they're not cheap. Roughly 800 for 4 18" drivers and 350 for an amp. I'd do it angain in a heartbeat though. You get a sub that displaces about 30 litres per stroke. The commercial equivalent (if there even IS one) would be astronomical. The only thing that I can think of that would go lower is a Thigpen rotary sub (fan) that will run you about the cost of a new car.

Could you tell me what drivers you used and if you were doing it again would they still be the ones of choice?

[CECAA850]

Could you tell me what drivers you used and if you were doing it again would they still be the ones of choice?

I used Ascendantaudio Avalanche drivers, which aren't made anymore. If I were building one today, I'd use the 18" version of THESE . Ficaraudio does all the warranty repairs for Ascendantaudio and builds drivers for them. It's a great company with excellent customer service. I've bought 5 drivers from them so far for other projects and have been very pleased.

[CECAA850]

Here's one of their 10" drivers I have in my car.

[Vicoaster]

Could you tell me what drivers you used and if you were doing it again would they still be the ones of choice?

I used Ascendantaudio Avalanche drivers, which aren't made anymore. If I were building one today, I'd use the 18" version of THESE . Ficaraudio does all the warranty repairs for Ascendantaudio and builds drivers for them. It's a great company with excellent customer service. I've bought 5 drivers from them so far for other projects and have been very pleased.

Hmmmm, maybe I have been looking at too many comercially built subs but from what I see at the Ficaraudio site these are too badly priced, sure 4 of them adds up but wow what an effect they would have on the HT experience!

So would you wire them as 2 pairs driven by separate sub channels? How much power?

Dang, you have me looking at that back wall of the HT thinking speaker cutouts... yeah, yeah they would fit just fine... room 21x16x8... this could be interesting!

How does Audyssey handle such things?

[CECAA850]

I have mine powered by a Behringer EP-2500 (EP-4000 now). I run 2 speakers per channel wired for a 2 Ohm load per channel. Audyssey would handle it just like any other subwoofer. The effect on HT is incredible, you feel things even when you don't hear them. There's a scene in Pearl Harbor when one of the characters is walking down the hall in a destroyer. You can feel the big diesel engines running but barely hear them, just like you would in the ship. I've even had people look for transducers in my couch. Music is equally impressive with crystal clear string bass and phenominally clear drums.

[CECAA850]

As much as I hate to do it, I'm going back OT[]. I listened to Dark Side if the Moon last night with my little Tuba 18 handling the bottom end. I'm sure you are all familiar with the heartbeat at the beginning and end of the disc (album). The sound of the heart beat was EXTREMELY clear compared to previous subs I've used. (No, I haven't listened to it on the IB). There was a distinct beginning (attack) to the beat and an equally distinct end to the beat with no "overhang" or bluring of one beat to the next. Very nice.