or Connect
AVS › AVS Forum › Audio › Subwoofers, Bass, and Transducers › Mark Seaton's Terraform XL Discussion/Owner's Thread
New Posts  All Forums:Forum Nav:

Mark Seaton's Terraform XL Discussion/Owner's Thread

post #1 of 191
Thread Starter 
Hey All,

I thought that since we are getting closer to the first official Terraform XLs entering into the world, that I would start a thread on it...there's another individual that has also ordered a pair (he can jump in here if he wants to, but I don't want to publicly name him yet! )

Some info:

http://www.seaton-sound-forum.com/

Terraform XL

* High Output, Ultra Low Frequency specialty subwoofer design
* Two(2) 15" drivers (internally mounted)
* Two(2) 18" passive radiators (HF chamber)
* large enclosure with slot vent tuned to ~12Hz
* DSP Controlled (manufacturer only) ICEpower amplifier (2000w/1200w sustained)
* Tentative dimensions: 52" x 22.5" x 28"
* Weight: Likely to approach 200 lbs

For Mark's Terraform/Terraform XL, he has coupled the high frequency chamber to the 18" passive radiators, and the rear drives the large slot vent which is tuned to the low teens. The Terraform XL doubles the number of drivers and PRs and more than doubles the power, but keeps the box size to less than double a Terraform.

As I get some more info and others chime in, I'll keep this original post updated with info.

Hopefully, they will be finished within the next month.
post #2 of 191
sounds liked another winner!
post #3 of 191
So this is ported and has PR's as well. Interesting, hope Mark will chime in to explain this in more details.
post #4 of 191
Quote:


52" x 22.5" x 28"

That is one long beast, I have ported subs built into my HT room wall that long!!
post #5 of 191
Quote:
Originally Posted by thehun View Post

So this is ported and has PR's as well. Interesting, hope Mark will chime in to explain this in more details.

basically from what I understand this is a band pass design (therefore there are two different port frequencies) one for the chamber on the front side of the driver and another on the back side of the driver. The use of a passive radiator is similar to a port. So instead of having a box with 2 sets of ports, it has a slot port and a PR. Why? only mark will know for sure... Its certainly a far more complex design than the sealed submersive. I look forward to hearing a pair of em soon as I know the nameless gentlemen who is anxiously waiting on a pair of these.....

Sean
post #6 of 191
Thread Starter 
Quote:
Originally Posted by sean_w_smith View Post

basically from what I understand this is a band pass design (therefore there are two different port frequencies) one for the chamber on the front side of the driver and another on the back side of the driver. The use of a passive radiator is similar to a port. So instead of having a box with 2 sets of ports, it has a slot port and a PR. Why? only mark will know for sure... Its certainly a far more complex design than the sealed submersive. I look forward to hearing a pair of em soon as I know the nameless gentlemen who is anxiously waiting on a pair of these.....

Sean

I hope he'll chime in on here as well!

That is also my understanding - as far as the design goes.

I didn't want to post too many details as Mark hasn't really publicly announced this design in any kind of specifics, yet.

When I initially talked with him months ago I was very intrigued by the combination of the passive radiator AND ported sub combo. Tuned right and likely utilizing the same idea as the submersive (room gain) this will be an amazing sub.
post #7 of 191
Thanks for starting this thread Joseph. Can't wait for Mark to go into more details about this unique design. I'm wondering about sound quaility and it's output capabilities. I remember Mark mentioning that it works best below 60-50hz, or something like that. Don't quote me though.
post #8 of 191
That will be bigger than my Conquest.

Bill
post #9 of 191
What will be the performance advantages be over the Submersive? Is the 28" dimension deep or wide? What kind of output potential?
post #10 of 191
Quote:
Originally Posted by bsoko2 View Post

That will be bigger than my Conquest.

Bill

I guess you'll need a second
post #11 of 191
I am also curious re: the output potential and will be able to compare them side-by-side with 4 Submersives, or run them all in tandem!
There will likely be another meet...
post #12 of 191
I talked to Mark about these before I bought my Submersives. He suggested they would be better for my situation, but I felt they were just too big. Mark stated that the Terraforms have significantly more output in the Infrasonic range than the Submersives. His extact words were "greater end rewards, especially below 20-25 Hz".

Also, I don't know who's getting the XL's, but Itai, (cubesys here on AVS), has a working pair of Terraforms in his house and others have heard them:
http://seatonsound.websitetoolbox.com/post?id=2381183

Sounds like another very special product from Mark.

Craig
post #13 of 191
Mark, I was wondering if you can answer my question about the Terraform XL/Submersive combination. I was wondering if you use the 2 TXLs(without highpass filters) for everything 20hz and lower and 2 Submersives for everything above 20hz, what can you expect from the TXLs? Would this be better in a 4000 cubic ft room than 4 Submersives?
post #14 of 191
Quote:
Originally Posted by sean_w_smith View Post

basically from what I understand this is a band pass design (therefore there are two different port frequencies) one for the chamber on the front side of the driver and another on the back side of the driver. The use of a passive radiator is similar to a port. So instead of having a box with 2 sets of ports, it has a slot port and a PR. Why? only mark will know for sure... Its certainly a far more complex design than the sealed submersive. I look forward to hearing a pair of em soon as I know the nameless gentlemen who is anxiously waiting on a pair of these.....

Sean

Its simply two subs in one.....you could build/buy two 15" subs to do the same thing as one Terraform XL.
post #15 of 191
Quote:
Originally Posted by Dbuudo07 View Post

Mark, I was wondering if you can answer my question about the Terraform XL/Submersive combination. I was wondering if you use the 2 TXLs(without highpass filters) for everything 20hz and lower and 2 Submersives for everything above 20hz, what can you expect from the TXLs? Would this be better in a 4000 cubic ft room than 4 Submersives?

I still think you need to put 2 Thigpen rotrary subs in your monster custom HT They would handle the ultra low frequencies and then just add Submersives.

How is the project coming along? I was in Mississauga last week, I thought about contacting you but I was too busy
post #16 of 191
Project is not going too good. I'm having some personal problems and I'm going to have to put the ultra theater on hold. I'm going to do a small home theater in my basement instead for know until I can do the ultra. I WILL do it one day, just can't in the near future. Thanks for the help though Penn. The small room will be 23' x 17' x 10'.
Next time you're in town, let me know.
post #17 of 191
Quote:
Originally Posted by Dbuudo07 View Post

The small room will be 23' x 17' x 10'.

WOW! What was the BIG room?
post #18 of 191
Quote:
Originally Posted by audioguy View Post

WOW! What was the BIG room?

It will be around 60' x 45' x 24'.
post #19 of 191
Quote:
Originally Posted by Dbuudo07 View Post

It will be around 60' x 45' x 24'.

Holy Crap.
I don't know what else to say.
post #20 of 191
Quote:
Originally Posted by Dbuudo07 View Post

Mark, I was wondering if you can answer my question about the Terraform XL/Submersive combination. I was wondering if you use the 2 TXLs(without highpass filters) for everything 20hz and lower and 2 Submersives for everything above 20hz, what can you expect from the TXLs? Would this be better in a 4000 cubic ft room than 4 Submersives?

An ideal, although more involved setup, would be 2 Terraform XLs with 2-4 SubMersives with the low end limited to 30-40Hz. The SubMersives would be preferably placed on different walls/locations than the Terraforms XL's which would likely go in a corner or 2 corners, or possibly front and center. The exact locations and spectral duty of each would be dependent on the acoustics of the room, but this would take maximum advantage of the huge capability of the SubMersive in the upper octave vs. its size, as well as the very clean and significant output of the Terraform XL pair.

Obviously such a solution takes up a bit of space, and you better have a seriously well constructed room.
post #21 of 191
Quote:
Originally Posted by penngray View Post

Its simply two subs in one.....you could build/buy two 15" subs to do the same thing as one Terraform XL.

Not entirely. The Terraform XL design is not as large as 2 of Itai's prototype Terraform subs. There are some things you can do with very large enclosures which don't scale particularly well in practical use, even though you can always theoretically cut a design in half and create a driver to match half the performance. The ports in particular are where the things get a bit tougher in practice, as 2 ports do not generally perform equal to one port 2x the size (all else equal - which it almost never is).
post #22 of 191
Thank you Mark. I always appreciate your help. I think four concrete walls and polished concrete floors above on the main floor should be enough to keep the room intact. It will, won't it?
post #23 of 191
Wondered if my room will have any issues with 2 of the XL's.....
post #24 of 191
Thread Starter 
Quote:
Originally Posted by Mark Seaton View Post

An ideal, although more involved setup, would be 2 Terraform XLs with 2-4 SubMersives with the low end limited to 30-40Hz. The SubMersives would be preferably placed on different walls/locations than the Terraforms XL's which would likely go in a corner or 2 corners, or possibly front and center. The exact locations and spectral duty of each would be dependent on the acoustics of the room, but this would take maximum advantage of the huge capability of the SubMersive in the upper octave vs. its size, as well as the very clean and significant output of the Terraform XL pair.

Obviously such a solution takes up a bit of space, and you better have a seriously well constructed room.

It sounds like you would basically be making the Submersives act as MBMs...which is insane to think about!
post #25 of 191
Quote:
Originally Posted by Johnsteph10 View Post

It sounds like you would basically be making the Submersives act as MBMs...which is insane to think about!

You gotta love his vision!
post #26 of 191
Mark, what do you do if your speakers are very capable down to 60-50hz? Will the Terraform XLs be as good up to those frequencies if your weren't using the SubMersives? It would be strange/wasteful to use another set of subwoofers for just 30hz-60hz no?
post #27 of 191
Quote:
Originally Posted by Mark Seaton View Post

Not entirely. The Terraform XL design is not as large as 2 of Itai's prototype Terraform subs. There are some things you can do with very large enclosures which don't scale particularly well in practical use, even though you can always theoretically cut a design in half and create a driver to match half the performance. The ports in particular are where the things get a bit tougher in practice, as 2 ports do not generally perform equal to one port 2x the size (all else equal - which it almost never is).

Thanks, I knew my overly simplistic and inaccurate post would get your attention
post #28 of 191
Quote:
Originally Posted by Mark Seaton View Post

An ideal, although more involved setup, would be 2 Terraform XLs with 2-4 SubMersives with the low end limited to 30-40Hz. The SubMersives would be preferably placed on different walls/locations than the Terraforms XL's which would likely go in a corner or 2 corners, or possibly front and center. The exact locations and spectral duty of each would be dependent on the acoustics of the room, but this would take maximum advantage of the huge capability of the SubMersive in the upper octave vs. its size, as well as the very clean and significant output of the Terraform XL pair.

Obviously such a solution takes up a bit of space, and you better have a seriously well constructed room.

Nothing below 30hz and nothing above 40hz or 30 to 40hz on up or down?

You better have a seriously well constructed bank account as well.
post #29 of 191
Quote:
Originally Posted by MIkeDuke View Post

Holy Crap.
I don't know what else to say.

Yeah, his project was going to be amazing.

I think his current room will be even more incredible though. Now he can focus on 2 rows and not 15 rows

David, Mark is still your main (I hope). I know another member called "theBland" or someting similar and I think his name is Jeff (??) has an incredible HT room, you should search for what he has and I believe Mark's expertise was involved. Outside of that MKTheater has one of the best HT rooms around (He did the DIY thing)....his dynamics are unmatched from all accounts (Measurements) and opinions. Btw, we are building high SPL, dynamic waveguide speakers right now. I could build an extra set and bring them to Canada in December
post #30 of 191
Quote:
Originally Posted by James W. Johnson View Post

Nothing below 30hz and nothing above 40hz or 30 to 40hz on up or down?

You better have a seriously well constructed bank account as well.

If you followed the original thread, I doubt $$$ is a concern for Dbuudo07 but who knows because when markets turn nasty and Bear Stearn, Lehman's etc go under people do lose millions.
New Posts  All Forums:Forum Nav:
  Return Home
AVS › AVS Forum › Audio › Subwoofers, Bass, and Transducers › Mark Seaton's Terraform XL Discussion/Owner's Thread