Lilmike's Cinema F-20 - Page 34

Sorry good catch Crown XLS1000 not XTi.

I am a big fan of the MiniDsp for its power and simplicity.

You just had me wondering there for a minute if I was missing something

James

t6902wf,
Running the subs in the room could be the cuprit. When I built my eD sono's for the first time I ran two of them and it was very little output. Once I put them into the corners of the room they were a whole new animal! Also, that room they are in is huge so getting the same spl will be more difficult than your room. The only way to really compare is put one in your room. The 20hz on up is really impressive so if they are not the room is just too big. These can hit 115 dbs outside at 20hz and if you are in a very large room it maybe the same indoors which means you will lose output from distance.

Hi Lilmike;
How would the Mayhem 15" dual 2 ohm perform in this box wired series for 4ohms?


Dual 2 Ω
Re 1.4 Ω
Fs 36 Hz
Qms 5.97
Qes 0.24
Qts 0.23
Mms 261 g
Sd 810 cm^2
Vas 68.9 l
SPL 93.1 1W/1m
Bl 26.2 Tesla Meters
Xmax 30mm (one-way)
RMS 2500w

If it works..... would the diff in performance over the Dayton RSS390HF-4 be worth considering?

Thanks

Thanks Mike.....

We got them installed in the furnace / backroom. There was still some wiring and finish work to do so we did not fire them up. Quite an impressive sight installed.



I'll get better install photos when it is running with some plots.

We ran some tests last night. My friend who was coming from 12" and 15" 15 year old definitive subwoofers said in the beginning, I don't see how it could be better.

I played the cannon battle scene from Master and Commander and his son came running down the stairs and said he thought the floor was going to cave in upstairs, rookies.

The room is so large that I was shocked at how well it energized it. I am not going to be able to get a flat curve. There are 2 suckouts with the placement we had to use.

It is going to take a bit more tweaking but I can't image getting more bass for the $1,000 we have into it. It is also a hidden install. I'll get some photos of that also. Good Job Lilmike

Has anybody tried the Dayton DCS380-4 15" with this build? I was planning on ordering the RSS390HF-4 for either a THT build or a Cinema F-20 build, but i keep staring at the DCS380 for nearly a hundred bucks cheaper and now i'm stuck with what i want to do going forward. I already got a Bash 500w plate amp to power whatever build i end up going with. I've tried over and over again to model it in Hornresp, but as much as i've tried to learn how to do it, i simply don't know the ins and outs of the program well enough to get any conclusive results.

So i guess my question is... has anyone tried using this driver with this build yet? If not, can anyone tell me how it models with this build and/or what i'd be giving up by going with the cheaper driver?

*** Here's the specs on the DCS380-4

T6, that's fantastic! I love to hear the enthusiasm. It's fun!

I just bought two of these cabinets (from beastaudio) and they are HUGE! I can hardly wait for the drivers to come in from Partsexpress. I ordered the DVC385-88 driver.

In my theatre build thread I have been making little videos about the process. I whipped this one together in honor of this fantastic subwoofer and I thought I'd share it here. Thanks, lilmike, for the plans for this behemoth!

Seconded! I can't WAIT!

I was trying to find this information throughout the thread, but I was wondering if the F-20 is similar to the THT in that you can make it as narrow as needed with only sacrificing a little bit of extension. So could I make an 18" wide F-20?

What driver would be recommended for a narrow f-20? I appreciate any help, I'm trying to integrate two horn subs into a built in shelving/entertainment center.

A very interesting project! Great of Mike to help people out with it, including plans.

Someone asked earlier about bass traps and corners. My experience has been that bass traps make a huge difference. I can't imagine not using them now. My first experiment made it sound like the bass had moved outdoors. Horns in the corner and bass traps in the corner can be tricky. In my case I'm planning some horn subs under the floor, then a bass trap over it. The corner will still work like a corner in terms of bass loading, the sub will load into the tri-corner. Bass traps don't absorb all bass in the room, they damp the modal ringing, resulting in much tighter bass. Bass traps can be made to blend into a room and not dominate, but size does matter. Bulkhead traps are also an option. I'd encourage people to try them and find out if you can find a way to get them into your room. An experiement with couch cushions and mattresses in corners can be illuminating. It all started there for me.

The comments in the GTG about the F20 are curious. I can't help but wonder if the F20 was used in a way that put it at an unfair disadvantage. Could it be that it needed a lower crossover point? I'm looking at doing something similar, but it only needs to get up to 40 Hz.

When I model the F20 in hornresp, I find that to my surprise I can get a bit more efficiency with a tapped horn of similar size (using different drivers). The tapped horn seems to need more careful filtering (HP) while the FLH has the sealed chamber as protection. The FLH also can go up a bit higher, but the TH becomes more seriously limited in the top end, and really only wants to be an LFE monster. Not a problem in my case because I have 18" pro woofers above 40, I'm just looking for a way to get more juice out of a pair of Rythmik 12" subs.

Again great work on this one Mike!

If i do decide to build it with the DCS380-4, i'll start a build thread and document how it goes. So you'll definitely be able to see how it works out. I'll also be happy to provide measurements, as long as i get some help with it... hopefully i'll be more up to speed by the time i finish the build, but i'm sure i'll still need some help with the measuring stuff.

EDIT:
lilmike, what kind of flare do you choose in Hornresp for this build? And is it the same flare that everyone uses for all of the diy horn sub builds here?

Is there an easy way to explain what the differences are between the three horn flare options(conical, exponential, and parabolic) and how they relate to the actual build? Hopefully, you understand what i'm trying to ask. What(or where) on your horn would you build differently when choosing a conical vs exponential vs parabolic flare?

Well I recognize those guys haha...Cant wait to hear your thoughts on these guys I know I loved em.

found any drivers that perform better than the standard model lately?

I may soon be building one of these, or similar, and comparing to a tapped horn of similar size with two Rythmik kits. That should be interesting.

paul, be sure to brace them well as in the updated build plan. no reason to lose any energy to cab vibrations. look forward to your build!

Antripodean is keen to build one, I'm keen to build something like this:

http://redspade-audio.blogspot.com/2...-horn-sub.html



I've seen a CAD drawing with the bracing and I'd be inclined to brace it a bit more actually.

Antripodean has some AE drivers (not the standard ones) that we might try in it. Maybe also a dual driver version. I need another pair of hands to do it so it should work out well, we both build the pair. We'd probably put on a bass GTG here, measure them and do a report. The Rythmik subs are very good on their own, I'm a bit curious what happens to them in a design like this. On their own they are equal to the best I've heard, only beaten in output. Do they simply get louder? Do they sound even better? Or do they lose something in being "turbo charged?"

I live near a train line where diesel trains go past in the evening sometimes. I might be watching a movie and hear this rumble. I'll pause the movie. Is it the movie or the trains? I can't tell the difference with the Rythmik subs.