Lilmike's Cinema T-6 - Page 2

A dayton classic 10. Is there an amp that would be better that wouldn't cost $200?

"I'm running really cheap midbasses..."

ah man lilmike, you deserve better! put a $20 spot on your plans and nobody will complain, they are all good...if i built one of your horn subs, i'd have zero issues shooting you a $50 spot (well, that is because i would build multiples...:-))

for a good main, check this out:
http://www.avsforum.com/avs-vb/showt...6#post20908406

Thanks for the reply. Is that 8 db based on a hornresp sim or actual measurements? I ask because I have wondered how accurate the sims are in terms of efficiency. I recall someone saying it over-estimated efficiency, not sure where. Might have been volvotreter. When I simulate a driver without a horn in hornresp (0.1cm long horn matching driver SD), it seems to be a bit optimistic on 1w1m. I would like it to be right, but is it?

Did you enter the correct voltage?

applause from me.... I only stop by on occasion and saw this thread.

way to go mike...

Yea, I remember you buying out the last of the 55-1740's. Not bad for what they are, I think I've gotten my $15 out of each one.

hey mike,
I am having a problem finding the w8-740c but I have found the w8-740P and didnt know if that would work as I do not know the difference between the two.

I have also found plenty of dayton 8" drivers and the classic is a little cheaper so I may go that route.

However, I still may go with a 10" as there are some that are in the same price range as some of the 8s and if that gets 6db more than what I have already that could really rattle the bones...

This is the 10 i was looking at,
http://www.parts-express.com/pe/show...number=295-202

what do we have for good 100wattx2 pro audio amps for using two of the DCS255-4 on the cheap? I guess I could always use an old receiver and use direct inputs to drive the subs as this would provide 100 watts to both easy enough.

Also since this is a much cheaper build, would we be able to use a car audio type inline high pass instead of having to go the minidsp route like I did with the F20s or should I just bite the bullet and get a 2x4 minidsp for eq and highpass, etc

Yea that is what my goal is to have 2 to start out with and maybe add a third in a back corner. Hence I am on the fence about starting with 10s or 8s as the 8s will be slightly cheaper. However, I can say that i have narrowed it down between the two dayton classic drivers.

I certainly don't expect it.

That's a good result in terms of the accuracy of the sims vs measurements. Good to know. I have some builds coming up at some point that will be large, too big to do test boxes. I'd hate to expect 96 db then actually get 91! Some Rythmik 20 Hz tapped horns under the floor coming in through corner openings, dual 12" drivers. Planned for a long time, still need to get around to it.

So the JBL GTO 10" will work in this enclosure? Just alter the width?

Great plans by the way!

Question.. Is this Cinema T-6 a little version of the Cinema T-20?

With the higher tuning of this enclosure I bet this would make for a great Car Audio sub.

Thanks for documenting this. I posted a reply in Erich's flat pack thread wondering if we could get this flatpacked.

This is my very first post. I'll keep it brief:

Lurking here for a few months, lilmike has taught me most of what I know about tapped horns.

This design has finally provoked me to cut wood.

I modeled most of the 10in drivers on the list in post #2, and chose the Fi Audio X10 both for price ($109 direct) and because it looked the flattest in hornresp.

While I'll probably go with this driver anyway, the flat response was due to entering Sd incorrectly (338 vs 310cm2) and for lack of an Le spec, using 3.2mH instead of the real spec (which I got from them via email) of 1.75mH.

Plugging in the real specs, this driver looks pretty much the same as the rest of the 10s.

HOWEVER, adding an extra 3-4mH and an extra 0.05Ohms impedance per mH, makes this look SUPER-flat.

This begs a question for the advanced Hornresp user, and anyone who's compared actual measurements with modeled response:

Since the added 4mH series coil is essentially a 159Hz low-pass filter, (assuming average 4Ohm impedance for the driver,) and this resulted in a MUCH flatter response at the low end, will using a 1st order low-pass filter in the real world, in lieu of this inductor (via DSP, etc,) similarly flatten the response???

Will using a "serious" low-pass filter further flatten the response down low? (18 or 24db/octave via DSP)

Have I been overly critical and nit-picky looking for a VERY flat response down low in hornresp models, or is the roughly +/- 3db waviness most of these 10's show in lilmike's T-6 good enough to flatten out provided the finished cabinet is fed signal only in the pass band?

Short of stepping up the the complexity of akabak, is there any way to coax hornresp to model anything but a full-range signal?

Any guidance appreciated.

THANKYOU LILMIKE for all of your hard work, encouraging MANY people like myself to get into this hobby.

Eric.

Would the kicker 10" in this add work for this enclosure?


http://app.streamsend.com/c/14849105...eCarStereo.com



Considering 2 to supplement my current set up..
And at 80 bucks seems like a great deal...

lilmike, thanks for the reply! This is fun.

I gather several kernels from your thorough response:

1. Most importantly, given the plot attached, as well as your observations thereof, adding a low-pass filter, in this case an actual inductor, has a frequency-dependent response, attenuating where's it's supposed to (above the pass-band) and not so much where it's not (quite a bit of loss there too it seems,) but doesn't alter the basic "shape" of the response anywhere.

2. The question still stands as to whether there is a way to feed hornresp models a limited frequency band for modeling.

3. The standing question may be moot, given the uniform behavior of the model lilmike posted in the pass band, with a real low-pass filter.

4. Stop asking questions, order the drivers, cut wood, smile.

Edit: Sun pm: I wasted a trip across town to wheel a backup sub cabinet into place... It seems it's possible to fry a "4000W RMS" driver with ****** dj signal when driven by 1600W RMS. Nearly $300 each to have original EV MTL-1x drivers re-coned, (parts + labor,) $800 for a new pair, or another $250 for a pair of crappy Chinese 18in subwoofers, which lasted a whopping 4 months. I'm ready to kick them to the curb (they never did anything south of about 45Hz) and go with 4x lilmike's T-6 cabinets. The 3 hours it took me to shave the speaker reliefs, (manually, with a utility knife,) and grind the pole plates (!!) to fit the Chinese pair into the MTL-1x cabinets, would have been MUCH better spent cutting new wood for a new alternative.

The EV MTL-1x is well-regarded as a good "PA" sub. Maybe it's good for live sound reinforcement, but it's awful for recorded music, ala DJ's spinning.

I thought I recalled being disappointed south of 45Hz, but it looks more like 55Hz from EV's published response plot for these. (attached, if I can do so with a post count of TWO.)

While there are few ways to make live sound south of 60Hz, (harmonics of a bass guitar, pipe organs, synth bass are clear exceptions,) playing recorded music, in a DJ setting, calls for the same class of gear we enjoy at home... just able to play much louder. I see no reason why a great design like the T-6, which makes the most of a single sheet of wood, and a class of driver that's readily available, cheap, and handles huge power (relatively speaking) can't make an excellent "PA" sub for DJ'ed music.

Four of these cabinets, given thermal and excursion limits, seems to blow even a pair of EV MTL-1x cabinets, (which I can't fit into the corner I need to fill,) out of the water, while extending usefully 25Hz farther south. Instead of driving a single cabinet with TWO nice Crown MA2402's bridged mono, (1600W at 8ohms to each driver,) I'll use one amp to drive all 4 cabinets, (800W at 8ohms for each pair,) cranking out the same SPL, with MUCH lower extension. If I fry drivers, I'll replace, or even recone them... I'm still waiting for an answer from Fi about what re-coning costs for these, their cheapest product. (BTW, while these amps are capable of driving a lower impedance load, with more power, listening proved they sounded best with an easy 8ohm load. Damping factor increase responsible?)

An added benefit to likmike's T-6 design, using the side-mouth variant, is that the gang of 4 cabinets fits into a very small space (72h x 48w x as shallow as possible... 12-13in) under existing flown cabinets, and allows all 4 mouths to be ganged together at gut-height for woofer surfing, a popular sport on any club dance floor.

Again, these seem to offer a very good compromise of low build effort, low extension, max output, efficiency, value. I've been trying to fill this magic corner, (in which I'll also experiment with corner-loading, but this doesn't offer much "surfing" potential,) for 6 months, and this is the first design where I could achieve the SPL I'm looking for in the alotted corner space within a reasonable budget. Just like Danley designs his cabinets to be an integer divisor of a semi truck load for efficient transportation between gigs, a stack of 4 of these T-6 cabinets fills my corner perfectly, with no wasted space. Plenty of other designs discussed here, and on other DIY forums looked great, but I couldn't fit enough of them in this corner to fulfill my design goals. (I even considered stacking 8-9 Insubnia Anarchy boxes!)

4 of these, built with the Fi X10, model with an efficiency of about 97dB/1W, which pretty much exactly matches my top boxes.

I've yet to find anyone back the idea up with a credible study, but "rumor" has it that juicy sub-bass, south of 50Hz, makes bar patrons want to drink more, whereas sparking highs make bar patrons want to urinate more. Our top boxes run out of gas at 16khz, and I'm fine with that

The last benefit of this experiment is that if they don't work out at the club, just like a retired draft animal, these will find their way home to pasture, where they can retire comfortably on a diet of mildly-amplified vinyl, and the occasional action movie.