4 18" 5400's and 8 passives "WOW!"

**robertcharles123** · **01-27-09, 02:32 AM**

Quote:

cinema mad wrote:

These monsters are/will be the best DIY sub twins around, in looks finnish and no doubt performance

......

Cheers....

Thanks for the vote of confidence. I am waiting on the granite and will be painting soon. Updates to come in the next few weeks.

Thanks,

Robert

**robertcharles123** · **02-05-09, 01:33 PM**

Granite has arrived. Paint is ready to be done.

**ISLAND1000** · **02-05-09, 05:23 PM**

THAT is Granite!

**cochinada** · **02-09-09, 07:47 AM**

This is truly a remarkable project in every aspect! May I ask how did you design those boxes, or what tool did you use, Robert?

Best Regards
Joaquim

**robertcharles123** · **02-09-09, 08:14 PM**

The boxes were designed by NEODan from the AVS Forum. He used sketchup.

Thanks,

Robert

**Warpdrv** · **02-10-09, 08:27 AM**

Quote:

ISLAND1000 wrote:

THAT is Granite!

And don't you take it for granite....

Nice lookin there Robert.... Haven't gotten to that point with mine just yet, but I'm doin the same thing...

**ISLAND1000** · **02-10-09, 12:35 PM**

Quote:

Warpdrv wrote:

And don't you take it for granite....

LOL, No I'm not . . . . it's just that . . . . this project is sticking in my mind. I dunno what it is, something uneasy going on here. I mean look at the equipment going in . . . . unbelievable! And then Robert has the temerity to have someone remove GRANITE from the face of the earth . . . . and install it on this project for a finishing touch?? Is he aware that granite is the base material from volcanoes?? What if, in the future, Robert is playing some DVD material with gobs of 5hz and 10hz tones played at over 100s of decibels and an actual volcano HEARS that stuff!!?? What if the volcano thinks it's a mating Call?? Has Robert ever thought of THAT!!!???

**robertcharles123** · **02-10-09, 12:53 PM**

Hey Island,

As a matter of fact, that suit of armor has been stuck in my head since I saw it. When you said that the bass can flip the lid on that guy, you started to make me wonder what is going to get "flipped" in my house. I have noticed a bunch of delicate things all of a sudden. We will see. I love that Sir Robert guy.

Good luck,

Robert

**ISLAND1000** · **02-10-09, 01:56 PM**

Quote:

robertcharles123 wrote:

I love that Sir Robert guy.

Yeah, sure . . . . that's what they ALL say! Poor guy. There he stands empty headed with nothing to call his own . . . . except maybe thin skinned . . . . or is it TIN skinned?

**cochinada** · **02-13-09, 05:52 AM**

Hi Robert,

I've read this thread from beginning to end but couldn't find your specifications for WinISD or any other program. I'm sure you did some modeling before the building or didn't you?

Since I'm in the process of learning and did find your project fantastic I would be very interested to be able to model it as accurately as possible. My guess for your box volume was 20,8 ft^3 but I'm missing some parameters for the PR (Audiopulse VMP) and some were actually invented as there is no information on the manufacturer site like VAS for instance. I choose an Fs = 10Hz and that's it. But apparently the plot of 'Transfer function magnitude' doesn't seem to be anything spectacular (F3 around 47Hz). I begun to mess with EQ filters but they didn't do much good so I stopped as I strongly suspect I'm missing something.

I would insert a link to my WinISD file for this if someone told me how to do it.

Thank you and best regards
Joaquim

**robertcharles123** · **02-13-09, 09:34 AM**

I modeled every driver out there and redid each system with and without PR's. This volume modeled ferocious. Big Decibels and low and flat. 2000 grams added mass to PR's. I never was able to get the graphs to go into the forum. I still have them saved, so maybe someone will be able to help with transfer.

Oh, box volume is right at 19.8 cubic feet internal for each cabinet.

Thanks,

Robert

**Jugix** · **02-13-09, 09:46 AM**

Quote:

cochinada wrote:

But apparently the plot of 'Transfer function magnitude' doesn't seem to be anything spectacular (F3 around 47Hz).

I only found audiopulse LMS-18 parameters and used their 18" PRs to model similar setup on unibox. All I am getting is +130dB straight line 100Hz --> 20Hz and after that it begins to decline!

**cochinada** · **02-13-09, 09:46 AM**

I've changed my model with your piece of information but I must have still something very wrong.
If you could email me your WinISD file I would be very thankful.

Thanks and best regards
Joaquim

**cochinada** · **02-13-09, 09:50 AM**

Quote:

Jugix wrote:

I only found audiopulse LMS-18 parameters and used their 18" PRs to model similar setup on unibox. All I am getting is +130dB straight line 100Hz --> 20Hz and after that it begins to decline!

I'm only getting a line straight also from +130dB but below 53Hz it begins to drop heavily.
I'm sure this doesn't correspond to reality.

**cochinada** · **02-13-09, 10:03 AM**

I did it! Here is my simulation:

4 18in 5400's and 8 passives.wpr

There is an icon for Attachments if you go to Advanced mode (clip icon). You must chose it, click Manage Attachments, select the file and upload it.
Then edit or write your post, chose this icon again and pick the file you have just uploaded. That's it!

I changed the Qms for the PR to 16 and it looks much better now!

**brandonnash** · **02-13-09, 11:09 AM**

Graph looks very good. Are you going to have any type of HPF at say 13 hz or below? Looks like the excursion really gets going past xmax after that. Of course that's running full power in room that would be somewhere around 125-130 db?? Other than testing and showing off you probably won't ever come close to exceeding xmax.

Either way it's gonna sound great and make neighbors wonder where the earthquake is originating from.

**cochinada** · **02-13-09, 11:15 AM**

Quote:

brandonnash wrote:

Graph looks very good. Are you going to have any type of HPF at say 13 hz or below? Looks like the excursion really gets going past xmax after that.

This is just my simulation as I don't know how Robert has done his. But I also noticed the problem with the driver excursion which only gets worse if you add for instance an EQ filter at 18HZ, Q=0,680 and Gain=6dB.
A HP filter at 14Hz would solve that issue I think...

**brandonnash** · **02-13-09, 11:40 AM**

As said before. I think the only way you would harm those drivers is with WOTW and a couple other movies running full bore. Even then I think you would run into your amp limiting or clipping before outrunning your xmech. It's gonna sound awesome in the most literal sense of the word.

**Jugix** · **02-13-09, 12:08 PM**

I think exceeding xmax problem is only theorethical with that setup so I wouldn't worry about that. Only thing what worries me is if your in-house copper cabling can handle the current without vapourizing them!

**redliner** · **02-13-09, 06:28 PM**

It looks like you're only using 2 drivers?

**brandonnash** · **02-13-09, 08:42 PM**

Yeah, You've only got 2 on there. It changes the response a lot when you throw another two in there. Looks like you'll need to double the enclosure size. Should help with the xmax though.

**robertcharles123** · **02-14-09, 12:23 AM**

First off, I made many attempts at modeling the subs.

1. I did 1 woofer and 2 passives in an enclosure, then 2 and then 4.

2. I layed each graph over the others and low and behold the only thing that changed was the sound pressure levels.

So, I made the box size the total volume of both enclosures, and used 4 woofers and 8 passives.

The power was set at 5000 watts input.

Like previously mentioned, the graph is basically a straight line from 200Hz-about 20Hz and then a gradual slope down -3 dB at 14.8 HZ and -5dB at 13.63 Hz

Parametric EQ set to 18 Hz Q of 1.00 Gain 5.0 dB.

HP Butterworth filter set at 15 Hz.

All of this was done with the 5000 watt input. The xmax was getting close at these levels.

I am currently going to run 2 Crown Itech 8000 amps on independant 220 volt circuits. I should have adequate power and control over the drivers. I also will probably never be able to test the total output of these guys as my home will probably be the limiting factor.

Any thoughts,

Robert

**robertcharles123** · **02-14-09, 12:33 AM**

Quote:

cochinada wrote:

I'm only getting a line straight also from +130dB but below 53Hz it begins to drop heavily.
I'm sure this doesn't correspond to reality.

I cannot seem to load the graphs you listed. I am trying to send you the graphs in email

**brandonnash** · **02-14-09, 12:40 AM**

I didn't read earlier, but are you putting in a separate electrical supply for it (breaker box or something)? Seems like that will draw a LOT of power along with putting it out.

**robertcharles123** · **02-14-09, 02:03 AM**

Right now, I have 95 amps at 110 volts available for HT. I am going to run separate 220 lines for the crowns and maybe a whole new service depending on difficulty.

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