Rule of thumb is wrong always. Without a frequency component it makes no sense. I too just model because all I care about is port noise, not ideal this or that.

I'm going to follow the min port area from the formula then plug it into a box design into winisd or leap and see what the mach turns out to be. I have a feeling it's going to be a lot lower then necessary.

Then I'm going to dance!

I think I need to find a manual generator to keep at the apartment as I sure as hell cannot keep a gas generator. Still no power since Saturday, getting by on the phone and a sneak peak at work.

Tried taking refuge at a local university? That's what a lot of people at SFA did after Ike tore through town, since the university had its own dedicated substation. No Holiday Inn but at least it has air conditioning.

Gas generator, could you imagine lol.

Get some 12v batteries and setup a UPS system, just have to find a way to charge batts first? Not sure how long this could last? Perhaps 20 or so 12v batteries in the closest?

I'm going to follow the min port area from the formula then plug it into a box design into winisd or leap and see what the mach turns out to be. I have a feeling it's going to be a lot lower then necessary.

Then I'm going to dance!

I do the same thing, port mach isn't even on the map, no need to worry if you get your area right.

I'm going to follow the min port area from the formula then plug it into a box design into winisd or leap and see what the mach turns out to be. I have a feeling it's going to be a lot lower then necessary.

Then I'm going to dance!

I do the same thing, port mach isn't even on the map, no need to worry if you get your area right.

Well I checked and the min formula works fine, offering a lot more port area then actually required. The 12-16 rule worked out fine too. At least in my situation.

I plugged two 15" xcons into winisd, 30hz tuning, 8.5ft^3 net for enclosure.

min formula, 15.28in port diameter, 0.04 vent mach.

12*8.5, 102in^2, 0.08 vent mach.

16*8.5, 136in^2, 0.06 vent mach.

Now the odd thing, 3 6" port diameters, which would be (pi*r^2)*3, 9*pi*3, 84.82in^2, yet I got 0.03 for vent mach. That's a lower vent mach then all of the above, yet mathematically it's less surface area. Unless winisd takes flares into consideration?

Normally you want the vent mach to be under 0.01, correct?

I guess on a good note, I never bothered to do any modeling with my latest enclosure, just tried to do as large as an enclosure I could fit.

Worked out quite well, plugged everything into winisd, Only way I could have gotten a little tad more in 40hz area is if I'd raise volume 2ft^3 and that's not happening (no more space!).

Anything less then my current volume and it didn't show any improvement in terms of spl, pretty damn linear actually, rising up to 30hz and plateauing.

Shit, I'm starting to sound like...

At least I'm using the right speakers in the right application.

I'm going to follow the min port area from the formula then plug it into a box design into winisd or leap and see what the mach turns out to be. I have a feeling it's going to be a lot lower then necessary.

Then I'm going to dance!

Of course it will be. Vent noise in a home environment on a midrange is WAY more critical than a sub in a car.

You are using strange units for mach...normally it is stated in m/s and would be way higher than what you posted.

Tried taking refuge at a local university? That's what a lot of people at SFA did after Ike tore through town, since the university had its own dedicated substation. No Holiday Inn but at least it has air conditioning.

This area is littered with universities and colleges, but they shut down until tomorrow I believe. But I retreated to my mothers massive house that I grew up in. Started construction in 1861, completed in 1863, major addition in 1888. That monster has withstood some serious stuff and has not broken a sweat. Not to mention, some how with exposed power lines and trees down everywhere, it still has power. So while my mother is in Germany for the month, I have a place of refuge if need be until power comes back in a day or two. Ferdinand is a little out of sorts, but he is ok.

I'm going to follow the min port area from the formula then plug it into a box design into winisd or leap and see what the mach turns out to be. I have a feeling it's going to be a lot lower then necessary.Then I'm going to dance!

Of course it will be. Vent noise in a home environment on a midrange is WAY more critical than a sub in a car.

Okay that makes complete sense, never dawned on me

You are using strange units for mach...normally it is stated in m/s and would be way higher than what you posted.

It's from winisd, I believe it's the percentage of mach.

If assuming correctly and I got 0.04 from winisd, then 0.04*344.8 m/sec = 13.792 m/sec.

Does that sound better?

Tried taking refuge at a local university? That's what a lot of people at SFA did after Ike tore through town, since the university had its own dedicated substation. No Holiday Inn but at least it has air conditioning.

This area is littered with universities and colleges, but they shut down until tomorrow I believe. But I retreated to my mothers massive house that I grew up in. Started construction in 1861, completed in 1863, major addition in 1888. That monster has withstood some serious stuff and has not broken a sweat. Not to mention, some how with exposed power lines and trees down everywhere, it still has power. So while my mother is in Germany for the month, I have a place of refuge if need be until power comes back in a day or two. Ferdinand is a little out of sorts, but he is ok.

Good to hear

I feel like crap. Called in late today. I think its a summer cold or something like hay fever. Combined with stress its shutting me down.

http://www.foxnews.com/opinion/2011/08/27/do-really-need-national-weather-service/

My brain just imploded

http://www.foxnews.com/opinion/2011/08/27/do-really-need-national-weather-service/

My brain just imploded

All I can do is laugh.

I feel like crap. Called in late today. I think its a summer cold or something like hay fever. Combined with stress its shutting me down.

Tanner feels the same way. Woke up every 30min all night long. Slept on my lap in the chair downstairs so the w could get some rest. Considering she is on her own all week that was the least I could do. Needless to say I am exhausted.

At 30,000' en route to San Jose. Have a fucking stop in SLC though. I hate and despise indirect flights, but direct was $1600.

You are using strange units for mach...normally it is stated in m/s and would be way higher than what you posted.

It's from winisd, I believe it's the percentage of mach.

If assuming correctly and I got 0.04 from winisd, then 0.04*344.8 m/sec = 13.792 m/sec.

Does that sound better?

Yep. Again, I always just design around the m/s. 14 is conservative, but not overly so

At 30,000' en route to San Jose. Have a fucking stop in SLC though. I hate and despise indirect flights, but direct was $1600.

Wave to me when you're taking off from SLC, I'll wave back

Waives