Flared port help

[mobeious 10+ year member]

lol ok if u say so

 

[SeanDub 10+ year member]

with more subs you can have each sub play a diff frequency range, they would have to be diff size subs, I had the chance to listen to a multi sub - substage at TC sounds, and it was amazing...

Not to bash you, but uh, how are you getting to install 18" LMS ultras? They should be taken from you immediately due to the above post. You think multi-sub setups with different size subs are awesome? You fail.

 

[newusername 10+ year member]

The LMS-5400 (and the related LMS-Ultra) has really, really low inductance. Just because it is LMS doesn't mean inductance is necessarily huge. If I remember correctly, the LMS-5400/LMS-Ultra has a full copper sleeve and a large shorting ring. Indutance and inductance variation is minimal...better even than some underhung drivers.

The LMS-5400/LMS-Ultra is simply the lowest distortion driver I have ever seen measured and every review I have seen of it has been glowing. I have an LMS-Ultra on it's way here and will let you know what I think of it, but the performance others have experienced speaks for the driver already.

As for other comments, the mass of the driver can be considered a bit of a highpass filter the same way that inductance is a bit of a lowpass filter. In this case, inductance is so low that your upper frequency extension is not a concern, and there is enough mass to give you pretty strong low frequency extension. Of course, the low frequency performance will mostly be dictated by your enclosure. The mass is relevant in that it is used to describe the driver's damping, but is not a significant limiter on the upper limits of your bandwidth.

You've got a great driver. The amount of port area will depend on the power you have on tap. I probably wouldn't even bother with a flared port as it will be tough to get the length of each individual port into the enclosure. I'd do a slot port with at least 100 square inches per chamber. It would be a lot easier, no doubt.

 

[mobeious 10+ year member]

 

[photocrazy8 10+ year member]

Not to bash you, but uh, how are you getting to install 18" LMS ultras? They should be taken from you immediately due to the above post. You think multi-sub setups with different size subs are awesome? You fail.

Idk how it work, but think Thilo knows a lil more than you....

 

[mobeious 10+ year member]

why just because he works at a subwoofer manufactor??

 

[SeanDub 10+ year member]

Idk how it work, but think Thilo knows a lil more than you....

He might, but you might not fyi. And even if he does he can still be wrong. Like you.

 

[photocrazy8 10+ year member]

why just because he works at a subwoofer manufactor??

He owns it, and is the engineer for all the subs...

 

[photocrazy8 10+ year member]

He might, but you might not fyi. And even if he does he can still be wrong. Like you.

I believe they were running a pair of 18's, a pair of 10's, and then a pair of line sources, it could have been geared more towards HT though...

 

[SeanDub 10+ year member]

I dunno. Whatever, you got your initial question answered. Your woofers are going to sound great because they are great woofers.

/thread

 

[IgnoreMe 5,000+ posts]

man, all this for a thread that was originally about ports...

either way to the OP. the 56% calculation was based on a specific amount of flare radius (i believe it was 1"). you can use devil drivers post over on soundsolutionsaudio.com if you want to see how to calculate the reduction of vent velocity using a specific flare radius.

a bigger flare will reduce vent velocity even more, and a smaller will do the opposite. either way, if you're going to use standard aero ports you can get away with about 50-60% less than a slot port.

Thanks Willd. So if my calculations are correct, the radius of the flare is 29/32", or .90625", yes?

this is a quote i found over at AVS regarding the 6" psp ports. so they do use a about a 1" flare which puts it pretty close to the above math. im using the quote because i have no gotten a chance to play with the psp ports.