Misc Questions...

[KenSchoen]

Hello all,

I have a couple questions about some of the finer points of car audio and I'm hoping to learn from the best

1. How important is the port size....I've heard 12-16 square inches of cross sectional area per 1 cubic feet of box size. Is this the right way? If so what is the gain?

2. I've always used round flared port's but its hard to follow the above rule if it's important to do so...Are there advantages/disadvantages to round/square/slotted ports?

3. What are the biggest audible differences between component's and running bullet tweeters and seperate midrange speakers?

4. I know bullet tweeters are meant to be loud but I would imagine there must be some quality there too. Would they be as clear as something like a middle of the road component set?

5. steve meade himself runs components and two subs in addition to his 18's....if someone where to do this....what would the crossover points be set at?

I may post more questions when these are answered. Thanks everybody

[islandpride684]

1. Yes

2. Yes

3. Passive and active

4. Refer to #3

5. Refer to #4

and last but not least...too many damn questions to answer in one post...a little tip, try to stick to one topic and learn about that rather than trying learn about a lot at one time...

[KenSchoen]

Ok what are the differences in sound quality between bullet tweeters+midrange speakers and similarly priced components?

[Krakin]

1. Port per cube is wrong.

It once worked partially when speakers didn't have large amounts of excursion.

To find port area this is a pretty reliable calculator:

http://www.carstereo.com/help/Articles.cfm?id=31

This is a great thread on port area:

http://www.stevemeadedesigns.com/board/topic/189867-understanding-ports-a-lesson-in-dimensions-vs-efficiency/

2. For port flaring this thread is very helpful.

http://www.stevemeadedesigns.com/board/topic/188594-you-may-be-kerfing-all-wrong/?hl=+you%20+may%20+kerfing

This is a great website on ported enclosures as a whole, but mainly ports:

http://www.subwoofer-builder.com/flares-25mm.htm

3. Mainly the sensitivity is much more in PA equipment.

4. You can get PA to sound good, but there is much more effort involved than component sets.

5. Crossover points are a fairly delicate subject, I set my crossovers based on the first edge diffraction points of my speakers.

[KenSchoen]

Thank you so much for you response and help I really appreciate it.

3. Mainly the sensitivity is much more in PA equipment.

4. You can get PA to sound good, but there is much more effort involved than component sets.

So these http://www.rockfordfosgate.com/products/details/pp4-t and these http://www.rockfordfosgate.com/products/details/pps8-6 are considered PA's?

And this

5. Crossover points are a fairly delicate subject, I set my crossovers based on the first edge diffraction points of my speakers.

Was all greek to me haha.

[RooTxBeeR]

I used

http://www.carstereo.com/help/Articles.cfm?id=31

before and it told me 176sqin of port for a single 15. I loled

[Krakin]

I used

http://www.carstereo.com/help/Articles.cfm?id=31

before and it told me 176sqin of port for a single 15. I loled

Do you understand the physics behind proper port area?

[RooTxBeeR]

I used

http://www.carstereo.com/help/Articles.cfm?id=31

before and it told me 176sqin of port for a single 15. I loled

Do you understand the physics behind proper port area?

nope. But almost 180sqin for one 15 is crazy! Never seen that before for a regular ported box

[Aj11]

yes that's wayyyyyyy to much!

i know of several who have 2 18s that are around 120sqin

[Krakin]

Then how do you know it is too much of you don't understand the physics that proves it does? Unless you can prove that the formula Small came up with for this is wrong, don't tell people to not follow it.