[kb100]

Originally Posted by Vivekphadnis

KB100, what is this chap's name? I would like to meet him someday.

Vivek... Its some Joseph or something.. I will get you the exact name... He is a Keralite (I hate the term "Mallu" !) .. and an ex employee of Brooke Bond..

Extremely knowledgable.. but tempermantal; - as most geniuses tend to be..

This man has even DESIGNED/INVENTED coffee/tea drying machines!.. and a bunch of other things... very prolific...

[Autophile]

Originally Posted by low_bass_makker

I happen to listen the above install myself. VVVVery good job done nice stuff clean and neat. On thing I wanna ask that the port intalled in the enclosure is just next to the wall. Which I think is not right, rest other knowledgeable person on this fourm like I said earlier "please shed some light" on this topic.... What I have learnt is below.Taken form a port manual.

If you were using a 4 inches diameter port keep it 4 inches from the bottom of the encloure and 4 inches from the enclosure walls. Also I am not talking about tunnig of the port so dont go in to that context please....... I am talking of installation only.......

LBM, i would like to ask you a practical question related to above post of yours?

Can you design a 43 Litre box for a 15" Subwoofer with a port with 3" internal dia with 11" length in some other location. If yes let me know the design.

Its not a technical question for you its a practical one. I am not talking about technical aspects of port tuning, port gain, noise etc etc.

[low_bass_makker]

Thanks man U must busy doing more good installs, Keep it up man U are really educating people about sound in car.....

Any ways about the Enclousre we can make it with the specs of 17 x 17 x 13 ( 1.59cuft or 44.9 ltrs )where the sub is ont he 17 x 17 face and the port goes on the top like u have done in the vega, here is a pic of the same....




Here the port will be facing the roof of the car ....

Rest now I hate to add this that there will be a little port noise if the sub is tuned at lower freq or played at lower freq also.......

rest I am also using the above design in my swift and it is working ok....

[kb100]

Originally Posted by low_bass_makker

If you were using a 4 inches diameter port keep it 4 inches from the bottom of the encloure and 4 inches from the enclosure walls..

LBM... Agreed that the port it firing to the roof.. other than that and perhaps the volume, I dont see you as having achieved what you said (quoted above) in the picture of the box you are currently using..

Secondly GURUS... I thought to port should ideally be on the same plane as the sub.. in other words if the sub is mounted horizontal to the ground.. then the port also needs to be horizontal - venting either forward.. or to the rear ... (you can then play with placement distances to add/reduce bass effect - in other words BOUNCE the sound ... if placed in a corner will have a "HORN" effect) ... The Design Drawing posted by LBM also indicates this.. I was under the impression that any other placement - like the 90Deg one LBM has used, is sub-optimal?? (lol)

[low_bass_makker]

Originally Posted by kb100

LBM... Agreed that the port it firing to the roof.. other than that and perhaps the volume, I dont see you as having achieved what you said (quoted above) in the picture of the box you are currently using..

Sir I did not understand what u said here .The pic above is a pic taken from the vega install done by autophile him self..... In that setup the sub were in the boot and the ports were firing in to the cabin........wait i will show u the complete pics......








And the box volume is 17 x 17 x 13 which make the internal volume to be 44.9 liters. In which we will have to deduct the port volume and the sub displacement which will come to nearly to volume jb has asked.......

Also the port should me on the speaker side but in some situations port can be on the different side also.......


If any doubt please ask.......

[navin]

for the low bass port placement is not very critical esp for the front listeners.
see...http://www.trueaudio.com/st_ventq.htm

[low_bass_makker]

Originally Posted by navin

for the low bass port placement is not very critical esp for the front listeners.
see...http://www.trueaudio.com/st_ventq.htm

I like it we much................ clear and simple explalation of the ports......
KB Sir where are u..........

[Bass&Trouble]

Originally Posted by Autophile

Can you design a 43 Litre box for a 15" Subwoofer with a port with 3" internal dia with 11" length in some other location. If yes let me know the design.

Its not a technical question for you its a practical one. I am not talking about technical aspects of port tuning, port gain, noise etc etc.

One could get a slot port of the required dimesions into the 43 litre box and yet have the end of the port 3-4" away from an opposite surface. Another option is, of course, to have the port protrude out of the box, even partly so as to allow adequate space at the enclosed end of the port.

However I think LBM is trying to more specifically curious about why the port is as close to the side wall as it is.

kb, there is no issue with having the port and the sub in different planes as Navin pointed out. There are zillions of home audio speakers that have rear-firing ports, and the only issue with them is that you can't have the speakers right against the walls.

[kb100]

Originally Posted by Bass&Trouble

kb, there is no issue with having the port and the sub in different planes as Navin pointed out. There are zillions of home audio speakers that have rear-firing ports, and the only issue with them is that you can't have the speakers right against the walls.

My question is can the port be 90 Degrees to the speaker... in other words... Can we have a down firing woofer with a horizontal port? .. and is it OPTIMAL?... I did acknowledge the rear firing bit.. as a matter of fact my home speakers - which has peerless drivers - have rear facing vents..

@LBM... Sorry man .. am forced to work someties - for my living!!.. I meant your box did not seem to have been built as per the 4 inches rule quited by you either ... that was the original question na...

[Bass&Trouble]

Originally Posted by kb100

My question is can the port be 90 Degrees to the speaker... in other words... Can we have a down firing woofer with a horizontal port? .. and is it OPTIMAL?... I did acknowledge the rear firing bit.. as a matter of fact my home speakers - which has peerless drivers - have rear facing vents..

Anything between 0 degrees to 360 degrees is just as optimal. So that includes 90 degrees. Again, there are zillions of speakers using passive radiators at 90 degrees to the main subwoofer driver, but not as many with side firing ports, maybe because it looks ungainly in additon to corner loading blah blah blah.

LBM, I am foxed. You ask "What do u want Omlete or Butter Chicken ?????"

Does this imply that...

a. This is some form of advertising for a soon to be launched dhaba?

b. You have joined the bandwagon of the likes of Sanju Baba and Fardeen Khan, screaming themselves hoarse about the virtues of Indian poultry?

c. You are waiting on me, and if I were to place an order, you would arrange to have it home-delivered?

d. Vegetarians should starve to death since they cannot eat either?

[navin]

SOT: Is not Omlete spelled "Omlette"! :-) LOL

Location of port makes little difference as it the Fb of the box we are changing and Fb is not sensitive to port location.

[Sam Kapasi]

last i checked it was Omelette.What's this all about LBM?

[kb100]

Originally Posted by Sam Kapasi

last i checked it was Omelette.What's this all about LBM?

LBM.. Take a bow... You got THE teaser hisself interested!!

[rsjaurr]

Originally Posted by Bass&Trouble

. Vegetarians should starve to death since they cannot eat either.

Even somebody like Kb and gunbir should also avoid both as these have very high fat content.

Even o/w gunbir is not going to eat omlete....sorry omelette made at LBM's dhaba!

[kb100]

Originally Posted by Bass&Trouble

c. You are waiting on me,

Maybe he wants to "serve" you .. Now that is One omelette I want no part of!!