Team-BHP - Normal and Reverse sub setting on HU ?!

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Originally Posted by low_bass_makker (Post 453762)

how can this possible....Team Bhp was created on 12th Feb 2004 how can Navin Ji post the info in 2002.....:)

Not on TBHP, LBM-boss. Just try google'ing and you will figure it out.;)

Guruji pahunche khiladi hain. Gyan ganga trilok ghoomke TBHP tak aayi hai, aur ham usee gyan ke alok mein pulakit ho rahe hain. (Completely OT sorry: )

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Originally Posted by DerAlte (Post 453915)

without googleing I think it was on diyAudio.com - audio projects by fanatics, for fanatics

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Originally Posted by DerAlte (Post 453557)

Question: where do I get something like a Variovent? There must be a more elegant solution than having to jerry-rig wire mesh and glass-wool.

Ok this is what I do....

I take a 4" dia (I think the real dia is a bit more but 4" dia is about right for starters). Then I chop of different lengths. Say 4", 6", 8". stuff each lenght with fiber wool. I change the stuffing to tune the bass. Once the stuffing and "right" lenght of tube is determined I wrap the whole stuffed tube in acoustically transpernt cloth (avaialble in black or white).

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Originally Posted by DerAlte (Post 453557)

postings (you know where!) dating back to 2002 on that subject! :)

I was thinking of making an ultra-small Ap... box (WDH 12"x14"x4-6") with a 10" woofer (haven't found a suitable one yet; is F3 less than 35Hz unachievable in this size?) to keep below the passenger seat in my Safari DICOR.

My first experiments with resistve ports (I did not know that they were called Aperiodic then) were in 1979-81. The driver in question was a 10" ENBEE (I suspect Bolton made them for ENBEE).

You are thinking of stuffing a 10" woofer in a box that is about 0.5 cu. ft. (14 liters). I dont think that is really advisable. A more detialed answer can only be known after the T/S specs are known.

If the Qts of the system is about 1.0, AP can help damp that to a more resoanble 0.7 or so. I dont think one should overdo this. F3 etc.. would again depend on the driver's specs.

AP is not a cure all. Other drivers (low Fs large Vas for example) might be better suited to a TL, others in bass reflex and still others in dipole. In all cases I find direct radiators offer better bass definition than indirect alignments like bandpass (4th or 6th order).

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Originally Posted by navin (Post 454123)

Navin Ji a little english here or people will get scared......:Shockked:

will try to convert the above in english at night.....

Quote:

Originally Posted by DerAlte (Post 453915)

Guruji pahunche khiladi hain. Gyan ganga trilok ghoomke TBHP tak aayi hai, aur ham usee gyan ke alok mein pulakit ho rahe hain.

This is seriously OT but have to ask you sir, are you originally from the Northern parts of India by any chance? Your knowledge of Hindi/Punjabi is very, very comprehensive & I'm surprised to see someone speaking/writing such fabulous hindi in today's world. Really feels nice to see people still taking the trouble of learning our national langauge properly and using it!

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Originally Posted by navin (Post 454123)

which 10 inch woofer you are planning to put in a .5 cuft box without knowing the spec of the woofer the correct enclosure design would be a bit difficult...

QTS is known as response of a speaker + enclosure.....the lower the qts lower end will be enhanced and if the qts is higher the sound will be punchy.....now if we introduce a AP (aperiodic vent) in the enclosure then there will be a source from which the internal air can escape thus altering the response of the speaker if the internal volume is small then by putting a AP we can alter the QTS

but again AP is not the final answer...but the result are better with passive radiators which are like same as sub but without motor assembly they tend to produce better defined bass...

LBM, and Gurus, I've changed my rear speakers to a JBL GTO 937.. The music sounds much better now..fast beats are now audible..but in songs like.."Billie Jean - Michael Jackson" where there is a secondary bass guitar..there is complete mayhem..we hear either a continuous boom or..too much noise.. I'm still not sure how to make the port..the local guy [not a professional installer] just tells me he'll do a hole for around 3 to 4" dia ..but am wondering if it will screw things up further..

I understand that the sub is a free air one..but i need to install it in my Gypsy..help please!! ANd thanks..i'm finding this thread very informative..

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Originally Posted by headers (Post 454501)

Hmmm I have just listed to the song one again the bass gutair you are refering will be a bit difficult for the 6x9 to produce....as it goes in the lowest of the freq spread. for this you will have to add a sub a 10 inch can also do the job..but it will elevate you budget.

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Originally Posted by vid6639 (Post 454670)

What happens if it's in a box? I just got 2 cars fitted with the 937 in a box.

Sounded pretty decent.

When it's free air how what happens?

I think the 937 (like most 6x9s) are designed for free air as they would be most probably installed in on a trunk deck.

If you stuff it in a box you will get a peakier response, a hump around 60-80Hz, and this can sound good. In free air it will go lower but due to the huge undamped trunk mght sound boomier.

In a box beucase the box is a small MDF box the response might have a hump or even a peak but the boom will be of a different kind (no trunk panel resonance).

Since you were talkig of a port I assumed the 937 was in a box.