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Old 10th October 2006, 14:47   #1
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Question How to find how much db My ICE puts up ?

Hi Techies,

I was reading through the thread on impact of loud music on infants & grown ups. I have often heard techies saying that they listen to volumes not more than 85-90db. My question is how can a normal person find out how much db he\she is listening to? I am asking coz my ICE as most of the aam junta is kind of more towards SPL than SQ. So how can I find out teh db levels so as to ensure that I am not listening to dangerous levels ?

Techno
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Old 10th October 2006, 14:49   #2
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If you have to shout to make yourself heard it is too loud. The volume should be similar to normal conversation.
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Old 10th October 2006, 14:55   #3
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Ok thats about the loudness part, what about how to find out db ? is there a simple conversion based on wattage etc? sorry if it sounds dumb but I would rather ask than be dumb

Also if what you say is correct you should never need an amp, a set of comps in front & 6X9 at rear should do and the current day HUs IMHO have enough power to fire them at conversation levels

Last edited by Technocrat : 10th October 2006 at 14:58.
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Old 10th October 2006, 15:14   #4
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Techno, amps are not for higher sound levels. they are for better sounds. this is the way i look at it, i am an absolute novice here. B&T & navin might give the technical info on these.

on a low output system, have you realised anytime that the best blend of the music comes out only when you turn up the volume ? similarly, i think what the amp does is to amplify those sounds to give you a good output at normal hearing levels.

i hope i haven't sounded stupid. thanks
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Old 10th October 2006, 15:18   #5
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I agree with you EL but I believe at conversation levels the Hu does a decent job(IMHO but others may differ ) its only at slightly higher levels that amps help in maintianing teh clarity & crispyness of the sound.

Anyways this was just part of my question, I want to know how loud is bad(Sorry Navin but your answer is very open ended ) & also how can I find out the db levels in my ICE?
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Old 10th October 2006, 16:47   #6
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this is a comparison chart for the db scale....for the music there is not a single value it has a lots of peaks and dips but the max value can be taken also....for measuring the db scale accuratley we need to play sine waves to achive the figure.....what is the system is capable of....

to measure we need db meter....
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Old 10th October 2006, 16:49   #7
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Hmm pretty much on Navin's line but I guess this ones a lot clear. Thanks LBM
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Old 10th October 2006, 16:54   #8
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The ear is not linear. Sound pressure depends on the components used (amp and speakers) the insall and the listening position and even then reading would depend on the freq sepctrum used.

You can get a db meter (C weighted or A weighted) and these will give you an average SPL reading over the freq. spectrum as dictated by the weightage (A, C, etc..). The general accepted guidelines are that prolonged exposure (greater than 30 min) to sound above 90-95db can begin to get harmful.

Given that measuring SPL is not really an exact science (not a lot related to audio really is) it is best to realise then that our vocal chords evloved so as to allow us to speak clearly and be heard clearly without damaging another's hearing. it can hence be deduced that if you have to shout to be heard your music is too loud.

Within it's "pass-band" (generall accpeted to be 200Hz to 6000Hz) the human ear is very sensitive and accurate. Alll we need to do is use it.
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Old 10th October 2006, 18:40   #9
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Quote:
Originally Posted by Technocrat
what about how to find out db ? is there a simple conversion based on wattage etc? sorry if it sounds dumb but I would rather ask than be dumb
Not dumb at all, good question. I see that Navin has answered it quite well, and let me do some deciphering here.

SPL can theoretically calculated with reasonable degree of accuracy. For that, you will need to know the SPL of the drivers (or better still the system), and the power input to them. Based on sensitivity at 1W/1m, you can increase the spl by 3dB for every doubling in power, for the same distance. Once you know the system spl at X watts for 1 meter, you can now calculate for the distance required by subtracting 6db, for double the distance, or adding 6dB for half. This way you can achieve the theoretical SPL. But in reality, the effect of the room, cabin of the car, speaker placement etc. will differ from theory. For such situations, a SPL meter is best. (You can get one at Radio Shack for $25 or something)


Quote:
Originally Posted by esteem_lover
on a low output system, have you realised anytime that the best blend of the music comes out only when you turn up the volume ? similarly, i think what the amp does is to amplify those sounds to give you a good output at normal hearing levels.
This is due to the ear's listening pattern. Like Navin said, the ear isn't linear, and is more sensitive to frequencies around the mid-band.

This is also the reason why head units have 'loudness' as a feature. The idea of the 'Loud' function is to boost the lows and highs without altering the midrange, so that at low volume levels, frequencies that are not distinctly audible to the ear become fuller.
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Old 10th October 2006, 19:00   #10
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Quote:
Originally Posted by Bass&Trouble
This is due to the ear's listening pattern. Like Navin said, the ear isn't linear, and is more sensitive to frequencies around the mid-band.

This is also the reason why head units have 'loudness' as a feature. The idea of the 'Loud' function is to boost the lows and highs without altering the midrange, so that at low volume levels, frequencies that are not distinctly audible to the ear become fuller.
coool B&T , now i get the idea...
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Old 10th October 2006, 19:01   #11
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Thanks a lot Navin(This one was clearer ) and B&T.
Hmm Now I have an idea how loud should be bad. Now all that I need, is to find some one who has SPL meter to get the db ratings for my ICE(just want to know)

btw this is my current ICE stup colourfull isnt it

Just need to get teh db figures for this setup

Last edited by Technocrat : 10th October 2006 at 19:07.
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Old 10th October 2006, 19:14   #12
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how is the sub mounted

box or IB ?????
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Old 10th October 2006, 19:16   #13
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Ported Box in Alto's Boot below the rear tray on which the rear speakers are placed.

Last edited by Technocrat : 10th October 2006 at 19:18.
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Old 10th October 2006, 19:19   #14
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Quote:
Originally Posted by Technocrat
Ported Box in Alto's Boot
from where did u made the ported box....which ports are used....any pics would be help full.....
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Old 10th October 2006, 20:51   #15
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Quote:
Originally Posted by Technocrat
btw this is my current ICE stup colourfull isnt it
technocrat,this is really a technicolor system
U got all the basic colours,blue,red and green!!!!

BTW why dont u do the way B&T has suggested or ask LBM to courier his SPL meter for few days.He is our residant SPL expert here..
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