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Audio Volume Problem


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#16 ScottSummerhayes

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Posted 31 July 2008 - 04:02 PM

If its 0guage thats great. You could get a T junction block to take an 8 or 4 guage cable to your new amp easily


Sweet, that would be the best as the power cable runs right next to the drivers seat (where i would fix the amp too)

the settings on the HU, have you used any of the high pass or low pass filters? You should.


Nope, EQ is Flat. No bass boost or anything like that. Nor any filters, how do i go about setting them up?

Your headunit is just pretty much running out of power hence the clipped/disorted sound, the solution is pretty much more power


Thought so much....

#17 redcab

redcab

Posted 31 July 2008 - 04:10 PM

Hello first post on EVO wahey.

"FLI Comp 6 intergrator (85w RMS / 90db)"

The 90db is the speakers sensitivity, this means how loud the speaker goes when fed with a certain amount of power, usually 1watt measured 1 meter away from speaker. If your stock speakers had a higher sensitivity rating they would sound louder at the same volumne setting. So 30 now does not necessarilty mean the same as 30 then.

Is this the reason why? obviously my 50w peak headunit is going to do 45w rms (prob about 20-25)

RMS = Root mean Square = 0.707 of peak value. 50w x 0.707 = 38.5w

hope it helps a bit

#18 1pukkadeal

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Posted 31 July 2008 - 04:28 PM

Hello first post on EVO wahey.

"FLI Comp 6 intergrator (85w RMS / 90db)"

The 90db is the speakers sensitivity, this means how loud the speaker goes when fed with a certain amount of power, usually 1watt measured 1 meter away from speaker. If your stock speakers had a higher sensitivity rating they would sound louder at the same volumne setting. So 30 now does not necessarilty mean the same as 30 then.

Is this the reason why? obviously my 50w peak headunit is going to do 45w rms (prob about 20-25)

RMS = Root mean Square = 0.707 of peak value. 50w x 0.707 = 38.5w

hope it helps a bit


was well worth making this your first post on evo :thumb:

#19 meekstaaa

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Posted 31 July 2008 - 04:28 PM

high pass filters filter the high signals whereever you want (set this on your head unit to your speakers)
Low pass filters filter the low signals (should be able to do this on your amp or maybe HU)

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#20 redcab

redcab

Posted 31 July 2008 - 05:02 PM

was well worth making this your first post on evo :thumb:


cheers mate, couldnt find anywhere to introduce meself so just jumped straight in.

#21 MC_Bob

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Posted 31 July 2008 - 10:01 PM

Whered you get that equation from? Its not even right? You cant even make an equation for that.

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#22 redcab

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Posted 01 August 2008 - 11:54 AM

Root Mean Square of a varying waveform is complicated but .707 of a pure waveform is a simple conversion coefficient.

Have I got the figure wrong MC Bob. Surely there is an equation for RMS values otherwise no one would be able to work them out!!!

#23 Squiz

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Posted 01 August 2008 - 11:59 AM

:roll: :D :thumb: Im with redcab on that one...
Its an industry standard to make sense of a complicated and varied subject.
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#24 MC_Bob

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Posted 01 August 2008 - 12:07 PM

The two values arent really related like that.

Peak values are trash and mean jack these days.

RMS is the power it can take constantly over a period of time with minimal degridation.

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#25 redcab

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Posted 01 August 2008 - 12:07 PM

"RMS" stands for Root Mean Square, and is a way of expressing an AC quantity of voltage or current in terms functionally equivalent to DC. For example, 10 volts AC RMS is the amount of voltage that would produce the same amount of heat dissipation across a resistor of given value as a 10 volt DC power supply. Also known as the "equivalent" or "DC equivalent" value of an AC voltage or current. For a sine wave, the RMS value is approximately 0.707 of its peak value.

googled it and found this...

I think it is audio manufacturers that confuse things by not adopting standard and straightforward specifications that are easily understood by everyone

#26 MC_Bob

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Posted 01 August 2008 - 12:10 PM

You can state your theory but in real life it has no use.

Anyone can copy and paste off wikipedia dude.

Edited by MC_Bob, 01 August 2008 - 12:11 PM.

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#27 redcab

redcab

Posted 01 August 2008 - 12:27 PM

pmsl not my theory Bob...its electrical theory

"The two values arent really related like that."

unfortunately they are related, totally related. Power = Voltage x Current. Average power = RMS voltage x RMS current, although when you start to include time (t) into the equation it does become to complicated to describe by me.

"Peak values are trash and mean jack these days."

Your right. They have always been trash, not just these days, an amplifer may only be able to deliver its peak power for a matter of milliseconds, peak constant power is more meaningful, but not used as it does not look as good on the box, and would dissapoint lots of people.

"RMS is the power it can take constantly over a period of time with minimal degridation"

Thats peak constant not root mean square of constant, and has nothing whatsoever to do with degredation of the signal.

You can state your theory but in real life it has no use.

Anyone can copy and paste off wikipedia dude.


fyi Bob i pasted it from

http://www.opamp-ele...ude_2_01_03.htm

and admitted I googled it, its a lot quicker than typing it, more to the point I understand it.

You should have a read, sorry to burst your bubble mate, but Im not making all this up.

I was just trying to help explain to the fella why some speakers are louder than others.

Edited by redcab, 01 August 2008 - 12:20 PM.


#28 MC_Bob

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Posted 01 August 2008 - 12:27 PM

Unfortunately its not. The fact that your equation up there ^ was wrong with the headunit. It has no use in this situation.

EDIT - Fwiw, I am aware of most electrical theories, but Im trying to say that although these laws are true and proved, some instances they cant be applies.

Edited by MC_Bob, 01 August 2008 - 12:28 PM.

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#29 redcab

redcab

Posted 01 August 2008 - 12:39 PM

OK Bob, I give in mate....I given all the fact and theory I can....I just cant argue with some who just says "your wrong" but doesnt say why.

Scottsummerhayes...Bob has not challenged my theory on speaker sensitivity (the 90db from me first post) so hopefully I have been of some help to you and you now know what to look for next time when trying to balance (match?) a system.

Peace love and goodwill to all men

redcab

#30 MC_Bob

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Posted 01 August 2008 - 12:42 PM

Common sense suggests it cant be right here. Even sensitivity readings arent accurate, do you know what distance and conditions theyre taken from? Freeair, ported, sealed?

Numbers arent the be all and end all, experience and understanding is.

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