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Discussion Starter · #1 ·
So I seen this method recommended a few times in other forums and was bored the other day and decided to try this.

is it just me or is this method not the worst possible thing to be having people do?

I was quite happy with my setup before (done by ear) but always looking for that small step up and will try almost anything:eek:

anyway, it sucked!

thanks for listening.
 

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what is your frustration with this professional method, may I ask, Mister MuTT?
 

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Well... "it sucked"... there you have it.

LOL.

If you would care to explain why you felt it sucked I might be able to address your concerns or answer your questions about it. Most people who say "it sucks" didn't do it right... and they usually screw up the part about setting your volume at 3/4 or using an appropriate test tone recorded at 0 dBfs.

Manville Smith
JL Audio, Inc.
 

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Discussion Starter · #5 · (Edited)
using an alpine d300, running optical to an H701, volume goes to 35, had it at 28.
tones recorded at 0db 50hz for subs, 100hz for midbass and 1khz for mids (wasnt going to touch my tweets.)

on my recently calibrated voltmeter, I set all the voltages to almost exactly what the tutorial recommends +/- .1v

had the tutorial printed out and did it to a "T"

when complete my system sounded like bum, like everything was over driven, unbearable to listen to at a volume of 16. not sure what I did wrong...but please let me know what to try.

Edit: I'm using JL slash amps and am happy with them, no need to get so defensive, I tried it and didn't like it. it happens, personal taste I suppose.

2nd Edit: I do have a setting on my 701 that has no settings, no EQ, xovers wide open, no T/a, no anything...
 

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Sure you did the calculations correctly? Just checking

I don't see much harm in the program. I used to use it all the time and never had any bad experiences with it.. though it's been a while.
 

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Discussion Starter · #8 ·
I've tried that as well, like I said, I'm happy with where there are and have been, just having fun trying new stuff, the JL by far gave ME (<--please note personal reference) the worst results.
 

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Discussion Starter · #9 ·
Sure you did the calculations correctly? Just checking

I don't see much harm in the program. I used to use it all the time and never had any bad experiences with it.. though it's been a while.
not sure what there is to calculate, my speakers are 4 Ohm and sub is 3, even measured impedance before I started just to be sure.
 

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Most of the time people don't like it because they feel it's leaving too much power on the table.

I thought about trying it once but I'm happy with the results I get using my ears.
 

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not sure what there is to calculate, my speakers are 4 Ohm and sub is 3, even measured impedance before I started just to be sure.
JL tells you to set voltage by using ohm's law:
V=(resistance*power wanted)^1/2

You want 800w @ 4ohms? 4*800= 3200
3200^1/2= 56.6 volts


I'm betting you know this, but I want to make sure.
 

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The link I posted is a very good reading imho.

Learning to do it by ear is not that difficult... and it is, again, imho, entertaining... ;)

1. get a test tone... 200 or 500Hz
2. set all your head unit and amp controls to flat
3. disconnect all the speakers
4. wire a couple of identical speakers in serie to the one channel you want to set
5. put earplugs, please
6. take the head unit volume up until you hear clipping... it will change pitch... it is noticeable, don't worry
7. take the volume knob one or two steps back
8. take the channel gain up until you hear clipping

You get the idea, I do hope!


Cheers,

MO
 

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Discussion Starter · #14 ·
JL tells you to set voltage by using ohm's law:
V=(resistance*power wanted)^1/2

You want 800w @ 4ohms? 4*800= 3200
3200^1/2= 56.6 volts


I'm betting you know this, but I want to make sure.
Problem is probably just me, I don't care about watts at all, I don't look at them or judge equipment based on watts.

and yes, I know what you're saying and thank you for the clarification.

problem is, when I go to a show and someone wants to listen to my car, I have it set so that even if some bonehead turns up to full, I don't need blown speakers, so I'm probably setting mine on the low side not getting the most out of my amps yadda yadda, but it's the most out of my speakers I'm more concerned with....I have a 1500 watts hair dryer at home, but to be honest, it sounds like ****.

while doing step 9 of the tutorial, I wound up with everything back down to where I started from.

my system isn't loud by any stretch, but sound most natural with the volume at 25.
 

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Problem is probably just me, I don't care about watts at all, I don't look at them or judge equipment based on watts.

and yes, I know what you're saying and thank you for the clarification.

problem is, when I go to a show and someone wants to listen to my car, I have it set so that even if some bonehead turns up to full, I don't need blown speakers, so I'm probably setting mine on the low side not getting the most out of my amps yadda yadda, but it's the most out of my speakers I'm more concerned with....I have a 1500 watts hair dryer at home, but to be honest, it sounds like ****.

while doing step 9 of the tutorial, I wound up with everything back down to where I started from.

my system isn't loud by any stretch, but sound most natural with the volume at 25.
The main purpose of the JL tutorial is to set the amp gain for the appropriate power. IMO, it's really for people who are new to car audio and don't realize the implications of clipping.

In that case, then I agree with this:
If you just un-level-matched your system, of course the levels won't be matched. Is that the problem here?
I was going to suggest that is the problem, but wanted to make sure you were doing the calculations correctly.
 

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Just use your ears and not measurement tools set gains....you can hear when the amp is starting to strain then turn it back some. If you get to a point of satisfactions without reaching the limits, just stop and be happy :)
 

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Discussion Starter · #18 ·
Just use your ears and not measurement tools set gains....you can hear when the amp is starting to strain then turn it back some. If you get to a point of satisfactions without reaching the limits, just stop and be happy :)
exactly where I'm at.....I just like to fiddle and try everything ya know.
 

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exactly where I'm at.....I just like to fiddle and try everything ya know.
I got you...i say it because i personally used the JL tutorial exactly as stated then i decided to do it myself and ended up with far better results. My personal opinion, it sucks :eek:
 

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The purpose of the procedure is to set the baseline levels of each channel bank for clean output.... THEN, you need to turn down any amplifier channels that are too loud in order to balance levels as needed for tuning purposes.

Using your PXA-H700... which goes to 35, you should set your volume to 26, not 28 (35 x .75 = 26.25). Then, the full level sine waves will reach clipping level at that level, which allows for some gain overlap (roughly 10-12 dB) which is necessary for there to be sufficient output in the system. If it's not loud enough for your tastes, repeat the process with the volume set at 60% or 65% of full output (Volume 21 or 23) which will give you more gain overlap.

As someone else mentioned, the method is simply designed as a way for people to achieve repeatable, accurate gain setting results using simple tools that are generally available and it works very well for that purpose. It's a lot more accurate than setting by ear or using a scope with no load on the amp.
 
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