Hey guys,

I've tried hunting down people's JL 300/4 settings online, but have failed each time I've tried... I'll lay out my system, and maybe you guys can tell me if I'm doing something I shouldn't be doing...

H/U: Alpine CVA-1006
Fronts: CDT CL-61a
Rear: Infinity coax
Sub: JL 10w3v2
Amp: JL 300/4 (fronts and sub)
EQ: Alpine ERE-G180

Right now, my fronts and sub are powered by the JL amp, rears off h/u power. However, because I added that little EQ, I'm running a single set of RCAs to the EQ, then running RCAs out from that to the amp. I'm using the built in sub x-over and control on the EQ, but have turned BBE or whaver off. Gains on my amp are set pretty low, as I was getting some hissing (which may have been the result of a bad installation, much to MIAPLAYA's dismay), and I have them crossed-over on the amp as well (around 70 for HP and LP)...

Is there any way to tune the amp without using a volt meter? Any advice people can give me with regards to the EQ? Shoudl I just ditch it for a better one?

Thanks guys!

Hissing might be b/c of "too many links" in the chain. Try to see if you still get it w/o the EQ.

Also, as a reference point, I like to do the whatever processing (x-overs, etc.) in the final stage, meaning the amp. So, I would set the EQ to through (no x-over) and use JL's HP/LP only.

As fo setting gains w/o a MM. Yes, use your ear. Set the HU volume at ¾ (27 to 28, I am guessing your Alpine goes up to 35). Have everything on flat (no bass bost etc). Put a CD that you know has good quality and relatively loud (many recordings are as low as -3db). Set the gains all the way down. Listen to the CD, raise the gains till YOU START hearing distortion, then, turn them slightly down. You want to get the max output at volume 27 w/o distortion.

Thanks, I'll try that tonight!!!

1. Defeat EQ
2. Gains down
3. Volume to 27

Question: The H/U has some sort of cross-over as well, and it has to be set somewhere. I'm thinking this is more of a bass emphasis sort of setting, rather than a cross-over. I don't have the manual with me to check what it is, though. Any idea on what to set that thing to?

question
Everyone always says the defeat the EQ when you set the gains by ear....why?
You should have the EQ set how you listen to your music, then play a sine wave of the frequency that you have boosted the most (if 80Hz is +3 and 5kHz is +2 and the rest is below, then play an 80Hz test tone to set the gain). This way you really are getting the most out of your setup. If you set it to flat, set your gains perfectly, then go back to how you have it tuned normally, you just threw off all of your clipping points. Now your headunit might clip at your most boosted frequency at 20 instead of 24. You think it's safe to turn it up to 24 if you set it on flat, but in reality once you hit 24 you're clipping at every frequency that's boosted in your EQ and you don't even know it.

Just something that's never made sense to me

Good point... Do you know where I can get some wav files to burn to a cd to test? (with these sine wave frequencies and what not)

This fine tuning is all new to me, so further input or clarification would be greatly appreciated guys! Thanks for educating this poor ig'nant soul.

Originally posted by tbuh
Thanks, I'll try that tonight!!!

1. Defeat EQ
2. Gains down
3. Volume to 27

Question: The H/U has some sort of cross-over as well, and it has to be set somewhere. I'm thinking this is more of a bass emphasis sort of setting, rather than a cross-over. I don't have the manual with me to check what it is, though. Any idea on what to set that thing to?

The HU's x-over CAN be set to flat too. What do you need to set up? Fronts, sub, or both? I can make some 0db tones and send them to you.

question
Everyone always says the defeat the EQ when you set the gains by ear....why?
You should have the EQ set how you listen to your music, then play a sine wave of the frequency that you have boosted the most (if 80Hz is +3 and 5kHz is +2 and the rest is below, then play an 80Hz test tone to set the gain). This way you really are getting the most out of your setup. If you set it to flat, set your gains perfectly, then go back to how you have it tuned normally, you just threw off all of your clipping points. Now your headunit might clip at your most boosted frequency at 20 instead of 24. You think it's safe to turn it up to 24 if you set it on flat, but in reality once you hit 24 you're clipping at every frequency that's boosted in your EQ and you don't even know it.

Just something that's never made sense to me

It is a fact (and from my experience at least) that most recordings out there are not nearly close to 0db, most are in the -2db to -3db range. So when you use a 0db tone (HAS TO BE 0db, make sure it is) you have your *** covered in any case, Also, slight clipping is "acceptable" and not detectable at all and well tolarated by speakers. Many people choose to have different ratios of clipping. Even JL's manual suggests to set everything at 3/4 of volume so at full volume (if you want so) you get slight clipping.

I'm setting up both fronts and subs. I'd really appreciate it if you could shoot me some files to burn on a cd tonight!

Use the 1000Hz for the fronts, and the 50Hz for the sub. BUT.... DO NOT USE THEM TO SET THE GAINS if you are not using the MM method... 1000Hz and 50 Hz at 27 volume migh blow your speakers, plus, if doing it by ear, it would be difficult to detect clipping, especially w/ the 1000Hz.

Use a good music CD as I said above. D/L the tones and just use them as refference or later on if you do the MM method.

Right click, save as:

http://members.cox.net/debyk/1000Hz.wav

http://members.cox.net/debyk/50Hz.wav

Originally posted by evangelos K
Use the 1000Hz for the fronts, and the 50Hz for the sub. BUT.... DO NOT USE THEM TO SET THE GAINS if you are not using the MM method... 1000Hz and 50 Hz at 27 volume migh blow your speakers, plus, if doing it by ear, it would be difficult to detect clipping, especially w/ the 1000Hz.

one thing you can do, is take your front speakers, wire them in series, and then put that on 1 channel of your amp for setting the gains. This will send each speaker 1/4 of the power of each channel on that amp and blowing them shouldn't be a problem even if you do drive the amp into clipping. For the sub amp you can do something similar, if you have a bridged amp then you can just use one channel, or you can borrow a friend's sub and do the same thing as with the front speakers.

Originally posted by 2001 SE #2
one thing you can do, is take your front speakers, wire them in series, and then put that on 1 channel of your amp for setting the gains. This will send each speaker ¼ of the power of each channel on that amp and blowing them shouldn't be a problem even if you do drive the amp into clipping. For the sub amp you can do something similar, if you have a bridged amp then you can just use one channel, or you can borrow a friend's sub and do the same thing as with the front speakers.

I dont understand how is he going to set the gains correctly this way??? The amp w/ an 8Ohm load will output ~38W on one channel. (speculation since it is a JL, same Watts from 1-4 Ohms, then I guess half at 8 Ohms). To get an good volume he will need to set the gains high, and when he connects the speakers back the way they are supposed to, the amp will make its rated 75W/channel... ?

Originally posted by evangelos K
I dont understand how is he going to set the gains correctly this way??? The amp w/ an 8Ohm load will output ~38W on one channel. (speculation since it is a JL, same Watts from 1-4 Ohms, then I guess half at 8 Ohms). To get an good volume he will need to set the gains high, and when he connects the speakers back the way they are supposed to, the amp will make its rated 75W/channel... ?

Exactly, to get a good volume he will have to drive the amp into clipping. The thing is, you aren't trying to get a good volume, you're trying to listen for this clipping. The amp will always clip at the same point, no matter what is attached to the output. If you attach something with a high impedence then when the amp starts clipping you might only be getting 20 watts at the speaker. This isn't nearly enough to blow the speaker, even if the amp is clipping, but it is certainly enough to hear the clipping. You set your gain just under the clipping point, then you wire your speakers back normally and then you're getting the max, unclipped singal from the amp.

*zoom!*

(right over my head)