Question about Pre-Out voltage...

[endofdays89 5,000+ posts]

speakers don't necessarily sound better using a higher pre out voltage.

 

[microhaxo 10+ year member]

To rephrase what i was saying above:

For whatever reason achieving 45v using 6 out of -10 to 10 on low and 4 out of -5 to 5 on the sub level produces more bass than turning up the volume from 19 to 24 and having the low to 0 and the sub level to 1.

They both produce 45v but the first option produces much more bass.

I would be able to turn the gain down on the amp and set the low to 6 and the sub level to 0 and have it on 45 v on volume 24 but the problem with that is: my vocals are EXTRA loud and it would only sound good if i was driving 60mph with my heat going. Otherwise it sounds way overkill.

Any ideas?

Here is Video of volume 19 setup:



Hits good //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[msimon 10+ year member]

To rephrase what i was saying above:
For whatever reason achieving 45v using 6 out of -10 to 10 on low and 4 out of -5 to 5 on the sub level produces more bass than turning up the volume from 19 to 24 and having the low to 0 and the sub level to 1.

They both produce 45v but the first option produces much more bass.

I would be able to turn the gain down on the amp and set the low to 6 and the sub level to 0 and have it on 45 v on volume 24 but the problem with that is: my vocals are EXTRA loud and it would only sound good if i was driving 60mph with my heat going. Otherwise it sounds way overkill.

Any ideas?

Here is Video of volume 19 setup:

Are your "vocal" speakers on an amplifier?

 

[microhaxo 10+ year member]

No they are not. They are getting 17w rms each via deck.

 

[MmatsDude 10+ year member]

speakers don't necessarily sound better using a higher pre out voltage.

They did to me, sounded much much better sq wise.

Or it must of be cuz my eq has a crossover and the 10 volt line driver built in.//content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif

 

[msimon 10+ year member]

No they are not. They are getting 17w rms each via deck.

You might already know this, but when you increase the "low" setting on your head unit you are actually using the equalizer to boost low frequencies centered around 60 hz for both the sub and the speakers.

If I were you, I would set your equalizer flat, this means set your "low", "mid", and "high" settings to 0 db. I would set the LPF on the head unit to 78 hz, and set the amplifier LPF to pass. Then set your gain and adjust the sub level on your head unit to get the desired head unit output. Don't worry about voltage, just adjust the gain and sub level until you get the desired output. Of course if things sound bad, back off the gain or the sub level.

 

[microhaxo 10+ year member]

Shouldn't i worry about the voltage though? I don't want to end up sending a clipped signal to the sub.

Also this would mean that i would have to go to volume level 24 again. at volume 24 i am able to not use ANY low and sub level is set at about 1 out of 5, but it seems that every notch on the sub level is about 1.7v increase on the amp. So i think the lowest volume i could go with 0 low is 22.

Could you explain this "boost" around 60hz, am i unable to see any voltage increase from this?

When i use 0 low and obtain 45v on the amp the output is much lower than when i obtain 45v with low setting of 6.

 

[msimon 10+ year member]

Shouldn't i worry about the voltage though? I don't want to end up sending a clipped signal to the sub.

Most music is recorded at -6 db and it is dynamic. The only way that you can even reach full power is if you are playing a 0db sine wave. I forgot to mention, when using the method described above use music, not test tones.

 

[microhaxo 10+ year member]

That song in my video: put on by young jeezy and kanye west puts out 45v = 506w with my settings exactly on the note Recorded for about 4 second.

I forgot to say that i use a -3db 50hz tone to setup the amp not a 0db.

 

[msimon 10+ year member]

That song in my video: put on by young jeezy and kanye west puts out 45v = 506w with my settings exactly on the note Recorded for about 4 second.

I forgot to say that i use a -3db 50hz tone to setup the amp not a 0db.

Just set it up so that it sounds good to you. If you can't get it to sound good enough, then change the install or the equipment...

 

[microhaxo 10+ year member]

Wow, i just turned off the LPF on my amp and used the one on the deck and what i used to get 45v now gives me 65v with no settings changed at ALL! So i set it up and now i can make the Low to 0 and i have the sub level on the deck to 5 full and volume at 20 (previous settings were Low 6 sub level 4 and volume 19 with lpf on amp on.) and it is VERY VERY CLEAN but very VERY strong! having clean bass is way better than boosted bass.. Thank you very much msimon. I am still within my 45v limits but now im way better!

Apparently using LPF on the amp uses up some power?

 

[msimon 10+ year member]

Wow, i just turned off the LPF on my amp and used the one on the deck and what i used to get 45v now gives me 65v with no settings changed at ALL! So i set it up and now i can make the Low to 0 and i have the sub level on the deck to 5 full and volume at 20 (previous settings were Low 6 sub level 4 and volume 19 with lpf on amp on.) and it is VERY VERY CLEAN but very VERY strong! having clean bass is way better than boosted bass.. Thank you very much msimon. I am still within my 45v limits but now im way better!
Apparently using LPF on the amp uses up some power?

My only guess on the LPF using power is that you could have had the LPF set a rather low frequency where there actually was some attenuation at 50 hz.

I'm glad to hear everything worked out.

 

[Horsemanwill 10+ year member]

just curious did i miss what amp it was?

 

[eharri3 10+ year member]

Ive been through two Alpine head units, a 2 volt 9883 and a 4 volt 9886. I run an Alpine MRP-M500 and an Eclipse EA4200.

With the first head when tuning the sub amp using a DMM the voltage wasn't right until the gain was set at just under .5 volts. The Eclipse gain dial ended up centered precisely at the 2 volt mark without me even looking at it. With the second unit the sub amp wasn't right until the gain was just over .5 volts but before 1.9, the half way mark. The Eclipse ocne again sounds perfect at or near the notch that matches the HU's output voltage.

After doing some research Ive found some Alpines have weaker sub pre outs and probably with most mid or lower level head units they may not consistently put rated voltage or put out the same on the sub pre outs as they do on the front and rears. Goes to show, you can't really set gains based on that.

Other than that I'm not really worried about it. The sub sounds perfect and I don't see how getting more voltage at the head unit or some form of line driver would do anything for me if it doesn't change the loudness or performance of the sub. Sounds to me like you're whole setup is jacked up and you're not giving yourself all the volume you need to get full voltage on your sub outputs anyway because you're limiting your volume to compensate for a weak front stage.