headunit pre amp voltage

I wanted to know how exactly the headunits pre amp output voltage actually works. I have a Panasonic headunit that has 3 pairs or RCA's rated at 5 volts. Now really the only one I am going to question is the subwoofer one. My headunit also has an adjustment on it for the subwoofer where I can adjust it from -6Db's to +6Db's. I just wanted to know how those settings and the 5 volts work with eachother, meaning when do I have the actually 5 volts output?

Preamp voltage is generally rated at the max output the preamp is capable of.  So, for your HU to output 5 volts, the volume and sub output levels would be maxed while playing back a signal in the passband at 0db ref level.

-------------
Support the12volt.com

huh? lol. I totally did not understand that. Well, I have my headunit volume at a 30 out of 40. i have my headunit sub output set to +6Db's and I have the amps gain at 1/2.  If any of this even matters?

Like I keep saying, you have a LOT to learn.  Do some research and figure out my post.  When you understand it you may be ready to come give advice to others here.  Seriously.

-------------
Support the12volt.com

What does me giving advice have to do with this topic?

Sorry but the advice I give on here is from what I have learned through trial and error and through professonal installation shops. I have never had a complant from anyone about a system I had installed in their vehicle. Yea I know I dont know everything there is about this stuff, but not a single person on here can say they do.

This forum is for professional installers to share their expertise and to give advice to the general public.  When I see incorrect information posted or posts like yours where you do not understand basic concepts, then you are demonstrating that you do not have any real "experience" that can help other people set up and use their systems.  You have maybe played around with car audio for a long time, but you are not an installer if you do not understand things like setting gains and how preamps work.  You not understanding this topic means you are not qualified to give advice on this forum.

-------------
Support the12volt.com

audioman2007 wrote:

---

huh? lol. I totally did not understand that. Well, I have my headunit volume at a 30 out of 40. i have my headunit sub output set to +6Db's and I have the amps gain at 1/2.  If any of this even matters?

---

In terms of your question - no, none of that matters.

The idea is drive your ampliier as hard as you can without overdriving and clipping it - so the precise mixture of gain/volume/boost is really up to you.

I think the *best* way to do it is to keep the gain knob as low as possible without using much or any bass boost (in your case, I'd probably set gain with the boost @ +1 or +2db for the first round of tuning - certainly not any higher under any forseeable circumstances) - but to be honest I'm always jerking around this combination in my own car b/c I can't ever decide what sounds best. 

Adding the bass boost centers the boost around a frequency -so your response gets peakier - so this isn't really the best way to add volume - and most audiophiles around here will tell you to leave it flat while adjusting volume and gain instead - +/-0db is probably where you boost will end up.

Managing the volume knob, the gain, the subwoofer volume, AND the bass-boost to get the best response while maximizing output can really be quite a challenge.

Remember - your maximum output should ONLY be determined by DMM and precise voltage measurement.

https://www.subwoofertools.com/forum/setgain.asp

https://www.subwoofertools.com/default.asp?Contentid=19&CategoryID=18

https://mobile.jlaudio.com/support_pages.php?page_id=143

-------------
"I'm finished!" - Daniel Plainview

First off, You dont have to be a car audio installer in order to give advice. I am not a contractor, but I have already built houses. Does that mean I cant give advice in a forum for building houses? I think not. The point I am trying to get at is that there are tons of others on here that try to give advice, but are wrong. I see this but dont go and flame them for being wrong and asking them to leave this forum. I go and fix or further explane it to help everyone out. I remember you Dyohn helping me in a rescent topic where you helped me re-set my gains. I took your input and used it to change not only my system, but also alot of other people that I know throughout my work place and people I just know. And now I take that info and use it to help others out. I dont do what "some" on here do and totally attack those that are incorrect. Im sorry if I dont know EVERYTHING there is to know about car audio, but there is also now a single person on here that knows everything about it. Oh, and I highly doubt you knew tons about car audio when you first became interested in it. And I am sorry for attacking you in this post, but I am very offended that after I post 2 "incorrect" posts, that I have you jumping all over me. And I dont get this just from you. I had post in another topic explaning in more detail how a certain "thing" works only to get flamed by another member, only to later get told by yet another member that I was INDEED correct. All I am asking for is alittle respect in here like everyone deserves. If  am not correct in a post, I dont mind you telling me so and fixing it (that would help me out also), but dont have to be nasty about it and make me look bad. Thank you.

The difference is when I was "starting out" (probably before you were born) I did not try to act like an expert and tell other people how to do things.  You have repeatedly demonstrated a basic ignorance about car audio that makes it scary to me when you try to act like an expert.  I've been working in and around this field (including for several manufacturers) for more than 35 years, so about now I think I can spot someone who knows what they are doing and tell the difference between them and a hobbyist who still has a whole lot to learn.  You have over 500 posts on this forum yet over and over again you prove that you really do not understand the basics of car audio technology.  Please stop trying to tell other people how to do things until you do understand.  Read and learn for a while.  Ask your questions.  Be humble.  Thanks.

-------------
Support the12volt.com