Adjusting db+- on head unit sends more voltage to amplifier???

[FadedSpy 10+ year member]

I'm not sure if this is common knowledge but when I got my subs and wired a digital voltmeter to the amp I had my db on my ken wood Exelon head unit set at +3 db and the voltage hung around 13v. When I adjusted my db level to +9 then my voltage hung around 13.8 and when I max it out at +15 db then the voltage meter reads 14.2

My question is...should I adjust my amp to play with my head unit all the up at +15 db's so I can keep my voltage as close to 14.4 as possible? Will it hurt anything as long as I'm not clipping the signal? At +15 I had to turn my gain way down to about 30% which should be better for the amp in theory?

I always though the db setting on the head unit was a type of bass boost and bass boost is bad! I have tried to google this information but can't seem to find anything on this topic so I'm coming here.

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[Spl4200]

Don't quote me on this but I beleave I've read that +15 sub option just puts you to +0 db. That's how I set my sub...

 

[garychoffmann 10+ year member]

Are you saying that your voltage at the amp power wire is increasing? Or the rca voltage?

 

[blazian87 10+ year member]

Don't quote me on this but I beleave I've read that +15 sub option just puts you to +0 db. That's how I set my sub...

Yes, this is true for most head units. OP, if you put it at +3 it's as if you're putting it at -12db.. Its not a bass boost. Make sure to keep Loudness off too as this is a bass boost. Keep it at +15 to get full potential of sub and keep your gains down.

It can also act like a bass knob for people who don't have a physical knob up front.

 

[FadedSpy 10+ year member]

This is great news! I have blown 2 amps already due to under powering them but I couldn't figure it out because I have a group 31 agm and the amp was only 2k rms so I was like wtf?! Then someone told me to turn the db on my head unit up to get proper voltage to the amp and as soon as I turned it all the way to to +15db now I'm at 14.2-14.3 and my stereo subs are kicking me in the kidneys way too hard, lol. I just wanted to make sure I'm not taxing my subs or amp too hard to cause either to blow, I'm running out of money for repairs and my wife's running out of patience as well, need to get it right. I was able to turn my amps gain down from 60% to about 30% after increasing the db on my head unit from +3 to +15 and it hits about the same

 

[los33 10+ year member]

The sub level which you are currently speaking of is not a bass boost.

On most headunits if not all that include this, have this feature so you can get the full pre-volts out of your rca connection.

If you put it at the lowest setting possible and play your headunit at 95% volume and monitor your rca with a dmm you will see

you get close to no voltage which could be .2-.5 voltage depending on the max voltage your pre outs are.

If you have a very weak amp then its best to keep it at max, if not set it so you get max watts rms without clipping with the amp near full gain then reset the amp gain back to minimum and set the gain on amp for the subs near no clip range.

 

[FadedSpy 10+ year member]

Are you saying that your voltage at the amp power wire is increasing? Or the rca voltage?

Yes, my voltage meter is wire directly to my amp -/+ and voltage now hangs at 14.2 ish

 

[FadedSpy 10+ year member]

The sub level which you are currently speaking of is not a bass boost.
On most headunits if not all that include this, have this feature so you can get the full pre-volts out of your rca connection.

If you put it at the lowest setting possible and play your headunit at 95% volume and monitor your rca with a dmm you will see

you get close to no voltage which could be .2-.5 voltage depending on the max voltage your pre outs are.

If you have a very weak amp then its best to keep it at max, if not set it so you get max watts rms without clipping with the amp near full gain then reset the amp gain back to minimum and set the gain on amp for the subs near no clip range.

I'm running an AB VFL 150.1

 

[FadedSpy 10+ year member]

I should add that my hu goes to -15db as well as +15db. Why would anybody want to turn it down to -15 ?

 

[Spl4200]

In my case, I use it for when my kids are in the car.

 

[garychoffmann 10+ year member]

Voltage to your amplifier does not increase with settings on your head unit. There is something else going on.

 

[Louisiana_CRX 5,000+ posts]

The amp may like higher voltage to work efficently

 

[FadedSpy 10+ year member]

The guy at my local car audio shop was the one who told me to turn my setting from +3 to +9 because he said I wasn't giving my amp enough voltage. I was running it at +11 and my volt meter reads 13.2-13.7 and at +15 it's 14.0-14.2

 

[garychoffmann 10+ year member]

The amp may like higher voltage to work efficently

Yes, very true but we are missing the whole story, idle, full tilt etc. But adjusting the head unit does not increase voltage. Especially by 1.2 volts.

 

[garychoffmann 10+ year member]

Is that full tilt? Moderate? He was talking about your rca voltage. Rca voltage can definately help. If your signal was too weak and the amplifier was trying to create max power with a weak input it could have been clipping a bit becoming very inneficient.