2V vs. 5V Head unit?

[mlstrass 5,000+ posts]

Here's my experience with different pre-out voltages.

Have an Excelon with 4.5v and was running a sealed Tempest that sounded very good and hit pretty hard.

Move the sub/amp into the GF's car with a 2v Pioneer HU. Reset the gains correctly with a DMM and the sub sounded like crap!!! Just hollow and empty with NO impact. Tried turning up the gain and no difference. Messed with the EQ settings for hours on end and it still sounded like crap. Gave up for a few weeks.

Then I decided to try the "forbidden" and used the loudness button on setting 2 and the sub came to life. Also made her coax's sound MUCH better. What exactly does the loudness button boost?

Any ideas on why her HU made the sub sound so bad/have such little output? The only real difference was the pre-out voltage...//content.invisioncic.com/y282845/emoticons/banghead.gif.8606515f668c74f6de0281deb475b6fd.gif

 

[T3mpest 10+ year member]

Some HU's have built in processing. Perhaps your older hu had a built in bass boost, without even hitting a button? Again, a lower preout won't make a difference. Assumng you set your gains properly, the amp was still putting out it's RMS, it was just doing it with a lower input voltage. However, Xwatts=xwatts, regardless. Your DMM settings confirmed this. It doesn't matter what signal comes out of the hu, only what singal the amp is receiving, which in this case was still the same voltage as you had before. Loudness usually boosts the bass region and the top end, basically your tweets and sub's frequency range is boosted.

 

[squeak9798 5,000+ posts]

. The only real difference was the pre-out voltage...//content.invisioncic.com/y282845/emoticons/banghead.gif.8606515f668c74f6de0281deb475b6fd.gif

//content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif

Move the sub/amp into the GF's car

//content.invisioncic.com/y282845/emoticons/idea.gif.5acb6a39a9b92425414c316dda202bad.gif

That right there is a HUGE difference. You were comparing vehicle acoustics and setup differences; not preout voltage.

Not to mention....again, you compared completely different headunits. You compared MUCH, MUCH, MUCH, MUCH more than simply the preout voltages of the headunits. Different headunits, different features/settings/etc. You were not even anywhere close to comparing the preout voltages.

Also; With just about every Pioneer headunit I've used....for whatever reason they have always sounded better with the loudness engaged. Otherwise they have always sounded exactly how you described; hollow and lifeless.

 

[supa_c 5,000+ posts]

I have loudness on, it does make a difference.

 

[b0mbrman 10+ year member]

Ya this was cleared up in an earlier thread.
SQ differences between decks are likely due to quality differences between the units, not pre-amplifier output voltage.

Define quality

 

[luvinthebass 5,000+ posts]

loudness on my pioneer makes a huge difference, highs are more sharper and bass is more deep and dominant