What kind, and how much of a difference would i notice with 2v , 5v, or 8v preouts??

[AJ²06 5,000+ posts]

Bump for a goood question

 

[BlkonBlkFG 10+ year member]

It seems that when you have a higher preout voltage that you usually can turn the HU all the way up without it clipping...hence getting more out of your speakers and amplifier. Right?

 

[mlstrass 5,000+ posts]

Here's my experience, take it for what it's worth.

Built a sealed Tempest running off a PG amp with 500 watts. Sounded very good in my car. Excelon HU with 4.5v pre-outs.

Put it in the GF's car and the bass was GONE. Pioneer HU with 2v pre-outs. Turned the gain up all the way, still not much bass. Also noticed the Polk coax's didn't sound very good and they're amped.

Long story short, her HU has 3 levels of loudness and I had to use the MID one to get back the missing bass and make the speakers sound full and loud.

There seems to be more to it than "just match the amp gain to the pre-out", at least in this case there was as everything sounded like crap compared to running off of my HU.

 

[iceteebone 5,000+ posts]

It seems that when you have a higher preout voltage that you usually can turn the HU all the way up without it clipping...hence getting more out of your speakers and amplifier. Right?

gains are made adjustable so they can match the input voltage of your headunit. all source units will have different output voltages, meaning you have to adjust the input voltage, to match the output voltage of the source unit

Here's my experience, take it for what it's worth.
Built a sealed Tempest running off a PG amp with 500 watts. Sounded very good in my car. Excelon HU with 4.5v pre-outs.

Put it in the GF's car and the bass was GONE. Pioneer HU with 2v pre-outs. Turned the gain up all the way, still not much bass. Also noticed the Polk coax's didn't sound very good and they're amped.

Long story short, her HU has 3 levels of loudness and I had to use the MID one to get back the missing bass and make the speakers sound full and loud.

There seems to be more to it than "just match the amp gain to the pre-out", at least in this case there was as everything sounded like crap compared to running off of my HU.

apples and oranges. too many variables //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif remember the scientific method

 

[yacob.naif 10+ year member]

only difference you will see is a decreased chance of seeing any ****** in the next few months, cause you spend all your money on a headunit to have 3 extra volts of preamp line-voltage.

 

[BlkonBlkFG 10+ year member]

No matter how much I spend on whatever I buy, I will always see plenty of ****** //content.invisioncic.com/y282845/emoticons/yumyum.gif.0556df42231b304b9c995aefd13928a8.gif . Anyways, I'm trying to decide if its worth it or not. Is a couple extra volts or different HU gonna make everythingsound better then it allready does, or is there gonna basically be no difference?

 

[xploit2 10+ year member]

I doubt that there is No difference. the difference in SOUND is very noticeable going from 2V to 5V.

 

[Rochambeau 10+ year member]

******... Is that a new Blaupunkt HU? //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[dgr00s 10+ year member]

going from 2 to 5 the sound difference was very impressive to me, going from 5 to 8 wasnt as noticeable.

 

[BlkonBlkFG 10+ year member]

exactly what I thought...see, the truth comes out. So we've come up with 2v to 5v is a huge difference and 5v to 8v isnt very much of a difference. So its sounds like it would be a good idea to maybe get a HU with atleast a 5v preout.

Any others??

 

[yacob.naif 10+ year member]

The reason i have a hard time believing it's that noticeable of a difference is because that's the absolute PEAK output.

The pre-amplifier output voltage isn't even rated as RMS or MAX, so it's most likely MAX

It also doesn't specify if that BEFORE the output actually clips, or at full tilt.

AND most head units don't even tell you what resistance those numbers are presented at.

So if one brand rates their outputs at MAXIMUM output, at completely clipped FULL TILT, and another brand rates theirs RMS, with the HU volume at a reasonable, unclipped level, then they'll be two completely different numbers, and there's NO provisions for explaining the conditions for the measurement in the specifications, so you REALLY don't know WHAT you're looking at. They may as well be 2 completely imaginary numbers that someone made up.

 

[BlkonBlkFG 10+ year member]

Thats true....Alpine states on their website that their preouts go up to 2v, and then anything after that it will start clipping. So how do you know once you've reached your 2v limit??? How do you find that out?

 

[xploit2 10+ year member]

Thats true....Alpine states on their website that their preouts go up to 2v, and then anything after that it will start clipping. So how do you know once you've reached your 2v limit??? How do you find that out?

read the HOW TO SET THE GAIN sticky in the amplifier section. u will find your answer there

 

[BlkonBlkFG 10+ year member]

Oh ok...allready done then. SQRT(RMS of amp x load)....then turn everything flat and turn your volume to 80% of the maximum. Play a 0db 1khz tone and adjust your gain until you get the voltage you calculated. Right??

 

[xploit2 10+ year member]

Oh ok...allready done then. SQRT(RMS of amp x load)....then turn everything flat and turn your volume to 80% of the maximum. Play a 0db 1khz tone and adjust your gain until you get the voltage you calculated. Right??

yes sir!.. thats you answer. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif