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View Full Version : Disadavatage of low volt pre-outs?



purerx7tt
03-29-2005, 06:53 PM
Ok looking into getting the new alpine cda-9853, according to alpines website they are only 2v pre-puts, compared to 8v that the eclipse has. I will be running two amps, one bxd1500 and the new 2 channel 400 watt diamond amp, which powers two 12" m6's, rainbow pro comps and and extra set of alpine type x tweets, than a full 15 band parametric eg dsl, pioneer eq-76000. ANyways so by having low prevolts does this affect or lower the quality of my system?

iceteebone
03-29-2005, 06:55 PM
preout voltage is overrated imo. all you are doing is matching the input voltage of the amp, to the output voltage of your headunit. the only real advantage of higher preouts is that you don't have to turn the gain as high therfore less chance of noise. if you get zero noise at 2 volts, going to 8 volts is gonna do nothing.

forbidden
03-30-2005, 05:03 PM
Unless the output resistance is lower and if it is rated across the entire frequency spectrum rather than at 1000hz where most companies measure their voltage at.

3.5Max6spd
03-31-2005, 07:59 AM
those eq's of yours have preamps of sorts

Nikuk
03-31-2005, 08:17 AM
Please keep in mind, not all amps like higher input voltages.

livingsacrifice
03-31-2005, 12:34 PM
Is it also true that some amps may not like anything higher than 4v?

Nikuk
03-31-2005, 12:37 PM
Is it also true that some amps may not like anything higher than 4v?


I dunno about that. I can say that some DEI (Viper, Orion, etc) do not like inputs over 5.0'ish. At least, not the ones that I have played with.

It ***** for me, too... as I'm running Orion amp's in my truck right now. ;)

Alpine2005
03-31-2005, 03:40 PM
iceteebone is right!!

the higher the voltage the less noise the RCA's will put up form other cable around them.

just keep the RCA cable far form any other power cable and keep them short as possible and also you can cover them with same split loom so you won't get any noise.

Nikuk
03-31-2005, 03:43 PM
hmmm.... my rca's cost $7, are 17' long, and ziptied to my 1/Ott power cable that pulls 80-190 amps...

Not a hint of noise. :wow:

Not that it would be too noticable at 190amp volumes. :)

Johnny Drama
03-31-2005, 03:44 PM
Nick can you elaborate on the Orion and Higher voltage for me, IHoP may be better so not to jack this thread

jujumantb
03-31-2005, 03:46 PM
Little known fact:
A lower voltage will inherently have LESS native distortion, but will obviously be more likely to pick up interference.

micah
03-31-2005, 04:06 PM
theres alot of amps that dont take very high voltage. when your reading specs just look for input sensitivity and it will give a range of whatever volts it will take.

theCybe
03-31-2005, 04:17 PM
I read something about Alpine headunits not putting out their full preamp voltage unless the "SUB" slider was set all the way up; Is this true of other headunits, like my Sony?

3.5Max6spd
03-31-2005, 04:31 PM
preout voltage is overrated imo. all you are doing is matching the input voltage of the amp, to the output voltage of your headunit. the only real advantage of higher preouts is that you don't have to turn the gain as high therfore less chance of noise. if you get zero noise at 2 volts, going to 8 volts is gonna do nothing.

I agree with you to a degree- keep in mind there are various types of noise- not something that you will hear as 'noise', rather elements that degrade the quality of the signal transfer- the hotter the signal from the source, the better results yielded.

forbidden
04-01-2005, 01:35 PM
theCybe, yes you have heard correct. Most cd player in the market today cannot make their full output under normal use conditions. This is due to multiple facts. First is how the voltage is applied across the frequency spectrum, most manufacturers rate and apply their votlage with a 1000hz test tone and not across the full spectrum. Next issue is the fact that their outputs clip when you get close to full volume, once this happens sure the voltage may be reading 6.5 volts or 4 volts or whatever, but the signal is square clipped all over the map. Read distorion out of speakers at this point. There are very few cd manufacturers that use non-clipping preouts and even fewer that also apply their output voltage across the frequency spectrum as compared to at 1000 hz. Eclipse just happens to be one of these companies.

Loudrango112
04-02-2005, 11:04 PM
I went from a 8 volt on my pioneer.... to 4 on my dvd player... and I have to almost turn the amps gain ALL the way up... compaired to only a quarter...