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Alpine 7998!

[quote="Darthness"]i'm guessing that a head unit with higher-voltage preouts would allow me to keep the gain lower? [/quote]
The gain setting is a setting.
It corresponds to your HU voltage, that's what it's designed for - so you can tell your amp "expect a signal this large", and so it performs as designed.

The best gain setting is the CORRECT gain setting - not higher, not lower. ;)

Tell me this - what's the benefit of a lower gain setting?
Sure, there's a ton of people out there clipping the hell out of their audio signal, because they have their gain knobs cranked way beyond the signal they are sending their amps - set incorrectly - and sure, those people could benefit from turning their gains down...
...but let's not start a new myth, like "lower gain = better". ;)

We've got ENOUGH myths already in the car audio world! :scorp:

[quote="Justin from Detroit"]noone claimed that is what fixed it....[/quote]
No, I thought you were basically just saying you thought the HU was a POS. ;)

Darthness said he was having the same problem as you - and that was why he was justifying mandating such a high RCA voltage level for his new HU - the 2+2=4 being that he believes that would solve some noise problem that he's having. :help:

I believe what he really wants is:
1) a head unit that meets the list of ergonomic/feature requirements he listed
2) his noise problem to go away

I also believe that for some reason he's linking the two - which can surely lead to heartache after the dollars have been spent and it's discovered that the noise problem still exists - and maybe even has changed! :surprised

I'd bet you've been in a similar situation. Everyone has at some point.
It's not worth it anymore to try to help people build a bridge to avoid falling in the potholes, you know? :p

indeed. sorry if i don't always come across clear enough... what i meant by that was that in order to get the right voltage i have to have the voltage jacked.. i'm guessing that a head unit with higher-voltage preouts would allow me to keep the gain lower? and im 85% sure that the noise in my system (That i hate!) is coming form my ground wire. i'm going to address that tommorow. the deck i use right now is noisy in that i can hear the cd spinning and such when i change the song but its not like the ground noise im getting.

[quote="geolemon"]
Justin's problem has to do with noise...
...and noise isn't "fixed" by a higher voltage level. ]

noone claimed that is what fixed it....

[quote="Darthness"]it was a 0dB test tone.... and i did NOT use JL's . there was a formula in another thread that i used. Also, my amp accepts from .2v to 9v.

btw, that first sentence was supposed to be "justin has" sorry....

and i'd appreciate it if you did not talk to mnumberse like i'm dumb. thanks :) [/quote]Well, that's some key information! :p

Justin's problem has to do with noise...
...and noise isn't "fixed" by a higher voltage level. ;)

Noise is entering the signal path somehow - the only way to eliminate it is to eliminate the source of the noise.

Running a higher voltage level will only mask the noise to some degree - but ONLY if the noise is entering the signal path as induced noise into your RCA cables. If the HU itself is noisy (as he seems to have identified), the voltage level of the outputs is irrelevant. It makes no difference if you've got 1v outputs that have 10% worth of noise on them, or 8v outputs that have 10% worth of noise on them - in the end, you still have 10% noise.

The ONLY benefit to higher voltage levels on your RCA cables, is for noise that is induced into the RCA cables - and it's not a fix, it's a duct-tape band-aid. ;) Make sense?

Your amp accepts input voltage as low as 0.2v, so 6v is hardly a requirement.

Why narrow your list of potentially suitable head units? :thumbsup

That's why I regurgitated your other list of "what I want in my HU" back at you - based on what you yourself said (you made that list), that's what you want to shop for. :cool:

it was a 0dB test tone.... and i did NOT use JL's . there was a formula in another thread that i used. Also, my amp accepts from .2v to 9v.

btw, that first sentence was supposed to be "justin has" sorry....

and i'd appreciate it if you did not talk to me like i'm dumb. thanks :)

edited: wtf.

[quote="Darthness"]why i want higher voltage - right now i'm having the same issue just has, i belive, i'm not entirely sure how much HU voltage affects this but my gain is currently set to about 3/4 of the way up. calculated 37.4v and tuned it while playing a 50Hz test tone with a DMM[/quote]
Take a deep breath, put the coffee down.
Have another go at it.

I'm not sure what issue "just has" is - the sentence doesn't make sense.

I also don't know why you would use JL's "measure it with a voltmeter" technique for setting your gain control unless you have a JL amp (they know their voltages ](did you use a test tone recorded at a -0dB level? That's absolutely critical to know, and difficult to find :surprised )[/i], but more fundamentally is a pretty rube-goldberg way of addressing something related to sound...

It sounds to me like there's a fundamental misunderstanding of what the gain knob does on your part. ;)

Think of the gain knob as a doorway, with an adjustable top threshhold.
If a tall person was going to walk into the doorway, you could turn the gain knob in one direction, and effectively raise the top of the door so that the tall person didn't lop their head off as they walked through.
[i](that's literally what happens when you "clip" an amplifier - the gain is set improperly for the size of the signal going in - and you "lop" the part of the signal off that won't "fit through the door". :sad017: )[/i]
And if a short person was going to walk through the doorway, you could lower the threshhold of the door to their height, custom-tailoring the doorway to them.
[i](You ideally size the threshold to your signal, so that the amplifier knows what size signal to apply to it's standard - as in "not going to change no matter what your gain knob is set to" ;) - output voltage - ie, power.)

The key is this:
Every amplifier on the market is built to accept a range of voltages, as low as 0.5 or even 0.25 in most cases, up to 5v, 6v, or even higher.
You want a voltage level that'll land IN that range, not outside of it, or you'll have another fundamental incompatibility. ;)

Where the gain knob ends up adjusted to simply depends on the voltage level you are sending it - high isn't necessarily bad, if that's appropriate. Low isn't necessarily bad, if that's appropriate. Otherwise, it wouldn't be an [b]adjustment.[/b] :p

So my point is...
[quote]
to answer your questions...
-knob
-rotary is nice.
-ergonomics
-simple
-simple& readable
-i'd rather it match the dash, yes
-i'd like a healthy mix.
-i like to make mp3 discs with a bunch of songs, so im going to say mp3.[/quote]
...take THIS list of features, and go shopping (I'd suggest adding the crossover and multiple pre-outs to the list ;) ), and don't get hung up on RCA voltage. All HU these days have very high voltage - I haven't seen a HU under 2v even recently!

why i want higher voltage - right now i'm having the same issue just has, i belive, i'm not entirely sure how much HU voltage affects this but my gain is currently set to about 3/4 of the way up. calculated 37.4v and tuned it while playing a 50Hz test tone with a DMM

to answer your questions...
-knob
-rotary is nice.
-ergonomics
-simple
-simple& readable
-i'd rather it match the dash, yes
-i'd like a healthy mix.
-i like to make mp3 discs with a bunch of songs, so im going to say mp3.

[quote="Darthness"]so could anyone throw some units at me? looking for something with 6v or better pre-outs, cd player, removable face, and any other features that you think i should need :P[/quote]
Why 6v pre-outs? Do you have a noise floor issue? If not, they don't benefit you at all. My old Sony Mobile ES deck (a favorite of IASCA competitors of a few years back) had about 0.5v pre-outs, and it lived in the winners circle plenty - in competition where noise floor is actually [i]measured[/i] on the score sheet. ]One thing that I would suggest:[/i]
[b]Built in crossovers.[/b]
These are always defeatable, so they aren't any harm if you don't have a use for them - but when it's time to add a sub amp - bang! Plug it into the sub outputs, and you can not only control the sub Xover settings from the HU, but you also get a "sub level" control, so you don't need to run a remote gain knob right from the amp - it's built into the HU.

...then, when it's time to add an amp to your front stage... you can again set the crossover right from the HU - and be assured that it's working as a true "crossover" (meaning the crossover points truly match and compliment each other - something you can't accomplish with two discrete amps with separate onboard filters ;) ).

Typically, you can get into a HU that plays CD's as well as MP3's, with at least front/rear/sub RCA outputs, detachable face, and a more advanced level of features including onboard crossover and DSP, for around or under $200 even in a retail shop. :cool:

As far as what "features" you should be looking for...
Are you an up/down buttons, or rotary knob type of person?
Are you more interested in ergonomics, or features?
Are you interested in simple controls, or complex ones?
Do you want a simple, readable display? Or a big, flashy graphic/animated one?
Do you want a look that matches your dashboard, or want your HU to "stand out"?
Are you more interested in reliability, or performance?
Would you rather have a HU with an advanced CD transport, or one that can play MP3's?

There's a lot that can differentiate one HU from another - but a TON of it is personal preference that we can't really guide you on, unfortunately.