Scrap the headunit - just run an amp?

In Car Entertainment - NO SELLING OF I.C.E. PLEASE

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cee
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Fri Jan 21, 2011 11:00 am

So I've been thinking for a while - what really is the point in a head unit? I only ever listen to music from my mp3 player so why not plug it directly into the amp and don't bother spending the money on a head unit?


The only potential issues I can think of are this:

- Need a switch for the amp
- Maybe loss of some EQ control? (Only if I get a rubbish amp though surely?)
- Powering of the amp may be dodgy??


A few points to add:

- I only intend to run 4-6 speakers with sub (I see a sub as pointless)
- I was tempted to get an Android tablet PC (touch screen) to plug in as a kind of portable car PC / mp3 player kind of thing - this would plug into an amp in the same way as my iPod
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Ziggy
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Fri Jan 21, 2011 11:17 am

Powering the amp wouldn't be a problem, as that's totally separate from the headunit anyway.

What voltage does a 'standard' headunit remote wire use to switch an amp on? If it's 12v (or if the amp can handle 12v being used anyway), just wire an ignition switched live to the remote connection on the amp. No need for a switch, although you could easily put one in that wire if you didn't want it to always be on.

EQ control would be a concern - you'd need to be sure that whatever source you were using had enough control over its output.

Extremely easy to try all of the above out - & if you end up wanting a headunit too, you've not lost anything.

Do you just leave your mp3 player on random? Even then, I wouldn't want to be using the controls on mine as the only way of adjusting the volume while driving...
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cee
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Fri Jan 21, 2011 11:21 am

Ziggy wrote:Powering the amp wouldn't be a problem, as that's totally separate from the headunit anyway.

What voltage does a 'standard' headunit remote wire use to switch an amp on? If it's 12v (or if the amp can handle 12v being used anyway), just wire an ignition switched live to the remote connection on the amp. No need for a switch, although you could easily put one in that wire if you didn't want it to always be on.

EQ control would be a concern - you'd need to be sure that whatever source you were using had enough control over its output.

Extremely easy to try all of the above out - & if you end up wanting a headunit too, you've not lost anything.

Do you just leave your mp3 player on random? Even then, I wouldn't want to be using the controls on mine as the only way of adjusting the volume while driving...
Pretty much - or occasionally hit next track. Volume would be a slight issue but as I use my iPod through an AUX input with my head unit I tend to control it using the ipod rather than the HU anyway... Although I do see your point here.

As for EQ settings I was mostly talking about speaker balance etc. - as I've never owned a car amp I'm not sure what control they actually have built in.
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Ziggy
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Fri Jan 21, 2011 11:40 am

I've never had an amp with a balance control on it - they tend to have high/low pass filters & an input level control but not much else.
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tari
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Sat Jan 22, 2011 6:43 pm

Why not just get a Graphics Equaliser? I used to have an alpine (single din) one years ago, and that done the job very nicely sound quality wise..
You can just plug your MP3/Ipod straight into it an use the volume on the EQ!
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rob0r
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Mon Jan 24, 2011 1:27 pm

I've run my iPod through amps multiple times over the years. As above, wire it up as normal and then run an ignition live to the remote. The sound quality is good enough for me just through the iPod but I'm not an audiophile :mad:, a sound equaliser is a good idea though!
cee
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Mon Jan 24, 2011 3:00 pm

What exactly is a sound equaliser? Is it just a box which allows you to fiddle with EQ?
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schnaarf
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Mon Jan 24, 2011 3:46 pm

cee wrote:What exactly is a sound equaliser? Is it just a box which allows you to fiddle with EQ?
yep, EQ stands for equaliser
cee
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Mon Jan 24, 2011 4:37 pm

Ha of course it does (blonde...)

If I was to fit a graphic eq I may as well just had a HU then, basically :mad:
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tari
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Mon Jan 24, 2011 7:50 pm

cee wrote:Ha of course it does (blonde...)

If I was to fit a graphic eq I may as well just had a HU then, basically :mad:
erm... Good point!

How about a line driver! Not as good as a graphics equaliser, but still let's you tweek the sound. And it would wire up the same as your amp!
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cee
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Mon Jan 24, 2011 7:55 pm

yeah I was thinking maybe a basic hifi preamp (you can get mini ones) that could run off 12v that I could keep in the boot with the amp...

Then again if I'm spending the dollar on a preamp/equaliser I may as well get a HU, or even keep my crappy HU (which I was pleased to find has RCA outputs)


Hmmm
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tari
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Mon Jan 24, 2011 8:25 pm

A line driver would make a good difference, as it would increase the voltage of your RCA outputs to between 4 and 6 volts!
It makes a difference with the quality of sound, even from a standard headunit.
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