Taking the amp out of a head unit

bl3nd3r · 03-18-2008, 12:31 PM

I am working on putting my Car PC in and was looking at different options to amplify the sound. I was looking over at 41hz.com at the AMP9 but see that the price is similar to a few decent head-units I had bought in the past. Plus I would need to install all the components on the board of the AMP9.

My question is, would it be possible to take an old head-unit and remove the amplifier from it? It seems like the board with the components would be small enough and that it would be a very cheap alternative.

scott_fx · 03-18-2008, 02:06 PM

this was recently posted:
http://www.si5.com/products.php?pID=4038

probably a easier alternative

bl3nd3r · 03-22-2008, 09:25 PM

Quote: Originally Posted by scott_fx

this was recently posted:
http://www.si5.com/products.php?pID=4038

probably a easier alternative

The problem with this is that it is just as expensive as the AMP9. I was hoping to be able to take something out of a head unit I already had or go to a local scrap yard and pick up some for cheap.

ArcaneDreams · 03-22-2008, 10:10 PM

It is very unlikely you will be able to take specific parts out of your head unit to amplify things from your PC. You would need to know a lot about the head unit, as well as a lot about electronics.
There are not too many diagrams as to what is what in specific head units that you can reference.

I would say go with the link posted above. It isn't as expensive as the AMP9. The AMP9 is around $100 USD, while the item above is only like $75.

I will probably get one of those myself until I have money to get a real amp and some real speakers.

scott_fx · 04-06-2008, 03:44 PM

Quote: Originally Posted by bl3nd3r

The problem with this is that it is just as expensive as the AMP9. I was hoping to be able to take something out of a head unit I already had or go to a local scrap yard and pick up some for cheap.

I just picked up one of these to experiment with and replace my dared mp5 amp at work (so i can take it home)
http://www.partsexpress.com/pe/showd...number=300-958

on sale for $50

stonestatue · 04-06-2008, 05:12 PM

Is it possible to put two of these sound cards in a carputer for four channels, or can four channels be used on just one?

scott_fx · 04-08-2008, 05:10 PM

you should use two.

also just found this:
http://cgi.ebay.com/ws/eBayISAPI.dll...S%252BI%252BSS

is another cheap alternative that can probably be powered of an m2-atx psu

FusionFanatic · 04-08-2008, 09:09 PM

those mini-amps/amp-cards are fine for home computer usage, but will be useless in a car. they're simply not powerful enough. 10-15w will not even match a modern factory radio (if a factory radio can outperform something then you know it's bad!)

unless you're an electronics genius, I doubt you would be able to simply remove the amp from a head unit since it's integrated into the main circuitboard. but you could remove all the "guts" from the HU, remove the CD player mechanisms and mount the main circuitboard (and any other components necessary for the HU to operate) inside your PC case. IMO, this would not be worth the effort but I'm just giving you some ideas.

if you want to use a HU to amp your speakers then just keep the HU in tact and mount it in the glove box, under the dash, under a seat, etc. you don't have to take a HU apart to keep using it, just hide it somewhere

ArcaneDreams · 04-08-2008, 09:53 PM

Quote: Originally Posted by FusionFanatic

if you want to use a HU to amp your speakers then just keep the HU in tact and mount it in the glove box, under the dash, under a seat, etc. you don't have to take a HU apart to keep using it, just hide it somewhere

This would be weird to adjust to. He would have to set his volume on his head unit to a fixed position. I think it would either limit his total output (volume on medium), or it would sound really static-like (high volume on head unit, and low volume on PC).

Just get an amp. If you cannot afford an amp..then think about abandoning the car PC idea and just get a regular head unit.

JimmyFitz · 04-08-2008, 11:07 PM

http://www.davidnavone.com/cart.asp?24&cat=5

(scroll down some, it is the fourth item listed)

20 X 20 STEREO AMPLIFIERS
AMP-100 $39.99

This little power amplifier was designed for boosting the low
signal outputs of MP3 Players, IPODs, etd. up to speaker level.

scott_fx · 04-08-2008, 11:42 PM

Quote: Originally Posted by FusionFanatic

those mini-amps/amp-cards are fine for home computer usage, but will be useless in a car. they're simply not powerful enough. 10-15w will not even match a modern factory radio (if a factory radio can outperform something then you know it's bad!)

unless you're an electronics genius, I doubt you would be able to simply remove the amp from a head unit since it's integrated into the main circuitboard. but you could remove all the "guts" from the HU, remove the CD player mechanisms and mount the main circuitboard (and any other components necessary for the HU to operate) inside your PC case. IMO, this would not be worth the effort but I'm just giving you some ideas.

if you want to use a HU to amp your speakers then just keep the HU in tact and mount it in the glove box, under the dash, under a seat, etc. you don't have to take a HU apart to keep using it, just hide it somewhere

I highly doubt that a oem headunit is putting out more power then 8 watts (cleanly). If he's keeping stock speakers or going with something like infinity high sensitivity coaxials and is not looking for amazing sound, i don't see how that ebay amp would be a bad idea. i'm tempted to just get one to play around with. hell... maybe get one to power my tweeters in my other car if it sounds good :-)

durwood · 04-10-2008, 08:00 AM

Search for LM3886 chip amps. They are fairly cheap IIRC. You just need to find a PSU to power it-this is where you might run into $$. Might want to look on DIYA for more info.

http://www.jameco.com/webapp/wcs/sto...oductId=192516

Only 1 channel though.

scott_fx · 04-12-2008, 03:45 AM

i got the sonic impact in today and it's a decent little performer. i've hooked them up to some a/d/s monitors at work and a/b it with my dared mp5 and upon initial listening (it's said that the amp needs some break in time) it was very solid performer considering the dared (still budged) costs about 8x as much, the highs were a little crisp compared to the dared (but in it's defense, the si amp doesn't have the tube pre-amp stage) Mid range was pretty similar with a nice open soundstage but the dared edged out on bass.. but it did great for $50.

I have been playing around with both amps at home now and have hooked them up to a tang band 3" full range in a 5" square cube, a zaph-audio design full range using the hi-vi 3" and also a definitive technology bp-10. With the amp pushing the bp-10's i was actually amazed at even the bass that this thing was putting out. I put on TOOL's "prison sex" and it filled out the bottom end nicely. Even with putting in Common Market's "g'dang diggy" the first bass drop was pronounced but the song sounded 'hollow' to me. Next I put on Cyndi Lauper's "true colors" and this amp shined with this song.

I spent the rest of the night playing various favorites and it ran through the paces just fine. Overall I'm happy with the product so far, posed with the option I'd stick with my dared but it's not an option for what you're trying to do. I would say if you want a nice amp for better then stock sound, ultra compact footprint and good value... then this is a great option.

I'm definately going to have fun with this amp. I'm going to drop it into a nicer case, add a dac that i have laying around and also probably use a stepped attenuator as well.

randyre · 05-01-2008, 10:45 PM

I'm finishing my install and also am looking at eliminating the head unit. Problem I see so far is that it appears that when you use the onboard sound card and an amplifier, you loose the ability to fade from to rear, all you get is left and right stereo. Is this correct? Or am I missing something?

BTW, that amp above, coupled with the volume knob looks like a good comprimise between a head unit and a carputer.

Randy

bl3nd3r · 05-02-2008, 10:15 AM

Quote: Originally Posted by randyre

I'm finishing my install and also am looking at eliminating the head unit. Problem I see so far is that it appears that when you use the onboard sound card and an amplifier, you loose the ability to fade from to rear, all you get is left and right stereo. Is this correct? Or am I missing something?

BTW, that amp above, coupled with the volume knob looks like a good comprimise between a head unit and a carputer.

Randy

Yes you would need 4 seperate channels coming out of the computer to allow for independent control of all the speakers (FL, FR, RL, RR). You would then need it to be fed into a 4-channel amp to control all four speakers independently.