Diy Car Audio Preamplifier for Aux-in

_abhay_ · 24th May 2008, 13:43

Need a preamp to connect between the Aux port and the audio source. I usually connect my cell phone to the HeadUnit in Aux mode, i have to pump up the volume to make it audible hence the need for a preamp arises. I Also tried to change the stereo to stereo cable to a better quality thinking that was dropping the voltage but it didn't help.

I believe there is a impedance mismatch which is restricting max power o/p, hence a preamp is my requirement.

After searching the net for a while I came across a car preamp on ESP [ elliot sound products] . I am not able to understand the concept of Artificial earth and why it is required. Is getting signal earth [ ground ] so difficult in a car or its just the body ?

If any one has came across this problem and found a DIy solution please share.

HU - Pio 5950
audio source - SE W580 or MP3 player

bmdesai1987 · 24th May 2008, 21:54

a 2 channel amp will do the magic. just install a 2 channel amp from a reputed brand and installer and then u wont need to PUMP UP the volume.

greenhorn · 24th May 2008, 22:24

yup, a single op amp based stage should be more than adequate, I'm not sure whether the aux input and the PSU share the same ground. I think it will be simpler to use a battery instead.

one 9V battery, One Dual channel OP amp IC ( preferably FET, since they are lower power)
and some resistors to set the gain.

PS : google for CMOY to find out more

low_bass_makker · 25th May 2008, 01:30

Quote:

Originally Posted by _abhay_

HU - Pio 5950
audio source - SE W580 or MP3 player

Conneting these two sources would not be a problem. where are you connecting the hu from. And what cables are you using to connect the same.

Dhar's · 25th May 2008, 10:28

Increase the SLA to maximum.
Check the Aux cable for polarity.

I use my SE W810i to Pio DEH 5750MP without any issues.

_abhay_ · 25th May 2008, 14:05

The cable I am using is a Stereo to stereo cable, one end goes into the HU and other in the handsfree connector [ I disconnect the earphones ] 5950 HU has an aux-in port on the rear panel. SLA is at max for auxin

Dhar are you getting a good bass response, as good as playing a CD ? i doubt
using the IP-bus port will be any good ?

Dhar's · 25th May 2008, 15:59

@abhay,

I am using a IP-bus to RCA cable. I couldnt get a RB10 or RB 20. Hence it was custom made. The bass response is good. Maynot be as good as playing the same track from CD but the difference is negligible.

If interested in DIY the following link might help.

Gutterslide.com - Pioneer IP-BUS Hack

_abhay_ · 27th May 2008, 00:47

I also have a carputer project in pipeline. Hence was looking for a preamp with channel switching. switching is not an issue , preamp is as am not well versed with analog circuits. Preamp should enhance the bass response

dhar can you post some pics of your ip-bus connector cable if you have on your pc.I had 1 failed attempt
I should soon get PCB etched for Rod Elliots car pre-amp ckt . not sure if it will work good

Dhar's · 1st June 2008, 12:31

Sorry abhay. I dont have the picture with me.

24th May 2008, 13:43	#1
_abhay_ BHPian Join Date: Nov 2007 Location: mumbai Posts: 38 Thanked: 4 Times	Diy Car Audio Preamplifier for Aux-in Need a preamp to connect between the Aux port and the audio source. I usually connect my cell phone to the HeadUnit in Aux mode, i have to pump up the volume to make it audible hence the need for a preamp arises. I Also tried to change the stereo to stereo cable to a better quality thinking that was dropping the voltage but it didn't help. I believe there is a impedance mismatch which is restricting max power o/p, hence a preamp is my requirement. After searching the net for a while I came across a car preamp on ESP [ elliot sound products] . I am not able to understand the concept of Artificial earth and why it is required. Is getting signal earth [ ground ] so difficult in a car or its just the body ? If any one has came across this problem and found a DIy solution please share. HU - Pio 5950 audio source - SE W580 or MP3 player
	() Thanks

24th May 2008, 21:54	#2
bmdesai1987 BHPian Join Date: Nov 2006 Location: Bharuch, Gujarat, India Posts: 131 Thanked: 2 Times	a 2 channel amp will do the magic. just install a 2 channel amp from a reputed brand and installer and then u wont need to PUMP UP the volume.
	() Thanks

24th May 2008, 22:24	#3
greenhorn BANNED Join Date: Apr 2007 Location: KL-01 Posts: 7,878 Thanked: 4,910 Times View My Garage	yup, a single op amp based stage should be more than adequate, I'm not sure whether the aux input and the PSU share the same ground. I think it will be simpler to use a battery instead. one 9V battery, One Dual channel OP amp IC ( preferably FET, since they are lower power) and some resistors to set the gain. PS : google for CMOY to find out more Last edited by greenhorn : 24th May 2008 at 22:32.
	() Thanks

25th May 2008, 10:28	#5
Dhar's BHPian Join Date: Dec 2006 Location: QLN/TRV/DXB Posts: 419 Thanked: 628 Times View My Garage	Increase the SLA to maximum. Check the Aux cable for polarity. I use my SE W810i to Pio DEH 5750MP without any issues.
	() Thanks

25th May 2008, 14:05	#6
_abhay_ BHPian Join Date: Nov 2007 Location: mumbai Posts: 38 Thanked: 4 Times	The cable I am using is a Stereo to stereo cable, one end goes into the HU and other in the handsfree connector [ I disconnect the earphones ] 5950 HU has an aux-in port on the rear panel. SLA is at max for auxin Dhar are you getting a good bass response, as good as playing a CD ? i doubt using the IP-bus port will be any good ?
	() Thanks

25th May 2008, 15:59	#7
Dhar's BHPian Join Date: Dec 2006 Location: QLN/TRV/DXB Posts: 419 Thanked: 628 Times View My Garage	@abhay, I am using a IP-bus to RCA cable. I couldnt get a RB10 or RB 20. Hence it was custom made. The bass response is good. Maynot be as good as playing the same track from CD but the difference is negligible. If interested in DIY the following link might help. Gutterslide.com - Pioneer IP-BUS Hack
	() Thanks

27th May 2008, 00:47	#8
_abhay_ BHPian Join Date: Nov 2007 Location: mumbai Posts: 38 Thanked: 4 Times	I also have a carputer project in pipeline. Hence was looking for a preamp with channel switching. switching is not an issue , preamp is as am not well versed with analog circuits. Preamp should enhance the bass response dhar can you post some pics of your ip-bus connector cable if you have on your pc.I had 1 failed attempt I should soon get PCB etched for Rod Elliots car pre-amp ckt . not sure if it will work good
	() Thanks

1st June 2008, 12:31	#9
Dhar's BHPian Join Date: Dec 2006 Location: QLN/TRV/DXB Posts: 419 Thanked: 628 Times View My Garage	Sorry abhay. I dont have the picture with me.
	() Thanks