#### mpuvdd

Joined Feb 11, 2007
50
Hello everyone,
I'm working on building a small circuit to simply distribute an audio signal from an iPod, to two headphones. How would I go about balancing the headphones (cause they could have different resistances), and do you think that the signal would need amplification?
Thanks for all the support,
mpuvdd

#### mozikluv

Joined Jan 22, 2004
1,437
here's a very simple circuit for that. improvements are welcome

moz

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#### bloguetronica

Joined Apr 27, 2007
1,372
here's a very simple circuit for that. improvements are welcome

moz
The headphone drivers have 16Ohm each. Did you took that into account? It seems that a lot of signal will be lost.

#### Ron H

Joined Apr 14, 2005
7,014
You can buy them with individual volume controls for around $5 -$10 US. Anything you can build would be big and ugly. Google "headphone splitter volume control".

#### mpuvdd

Joined Feb 11, 2007
50
Cool, well alright, I geuss I'll probably buy one since they're so cheap.
Thanks for all the help guys.

#### Ashok Gupta

Joined Sep 25, 2007
3
simply connect the two headphones in parallel.
There is no need of amplifying the signal as power requirement of the headphones is very low.
I think that there is only little variation in the impedance of two headphones.So u may match the impedance but it is not necessary.

#### Ron H

Joined Apr 14, 2005
7,014
simply connect the two headphones in parallel.
There is no need of amplifying the signal as power requirement of the headphones is very low.
I think that there is only little variation in the impedance of two headphones.So u may match the impedance but it is not necessary.
If the headphones are from different manufacturers, or are just different models, the impedances could be very different.

#### SgtWookie

Joined Jul 17, 2007
22,210
If there is an impedance mismatch, the audio signal will be distorted; particularly at higher volume levels.

The impedance of iPod headsets is 32 Ohms; standard headsets are 4 or 8 Ohms. Obviously, the iPods' output was designed to work optimally with an iPod headset; I can only surmise they chose 32 Ohms as a power-saving and/or weight-saving feature.

In order to properly match other headsets, you'd need to use a matching audio transformer at the very least. Attempting to connect a low-impedance headset would certainly result in a great deal of distortion at higher volume levels.

As a reminder; keep the volume low enough so that you can hear ordinary conversations above the music - otherwise, you will likely cause irreversible hearing damage.

#### Brennn10

Joined Sep 13, 2007
5
could I use 2 3.5mm line sockets, connected to a male headphone jack?

#### Brennn10

Joined Sep 13, 2007
5
So I stripped my stereo plug, now how do i connect it to the two stereo inputs?

#### SgtWookie

Joined Jul 17, 2007
22,210
So I stripped my stereo plug, now how do i connect it to the two stereo inputs?
A stereo headphone will have three or four connections. One or two are signal ground, the others are +right and +left.

A 1/8" stereo plug has three connections. There are three areas of connectivity on the plug; the tip (+left)), a band near the tip (+right), and the signal ground.