TLP as headphone amp.

simgrant · « **on:** 21 Apr 2005, 11:17 pm »

Hello fellow Aksaphiles,

This might be a silly question, but could I use my TLP to drive a a pair of headphones, using a cd as the source. I am not sure what the output impedance of the TLP is but it must be pretty low.

Regards, Simon.

SamL · « **Reply #1 on:** 22 Apr 2005, 01:45 am »

No sure if TLP will be able to drive a headphone but an alternative is to drive the headphone with your aksa power amp as per Elliott's site http://sound.westhost.com/project100.htm
It will add quite a bit of complexity into the case work & wiring.

Have fun,
Sam

simgrant · « **Reply #2 on:** 22 Apr 2005, 02:08 am »

Thanks SamL,

I had overlooked some previous threads before posting which I have since found. I had wanted the TLP to act as a standalone headphone amp but it seems a buffer is required. I will have to look further into the threads for recommendations.

Regards, Simon.

AKSA · « **Reply #3 on:** 22 Apr 2005, 07:11 am »

Hi Simon,

Thanks for dropping in!

You are right, however, and you will need a buffer. The Zout is 130R, which should be OK for headphones over 2K, but no good for ordinary 32R or lower.

There are simple opamps which would do the job; you could use an 1875 for this job, but it's basically a power amplifier. It will sound OK, but not quite as good as an AKSA!

Cheers,

Hugh

simgrant · « **Reply #4 on:** 23 Apr 2005, 07:14 am »

Thanks, Hugh,

an LM1875 would have huge amounts of power. I remember reading a project by someone called Sheldon Stokes where a headphone amp used a HQ opamp input and class A mosfet output. But then a good old bipolar stage should be fine as the TLP won't mind a transistors low input impedance.

Regards, Simon.