[BavariaBarbarian]

Hi there!

I've recently (finally... ) finished my Pimeta.
(Btw. I like how it sounds quite a lot, and tip my hat to Tangent and the great people here in the DIY-section.)

It runs off a 20V AC Power-adapter regulated by a Tread.
Now I figured it would be convenient to also power my Ipod through the Tread (especially as I've lost the original Ipod-PS on my last holiday-trip).

Now if I hook up the Ipod and switch on just the Tread, not the amp, all's fine: the Ipod lights up and charges.
If I connect just the Ipods lineout, all's well also: I can hear the music play.

However if I connect power and audio, the sond fails. It gets really soft and distorted. - Sounds like a grounding problem, and indeed, I discovered that the Ipod internally connects audio-ground to firewire-ground (and that's also V-).
So signal-ground is suddenly the same as V- of the power supply and while I'm not sure I completely understand what this does to the Pimeta circuit, it sure stops it from working.

Now what can I do to make this work?

Many thanks in advance,

Mat

 

[MisterX]

What happens when you connect the V- to the virtual ground on the amp (in ground) via the Ipod?
It is no longer half the supply voltage right?

 

[BavariaBarbarian]

Ah! Pretty obvious, actually...

I think I understand.

So if i connected the Ipod to V+ and Vground, that would solve my problem, right? Give the Ipod ~10V, leave vground in order.
But the TLE railsplitter can't source the amount of current that the Ipod draws...
So I'd have to use another virtual ground circuit?

Doh!

 

[skyskraper]

id just go get another ipod charger, theyre cheap on ebay or the like anyway. and you'd be able to charge your ipod elsewhere too.