Copper foil around electrolytic capacitors?

[wreeve]

I was just wondering what is the point of copper film/foil placed around the electrolytic capacitors in my PD9700 CD player. Looking at the schematics they are around all the digital power supply smoothing caps, not the analogue. The copper is not connected to ground so I can't see the point in it?
You can't see it from the outside of the player and it's not mentioned anywhere so they must think it's of some benefit?

Keep well,

Will

[Ruach]

The Pioneer PD-95 has copper foils on all the capacitors

[Jennice]

Hmmm... could it possibly be a case of them not wanting people o know what brand/size they use? Or is the text printed on the foil (can't be seen on the pic)?

Jennice

[peranders]

I'm pretty sure you won't get any technical explanation because there is none, but it looks nice and some people think it sounds better. My personal opinion is sugarpill.

[Extreme_Boky]

I tried copper sheets on top of surface mount 1704 DAC's and was able to easily notice more relaxed sound. There's even bigger difference with DIL chips, like TDA1541A, if using copper sheets sandwich: one plate beneath, the other on top. The connection between these two plates, as well as connection of this sandwich to PCB ground plane, makes the difference as well. This is easy to notice especially on NOS DAC which is very revealing of EVERYTHING.

I haven't tried copper-wrapped capacitors, but from the experience above, I recon there should be audible difference in sound, all for better. I suppose the only way would be to try and see...

Extreme_Boky

[phase_accurate]

I don't see how this might help. There is more than one difference between caps and ICs. The case of the latter doesn't provide any electrical shielding at all.

The outer can of elcaps is made of aluminium (not that much a worse conductor than copper BTW) which is usually connected to the negative wire/pin. I don't see how an unconnected copper shielding could have any effect then - apart from looking cool.

Regards

Charles

[Extreme_Boky]

The outer can of elcaps is made of aluminium (not that much a worse conductor than copper BTW) which is usually connected to the negative wire/pin. I don't see how an unconnected copper shielding could have any effect then - apart from looking cool.

I think the trick is in using copper which has natural, warm sound full of harmonics and texture, instead of aluminum can only. This approach was very popular with beautifully rich sounding CD players made by TEAC. They were full of copper-wrapped capacitors. What beats me is the fact that the copper wasn't connected to ground(???) Injecting the jitter purposefully to smooth-out the sound?

Extreme_Boky

[Bas Horneman]

If the aluminium outer is connected to earth..then the copper is too, because the copper seems to be soldered to the top of the caps.

[peranders]

Originally posted by Extreme_Boky
I think the trick is in using copper which has natural, warm sound full of harmonics and texture,..

Can you explain? In what way has copper a certain sound? Have you tested other metals too so you really know the difference?

[anatech]

The copper is not bonded to any ground on these players. Like everything else Pioneer does - it's marketing only. Fleecing the pulic again.

The copper vs aluminum sound .... oh god, let's not debate this now. I knew some just had to launch this while reading through the thread. It would have been me if peranders hadn't jumped on it.

-Chris