VDH Colibri XPP. Best Load impedance?

Hi Geoch,

very interesting that your MC Step Up is working because the internal impedance is 500 Ohm.

I tried with 200 Ohm but for my opinion the best is between 600 and 750 Ohm.

I've check a resistance of 9.6 Ohm (R) & 9.8 Ohm (L) on my XPP with my Protek 505 digital multimeter.

I'm using the input tap of EAR MC4 step-up that is recommended for 12 Ohm Nominal Input Impedance. This tap has a Natural Impedance of 145.1 Ohm and gives a gain of 25.1 db that elevates the 0.22mV of the XPP up to 3.96mV (x 18 times).

Also I've made some comparisons using the MC4's input tap that is recommended for 6 Ohm Nominal Input Impedance. This tap has a Natural Impedance of 81.6 Ohm and gives a gain of 27.6 db that brings to the output 5.28mV (x 24 times).

I have the (old) € 6000 standard XPP model of 0.22mV output
There is the (new) € 8000 Platinum model with FOUR LAYER windings of 0.38mV output. But this one is offered with Titanium or Blackwood body.

Maybe the 500 Ohm it is a case of misunderstanding by VDH himself. Α mistake in translation is not very unusual.
Perhaps he means the Optimum load impedance as he is probably referring inside your XPP box. (Οn my box recommends 200 Ohm).

Hi,

I have the new one with 4 Layer.

I am not sure but I do not think that VDH is making such a mistake.

Anyhow with 200 Ohm it sound not very good more like a CD.

best

Josef

I agree with Geoch. I don’t think the internal resistance of the Colibri XPP can be any where near 500 Ohm. While the resistance of platinum maybe a little higher than copper, it can’t be that much higher.

I had, and still have, the 0.22mv version of the XPP, and come to think about it, I believe the 200ohm loading I was using was recommend by VDH, by the hand writing in the box.

JPetek,

How do you like the XPP comparing to your Colibri XGP? I have a XGP ref and enjoy it very much.

THanks