VDH Colibri XPP. Best Load impedance?


Hi,

what is the best Load impedance for the VDH XPP (Platin?

Josef
jpetek
Josef, as stated in several other threads, unless your preamp is sensitive to Radio Frequency Interference (RFI) then the loading will not be critical. If you find that it is, then your preamp is having a problem (and if it were me, I would consider replacing the preamp). Emil_f's suggestion is thus not a bad one.
Hi,

I don´t think youre right Atmasphere. I spoke today with VDH. He told me the best is between 500 and 1kOhm.

The internal impedance is 500 Ohm. For my taste the best is between 500 and 800 Ohm. With 1kohm the result is not good. Too much high´s.

regards

Josef
Very Simple. I want to know if somebody else has a different experience with this Cartirdge. Maybe 5k is the Right? I do not have 5k on my Phonostage.
Well I think your response to Atmasphere above is quite rude.
You asked for advice, then proceeded to dismiss it outright.

The answer to your question is - there is no best load.
It may vary depending on your arm/cartridge combination and phono stage.

The suggested loading on the Colibri I listened to were 100R to 47k. These were written down by VDH in his own handwriting in blue ink.

Personally, I was very happy with 47k.
Loading is, as Dover pointed out, so much dependent on not just the cartridge, but the particular phonostage, that a very specific manufacturer recommendation would not make sense (hence, the wide range Dover mentioned that VDH recommended). I think manufacturer's sometimes make a recommendation just to prevent customer angst and endless inquiries. The 100 ohms mentioned is an almost universal recommended loading (it works well enough for the vast majority of MC cartridges) and is a common figure for MC phonostages that have fixed loading, so it is not surprising that VDH included that figure in his recommended range.

From my own experience, I generally like wide open with essentially no loading (47k is pretty much unloaded). The 500 to 1k that VDH recommends on their website for the Colibre is pretty much unloaded too (I bet few can actually hear a difference between 1k and 47k). If one really "needs" to load below 100 ohms, something is unbalanced with the system/setup. I own a Transfiguration Orpheus L. It has a source impedance of 1 ohm. If one used the 10X formula that some recommend (like Fremer), the proper loading is 10 ohms. That would make the cartridge sound sodden and shut down and would seriously reduce the output of a cartridge that is already somewhat low in output. With something like the Colibri, one is paying big bucks for the spectacularly open, and fast top end of that cartridge--it would be a pity to wipe that all away with excessive loading.

Atmasphere's comments are consistent with what some cartridge manufacturer's have said--loading may be helpful when there are issues with RFI and where the ultrasonic resonangt peak of MC cartridges may overload a phonostage with poor headroom margin. A friend had noise problems with his Hovland HP-200 (caused by RFI). It turns out that the factory default setting is 100k. When we loaded it to 47k, the problem went away.
Thanks for your response.

I don´t know if one of you own a Colibri Platin but my experience with this Cartridge is that he is very sensitive. I own before a VDH Colibri Gold. This cartridge is not so sensitive like a Platin.

500 Ohm is the internal impendace. If I use the formel x10 you need 5k. I started this threat to find out if somebody tested this cartridge with 5k or 10k. A Platin nothing else. A Gold has for example only 38 Ohm!

The reason why is I am looking for a new PrePre. My old own is not a good match for this Cartridge.

regards

Josef
I seriously doubt that the internal impedance is 500 ohms. According to the VDH site, the various Colibri models have a resistance of 21 ohms, 36 ohms and 96 ohms. For all of these models, VDH recommends loading of 500 ohms to 1k ohms. Even 96 ohms is unusually high and 500 ohms as an internal impedance would be unprecedented (as far as I know). See the specifications on this page:

http://www.vandenhul.com/p_A03.aspx
Hi Larry,

I spoke yesterday with VDH himself he confirmed me 500 Ohm! You will not find a Platin on the Web. A Platin is made only through a special order.

Josef
XPP - Colibri plastic body, platinum coils.
Platinum is much more resistive than copper, so the 500 ohms is plausible.
You should probably try and borrow a phono stage that has unlimited loading options eg Klyne 7, that you can try out.
Alternately there are some phono stages that are current sensing and do not require loading at all - eg Goldmund PH3.
You wont find many prepre's with wide loading options as they tend to be old school with loading down for LOMC's.
For my own XPP he recommends an optimum load of 200 Ohms.
I prefer to let it wide open at 47K for both of my phonostages.
I'm using :
1). A current mode active pre-pre with Siemens CCa feeding a RIAA with RCA 12SL7 / RCA 12SN7 / Philco XXB
The TT is : Symphonic Line RG6 with Pluto 9A Prestige.

2). The EAR MC4 step-up feeding a half active / half passive RIAA with Telefunken ECC803S
The TT is : Thorens TD124 II with SAEC WE-308 SX & Zonotone Z-SHELL 10 headshell.

Speakers are : Lowther P6M Ticonal in Carfrae LBH plus an added Seas T35 Exotic Soft Dome tweeter (crossing at 2.6Khz)
Amplifiers are : Berning Siegfried (for T35), 12SL7/6J5/4300B (for P6M)

As an attempt to open up more the midrange, I'm going to substitute the 300B SET for the Futterman H3aa in order to free the P6M from the Output Transformer.
So, you can realise that for my own taste, a havier load for my XPP is out of the question as there is not needed any damping. (Even on my SAEC!)

The cables are all the new VDH 3T series (Cliff, Mountain, Cloud, Air).
The VDH "The Grail" Phonostage, is also current sensing (and I've heard that VDH take a license from Goldmund).
But I'm sure that there is not a problem with the loading, as I've own VDH "The Grail', Einstein "The TT Choise", Goldmund "Mimesis 7 w/phono", CAT SL1, Klyne 7, and many lower level phonostages. Is there any possibility for another reason somewhere in the chain that asks for damping?
I have used the Colibri XPP a few years back with the Pass Xono phono, and settled on 200 Ohm loading. Since that was quite a while ago, I couldn’t remember whether I tried it with 47K Ohm though!
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).
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.
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
JPetek,

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

THanks
Hi THanks,

the XPP is a little bit cleaner then the Gold. For the most LPs the Gold is better. If you have only prefect LP then the XPP is better. The Resolution is higher, the speed is higher and color of the insruments is better, but it is only 5% I think.

You need a very highclass equipment to hear the difference.

Josef
The inductance of the cartridge is what speaks to the loading value. In this case the 500 ohm resistance value is also in question, but even if it were so, the inductance is what interacts with the phono cable capacitance to set up the tuned RF circuit I alluded to earlier.

In short, it appears that Jpetek's preamp section is indeed sensitive to RFI generated by the afore-mentioned RF tuned circuit. So the value he likes is likely going to work only for him as it is dependent on the capacitance of his interconnect cable.