lamm lp2 loading question


There are many reviews and people here that refer to the Lamm LP2 phono preamp as having a MC Load of 40ohms. However, the Lamm website lists it at 400. 400 ohms would be rather flexible but 40 ohms would not be for most cartridges. 40 ohms seems awfully low for the only setting. Can anyone explain the discrepancy?

thanks

michael
radioheadokplayer
I spoke to Vladamir himself and he says its 400. The earlier information regarding 40 was an error even though it was alluded to in the audiophile rags!
My understanding is that Lamm has 1:10 SUT inside so its natural impedance would be around 400 ohms. So unless Lamm adds loading resistor or something, 400 ohms would be more likely than 40, I would guess. I am still a bit confusing about SUT and loading myself :)
The default setting on my Kw phono stage is 10 ohms and the external loading I use most is 100 ohms so 40 probabaly will work with most. I would think 400 is too high, at least for the cartridges I have used. YMMV
Why not ask Mr. Lamm? The science of loading an MC cartridge that is "seeing" a SUT is somewhat complex, and I would be loathe to guess what is going on. If the resistive load is situated on the primary side of the SUT, the value "40 ohms" might make some sense.