The real thing to consider, if it hasn't been said before, is that the stratos has a 10K input Z, which may be a bit low for *many* tube preamps. I think you need to take a close look at the output Z of the tube pre you are considering and make sure it jives. Ask the maker if necessary. Ask Klaus. The tempest I heard once in an unfamiliar system but thought it sounded great and no grit to speak, so it is a consideration as well.
Hey
JoshK,
So would it be safe to follow the "phono cartridge" loading rule of thumb regarding amp and preamp? Say, for a 100 ohm cart impedance, it is better to have 10 times of that the cart will "see" to the phono preamp.
If yes, then for a 10k (Stratos) input Z, you need not more than 1k as the output Z of the preamp.
I have the Supratek preamp powering my Stratos. But when I ordered it, I took the liberty to get one with a 500 Ohm output Z. The combination is great and it sounds to me that the preamp does not even know it is driving something, if you know what I mean.
firestic,As for the MAD preamp, I have the Octal 6A Triplex with all Hovland caps, Rikens, and Blackgates. I have nothing against Dr. Lloyd and I think he's preamp sounds great. But mine developed a nasty hum that I cannot take away no matter what I do. I ended up building another box to separate the PS transformer to at least make the hum tolerable. Maybe it is just my luck, who knows. For the price of the MAD, it is a no brainer to try it. Besides, you can return it if you do not like it.