If you're looking for the most holographic imaging you should consider pairing the 25th Anniversary Zen with a good pair of efficient single driver speakers. One of the most classic pairings is with
Omega Super AlNiCo Hemp drivers. I think single drivers will sound even better if you can augment the bass with a sub or two that have a high crossover range to bring in the mid-bass.
Also a few things to consider:
1. The 25th only has 1 source input, so if you have 2 sources you will need to either swap cables each time you change from your TT to your DAC (which is cumbersome IMO), or get a Decware Zen Switch Box that will add more inputs for sources, or use it the 25th with a preamp.
2. Also, the 25th is an amp with a volume attenuator in its purest form, so in order to use a TT you will need a stand alone phono stage or again a preamp that has a built in phono stage.
3. I'm not sure how great a match it would be with Naim as a pre + 25th Anniversary as I would think they are built and designed with different sound parameters in mind. I've never heard that pairing, it could sound great, but I just don't know. I can say though it pairs really good with McIntosh preamps and of course Decware's own preamps.
4. Another option that you could do ... is instead of the 25th Anniversary you could get the Super Zen Triode SE84UFO2 (as you can get it with 2 sets of inputs) and then have the 25th Anniversary mods done to it. This will sound pretty much like the 25th, but more flexible as you can hook a DAC and phono stage to it without having to swap cables each time you change sources.
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