Is no preamp really better that a good preamp?

I also use a Spectron Musician ii high current power amp to drive Martin Logan Spires.

Hi Rustler.

Your PS Dac has from it's single ended output has 100ohms output impedance at 2.8v from it's "Resolution perfect volume and balance controls"

Your Spectron amp has 50kohm input impedance at 26db of gain.

These are a perfect match for each other to go direct with, and will give you the best transparent/dynamic sound you can get.
By putting a preamp into the mix you are just throwing money away to colour the sound with.

Cheers George

Like many people, I tried to save money and eliminate the preamp. If you're happy with what you hear without it, then good for you. Ultimately I opted for a preamp. I can't remember which Sterophile writer said that "the preamplifier is the beating heart of a system" I fully agree. I'm using a Classe CP700. I can't imagine doing without it.

All true Phusis, but the OP was asking specifically about adding a separate (perhaps tube) pre-amp between both his DAC & phono stage and his power amp.

I submit the answer depends on the components involved. I had a PS Audio DSD DAC and compared to the Parasound JC2 preamp, I initially preferred the DSD direct. After extended listening I felt I lost dynamics and detail. I sold the DSD and Parasound JC2 to purchase a Bricasti M1 DAC. In my system the Bricasti was a definite improvement over the DSD. The dynamics were there, detail, but I still felt like something was missing. I went from the Bricasti M1 directly into my Jeff Rowland 525, to the M1 going into the Jeff Rowland Continuum S2 integrated. It sounds better than ever. I don't know if it's because the amp section of the Continuum is that much better, the added preamp section, or a combination of both. I prefer music with a preamp.