What speakers are you using? I demoed the DNA-1 in my system about 10 years ago and would never have described it as fatiguing. It's a solid and well-respected amp, and is capable of a firm bass and articulate mids. I just found it to be a little uninvolving compared to my tube amp, but it really wasn't bad.
You have well-respected electronics that should sound good. However, I suspect the synergy just isn't there, and I'm suspecting it's the TAD 150 / DNA-1 pairing, although the output impedance of the TAD 150 is < 600 ohms and the input impedance to the DNA-1 is 100K ohms, which should be fine. That is, of course, if the amp is appropriate for your speakers, although the DNA-1 should drive most speakers well. Are you using Apogee's or some other difficult to drive speaker?
This person on Audiogon found your exact pairing to sound good with Vandersteen speakers.
Can you borrow another source and/or preamp to experiment? Also, try calling Steve McCormack; he will likely be able to guide you here, as well.
Michael
You have well-respected electronics that should sound good. However, I suspect the synergy just isn't there, and I'm suspecting it's the TAD 150 / DNA-1 pairing, although the output impedance of the TAD 150 is < 600 ohms and the input impedance to the DNA-1 is 100K ohms, which should be fine. That is, of course, if the amp is appropriate for your speakers, although the DNA-1 should drive most speakers well. Are you using Apogee's or some other difficult to drive speaker?
This person on Audiogon found your exact pairing to sound good with Vandersteen speakers.
Can you borrow another source and/or preamp to experiment? Also, try calling Steve McCormack; he will likely be able to guide you here, as well.
Michael