Hi all,
Got my DAC back in short order: upgraded current buffers and op-amps in the current to voltage section, plus a "rewired grounding for quieter operation."
It was quiet before, but I do seem to notice reduced noise, from what I remember, when holding my ear directly next to the speaker cones. (The Ellis 1801 is a relatively insensitive speaker to begin with.) The very soft ground hum in the woofer seems to be cut in half; presumably the other half would just about go away if I had Frank do the same tweak to the preamp.
Anyway, I'm unfortunately unable to create any waves and diverge from the reactions others have already had. I don't know what the current buffer upgrade did soundwise over and above the chip swap, but in any case, yes the difference is quite easily discernible on any track I've listened to dozens-hundreds of times before, and the best way to describe it is an extra filigree or two of resolution, everything drawn into that much sharper focus. Like going from your current hi-def t.v. to the next generation hi-def t.v.
At the price, I'd think no one should pass up the chip replacement, 'tis a no brainer. As for the more expensive buffer upgrade for other Ultra DAC owners, from a sound-enhancement perspective it's certainly still worth imo, at least in tandem with the op amp thingy. Obviously I had no chance to evaluate the two things separately, so Frank would be the one to ask. Thanks Frank!
