Update: after some months of mulling this over, I decided it would be an interesting exercise to see what the tubes in my DP-777 actually are before further considering replacing them. As I've stated earlier, I'm no kind of electrical engineer, so just the process of getting into the works to examine the tubes turns out to be rather daunting. There are clear plastic plates on either side of the top, under which some of the workings (including the tubes) are visible, but I don't think these plates are easily removable, so It looks as if you have to remove the back of the unit to get inside, despite the dire warnings about the risk of electric shock. I got as far as removing the thin back plate, but underneath that is a far more substantial metal plate that anchors all the input and output receptacles, all held in place by a number of hex-drive bolts. At that point my courage failed me, as I figured that all the receptacles are wired in place and it's not something I feel comfortable disturbing. For any of you who have replaced the tubes in this DAC, is this the procedure you used? Is there a less intrusive way to get at these tubes? The prospect of having to send it to iFi/AMR (assuming they even still service these DACs) for this is unappealing. Thanks.
AMR DPP-777 DAC tubes
This might not be, strictly speaking, a "digital" question, but I've read quite a few threads about the merits (or non-merits) of different tubes in various components and their effect on the sound. Opinions seem to be all over the place and for a non-technical person like me, a lot of the discussion goes over my head. I have an Abbingdon Music Research DPP-777 DAC (original version, not the SE version) with its original tubes, and it's had quite a bit of use in the 3 years I've owned it. It still sounds extremely good, but I'm wondering if there would be a noticeable improvement if these tubes were replaced with, for lack of a better way to express it, better ones. The tubes are 6N11, and I don't know who the manufacturer was. Is it worth my while to pursue this as an affordable upgrade path? Thanks for your opinions.