Pass 260.8 owners...Question

Having owned my 260.8 for some time (year and a half) and at some point I determined that I was in need of a speaker cable upgrade. I was using a duel run of cables to each of Shahinian Acoustics Hawks, one for the sub enclosure, one for the HF module. I was happy enuf with the sound, but thought moving up would allow the subs to open up a bit as I felt they were a little laid back, there but barely.

I up graded to two runs of Straight Wire Crescendo 3's. Jerry from Straight Wire told me to expect a 100 hour break-in after which they should be a major improvement. Well, immediately after installing, the difference was noticeable that continually got better over time.

 As a lead in, the cables I replaced sounded fine within 5 minutes of starting up the amp as did the new cables.

 However, as I approached the 100 hours, I noticed something odd. At first, I was unable to put my finger in it, but after several listening sessions it became quite apparent that the sound when the amps were cold with the new cable fully burned in, was for lack of a better work atrocious. At first, I would just listen for a half an hour and then make an excuse to get out of the room and go do something else shutting everything down to explore the problems later. The next time, when I started the system, I listened for a bit, same reaction, hf sounded like they were playing in a fish tank. I left on this time streaming from my Magnum Dynalab 809 on low volume and returned after an hour or so to the sound I was accustomed to hearing. Same thing tonight, started and left the room after setting it to play for an hour or so unattended. I returned to a full dynamics that I know the system is capable of.

 Now, I know that a amp needs to warm up to stabilize, but to go from unlistenable bliss, this is something I have never encountered before the speaker cable upgrade, they always sounded great within 10 minutes, now not so much…

 Anyone else running Pass mono's run into this situation? I went as far to ask for recommendations for music to check the system out with to make sure that I was not losing my mind, but apparently, I am not…

 Normal?..