All transistor amps benefit from being left on 24/7. However, amps that are Class A or biased in high-Class A are best turned off at the end of listening due to excessive heat. These benefit from a prior warmup (1/2 to 1 hour) before use.
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?..
12 responses Add your response
They are biased A for the first 30 as I recall, and do generate enough heat to require AC for extended listing sessions. I understand that the cables should not really make a difference in the amount of warm up time the amps require, but now they require the time and before they didn't to become listenable....an odd occurrence indeed.. |
@stevea11757 If I had to guess, were your former cables more veiled over, less transparent sounding, as compared to your new cables? What were your former cables by the way - and were they old bulky copper cables from 80s/90s, or early to mid 2000 years by chance? If so, your experience is not unreasonable. Now you can hear it more so with the new cables during first 60 minutes of warmup of the 260.8, and the rest of the system warming up if you are turning all of it on cold and listening in 5 min. Nobody I know listens critically to Pass < 60 min. Several comment it’s not great until at least 4-8hrs warmup. Others, as already mentioned run it 24x7. All my former SS Mosfets based amps were better @8hrs+. If I left them on 24hrs+ letting the transformers really become heat saturated, another level achieved in some perplexing ways. Others have mentioned this here. Often noted for .5 and .8 amps from Pass. Same for older Threshold and some of the Adcom and Nakamichi Stasis designed amps too. I too use my MD tuner for warmup, and sounds pretty rough until it’s been warmed up for at least 45-60 min, minimum. Same as the 260.8. Sure, I can go throw a pair of high capacitance veiled over copper interconnects or [longer] veiled speaker cables on my current system (did it this weekend) and make it sound tolerable first 5-30 minutes of warmup, it’s just masking what’s there. Then, go put ultra transparent ICs or speaker cables back on and it sounds horrible the first 5-15 minutes of cold startup. I bet your new cables are revealing more of what is "there" during cold startup. Just a guess... I recently sold a pair of my last and most lush and veiled over Cardas Golden Cross interconnects to a guy with a Pass 260.8 [he wanted to "take the edge off" with streaming high resolution content]. As edgy as a cold MD tuner. Found a review on your cables - said to be much more revealing ?: "Dynamics were explosive. Yet, there was detail that I never heard with any wire in my experience. This detail was sorted and separated so well, I was floored." |
The previous cables were Straight Wire Rhapsody S, I took advantage of their trade in which allowed full msrp trade in on the new pair. So money wise it was kinda of a no brainer as the cash outlay was under what I was looking to spend on a used pair to upgrade. I did not want to drop a bundle without being able to hear them in my system as I am also in need of a 3m pair of xlr's as next upgrade. I would not say that they were veiled if anything a little lean on the bass which picked up with their replacement cables. |