PS Audio's Opinion of 'Leave Them On?'


From the 98 manual:
Power Switch
The power switch located at the far left on the SLP 98 front panel functions in the following manner: …
OFF Removes all AC voltages from the SLP 98 preamp deck. …
Provides DC voltage through individual regulators to flow to the filaments of the preamplifier stage. (The SLP 98 may be left in the stand-by position at all times to keep the SLP 98 in a warmed-up, ready- to operate mode without B+ potential. Operating in this fashion gives peak performance after only a few minutes of operating time).
… OPERATE Brings up full potential DC voltage within one minute.

Sounds like standby applied power to the tubes but not full on? Someone else will be able to confirm.


I actually leave them on but will turn them off if I’m out of the house for a week or more. I don’t know if this is coincidence, but my P10 died in the middle of the night after 5 years of service (tried to reboot and would never finish the reboot) so I had to send it back to Boulder. So . . . I don’t know if my power cycling induced the failure or it just died on its own. Apparently the I/O circuitry died on the P10’s processor. It was weird when it failed at 2:30 AM: It just tried to restart and wouldn’t ever complete the reboot, no matter how many times I tried to recycle the power. We do have power glitches in our neighborhood during wind storms, so I have no idea if those were contributory to the problem or not. But it might be total coincidence that my power cycling affected the I/O circuit. Dunno. But it’s fixed now.

No I didn’t trade up to the P15 just yet, I had just bought the Iconoclast speaker and interconnect cables, so that blew my budget for the year. I did get an equivalent sonic upgrade with the new cables to what’s being reported with the P20 improvements, so I’m not unhappy with my decision to just fix the P10. But I can save the P20 for later after I get the AN2’s.



A few years ago, we lost power for about 5 days due to wind damage. However, I noticed that my system seemed to sound better after power was restored and given sufficient warm-up. Then I remember what the manual said about the clean wave in my power plant, that after a while a system can sound” stale”. The clean wave in my P5 is said to degauss magnetics. I keep my components on standby, but every so often I power the whole system off for a while and notice a bit more “sparkle” to the sound.

So, I have this hypothesis: the individual components (resistors, capacitors, etc.) in our electronics reach a steady state after a certain amount activation. However, they do not remain exactly at a steady state indefinitely. After weeks or months, they change in small ways. These small changes accumulate, and their combined effect is produce that “stale” sound. The effect of powering down the electronics is to permit those small changes to dissipate eliminate those small changes.

I can be totally wrong on this but I find it hard to believe that resistors, capacitors, transformers etc. can remain on for months or years and no change in any way.


Just go by the manual. I was reading thru the manual for a ss preamp that I bought for a second system. In it, the mfr. recommends that no critical listening be done until the unit has warmed up for 24 hours(!!) and that recommendation starts every time the unit is switched off. Since the unit draws only 25 watts, it’s not a big deal.


I find this happens too. I suspect it has to do with clocks, as the gear that in my experience seems to be affected are things like digital sources, DACs, and maybe even my P15s?

So I tend to re-boot everything roughly weekly, along with a P15 Cleanwave run.

Greg in Mississippi


We had a scheduled power outage of a few hours over night but it coincided with being away for 4 days. I’ve not had my entire system offline for a good while, not long enough to get cold anyway.

Today is day 4 since it’s been powered back on and playing nearly continuously and it’s just now beginning to sound back to normal to me.


Funny, I have always wondered what the Standby Position on my SLP98 was for, but obviously not enough to read the manual.

I usually just turn mine on an hour before I start any serious listening.