RepublicOfTexas69
Member
In standby mode for clarification.
Switched to Class D or get left behind?
- Thread starter nc42acc
- Start date
Randy Myers
Well-known member
Ok, makes more sence
.Mr Peabody
Well-known member
Yep, I always leave mine at least in standby. I had a Pass Labs amp I left full on all the time. It was like a tube amp that it didn't sound it's best until about 40 minutes of operation so I got to just leaving it on. Unless I was going to be away for more than a day.
Kingrex
Well-known member
Ralph has said to leave his class D amp on 24/7.
Randy Myers
Well-known member
Sure, Class D has always advised leaving them on. Class A/B is usually ok to leave on also. Tubes and a Class A not so much for a variety of reasons.
Bones13
Active member
I have used class A solid state in the past, and could easily tell the difference in sound after the hour warm up. I was living in Houston, so they got turned off when not in use.
I cannot tell a difference, over an hour, with my class D amps.
I’m going to leave the burn in topic alone.
I cannot tell a difference, over an hour, with my class D amps.
I’m going to leave the burn in topic alone.
Randy Myers
Well-known member
Yea, the Class A amps I have had definitely improved after some time. I think the tubes did also. I did not really notice a difference with the Class Ds after any kind of warm up. My McIntosh I notice very little difference after some warmup time. There was definitely a break-in improvement though.
Interestingly enough, Ray Leung of Von Gaylord didn’t even put a power switch on the front panel of my LAD-L2 preamp. When I asked him about it, he told me that repetitive inrush current was as detrimental to the tubes as leaving it on. Either way, the tubes have to be replaced every 5 years.
I don’t personally have the technical chops to question his statement, although I guess that it’s also possible that he deliberately runs the 6SN7 tubes on the easy side.
RepublicOfTexas69
Member
Pass Labs
- Pure Class A Amplifiers: If you have a true Class A model (like the XA or Aleph series), leaving them on 24/7 consumes significant electricity (often drawing hundreds of watts at idle) and generates intense heat. This continuous stress can unnecessarily dry out internal capacitors and shorten their operational lifespan. [1, 2, 3]
- Standby Mode: For models featuring a front-panel standby switch (such as the INT-30A), use it . Standby mode keeps the critical input and voltage gain stages active while shutting down the output stage to reduce heat and power draw. [1, 2]
I have a pair of Ralph's Class D monos and they are turned off when not in use. Unfortunately no 12V trigger, but I have an alternative way to turn them off from my listening position. I don't believe there is any delay in getting them working at best sound quality when first turned on. This is another advantage of Class D - they don't need "warming up" as they run cold compared with most other technologies. However if you prefer to leave them on 24/7 your electicity bill won't be huge, but the life expectancy will be reduced somewhat I suspect - 20 years instead of 25 perhap!
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Mr Peabody
Well-known member
That is interesting some tube gear is alright to leave on. Maybe just low current. I had an Audio Note DAC the manual said alright to leave on all the time. It did have a power switch if you chose to turn it off at some point. I have a headphone amp with a tube that was alright to leave plugged in, no power switch. I don't use it much so go ahead and unplug that.
I've had solid state with no power switch, Pass Labs preamp and my former AcousTech phono stage.
RepublicOfTexas69
Member
I can see this being the case in a Pre-Amp
Kingrex
Well-known member
Agree. I could leave mine on. I have never changed the tubes and they are going on 7 ot 8 years. When I do swap them, I hear nothing. And its a $40 tube. So who cares.
atmasphere
Active member
As best we can tell, they do.
I don't think its wire; I think its the power supply. The following comes from an engineer to whom I spoke with about 35 years ago who worked with Cornell Dublier: At the factory, electrolytic filter capacitors are 'formed' to a specific Voltage- that of their rating. When they are installed in an actual circuit, they have a different Voltage applied to them which is something less than the rating. The caps have to re-form to that new Voltage. There seems to be a temperature element, which is the higher the temperature the faster they form up.
Class D amps run pretty cool so it might take longer than in a class AB solid state amp, although I suspect not by much.
When the caps are not fully formed they are less effective at their job, which is bypass of the power supply. On this account the supply is going to have more noise which can intermodulate with some portions of the amplifier circuit. The change in noise is slight but it is measurable.
Actually filter caps like having a charge on them- I would not expect a shorter life. As far as the life expectancy, we expect about 30-35 years since we are using 105 degree Nichicon filter capacitors that are running stone cold. The electrolytics in any amplifier will be the thing that needs service first, assuming everything else is engineered correctly.