Warm Up SS Amp
Apr 8, 2010 at 1:02 AM Thread Starter Post #1 of 22

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Many people believe you must warm up a tube amp before you get the best sound quality. What about solid state amps? Should I turn on my solid state amp early when I know I am going to use it later in the evening? Or is a solid state amp more like a TV that only requires a brief warm up? Thanks in advance for your opinion.
 
Apr 8, 2010 at 1:23 AM Post #2 of 22
Well my SS amp does not have an on/off switch as it is designed to be on permanently for "optimal electrical and thermal operating conditions".

The manual also states that:
Quote:

Upon first power-on... it is recommended that you wait for about one hour before use.


 
Apr 8, 2010 at 1:42 AM Post #3 of 22
Try Both, ON for at least 1 wk.......then ON when you go to listen then turn it off ! Now can you hear a difference????? Also who designed it? Is it Single Ended, if so "IT" might get to hot to leave unattended. This Is only MO.....
 
Apr 8, 2010 at 6:12 AM Post #4 of 22
No. Just turn it on when you intend to use it and turn it off when you're done. The same applies for tube amps.

Head over to Mouser or Digikey and check out the data sheets for resistors, caps, chips. You should find a MTBF (mean time before failure) stat usually listed in hours. That's how long a component is expected to last before it fails.

So, how long do you want your components to last before they die? The longer you leave an amp on the more hours are on the clock.

Not all failures are spectacular showers of sparks or flames. Failure also means when a 100 Ohm resistor turns into a 500 Ohm resistor. The amp might still work, but its parts will be out of spec.

I suppose you could call that "burn in," but I see them as parts that need to be replaced to keep the circuit operating as the designer intended.
 
Apr 8, 2010 at 7:19 AM Post #5 of 22
Tubes contain specific heaters; they are fundamental to their operation. Most tubes reach basic operating temperature in less than a minute, but seem to take a few minutes to fully stabilise. I echo Uncle Erik and turn it on when I need it, and it heats while I am musing over my musical choices.

Most SS amps are class A/B and (as far as I know) are not likely to benefit from any form of warm up. SS class A amps usually need a few mins to reach stable operating temperature, but will still be fully useable from cold turn-on.
 
Apr 8, 2010 at 7:55 AM Post #6 of 22
If you guys don't mind me asking, when I first got my earmax pro (and before i got some sense in me) I would turn it on and sometimes leave it for a long time,sometimes even for hours, before start listening... I don't do this anymore but I would like to know if there is a way to check if one of the amp components has failed? the amp seem to work fine and it sounds good, but like erik said...I can even know if one of the resistors changed its spec'.
 
Apr 8, 2010 at 9:00 AM Post #7 of 22
Quote:

Originally Posted by plonter /img/forum/go_quote.gif
I would like to know if there is a way to check if one of the amp components has failed?
... can [ I ] even know if one of the resistors changed its spec'.



Most failures would be indicated by at least one of the following:

It overheats and smells
It overheats and smokes
It makes sparks inside the tube
It makes unusual noises at the output
It just 'sounds wrong'
It does not work

Otherwise it is very likely to be OK!

smily_headphones1.gif
 
Apr 8, 2010 at 9:07 AM Post #8 of 22
Quote:

Originally Posted by Leny /img/forum/go_quote.gif
Most failures would be indicated by at least one of the following:

It overheats and smells
It overheats and smokes
It makes sparks inside the tube
It makes unusual noises at the output
It just 'sounds wrong'
It does not work

Otherwise it is very likely to be OK!

smily_headphones1.gif



thanks a lot, I experienced non of these issues so I guess my amp is fine.
 
Apr 8, 2010 at 9:25 AM Post #9 of 22
AFAIK, it depends on two things:

1. Whether the amp heats up significantly if it has been switched on for some time (especially class A designs)
2. Whether the amp has been calibrated by the designer to function best at the temperature it reaches after warm-up

My (completely subjective) experience with the Corda Opera is that it takes about 20 minutes 'warm-up' to sound its best.
 
Apr 8, 2010 at 2:05 PM Post #10 of 22
Quote:

Originally Posted by Drosera /img/forum/go_quote.gif
AFAIK, it dHeadphone Amps (full-size) Discussion of desktop headphone amps.
Headphone Amps (full-size) Discussion of desktop headphone amps.
epends on two things:

1. Whether the amp heats up significantly if it has been switched on for some time (especially class A designs)
2. Whether the amp has been calibrated by the designer to function best at the temperature it reaches after warm-up

My (completely subjective) experience with the Corda Opera is that it takes about 20 minutes 'warm-up' to sound its best.



The Beta22 technically takes about 20-30 minutes to stabilize. Temperature definitely makes a Measurable difference (audible i have yet to find out the degree). The JFETs seem highly sensitive to temperature and they take the longest to stabilize they are about 25% off their default reading when cold - their current increases with temp which makes them run hotter. The Mosfets probably take 15 minutes and they run at around 150 degrees with the average recommended bias.
 
Apr 8, 2010 at 2:10 PM Post #11 of 22
I've found over many years and many amps that class A/B solid state don't benefit from a long warm-up; about 30 minutes and they're pretty much optimal. Class A amps, however, in my experience, sound best when left on 24/7 and are best after 24 hours or longer. That said, I have not really tested this out with headphone amps (currently using a class A headphone amp) - these observations are with speaker amps.
 
Apr 8, 2010 at 2:13 PM Post #12 of 22
Please forgive me, but what is the difference between Class A and Class B, solid state. If my GLite + DPS is Class A material, does this mean that I can leave it on all of the time? Hmmm...
 
Apr 8, 2010 at 3:14 PM Post #13 of 22
I leave my amp on throughout the day and sometimes over the weekend. I've been doing this for three years with no sign of damage. I agree with what UE says about wear but every time you cycle the on/off you do damage by heating and cooling physical structures. Some components are better left to operating temperature/voltage than cycling.

Best to try things for your self. Leaving a component on (even in standby) is pretty common practice so experiment. Personally, I think my tube gear sounds better when left on during my listening sessions as opposed to turning it on and off several times a day.

IMO
 
Apr 9, 2010 at 10:55 AM Post #14 of 22
I would also like to leave my amp running sometimes,but I am afraid from the electricity stopping, because it can happen quiet often in my area,especially in the winter time. that's the main reason that I don't leave it on when I leave home.
 
Apr 9, 2010 at 11:45 AM Post #15 of 22
It's my subjective observation that SS amps (particularly cool running, non-class A types), benefit from days of warm up. As jinhh said, some models don't even have an on/off switch. Naim models were well known for requiring days of warm up to sound their best.

Also, my Stax 007t energiser (hybrid) sounds better after 1 hour than it does after 10 minutes, and (surprised me) better still after 1 day. This defies simple logic and I can't explain why it should be, since it is at full temerature within an hour or so.

However, if anyone can't tell the difference in sound quality in their own situation, then they should simply not worry about it and leave it off or on as most convenient to them.

Regarding longevity, it is often reported that regularly switching any electrical component on/off will reduce it's life compared to leaving it on all the time. Famously repeated in IT departments - if anyone tried switching off unused computer servers, say at the weekend, they would probably get the sack.

As plonter says, there are other factors involved - like supply reliability. So you need to take all these things into account. Personally, I would never leave on a class A power amp indefinitely - bad for the electricity bills, the planet and possibly a fire hazard. But I sometimes leave my Stax on over the weekend and I would only switch off my CDP when I'm away for several days.
 

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