Doh, left system off all night

Today I've been really unhappy with the sound of my system. Bass is too bloated and treble is scratchy. I was racking my head trying to figure out what I changed.

Took me an hour to remember I left the system off for about 24 hours. Doh!

So many threads debating the benefit of leaving components powered up. You've provided some proof. Although every system is different and each component may need to be treated differently.
yup, that's what my system sounds like cold.  Over-accentuated highs and light bass.  Within 45 minutes or so, it really fills in the body and tightens up.
I don't leave my system on all the time, because I don't need to. However, it takes about 1.5 hours to come to life, and that's play time. There is an increase to the sound quality up to about 3 hours, but after that It's done.

I can also just turn it on and leave it on, but it still takes about another hour of play time to fully come to life that way.

The bummer, is when I forget to turn it on to start with!
I leave my SS high current amp on 24/7. After a cold start, it takes a couple hours to sound decent, but improves over the course of the day.
Tube pre is turned off and  I wait 20 minutes to listen, then SQ improves after an hour.
Interesting.  I really didn't end up liking it that much last night. Today it's certainly better.

Interestingly, my amps, Class D, stayed on during all of this, so whatever I'm hearing it's between the source and preamp.


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I have an all tube system and turn it on about an hour before a listening session, even doing this it still needs another 30 minutes to an hour of actual playing time to get up to speed.
Erik,  IMO, class D requires more time to reach optimal temperature.  I own both tube and solid state gear and it never takes more than couple of hours before I sit down to enjoy my system. 

Tube gear takes about half an hour to 45 minutes. Solid state amps sometimes take a few hours of playing music, sometimes a lot less. But once the amps are on and warmed up, they don’t need continuous music.  I usually leave them on 24/7 and don't have to worry about warm-up.

But the SS DAC!!! ughhh... That needs a few hours of music to warm up and continuous play to stay that way. I’m getting a new DAC so I’m not too worried about it.
Hi @lalitk

My amps were the one thing that have not been turned off in weeks. :)

The two components which were included a Mytek Brooklyn and Parasound P7.


Hi Bpoletti,

If I may, what DAC you are considering?  I own a Modwright Elyse and thinking about auditioning Aesthetix Pandora 'Eclipse' or AR DAC9.  

Erik, I find the same thing with my Class A amps. They continue to improve (logarithmically) for about 10 hours, but are listenable after one. Oddly enough, the SS preamp is pretty stable after 5 minutes.
My stuff never really turns off..keeps a trickle charge running...only powers down, so that it sounds wonderful as soon as I turn it on (Ayre)

I cannot disclose the DAC I will get because it will end up being somebody's prototype.  But the DAC I have been using is an out of production modified Douk.  There might have been others better, but not in my system.  

String...   nice feature.  My Herron amps don't draw much when just sitting in the man-cave at idle.  i just walk down stairs and turn on the preamp, phono stage and start the turntable spinning an hour or so before I go down to do any serious listening. 
Bpoletti....No problems.  Enjoy your new DAC! 
I was in the "always on" camp since the sound is best that way, but repairs and tube life issues made me reconsider. I turn on my tube amps and preamp an hour or so before playing, and turn them off at night. So they are on perhaps 6 hours a day, not 24.
I hear you, @o_holter

My listening style is too random, so I need my gear on all the time, meaning: No tubes for me!

Environmental Issues update: Based on recent data regarding Arctic warming (today in the NY times for example) and Greenland ice sheet melting, I’m pretty sure we’ve irreversibly lost the battle with climate change so hey…waste all the juice you can while there’s still some time on the clock. Leave it on…all of it…all the time.
We have lost the battle a long time ago, as the sun will eventually grow larger and consume the earth. There's just no stopping it.
o_holter - Tubes don't have the warm-up problems that ss does.  My experience is that tubes take a max of an hour or two to reach their envelope of best performance.  Solid state can take 10 times that long or longer.  So tubes can be MUCH more economical to get to good listening than solid state.
I have a Class A amplifier that draws on about 400 watts (Pass Labs). No doubt it sounds way better warmed up after an hour or two. That said, I turn it off before heading to bed and back on in the morning before heading out for work. It has a chance to warm up all day before I get home which is plenty. So the amp gets about 8 hours of downtime every day.

I sleep better knowing I’m being kinder to my electric bill and the environment. Con Edison in NYC charges 27 cents per kwh which is the highest electricity rate in the nation if I’m not mistaken. 400 that math! Yikes.
Yeah, my big mono Class A amps will heat you out of the room in summer, and then there is the cost of electricity - the equivalent of having a 1 kw space heater going whenever they are on.

Fortunately they take very little time to warm up.
Also the old debate... that one's system will sound better late at night (especially on weekend) after the power grid is freed up.

@erik_squires what amps are you running? I still think my amp is my weak link, but I like class D.. I think some proper higher end (than what I have) monoblocks is where I'd like to go. The w4s mAMP looks nice.
todd -
I'm using ICEPower ASP 250 based amps.

I had reported that my system reached its maximum SQ about 1.5 hours after turning it on, so why I don't leave it on. I need to retract that statement.

I accidentally left my system on all weekend when visiting our children out of town, and when we got back my knee-jerk was to shut it down, but instead played my new Ben Allison LP (Newvelle) which I had left on my TT. So, the last thing I listened to before spacing out my system.

The SQ improvement was big, so I wanted to let you know this even though my post was back in December.
I remember old carbureted engines that had a manual choke and had trouble starting on cold mornings. Amazing that they fixed this with modern technology.

Sad that some audio equipment should be still so poorly designed as to sound terrible until after an extended warm up. I have read that Class D is very difficult to do right and hard to build with reliable performance. A bit like Class AB is significantly more likely to have problems than Class A. Although Class AB is pretty good these days.
My rig is composed of items designed well enough so they sound great from morning start up, and since I don't necessarily listen closely before I've been up for a while I have no idea if the rig improves, but I don't care. I've, of course, come home after being out with the stuff turned off, but even then I generally do other things before listening. It's off all night, except for the "sleeping" REL subs as I prefer the electrons stay away from my gear when they're unsupervised as I can't trust pesky unsupervised electrons. Besides, my SEP tube amp deserves a break.

That is funny, good to know. ;)


Yeah, I worry about having too many devices on, but my 3 HT amps take up like 21 watts while on, so I feel like I"m saving my bill and the environment by sticking with Class D. :)


Yeah, and l'm in the same boat with not wanting to leave my tube amps on. So, more of an interesting discovery than a practical solution.

This issue has been discussed many time, but, it never hurts to revisit it.

I had an experience a few years ago.  In my system, I have Martin Logan Monolith III speakers.  I also use a Krell KBX electronic crossover that is configured with wave shaping circuitry for the speakers.  The KBX is solid state and doesn't have an on/off switch.  So it is typically always on, unless I unplug it.  Well, I noticed a burning smell.  barely noticeable at first, but it got to the point where I had to find out where this was coming from. 

It turns out that this KBX unit is definitely class A, totally discrete circuity and extremely well designed (circuit wise).  But, that sucker gets warm, and being left on, definitely didn't help.

I traced the problem, reversed engineered the schematic and repaired the unit.  But, I told myself that I would never leave electronics on all the time in the future. 

Not only do I not want my home burned to the ground when I get home from work, but It just didn't make sense to me to leave this equipment on when not in use.

So, I unplug the KBX after uses, turn off everything else.

I noticed that after about 30-45 minutes of warm up, my system sounds great.

I have solid state equipment and tubed equipment and no way on this planet will I leave the Audio Research REF 250 amps on all the time.  With about 2000 hours typical use on those very expensive tubes, that is a non starter.

The Audio Research Pre-amp, Phone stage and DAC also.

The Mark Levinson 23.5 amp that I use to power the woofers on my speakers gets warm also.  I recapped the unit a little while ago, when I decided to get it serviced.  But, being an Electronics Engineer, I know a little about heat and how it affects electronics. 

Other than my refrigerator, I really see no reason at all to leave equipment on when I'm not using it.

But, to each their own.  I learned my lesson with the crossover.  I guess I could install a power switch, but it is just as easy to get up and unplug the sucker.

Now that I'm thinking about it, my Transparent Audio Power conditioner is always on also.  Hmmmmmmmm.  need to think about unplugging that unit also.

It is starting to get a little old having to turn everything on and off.  Plug the KBX in first. Turn the pre-amp on, turn the phono stage on, turn the turntable power supply on, then go and turn each amp on.  Lots of walking around and bending.  I know.  It sounds silly and lazy complaining.  But, I guess it would really suck coming home to a house fire.

Just thinking.


Yeah, I only leave my class D amps on. Everything else gets shut off when I'm done. No way am I leaving my tube pre on all the time. That sucker gets hot! I can only imagine how toasty tube amps would get!