They do, it is called stand-by. Some gear has it, some doesn't.
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4est-Standby modes are great, I was thinking of something that allows a person to keep the gear off for longer periods of time to either keep hours off their tubes or to save electricity if you have SS gear.
Cyclonicman-my pre also has a warm up cycle for 45 seconds before you can un-mute it. However, like yours it takes atleast a half hour to sound better.
The heat is a byproduct of the electrical current flowing through the stuff. It is waste and just needs to be gotten rid of.
I would say in analogy is like trying to say wearing a heated blanket is (in the same vein) the equivalent of doing warm up exercises.
Obviously the heated blanket is NOT a substitue for the warm up exercises. Both warm one up, but the exercise makes one ready to be active, where the other just makes one warm.
Just so, the external heating of electronic equipment is not really effective.
The ONLY use would be either a standby which keeps some current flowing all the time, or just leaving the item on.
Just so, the external heating of electronic equipment is not really effective.
I have a feeling I'm going to regret asking, but what do you base that on? Experience, some research you've read about, or just a guess? So you are saying an electronic component will behave differently if heated to the same temp if done externally rather than by dropping some voltage?
Your analogy doesn't hold water. Pouring hot water on your car is a terrible analogy.. A better one would be if you store your car in a heated garage so it is heated all the way through, not just on the surface. In that case it would definitely make a difference, just like raising the internal temperature of an electronic component no matter how it is done will make a difference.
This is done all of the time in precision test equipment. Temperature sensitive components that would affect the precision of the instrument if their temperature was allowed to drift, for instance the components that determine the frequency of a precision oscillator, are kept in little "ovens" inside the device where their temperature is precisely controlled. They are typically heated since it is usually easier to keep something warmer than the ambient temperature than it is to keep it cooler.
Since all Elizabeth can do is claim "you missed my point" and can't offer any reasonable explanation of why heating something up externally or internally will make a difference, I'll consider the case closed.
You guys kill me. All of you are posing to be so
knowledgeable about audio and not one of you could point him
in the right direction for the right component for his
situation. Amp warmers and preamp warmers are readily
available if you know what hi-fi shops to visit. They are
very expensive though. I run monoblocs, so I use four of
them. I do have an extra one for my tube cd player, but I
found out that it wasn't really necessary. I paid $2700 for
each tube amp warmer. I will sell my extra one for $1800
and guarantee it for one year. My solid state amp warmers
cost $2300. I will sell it for $1500. Lowballers will be
I'm surprised that Elizabeth gave up. Or maybe not, judging by some of the other comments. So let's examine this issue from the ground up.
When we say that a piece of (tube) gear needs to "warm up", what are we specifically referring to? Does the audio quality change because the case is warm? No. The knobs, wiring, lamps and switches? No. The PCB, if present? No. The transformers? No, not so much. The tubes? Aha! Now we are getting somewhere.
So why does the sound change when a tube heats? To keep it simple and avoid big words like anode and cathode, let's just say that a physical change occurs between the tube's internal elements. A tube does not operate efficiently until all elements reach the optimal operating temperature. While heat is required for the tube to operate, too much heat will destroy the tube. In fact, one of the reasons that power tubes need to be biased is to compensate for the heat potential between the an... never mind.
So why can't we just heat the tube with an external heat source like a heat gun or a heated blanket? Because "tubes" are vacuum tubes - the glass envelope encases the internal elements in a vacuum. No gas (atmosphere), no heat transfer can occur from OUTSIDE the envelope. See what you can learn when you don't sleep through High School physics class?
I wanna buy some tube warmer blankets. At the $1,800 price that is a real bargain.
I can see why precision testing electronics need to be kept at controlled temps. Just like a really cold engine ccan be easier to start if it is prewarmed.
Still it doesn't stablize the electronic circuits as far as stuff like the caps forming..
So I guess we can agree to differ.
But those tube warming blankets.. Mmmmm i need some.
The question WAS NOT asked, solely concerning TUBED equipment. In fact: the thread originator asked if he should switch to SS gear, so he could leave it ON all the time(and kept at temp). The atomic, or molecular, activities of EVERY circuit component(passive/active/connective), WILL be affected by temperature(and thus- the way they pass a signal). It's NOT Rocket Science, and ANYONE with a BASIC understanding of electronics/electricity SHOULD understand: (http://hyperphysics.phy-astr.gsu.edu/hbase/electric/restmp.html). NOT that resistance change is the whole story, but- it IS a major contributing factor in electronics morphing with temperature and/or warm up time(as Ms E connoted; Dielectric Absorption is a player as well).
Herman, I was trying to make a point, which my guess is that you understood exactly what I was trying to say even if it wasn't the best analogy. Foeget the analogies, why don't you enlighten all of us on this post. Personally, unless you live in a frigid area, this all seems extravagant and probably pointless for the type of equipment that is being discussed. You manage to criticize but offer valid answers only for temperature sensitive gear which is not what the original post was about.
The original question was
why don't manufacturers add heating elements to equipment to bring it too optimal temperature quicker.
It is ridiculous to think that externally heating a component won't do just that... "bring it to optimal temperature quicker." It matters not whether you think it is extravagant, that was not the original question.
As to the poster who pointed out that his garage won't heat an engine to operating temp.. same answer. Of course it won't, but an engine starting when it is room temp will certainly start easier and be ready drive more quickly than one that is freezing cold. Keeping it in a warm garage will "bring it to optimal temperature quicker."
As to the theory that tubes can't be warmed because they are in a vacuum, well, I'm sorry but that whole post simply makes no sense. If that were true then they would remain cool to the touch when operating. If heat can't get in then it can't get out. The simple truth is that everything inside is physically connected to everything outside through the base. The entire tube, inside and out, will eventually reach the same temp whether heated from within or from outside. Even if there wasn't a physical connection there is radiant heat which does travel through a vacuum as proven by the fact that we are warmed by the sun. Also, bias has nothing to do with "heat potential" between electrodes, in fact, there is no such thing as "heat potential" in a tube. Bias is used to establish the proper operating point for the tube. Too little bias and you increase distortion, too much can also lead to distortion and can overheat the tube.
Thank you everyone for the input.
I'm with you Herman, that some sort of heating would have a positive effect on the warm up process. I completely agree with all the posters that warm up is the only way to get the gear to sound it's best, my intent was to get a few opinions on "speeding" that process up with some sort of external/internal heating. It is my opinion that if a part becomes heated by normal operation during playback, then prematurely heating that part up to at or near operating temperature would result in quicker warm up times and shorter "cold sound" periods. My listening habits have changed and have become more sporadic and shorter in length. I have many nights where I plan to listen, I turn the gear on hours ahead and then not get a chance to listen. Therefore wasting electricity and putting hours on my NOS tubes. If I could get warmed up sound in about 15 minutes I would be a happy audiophile.
Herman, thanks for helping me to win a bet with myself. When I wrote:
So why can't we just heat the tube with an external heat source like a heat gun or a heated blanket? Because "tubes" are vacuum tubes - the glass envelope encases the internal elements in a vacuum. No gas (atmosphere), no heat transfer can occur from OUTSIDE the envelope. See what you can learn when you don't sleep through High School physics class?I just knew that you were going to reply the way that you did. OK, you caught me. I am guilty of a gross oversimplification.
The fact is that the glass heats up when a tube is powered because of radiant heat. But it's an inefficient process, and radiant heating from a high temperature source in close proximity is a very different process than "warming" from a low temperature source from several inches away. Do you possibly believe that you can pre-heat a tube to anywhere remotely close to operating temperature? Actually, that is done (sort of) for certain types of specialized lab gear and of course cold cathode tubes, which operate at a much lower temperature. But it wastes a lot of energy and can't be done except in controlled conditions.
And regarding your last statement that there is no such thing as heat potential in a tube. Really? So you believe that the anode and cathode in a typical vacuum tube are EXACTLY the same temperature? Planck's Constant indicates otherwise. So between your opinion and Max Planck, I'll take Max.
"The entire tube, inside and out, will eventually reach the same temp whether heated from within or from outside."
From that unimpeachable source, Wikipedia:
"Vacuum tubes require a large temperature difference between the hot cathode and the cold anode. Because of this, vacuum tubes are inherently power-inefficient; enclosing the tube within a heat-retaining envelope of insulation would allow the entire tube to reach the same temperature, resulting in electron emission from the anode that would counter the normal one-way current. Because the tube requires a vacuum to operate, convection cooling of the anode is not generally possible unless the anode forms a part of the vacuum envelope (in which case the cooling is by conduction through the anode material and then convection outside the vacuum envelope). Thus anode cooling occurs in most tubes through black-body radiation and conduction of heat to the outer glass envelope via the anode mounting frame. Cold cathode tubes do not rely on thermionic emission at the cathode and usually have some form of gas discharge as the operating principle; such tubes are used for lighting (neon lights and neon glow lamps) or as voltage regulators."
Do you possibly believe that you can pre-heat a tube to anywhere remotely close to operating temperature?
uh, did I ever say that?
And regarding your last statement that there is no such thing as heat potential in a tube. Really?
Despite referencing several textbooks as well as the web I find no mention of the phrase "heat potential" when it comes to vacuum tubes.. I make no apologies if I misinterpreted what you meant when you used unconventional terminology.
So you believe that the anode and cathode in a typical vacuum tube are EXACTLY the same temperature?
uh, did I ever say that?
Granted, the cathode is generally heated to increase electron emission. That in no way negates the fact that keeping the tube warm when it is not in use will decrease warm up time.
You all can ignore what the original poster asked and try to nit pick responses, but the fact remains... if it starts out at a warmer temperature it will reach it's operating temperature more quickly. That is crux of the debate, double speak and patting yourself on the back for clever responses "I just knew that you were going to reply the way that you did" doesn't preclude the fact that any of you who dismissed the reality that preheating the equipment has a positive effect were wrong.
"decrease warm up time" Well are we taking "How long a pre/amp take to sound it's BEST?" or how long it takes to be at operating temperature?
"I" thought we were taking about some slick way (pre heating with external heat) of making the waiting period (til the pre/amp whatever) for optimum sound (which is NOT just until the damn thing is warm). Now my prior amp (Forte 4a) took at LEAST an hour of being on to sound 'better' and nearly a whole day to sound great. Now hat amp was fully 'warmed up' in twenty minutes (far into class"A" operation) but no way did it sound great until it was on a whole day!!!
So i am sort of confused about some saying yeaah, external heat caould do it... no way IMO. Yes it could be 'warmed up' and 'at optimum operating temp' but NOT optimum sound quality from a external heat source.
Anybody care to clarify better?
To clarify IMO a "warmed up" component is when it sounds best, not that it is warm to the touch etc. As we all know those are very different when it comes to the sound of said component. I want to expedite the time it takes from off to sounding like bliss. Now when I say OFF I mean current isn't passing through the amp/pre amp circuitry, and sounding like bliss means it sounds like it would if it were left on all day everyday.
I think warmth is the result of the equipment being on, not
the sole cause of it sounding better, I think there is
something else going on besides heat (though operating
temperature is part of it - perhaps necessary, but not
sufficient on its own), along the lines that
Elizabeth suggests, and heat is a byproduct of that process,
and different than a mechanical engine, though a mechanical
engine may not be that different than heating up a cartridge
to "loosen" its suspension with an external
heater, versus the slower process of playing and warming up
the suspension assembly with motion (friction).
So i am sort of confused about some saying yeaah, external heat caould do it..
I see why you are confused... because nobody ever said that. Nobody ever said that external heat could keep a component at its optimum operating point.
The question was, would keeping the equipment warm speed up the process of being fully warmed up.. If you look at an extreme example it might help to understand the concept.
Take two identical amplifiers. Store one in a deep freeze and the other under an electric blanket. Take them both out and turn them on. Which one will reach the optimal operating point more quickly?
I am a little confused. I live in NY and I have to say that my tubed gear takes the same amount of time to warm up in the summer as the winter. In other words, if I wanted my gear to warm up faster, I would need these warm up blankets in the summer as well. The extreme example is easy to understand, but, let's face it, how cold can it possibly be in one's house. There is no deep freeze unless you're listening to music outside. Anyway, the extra time to warm up the gear keeps the house a little warmer in the winter.
I live in NY and I have to say that my tubed gear takes the same amount of time to warm up in the summer as the winter.
I assume you have some sort of HVAC system in your home that keeps the temperature in your home in a relatively narrow range winter and summer; i.e. you heat your home in the winter and cool it in the summer? If so then it should take about the same amount of time summer and winter.