After reading the very interesting post on speaker wire I thought I throw out something about warming up your system and never turning it off. If you leave your pre-amp and amplifiers on 24/7 365 your audio sound will be better. Significantly better. A friend of mine is an EE and a audio/videophile and he told me to try this and see for myself. Try this test if your equipment is high end. Leave your pre-amp and amps on for a full seven days, play a good CD with some decent music on it and play a certain cut over and over so the sound is well in your head. Then turn the equipment off and come back an hour later and turn everything back on and play the same cut on the CD and you will hear a very inferior sound compared to the sound you heard prior to turning the equipment off. I know people who never turn their equipment off. I don't follow this rule but I do turn my equipment on several hours ahead of listening.
I know people who never turn their equipment off. I don't follow this rule but I do turn my equipment on several hours ahead of listening.
I am Guilty!
The main reason I leave it on is because I will forget to turn it on if I turn it off and it takes about 4 hours for everything to get back to where it was. Recommended for the hardcore only. This can be tough on the equipment and your electric bill depending on what kind of amps you have.
I leave my system on all the time, in fact my Pass Lab preamp does not even have an on/off switch. Back when I was using tube amps, I would turn them off when I wasn't listening...darn tubes are so expensive.
Richard, if you read this, sonics aside, isn't there less wear on a solid state if you run it 24/7 rather than turning it on and off?
It is true that most electronic components go through a brief period of chaos when turned off and on, when the voltages and such arent balanced, its a prime time for things to break and components to wear, however... you have to balance that against the cost of the electricity, and the type of equipment.
If you turn your equipment off religously between uses, you can save a couple hundred bucks in electricity over the course of its lifetime. And if none of that equipement breaks due to Power-on issues, then your ahead of the game, economically speaking. And there IS A very good chance that nothing will break, especially with transitor-based stuff. And, if something breaks after 4 years, is that always a bad thing? Electronics do tend to improve over time, so replacing an item that breaks can bring joy as well.
Also, if your equipment is stuck in a poorly cooled enterainment center, it could wear on your equipment more to leave it on. Also, you have to factor in other economic issues, like in the wintertime, Im less concerned with turning my equipment off at night, because its a heat source. In the summertime, I turn it off quickly, because its a heat source.
Then theres the subject of the western world using way too much energy and contributing to global warming, which i will merely mention.
Concerning wear and tear there are certainly good theories based in logic for leaving the stuff on. On the other hand I have not found it detrimental to solid state products to cycle the power in all these years. The engineer that I work with has stated that it is good to cycle the power now and then for the main caps so they can fully discharge and recharge. I have forgotten all the reasons behind it.
Most modern amps have relays and time delays to allow all of the caps and power supplies to be fully functional and charged before signal is allowed to the speakers so there is no "chaos" or thump. Most modern solid state amps, although tolerable of being left on wil tend to run more "class A" which means they are drawing current and generating heat. So there is a risk/benefit. wearing out the on/off switch and maybe popping a fuse every 5-10 years or paying a ton of dough on your electric bill and also risking heat damage, resistors in particular, like to change their values when exposed to heat over long periods of time. I have never heard of turning off and on an amp to "recharge the caps". The caps perform 2 main functions in an amp: 1. they act as filters to smooth out the ripple from the power supply and 2. Act as a resevoir of extra current to handle peaks in the audio output. (there are other functions for caps as well, coupling, rf traps, oscillator circuits, etc. but I'm refering to the big boys). I have a Sencore capacitor analyzer that allows me to "reform" dried out caps. If you own vintage gear run it often to keep it healthy and the caps from drying out. For safety purposes most large filter caps have bleeder resistors to slowly discharge them when switched off (otherwise there would be a lot of dead techs). The caps will always charge to the voltage levels provided by the power supply. Solid state amps can be up there in the +/- 70V or higher range.
Tube amps can have 500+ volts or more and can be quite dangerous if you don't know what you are doing. You can easily get killed working on a tube amp.
Tube amps are another matter. If you leave them on all of the time the "getter" will dissipate and lose many of its "free" electrons and the tubes will wear out or lose their "mu" or gain. Anyone who has purchased tubes lately will know how costly that is and unless you can find NOS you will be buying somewhat inferior Russian or Chinese made tubes since there are none in commercial production in the US anymore. The filament on tubes typically heats up slowly and they last a very long time. My 1964 Hammond B3 still has all of its original tubes with the exception of the 122 Leslie which I replaced the 6550's with a matched pair (but the pre and driver tubes are original). I had a 1959 Hammond C3 and it had all of its original tubes as well.
The AC mains voltages are equally dangerous on both types of amps.
If I am ever in San Fran I would love to get together with you!
I have never heard of turning off and on an amp to "recharge the caps".
This is only a concern if you leave it on all the time. It had something to do with them losing their efficiency over long periods of time and one should turn off their amp for like 10-15 minutes so they fully discharge and then turn it back on. The in rush current snaps them back to life. Something about them getting a memory so to speak and holding back on their full current delivery when asked for it; unable to dump the charge as quickly. This is audiophile speak related purely to how something sounds and has no bearing on everyday electronics...
If your friend is a real EE he would have a scientific explanation, not some mumbo jumbo that is impossible to verify.
Non-Tube sytems get rectified in milli-seconds--and in a worst case a few seconds.
While tubes take longer, who wants to shorten the life of expensive tubes by keeping them on for long periods of time without listening to music? As your EE must know, heat is the enemy of electronics.
I would only trust such an experiment in an ABX double blind test. Your ears and mind are great at being fooled.
It seems the deal is that the currents in the transformers are not stable until the core is thermally stable. This is also relevant in some of the various other stages of the amplifiers. Also connections become more (or sometimes less) adequate if lightly loaded over time. Anyone who has removed spade lugs from DC terminals knows what I am talking about. I have also heard about Caps growing crystals in them which reduce the Max Voltage and current flow of the devices. Like memory in batteries. But I was under the impression that you just "get" to replace Caps every 10 to 20 years in most audio equipment. Oh yeah and heat is bad for Caps.
Most people I know leave their low voltage devices on all of the time. Pre amps, players etc. and just switch the main amps on and off. Of course they do sound better when they are fully warmed up which can take quite awhile. I'll admit that I notice this sort of behavior much less when the devices have extremely stiff power supplies.
I turn my HT system off because it is in a room that is subject to excess heat and I don't want the A/C to have to work any harder than necessary. I never shut off anything in my Audio Only system. But it is in the living room and the amps are class A/B and don't pump out tons of heat unless signal is running through them.
AHA - so that's why they have temperature ratings on capacitors (being a little facetious here)! The new caps will last a lot longer than the old designs and they are a lot smaller. In the past 20 years they have made major technological improvements in capacitor technology (dielectrics, insulators, etc.). I rarely see bad caps in modern equipment (more often mismarked, wrong value or omitted).
I turn all of my gear off when I am not using it. My Denon sounds fantastic from the moment the relays turn on the speaker circuits. I leave the self powered sub on but it it supposed to go into low power mode when there is no signal applied.
I have honestly never heard of transformers having to heat up for optimum performance either. I have have some pretty good analytical gear here - spectrum , real time and distortion analzers - and good stuff too, Tektronix, etc.
I can always be wrong - show me a link to the science.
Anyone remember the late 60's / early 70's tube TV sets that when turned off had a lower voltage running thru the tubes ? Think it was called instant on. Claim was it would prolong tube life.
My office UPS logs tell me my electric company delivers a power source that includes
voltage dips and spikes due to switch yard changes, load, storms, or the new 16 year old driver hitting a pole on my street. Even with a UPS on my audio system I cringe when I think what these artifacts do to our equipment over the short and long term.
Yes I remember that, and in a television servicing class I took back in the 70's they said it was a lie. People simply just wanted their sets to come on faster. Tubes rarely ever have filament failures.
Part of the reason they have such large caps in the power supply sections is to deal with voltage fluctuations and More and more I see surge suppressors built right into the power supply circuits. Almost all of the voltage in modern amps and TV's is regulated anyway. Sometimes the power supplies for the power amp IC's or amp output transistors is unregulated.
On another unrelated note the standard line voltage used to be 115VAC. By the raising it to as much as 123VAC they can reduce the amount of current that the transmission lines (the ones on the top of the power poles) carry. Many power supplies these days are so universal they will function nicely at 50-60~ and at voltages from 100-240V.
The main danger of someone hitting a tree is the 5Kv line breaking and hitting the 240 lines on the lower part of the power pole. There's not much suppression equipment can do to protect against an an extended surge like that into your mains.
Yes I remember that, and in a television servicing class I took back in the 70's they said it was a lie.
The theory is that the heaters would not have the radical physical changes that must occur when going from cold to hot. By leaving the heater on halfway it kept the temp up and it increased the life of the heater as well minimize the risk of shedding surface material which can then short out elements of the electron gun(s). Bear in mind the heater is just one element of a complex cathode ray tube and this circuit had no bearing on phosphor wear...
Sure, this could be applied to any tube circuit but picture tubes were not your $2-5 6GH8's or 12AX7's that pop in and out...
Another on this note is the FED requested or passed a law to have this circuit removed from new product designs years later during the 70's energy crisis lest the country waste it's resources on TVs...
