Breaking in equipment...ie Amps

[highfigh]

I think what he is getting at is....don't bring in equipment from the COLD and immediately plug it in and turn it on. Just be sure it's at room temp first.

Yeah, in general, I think break-in on electronics is BS.

I do think there is a bit of break-in on speakers.....but honestly the data that I have seen absolutely suggests otherwise.

Now, tube gear and breaking it in might be a different animal.

Ever look at the temperature range for this stuff? It's often stated as "0°F-140°F". I have an old Sony STR-5800 receiver from the late-'70s in my garage. I'm in the Milwaukee area and when I'm in the garage for any length of time, the stereo is on- any time of year. It's not in an enclosure, covered or protected in any way.

 

[slipperybidness]

Yeah, but this is still a bit of a different scenario. Your receiver is still in the cold when you switch it on.

The point on this item-- If you have gear outside in the cold, then you bring the gear into the warm house, the warm air in the house has more moisture in it (higher humidity) than the air outside. You now have a cold hunk of metal and higher humidity, so the water in the warm air condenses onto the metal inside the electronics.

Then, you plug it in, then you fry your gear due to the moisture that condensed.

So, when bringing gear inside the home from outside where it is cold, you really want to let the temp on the electronics to equalize with the temp in the room before you plug it in.

In other words, it's the SUDDEN CHANGE IN TEMP that is the problem, not the ABSOLUTE temp.

I learned this from you Northerners. Down here in TX, it's rarely much of a concern.

 

[highfigh]

Yeah, but this is still a bit of a different scenario. Your receiver is still in the cold when you switch it on.

The point on this item-- If you have gear outside in the cold, then you bring the gear into the warm house, the warm air in the house has more moisture in it (higher humidity) than the air outside. You now have a cold hunk of metal and higher humidity, so the water in the warm air condenses onto the metal inside the electronics.

Then, you plug it in, then you fry your gear due to the moisture that condensed.

So, when bringing gear inside the home from outside where it is cold, you really want to let the temp on the electronics to equalize with the temp in the room before you plug it in.

In other words, it's the SUDDEN CHANGE IN TEMP that is the problem, not the ABSOLUTE temp.

I learned this from you Northerners. Down here in TX, it's rarely much of a concern.

Have you been to Wisconsin in Winter? When the outside temperature is low and the heat is on for long periods, the humidity can drop below 15% if there's nothing adding moisture. One of my acoustic guitars cracked in two places last year and that's the first time ever, in the 35 years I had owned it. When the RH is that low, someone wearing glasses can walk in and they won't fog.

You want to see moisture, we get warm, humid days during some Winters that show up when they feel like it and it rolls in fast! It can go from cold to frost is a few minutes and anything exposed is going to be coated. I have looked at old car radios and it's a wonder they worked at all. No epoxy coating, nothing to protect from moisture.

All manuals address this but almost nobody reads them. Definitely best to let it acclimate.

 

[highfigh]

I had a pair of Phillips 6x9 coaxial speakers that used their AD-0163 textile dome tweeters, with ferro-fluid cooling. A friend who has worked with electronics and audio for longer than I have asked about them- "What do you do about the ferro-fluid in Winter, when it moves more slowly?" and I answered "I just crank it up 'till it clips. Warms 'em right up". IIRC, he dropped the phone.

 

[markw]

The point on this item-- If you have gear outside in the cold, then you bring the gear into the warm house, the warm air in the house has more moisture in it (higher humidity) than the air outside. You now have a cold hunk of metal and higher humidity, so the water in the warm air condenses onto the metal inside the electronics.
...
In other words, it's the SUDDEN CHANGE IN TEMP that is the problem, not the ABSOLUTE temp.

anyone that wears glasses experiences this when coming into a warm environment from a cold one. Their glasses fog up instantly.

 

[hankki]

Humidity, atmospheric pressure and temperature are connected and if you know two you can calculate the third. Dew point or 100% RH happens when temperature drops to the point when air can not hold the humidity anymore or you get fog on your glasses. So if you have really dry air inside your house you might not get fog on glasses.
I am from finland and is used to foggy glasses in the winter but I experienced the opposite when installing a machine in Schaumburg, IL and going out from the airconditioned building after rain and still 100 degrees outside.

 

[highfigh]

Humidity, atmospheric pressure and temperature are connected and if you know two you can calculate the third. Dew point or 100% RH happens when temperature drops to the point when air can not hold the humidity anymore or you get fog on your glasses. So if you have really dry air inside your house you might not get fog on glasses.
I am from finland and is used to foggy glasses in the winter but I experienced the opposite when installing a machine in Schaumburg, IL and going out from the airconditioned building after rain and still 100 degrees outside.

I tried to make the point about extremely dry air, but.....

You could have gone outside in Schaumburg with your cold glasses at 80 degrees and they would have fogged after rain with Relative Humidity less than 100%. Did you enjoy the 100 degrees after it rained? I'm not a fan of that kind of weather.

 

[hankki]

This thread is going OT. I don't like 100 deg in any way all above 80 is too much.

 

[Paul Scarpelli]

Most amplifiers, or at least output stages, are burned in at the factory, on "burn in racks." I worked for manufacturers for decades, and I was involved in product development in addition to sales and marketing. Amps are burned in so if they fail, they will fail before being shipped and sold. Components seem to fail early, and if they don't, they usually will last for many years. I have never witnessed a break-in period where an amplifier was transformed over 400 hours from a strident banshee to a smooth, natural sweetheart. It doesn't happen.

That said, playing a cold amplifier hard is a bad idea because the temperature difference between the inside and outside of some components (output transistors, for example) may be too great and cause microscopic cracks to develop. Play an amp at a moderate level for ten minutes before beating on it. Some amplifiers, as long as they're plugged in, draw a small amount of current in stand-by mode, keeping circuits ready but outputs muted. Recent RoHS requirements state that amplifiers can't draw much current at idle anymore. We used to let amps idle at 100 watts power consumption so they sounded good from the first note, and in retrospect, that was ridiculous. Amplifiers were often over-biased and they idled red hot. Heat over time kills amplifiers. Also, the violence of turning an amp on doesn't help it, either. I usually don't ever turn mine off; vintage McIntosh or super-modern Lyngdorf semi-digital. If I know I won't be playing any of my systems for a few days, then I shut them down.

If an amp has been outside in cold weather, let it sit inside for a day before even plugging it in. If you turn a system on, don't play the bejeezus out of it until semiconductors have been brought up to optimum temperature.

 

[TLS Guy]

All of the EL34 tubes are glowing, and it seemed like I was able to set the bias fine. I did give all the tubes a good wiggle and did swap the left/right output tubes. Still no dice. That's about all I have done for troubleshooting. I figure if I open it up, feed it a 1kHz sine wave, and start snooping around with my DMM and O-scope, then I should be able to root out the problem.

To be clear, this is a NEW ST-70 clone that I built from a kit (Bob Latino / Tubes for Hi-fi vendor). Bob is well known to be the best in the business when it comes to customer service and troubleshooting help. But, I haven't contacted him yet.

I'm not exactly hurting for amps! Pio AVR, Parasound 1206, Boxed Kit Amp Gobo, and working up a couple builds on LM3886 and LM4780 now too.

Feel free to critique my current work. Constructive criticism is always welcome, don't worry too much about hurting my feelings (assuming that it's fact based and objective comments).

http://forums.audioholics.com/forums/threads/new-chipamp-project-thread.92513/

Just use your signal generator and O scope and you will find it. Go stage to stage and then drill down where you find the signal stops.

I would bet you have a dry joint somewhere in the signal path. They often don't declare themselves immediately.