Safe to leave tube head by window?

[Stratocaster]

To keep it simple, I keep my amp just by my window, with the back of the head (which is open) facing the window. Is there anything wrong with a slight breeze getting on my amp? Sorry I might just be a little paranoid lol.

[ne1roc]

For a very accurate answer can you tell me your address along with a picture of the open window it is in front of. Also, time of day the house is empty would be helpful too! :smile:

Seriously though, probably the only thing to worry about is an unexpected heavy rain storm. I myself wouldn't keep the amp in front of an open window.

[Stratocaster]

For a very accurate answer can you tell me your address along with a picture of the open window it is in front of. Also, time of day the house is empty would be helpful too! :smile:

Seriously though, probably the only thing to worry about is an unexpected heavy rain storm. I myself wouldn't keep the amp in front of an open window.

*Looks at ne1rocs location*

*Looks at my location*

*:frown:*

LOL, but I'd be more worried about someone stealing an original Kramer Baretta (if I had one). You must keep that thing behind a glass case with it's own alarm system:eek:.

Thanks for the help fellow mississaugian!

[konasexone]

Tubes don't like steep temperature transients. In other words ,don't heat up your tubes and then cool them off real quick which is what might happen beside an open window. They get old real quick when subjected to hot-cold shifts. Let them cool off by themselves at room temp and don't move the amp until its cooled down.

[ne1roc]

Tubes don't like steep temperature transients. In other words ,don't heat up your tubes and then cool them off real quick which is what might happen beside an open window. They get old real quick when subjected to hot-cold shifts. Let them cool off by themselves at room temp and don't move the amp until its cooled down.

Not moving the amp until its cooled is pretty difficult when you gig.

[Ripper]

Not moving the amp until its cooled is pretty difficult when you gig.

especially outdoor gigs.

[Archer]

To keep it simple, I keep my amp just by my window, with the back of the head (which is open) facing the window. Is there anything wrong with a slight breeze getting on my amp? Sorry I might just be a little paranoid lol.


a breeze???



Good lord your amplifier may catch a cold and die!!!!!

Get it to a doctor.

[Archer]

Not moving the amp until its cooled is pretty difficult when you gig.


Pretty much impossible. I have never bothered following that rule and have not had an issue in years. Most other gigging players I know also regularly ignore the 'dont move until it is cold' rule too....no problems.

People think tube amps are WAY more fragile than they actually are.

[Ripper]

People think tube amps are WAY more fragile than they actually are.

+1 on that for sure. The only thing I do do is if the amp has been out in the cold, I will let it warm up to room temp before firing it up, but when I say cold I mean in the back of the van in the winter type of cold.

[Wild Bill]

+1 on that for sure. The only thing I do do is if the amp has been out in the cold, I will let it warm up to room temp before firing it up, but when I say cold I mean in the back of the van in the winter type of cold.

Back in the late 80's I worked for what was left of the old Canadian Westinghouse Tube Division. Twenty years before that it had been a big factory in Hamilton's west end, employing hundreds of people. By the time I got there it was just a handful of old folks, hoping the business would last until they retired.

By then they were no longer a manufacturer but rather just brokered tubes, buying from here and there and remarking them to put into Westinghouse boxes. I am forever grateful for the chance to benefit from all the years of experience and wisdom of those people as regards everything to do with tubes. It was sad that no effort was made to preserve any of that knowledge. It died with the retirees.

Anyhow, from what they taught me, tubes don't really notice much difference from ambient air temperatures. There is such a big difference between the temperature of a hot filament and a cold one that a few tens of Celsius degrees difference outside the glass is trivial. The glass is also thick enough and tempered that it isn't likely to shatter from the stress of going from hot to cold.

That being said, there are a couple of temperature things that ARE very important!

First off, the heater/filament is very tough when cold but kinda fragile when hot. Ever notice that you could knock over a lamp that was turned off and if the bulb didn't physically break it usually still worked ok. Knock it over when the lamp was turned on and the bulb burned out inside. That was because a hot filament breaks much easier.

So tubes can be shipped in parcels and survive just fine. Knock your amp over while playing a gig and odds are you'll lose a tube or two.

When an amp is turned off the heater/filaments in the tubes will drop at least 80% in temperature within a minute or two. They should no longer be fragile.

The other issue is ventilation. Tubes get hot and depend on the air to move heat away from the hot glass and out of the tube. Too many tubes in an amp without much air movement in the back builds up a lot of heat. This can dramatically cut tube life. It's not so bad in a Champ with only a couple of tubes but in a Twin, JCM800 or a lot of the new gain monsters it can be scary. Peavey Classic 50's and those Vox amps with a quad of EL84's tend to cook tubes.

It's not just tube emission life but also the excess heat with cooling spells that causes internal expansion and contraction of all the plates and grids and stuff inside the tube. This often makes the mechanical bracing go looser and things vibrate, causing microphonics and unpleasant noises.

Tubes LOVE fans! Power tubes for audio and radio transmitters usually had forced air blowers. Guitar amps can almost always benefit from even a small fan like those found in a computer power supply. I like to scrounge those 'cuz first, you can find old computers in garbage cans and second, they're 12 volt DC fans. Usually you can steal some AC voltage from the filament winding and rectify it with a filter cap of a couple of thousand microfarad at 16 volts or better. This will give you maybe 8-9 volts of DC under load to run the fan.

When you run a 12 volt DC fan under voltage it turns quieter and more slowly. You don't have to run a hurricane style fan. As long as it will gently and continuously push out the trapped hot air that's good enough. Quiet fans pay for themselves when you go into the studio.

This can give you an increase in tube life of several times, at least!

So that's what I learned from those old folks, for what it's worth. Hopefully it's useful.

:food-smiley-004:

[greco]

Thanks Wild Bill...You write so well and I always enjoy your posts.:bow:

I'm waiting patiently for your electronics textbook to be written.

All the best

Dave

[Ripper]

Tubes LOVE fans! Power tubes for audio and radio transmitters usually had forced air blowers. Guitar amps can almost always benefit from even a small fan like those found in a computer power supply. I like to scrounge those 'cuz first, you can find old computers in garbage cans and second, they're 12 volt DC fans. Usually you can steal some AC voltage from the filament winding and rectify it with a filter cap of a couple of thousand microfarad at 16 volts or better. This will give you maybe 8-9 volts of DC under load to run the fan.

When you run a 12 volt DC fan under voltage it turns quieter and more slowly. You don't have to run a hurricane style fan. As long as it will gently and continuously push out the trapped hot air that's good enough. Quiet fans pay for themselves when you go into the studio.

This can give you an increase in tube life of several times, at least!
:food-smiley-004:

120mm and 92mm fans work great for this. They spin slow and quite and you can even get some with led's for those who want to pimp things out.

[unison thrush]

Make sure there is no rain coming in the window. :tongue: