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Old 22nd June 2005, 03:30 AM   #1
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Hi guys,

My trans is specified is to be used at 35-50mA. However, currently I am running it at much higher current (60-70). Does this have effect on the trans?
I dont know if it saturates or not, but so far it sounds fine. And the voltages measures ok, the trans does not get hot. Is this ok?
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Old 22nd June 2005, 05:07 AM   #2
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Could lead to shorter life and reduced bottom end. Unless it's a decent product, which then are conservatively rated anyway...

What brand?
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Old 22nd June 2005, 05:59 AM   #3
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Ya, it is SE, 5k trans. I am using it for 2a3, which I think it looks good on paper.
Shorter life you mean for the tubes?

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Old 22nd June 2005, 11:49 AM   #4
SHiFTY is offline SHiFTY  New Zealand
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Should be fine, I would guess. The core might be saturating a little, but I would guess you would really notice if it was too bad- core saturation gives some naaaasty distortion. However seeing that a 2A3 only puts out a couple of watts anyway, shouldn't be a problem. You might not get great bass response though, if its on the edge of saturation.

I use some SE transformers designed for EL84 in my 2A3 amp, and no problems thus far. The manufacturer probably put a little bit of extra current capacity,

I can't imagine how it would shorten the life of the tubes or transformers- generally transformers either work fine or not at all.

If you were really worried, whack a bigger cathode resistor in the power tube to lower the current a bit.
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Old 22nd June 2005, 01:28 PM   #5
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I think it sould be no problem if the transformer doesn't get too hot. Some trans manufacturer will reserve a little extra current for safety purposes.
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Old 22nd June 2005, 01:51 PM   #6
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ok, thanks guys

I surely didnt notice distortion (at reasonable volume) nor heat issues. Bass is not very deep, but I think I can live with it for the moment. Might whack a bigger resistor for fun of it.

5k looks good for 2a3 on paper anyway :-)
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Old 23rd June 2005, 06:36 AM   #7
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A fully loaded transformer tends to give better regulation any ways. That is, the output voltage will be more resistant to change if the input voltage changes breifly and slightly

Most transformers have very genourous overload ratings. On the order of 200% for 30 seconds. However, I am sure there is a duty cycle associated with this

Unless something went haywire with your grid, I don't think you will have an issue
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