Hello !
Do you think that this OPT will be ok with 160 ma ?
FC-40-2.7S – ISO TRANSFORMERS
It is for a 100TH A2 amplifier under 550volts.
Thank you, GILLES.
Do you think that this OPT will be ok with 160 ma ?
FC-40-2.7S – ISO TRANSFORMERS
It is for a 100TH A2 amplifier under 550volts.
Thank you, GILLES.
It says “under 100mA recommended”... You want to do 60% more than that? You may be lucky, but don’t expect 100% reliability or safety.
Regards, Gerrit
Regards, Gerrit
Separate from heating, possible destruction, etc. . . .
160Ma DC on a 100mA tranformer generally = no bass, always saturated, bass to mid/high Intermodulation distortion.
Other than that, go ahead and use it that way.
160Ma DC on a 100mA tranformer generally = no bass, always saturated, bass to mid/high Intermodulation distortion.
Other than that, go ahead and use it that way.
So...this is a "40W transformer" that you can only bias at a point that will give you 13.5W max.
Did the transformer designer think this through? At that primary impedance, you really need a bias point at 160mA+ to get up to the transformer's rated power, at which point the core isn't up to the task for low frequencies.
Seems like a more appropriate rating would be 13.5W
Did the transformer designer think this through? At that primary impedance, you really need a bias point at 160mA+ to get up to the transformer's rated power, at which point the core isn't up to the task for low frequencies.
Seems like a more appropriate rating would be 13.5W
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It is clearly rated for 300mA. So it will be "OK" depending what you mean by OK. It should not smoke. It probably won't show 25 Henry inductance, or support 40 Watts down to 30Hz. Then you may want to stick to 100mA. But who needs 30Hz? Who puts all his 40 Watts at 30Hz?
Not that a 100TH can deliver anything like 40 Watts audio.
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Right, but they drew all of the performance curves at a lower-power bias point. Disappointing. What's performance look like at rated power? We have no idea.
PRR, I am getting 19W out of an 826 into a 5k transformer and will be subbing in a 100TH soon. I'll be putting 35W into the primary of the transformer for sure at the new bias point. Why don't you think that's doable?
PRR, I am getting 19W out of an 826 into a 5k transformer and will be subbing in a 100TH soon. I'll be putting 35W into the primary of the transformer for sure at the new bias point. Why don't you think that's doable?
Bode plots are run at RMS output, you don't need 15hz, nor 90khz, 300ma/1.41 > 100ma, but the real problem i see is that the plot is for a very low impedance compared to what usual tube running at 550v 160ma can drive...so i'm not sure if the tube will be even able to drive the full poer out of that trafo.