Dumble discussion

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jazzbass
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Dumble discussion

Post by jazzbass »

Hi everyone,

I purchased a Hammond 1750D, 2350 ohm C / T, 4/8/16 ohm 100Watt output transformer to power a quartet of 6L6 in a JM / Wonderland project. I didn't notice when I ordered it that this transformer also has an extra Feed Back winding. It is described as a winding to reduce noise and distortion, can someone explain to me how it is implemented in a musical instrument amplifier?

Thanks

Franco
franco mezzalira
talbany
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Re: Dumble discussion

Post by talbany »

jazzbass wrote: Thu Apr 14, 2022 4:32 pm Hi everyone,

I purchased a Hammond 1750D, 2350 ohm C / T, 4/8/16 ohm 100Watt output transformer to power a quartet of 6L6 in a JM / Wonderland project. I didn't notice when I ordered it that this transformer also has an extra Feed Back winding. It is described as a winding to reduce noise and distortion, can someone explain to me how it is implemented in a musical instrument amplifier?

Thanks

Franco
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martin manning
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Re: Dumble discussion

Post by martin manning »

Hammond 1750D has a dedicated feedback winding, essentially a very low impedance secondary, that can be used as a source for feedback voltage. You could use that instead of one of the speaker taps, or just ignore it. It is not a UL transformer.
jazzbass
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Re: Dumble discussion

Post by jazzbass »

Hi guys,

thank you talbany and tank you Martin, and again Happy Easter to all.

Franco
franco mezzalira
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