Hi Revintage,
Most linestage OPTs are rated with an output impedance
of 600 ohms. Amp OPTs are 4,8 or 16 ohms. Assuming
that the input is 5K & using a 6n6p, would it work as a
linestage? If gain is too low, we can add another input stage.
Ofcourse this would turn it into an amp. Sorry if it sounds stupid I'm just curious.
Thank for the advice
Most linestage OPTs are rated with an output impedance
of 600 ohms. Amp OPTs are 4,8 or 16 ohms. Assuming
that the input is 5K & using a 6n6p, would it work as a
linestage? If gain is too low, we can add another input stage.
Ofcourse this would turn it into an amp. Sorry if it sounds stupid I'm just curious.
Thank for the advice
hey-Hey!!!,
A 5k:16 is 17.7:1 step-down. Less than unity gain there with 6N6Pi loaded by 5k. Aside from step-down ratio, there is no issue with such devices for linestage use. The secondary won't likely have a speaker-level load applied, so the primary is mostly loading the tube with its inductance. For well-biased triodes, this is not such a large issue as it might appear on first inspection.
cheers,
Douglas
A 5k:16 is 17.7:1 step-down. Less than unity gain there with 6N6Pi loaded by 5k. Aside from step-down ratio, there is no issue with such devices for linestage use. The secondary won't likely have a speaker-level load applied, so the primary is mostly loading the tube with its inductance. For well-biased triodes, this is not such a large issue as it might appear on first inspection.
cheers,
Douglas
As revintage has stated, with enough primary inductance, it would work.
Transformers are an item that have so many compromises that they really need to be optimized for the application in order to be their best. This transformer you are using is going to be much larger than necessary and will have larger stray capacitance. This may compromise the high frequency response.
Good Luck with this.
Doug
Transformers are an item that have so many compromises that they really need to be optimized for the application in order to be their best. This transformer you are using is going to be much larger than necessary and will have larger stray capacitance. This may compromise the high frequency response.
Good Luck with this.
Doug
revintage said:Hey Douglas,
The "minus" got lost in transition. So we agree! Anyway don´t see a 5k as an option so 2,5k:16 ohm could be OK. Even if it´s just 2dB gain with 6N6. Better to go for a 5842 or 6C45 with higher mu.
hey-Hey!!!,
Seems about right... I'm currently enjoying PP 6S45 loaded with 20k:600 ( both CT ). Gain is around 5:1 at wide open volume.
cheers,
Douglas
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