The button at the front of the PSU switches off the regulator pass devices.
Interesting. What's the power consumption when powered "off"? If you have one of those measuring devices...
Here is the GB thread: Interest for Potential GB for F5X Preamp
Please check post #40 for schedule.
Please check post #40 for schedule.
F5X Pre with a Gain of 3 ?
There is a request for the preamp with less gain.
Normally I recommend that you do not use the attenuator at any level higher than -10dB.
So with a source output of 2Vrms per phase, you will have max input to the pre at +/-0.9V per phase.
With a gain of 3, you will just get back 2Vrms at the output.
This is fine for directly connection to the F5X power amp.
But if you have a power amp with higher rails, you might want more output.
Or you have an active crossover in between, you can easily lose 6 to 10 dB.
So do bear that in mind.
I've more or less worked out how to reduce gain to 3x in simulation.
But I want to have it tested before publication.
GB subscribers will have access to the spice files at the usual location.
Maybe in a few weeks' time.
Patrick
There is a request for the preamp with less gain.
Normally I recommend that you do not use the attenuator at any level higher than -10dB.
So with a source output of 2Vrms per phase, you will have max input to the pre at +/-0.9V per phase.
With a gain of 3, you will just get back 2Vrms at the output.
This is fine for directly connection to the F5X power amp.
But if you have a power amp with higher rails, you might want more output.
Or you have an active crossover in between, you can easily lose 6 to 10 dB.
So do bear that in mind.
I've more or less worked out how to reduce gain to 3x in simulation.
But I want to have it tested before publication.
GB subscribers will have access to the spice files at the usual location.
Maybe in a few weeks' time.
Patrick
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