Hello all,
I’m wanting to build a Two Rock style tube preamp pedal. What is the best way to ensure a low output impedance? What’s the easiest way? Open to all suggestions.
Tube preamp pedal output impedance
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Stevem
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Re: Tube preamp pedal output impedance
If you want low output impeadance then the output jack should be driven by a Cathode follower circuit.
These type stages have a hair less then unity gain so the gain stage before the follower will need to provide the signal level your looking to have available.
These type stages have a hair less then unity gain so the gain stage before the follower will need to provide the signal level your looking to have available.
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Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Re: Tube preamp pedal output impedance
Depending how "pure" you want to be, you could also use a MOSFET source follower on the output, so you could save the triode for gain instead.
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Andy Le Blanc
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1 others liked this
Re: Tube preamp pedal output impedance
in case you opt for a Mosfet, the LND150 can withstand tube-like voltage (up to 500V) and can be a direct replacement without changing a normal cathode follower topology (of course not in a tube socket) and it's dead cheap (pennies). It is widely used for this purpose.