Hi All,
I've been learning tube equipment through the world of repairs but have been getting more into DIY builds recently. Wanted to make a dead simple tube preamp/DI for guitar that I could slowly build off of, so just the preamp of a Fender 5E1 seems like a great start. I could add tone controls after I get the basics working. Open to output being unbalanced or balanced, for sending into a mixer channel strip / interface, or into a power amp.
Looking at a few schematics and sifting through some forums I've gathered and am confused by a few potential possibilities and what is technically sound. Tapping off of the output side of the coupling capacitor coming off the plate Ive come across different additional connections. Keeping it as simple as possible right now, avoiding a buffer stage at least for now would be ideal (unless deemed necessary).
Without a transformer, am I able to go straight to Tip of 1/4" out off of the coupling cap? Or do I need to provide an additional ground reference post-cap with a resistor from tip to ground, choosing a value based on frequency response? Instead of a resistor, I've seen send jacks use a potentiometer to act as a level control?
Using an output transformer I get the added possibility of additional distortion, a balanced output and impedance matching, seems like a win other than cost. What would an ideal ratio be for impedance purposes. 10k : 600/150? Or something higher like 30k:600?
If I wanted the option of an unbalanced out in addition to the transformer route, can they be used simultaneously, or would I need to use a switching jack to disconnect the connection going to the primary of the transformer if I wanted to go the unbalanced route?
Thanks.
I've been learning tube equipment through the world of repairs but have been getting more into DIY builds recently. Wanted to make a dead simple tube preamp/DI for guitar that I could slowly build off of, so just the preamp of a Fender 5E1 seems like a great start. I could add tone controls after I get the basics working. Open to output being unbalanced or balanced, for sending into a mixer channel strip / interface, or into a power amp.
Looking at a few schematics and sifting through some forums I've gathered and am confused by a few potential possibilities and what is technically sound. Tapping off of the output side of the coupling capacitor coming off the plate Ive come across different additional connections. Keeping it as simple as possible right now, avoiding a buffer stage at least for now would be ideal (unless deemed necessary).
Without a transformer, am I able to go straight to Tip of 1/4" out off of the coupling cap? Or do I need to provide an additional ground reference post-cap with a resistor from tip to ground, choosing a value based on frequency response? Instead of a resistor, I've seen send jacks use a potentiometer to act as a level control?
Using an output transformer I get the added possibility of additional distortion, a balanced output and impedance matching, seems like a win other than cost. What would an ideal ratio be for impedance purposes. 10k : 600/150? Or something higher like 30k:600?
If I wanted the option of an unbalanced out in addition to the transformer route, can they be used simultaneously, or would I need to use a switching jack to disconnect the connection going to the primary of the transformer if I wanted to go the unbalanced route?
Thanks.
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