Okay, I was thinking you were using something higher impedance and signal level than that. I'd have to try simulating it with an input signal similar to a microphone to see how it does as far as distortion, it might be fine.
I'm using Linear's LTSpice for simulations. You might want to give it a try, it's free and you can never have too many tools at your disposal.
I'm using Linear's LTSpice for simulations. You might want to give it a try, it's free and you can never have too many tools at your disposal.
hi all, i'm back at it after unpacking my electronic goodies into my new space.
i'm in the process of putting everything back on the breadboard (including the 330uf caps which really helped!) and while doing so it occurred to me i might want to ask you pros this:
Instead of 9-12v, should i crank it up to 18v for more gain and headroom?
From what i've been reading, that's the way to go for fidelity (and as mentioned, i'm not trying to do a fuzzface, instead hoping for a colorful but cleanish mic preamp).
i changed the power supply in the Sim to 18v and messed around with the biasing and it's showing around 20db more gain (82db).
Since i'd love for this to work with ribbon mics and they like a lot of gain, and as i understand it, more headroom is gonna be a good thing... are there probs i should be looking out for by doing this?
Would I be running these germs too hot?
FYI, I also picked up a "NEEWER" 48v phantom power unit (for like $12 delivered) and am hoping to integrate that into the circuit.
Latest schemo and 48v supply photo attached.
i'm in the process of putting everything back on the breadboard (including the 330uf caps which really helped!) and while doing so it occurred to me i might want to ask you pros this:
Instead of 9-12v, should i crank it up to 18v for more gain and headroom?
From what i've been reading, that's the way to go for fidelity (and as mentioned, i'm not trying to do a fuzzface, instead hoping for a colorful but cleanish mic preamp).
i changed the power supply in the Sim to 18v and messed around with the biasing and it's showing around 20db more gain (82db).
Since i'd love for this to work with ribbon mics and they like a lot of gain, and as i understand it, more headroom is gonna be a good thing... are there probs i should be looking out for by doing this?
Would I be running these germs too hot?
FYI, I also picked up a "NEEWER" 48v phantom power unit (for like $12 delivered) and am hoping to integrate that into the circuit.
Latest schemo and 48v supply photo attached.
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Hello,
More your signal is close to power supply rail more you will have THD+N (this is because you stay in the linear region of transisor operating). So go from 9-12V to 18V could be a good thing but it depends on audio signal level. If it's 1V, I don't think that there will be a difference. If audio signal is 8V, then it is a good idea to improve headroom.
In your case, your bias voltage is 1/2 of Vcc so it is 4.5V for 9V. You have 4.5V only for audio signal. With 18V of power supply, you have 9V of available signal before clipping (but less signal level for less THD+N).
More your signal is close to power supply rail more you will have THD+N (this is because you stay in the linear region of transisor operating). So go from 9-12V to 18V could be a good thing but it depends on audio signal level. If it's 1V, I don't think that there will be a difference. If audio signal is 8V, then it is a good idea to improve headroom.
In your case, your bias voltage is 1/2 of Vcc so it is 4.5V for 9V. You have 4.5V only for audio signal. With 18V of power supply, you have 9V of available signal before clipping (but less signal level for less THD+N).
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