Part 4: Amplifying mic level input signal

On our last blog, we talked about distortion and harmonics. http://www.fivefishaudio.com/blog/distortion-harmonics-solid-state-vs-vacuum-tubes/ and how this enriches 2nd harmonics in our signals. Here’s a nice animation showing how the 2nd harmonics get stronger the more we push our preamp harder, and note how we’re getting soft, assymetrical clipping…. thanks to our …

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Part 3: Distortion & Harmonics. Solid-State vs. Vacuum Tubes

On my last blog post (http://www.fivefishaudio.com/blog/part-2-impedances-loading-adventures-in-building-a-tube-based-mic-preamp/), I added a buffer to the output of our vacuum tube stage. This additional buffer stage lowered the output impedance, while presenting a very high input impedance to our vacuum tube stage. This will allow us to couple to the next stage …

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Part 2: Impedances & Loading – Adventures in building a Tube based Mic Preamp

On a previous blog post, I’ve been experimenting trying to build a mic preamplifier incorporating vacuum tubes. If you missed it, check it out. http://www.fivefishaudio.com/blog/adventures-in-building-a-tube-based-mic-preamp/ scope-impedance I discovered a few issues with our prototype tube preamp circuit. First, it’s the low voltage …

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