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Re: Building a vacuum tube tape preamp

Some updates on this project. I've really learned quite a bit in building this preamp, mostly from online contacts. I've enlisted the help of a fellow in the UK who helped me with mathematical modeling of the circuit. And, also curiously from ChatGTP, who I refer to as "Chatbot" to my wife. I found it to be pretty amazing, I ask it to analyze some data that I feed it and it scrolls out a detailed description of what happened and the mathematical explanation and makes very detailed recommendations on what I should do next. The better my question the more helpful the answers. It's not perfect, I've found a couple of instances where it was wrong and I've corrected it. But, it can do mathematical computations and give answers that are very helpful. I measure the playback frequency response with a calibrated test tape and it suggests component changes that will result in flatter response. I order the parts and when they arrive put them in the circuit and re-measure the results and feed them to Chatbot. Here is my current playback response:

SeleniumFalcon

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Re: My 2024 Polk SDA 2b Modification Progress Thread (Drop1)

Factory braces are still in-place. So here's a pic with the polyfill in the cabinet. It fills the space just under the center brace and folds over itself to stay out of the way of the passive radiator. It's already getting pretty tight behind the MWs and I haven't even added the BH5 yet. Current plan is to add the dowels at just the point where the polyfill ends.