Been itching to build a tube preamp, hopefully it will turn out better than my last overdrive pedal which had way to much noise. Perhaps a pcb would be better than a protoboard?
Why does it say that a lowpass filter set at 5kHz sounds "creamy"? I think it sounds muffled like an old AM radio. Most of the important high frequencies are missing.
(Let's not discuss very old, very distorted telephones where they cut the high frequency distortion above only 3kHz).
Someone said they've had problems reading the PDF, so I converted it to a TIFF file, zipped it and split it in two, to circumvent the maximum file size of 10MB per attachment.