Feb 12th, 2024
My circuit alterations are very neatly done and can be undone if required. The unit in general will be less buzz saw sounding and can be easier to program warm tube overdrive sound into it. Ultimately, the unit will have Voicings which can be made more intense or subtle, i.e. more crank, or more silky overdrive, or cleaner for the Acoustic sound. ADA's engineers and I, about 20 years ago, would swap ideas and the engineer who developed this product apparently later included some of my modification into the MP2. I did this same modification for many serious pro players in the 1980s. The cost is $300.00 which includes all cost of parts and return shipping (parts may be tubes, connectors, or capacitors, about 20 parts maybe installed.)
The modification consists of upgrading some crucial parts which will age badly, i.e. High Voltage capacitors and diodes. Also, modified is the equalization of the tube front end which presently is mostly just a linear frequency response tube gain stage, into a more correct equalization for guitar pick-up. This allows the preamp to be quieter and more electric and vibrantly acoustic sounding when the gain / distortion e. q. parameters are adjusted.
Contrary to the popular belief, it is not the tube which makes the most difference in performance. It is the users ability to understand how to program multiple stages of Voicing done by changing the tubes gain staging and equalization. This is because the preamps almost novel design uses a basic little computer to change the cathode bias and the gain of a tube at the users programming. Therefore these parameters affect the tubes operational sound quality far more than simply changing a tube. If someone prefers a certain 12AX7 tube, adjusting these parameters carefully can make one tube sound like another. In fact, even as the tubes age typically one can reduce the overdrive easily to make the tube less fuzzed out or add extra gain to give more punch or thickness to the sound.