I would not worry about the rusty screws as if a Technician is going to work on the deck he may have new ones. Why would anyone go looking for a Akai 400D when they have a working Teac A2300SX? The Teac should forever be repairable and the Akai was junk from day one.
The heads in the pictures above can all be resolved with some Nu Finish polish which will then provide protection against further oxidation with a side advantage of bettering the tape to head contact. I have several examples of proof that the Surfactant is beneficial to a tape path even on a Tascam 42. The head shields that exist on the play heads can have Brasso a more abrasive material scrubbed to make them look way better. It is all looks but the critical part of the head is at the center of the parabola shape. Don't just change head blocks willy-nilly like some do just for wear. Ever head must be optimized as to placement and I have found that over the years head blocks for any model Studer on down do not have correct azimuth when placed on a different deck due to tape path irregularities. When you put a new block on then you need to go through the whole calibration process.
I know a lot of guys just screw them on and say they are fine- these are not professionals and they use the (some sound comes out) method of determining if the heads work. That is the same way Akai has gotten away with worn out heads all these years with plenty of marketing telling everyone their heads never wear out. The fact is 95% of decks I had come in were worn out terribly and there were no possible replacements. When I asked a client if he had any fidelity problem with his GX635D he said no. It measured -11dB at 6.3K and all the higher were much lower- I do not call these lifetime heads. I later learned that a past Akai technician said they tested the machines at 1KHz and did not worry about the high end. I wonder why that was?
The heads in the pictures above can all be resolved with some Nu Finish polish which will then provide protection against further oxidation with a side advantage of bettering the tape to head contact. I have several examples of proof that the Surfactant is beneficial to a tape path even on a Tascam 42. The head shields that exist on the play heads can have Brasso a more abrasive material scrubbed to make them look way better. It is all looks but the critical part of the head is at the center of the parabola shape. Don't just change head blocks willy-nilly like some do just for wear. Ever head must be optimized as to placement and I have found that over the years head blocks for any model Studer on down do not have correct azimuth when placed on a different deck due to tape path irregularities. When you put a new block on then you need to go through the whole calibration process.
I know a lot of guys just screw them on and say they are fine- these are not professionals and they use the (some sound comes out) method of determining if the heads work. That is the same way Akai has gotten away with worn out heads all these years with plenty of marketing telling everyone their heads never wear out. The fact is 95% of decks I had come in were worn out terribly and there were no possible replacements. When I asked a client if he had any fidelity problem with his GX635D he said no. It measured -11dB at 6.3K and all the higher were much lower- I do not call these lifetime heads. I later learned that a past Akai technician said they tested the machines at 1KHz and did not worry about the high end. I wonder why that was?
