pinebox
Well-known member
- Joined
- Mar 11, 2015
- Messages
- 119
Hello, my friend has an Amek I am refurbishing for him, and he has a lot of variance in microphone level across the console measured at the insert send right after the mic pre. I am thinking the transistors are suspect, since its design requires five ZTX214s on each side of the signal. He has one module that was reworked by Jim Williams, part of which was removing the ten ZT214s and replacing them with two 2sa1084s. He was told to just copy these mods but these 1084s are long out of production. I found another thread discussing the KSA992B as a possible replacement in a similar Amek preamp. This is more into preamp design than I am familiar with, would this be a drop in replacement or would I need to recalculate R8 and R9 to a new value. (I am assuming that these were changed on the JW mod looking at the board, I would use this updated value going forward) Any advice on what to read to learn about this would be great, thanks!