Well, the phono cards are stereo.. they have an opamp in the circuitry but they let no sound through for one reason or another which is why I'll probably have to put a normal line preamp after them to get some gain (they're 35dB@1Khz whereas the line preamps are 40dB.. the phono input impedance is 47kOhm and the lines output are 1kOhm)
The gain pots in the front panel are wired from the circuitry trimmers (which are post opamp, the originals in the kit were 1K) to 100K dual log pots so the range is a bit questionable, but due to a number of reasons I can't be bothered to switch them to 1K at the moment. Funny that you mentioned potentiometers; the ALPS ones are actually nice but they're PCB mount (they have no wire holes in them) which means they have to be soldered with care.
Anyway, I managed to break the headphone amp which has been a lot of trouble, due to desoldering etc.. those kit PCB's are small but they're also prone to all sorts of damage. Actually I was desoldering a LED from the board to the front panel so as of now the monitoring is "kaputt".. I'll try to fix it at some point. (edit : I've also been looking at this as an alternative to the current headphone amp)
EDIT : I actually put a bigger LED in the headphone amp circuitry with jumper wires.. it's a bit brighter with 6V (the headphone amp board operates at 4,5V) and it's also modified to mono (I was thinking of putting a resistor or two in the summing)
EDIT 2 : I also applied to an electronics polytechnic.. although I highly doubt I'll make it in this time either (this is the 3rd time I've been taking part in the polytechnic application process) since they're most likely not interested in a hobbyist with a black plastic box with a red LED and a few potentiometers in it.
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