I've done update/modifications to both. The Dynaco is a lot better place to start!
We still do updates to the PAS-2/PAS-3, with an updated phono section, a nice line stage (no tone controls), stepped volume control and power supply regulation. They turn out rather well :)
Kit-built PAS preamps are what you are most likely to run into. The layout was hard to make the selector switch/input wiring look very neat, and if you are are thinking up updating/upgrading the unit it will not be any worries. Just make sure that the unit works- any serious update will be replacing all the filter caps so there are no worries if it hums- you're going to have to replace the filter caps even if you keep it stock. The same is true of the EICO.
We still do updates to the PAS-2/PAS-3, with an updated phono section, a nice line stage (no tone controls), stepped volume control and power supply regulation. They turn out rather well :)
Kit-built PAS preamps are what you are most likely to run into. The layout was hard to make the selector switch/input wiring look very neat, and if you are are thinking up updating/upgrading the unit it will not be any worries. Just make sure that the unit works- any serious update will be replacing all the filter caps so there are no worries if it hums- you're going to have to replace the filter caps even if you keep it stock. The same is true of the EICO.