Does anyone know if the Nakamichi TA3A and TA4A have identical preamplifier sections? I'm using a friends Ta4A now with an external amp but its a bit out of my budget but since I don't need the amp section I was wondering if 3a would be identical as far as the entire preamp section like features, line stage, phono, fm. 
Retired now, but worked in the A/V industry for 25 years with some Nakamichi experience. My gut feeling is that they are identical, but if not, they should be extremely close.
I've googled and googled, I guess I can try to find a list of specs and see if all the frequency response and things are the same