NAD 3020A Integrated Amp


So I have a series of questions re: a NAD 3020A I just bought on Ebay. I'm just getting started on trying to build a good system so please excuse my lack of knowledge.

1. NAD 3020A Amp hooked to JBL 4312A Control Monitors and new REGA RP-1 Turntable. NAD is replacing a early 90's Sansui RZ-1000. I would have thought there would have been an appreciable difference in sound quality but I'm not sure that there is. Can't tell if it better, worse or just different.

2. NAD delivers a electrical snap sound to the speaker which Sansui did not. Is this cause for concern? Should I have this unit tested / looked over?

3. As this is an older amp it has limited inputs. Is it ok to run IPOD or DVD into the AUX input? Also no CD input, any ideas?
Nate
iamnate
1) The NAD is a nice amp, but so were some of the Sansui offerings, though I am not familiar with the RZ-1000.
2) When does the "SNAP" sound occur? Is it when power is turned on? This could be a capacitor issue and may need to be looked at (I bought my 3020A new in 1979, i believe, so yours has a few years on it)
3) Any input except the phono will be fine to use with the CD, IPOD, or DVD. The Aux and Tape input were designed for line level voltage inputs as apposed to the very low voltage of the phono.

Great low power amp that has a smooth presentation. One of the units in my journey I regret letting get away.
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Thank you. Drrsutliff: The snap occurs when I power on and off.
I do like the way it sounds, but compared to the Sansui it sounds a little tinny or something. I'm wondering if maybe it doesn't have the power to handle the speakers.

Viridian: Thanks for clarifying inputs.