• 09-27-2008, 10:07 AM
    Whats the diff between Adcom GFA-545 and GFA-545II Power amps
    I was wondering whats the difference between the Adcom GFA-545 and GFA-545II Power amps? I noticed the GFA-545II sells for about $75 more on ebay then the GFA-545.

    Also whats with the GFA-555 MK2 amp? Why is this one so dang expensive compared to the 545 and 545II?

    Some history on these amps would be nice. Thank you.
  • 09-27-2008, 01:18 PM
    Adcom explains the upgrade from GFA-545 to GFA-545 II in the manual for the GFA-545 II here:


    And I guess the beauty of the GFA-555 II is the power...200 wpc continuous average power at any frequency 20 to 20k at 8 Ohms with 0.04% THD seems pretty impressive. 325 wpc at 4 Ohms and 600 watts bridged. Plus they supposedly sound nice. I have a GFA-545 II and I think it sounds nice, although a tiny bit bright. I sometimes turn down the treble.
  • 01-05-2012, 05:32 PM
    I have just picked up a mint pair of 1980 Ininity RS4 speakers and am looking for an amp to drive them. I have found a, still in the box- know the guy selling, ADCOM GFA 545 -II and GTP 500-II.
    Think this would do the job.
    New at this so hope I have done correctly .
  • 01-07-2012, 03:11 PM
    JoeE SP9
    I currently use a pair of 545's to drive the rear ESl's and rear sub woofer in my system. Those same 545's have at times driven my front ESL's. IMO the 545/5400 series are the sweet spot in the Adcom lineup. Sure the 555/5500 and 585 mono's have more power but to me they lose a little of the delicacy and sweetness of the 54 models. I've never tried the 535/5300 series they are a bit underpowered for me.

    I should mention the 545/5400 models seem to push more Watt's than their ratings would suggest. This is true for all Adcom power amps.

    TBH, I never been as impressed by their tuner preamps. This also applies to their preamps except the 585.