New Member Needs Help

Hello everyone.  I am a new member and could really use some advice.  First, I hope I am posting this in the right section since I suspect the problem lies in the area of my electronics, although admittedly I am not sure.  I was a budding audiophile in my younger days and accrued some equipment, all bought new.  It consists of an Adcom GFA-555 amp, Adcom GTP-500 preamp/tuner, Adcom GCD-700 CD player and a B&O Beogram 1700 turntable.  I am using a set of Soundwave Grand Soliloquy speakers.   My wife would sometimes turn on the equipment for background music but there really hasn't been any serious listening in years.  

Having just retired I now have some free time, so after checking all the connections, I began listening to the system using the CD player as the source.  Overall, I thought it sounded very disappointing - pretty harsh and a bit thin, lacking in bass.  I couldn't listen to it very long.  I then tried the turntable.  The sound wasn't much different but the belt on the TT must be shot and the resulting rumble made serious listening difficult.

Having done some searching on this forum, I decided to pull the speaker cloth and examine the Grand Soliloquy speakers.  They looked perfect.  The cones and surrounds were butyl? rubber and looked good, as did the glue, which I read was a weak spot on some early model Soliloquys.  

So now I am wondering where to go next.  Could the amp/preamp have deteriorated that much with time?   Is that something I would audibly notice?  Would the crossovers in the speakers deteriorate over time?  Or maybe it is just my memory and I don't remember the sound very accurately?  And is any of this equipment up to today's standards and worth saving?  

I also have a pair of Ohm Walsh 2 speakers and an old Harmon Kardon HK730 receiver packed away that I could haul out for a comparison, but I am not sure that will answer any questions, and might confuse me more.  I appreciate any and all ideas from forum members.  Oh, and my room is large - about 14X22 feet.  Sorry for rambling a bit but thanks very much in advance.  
jpl