Biggest "bang for the buck" audio gear you have owned(in your history)?

This is very subjective, and your opinion on your own systems/items is all that really counts.

From the beginning to now, these would fit that category for me: (in no order)

Original Large Advents
Dahlquist DQ-10
Conrad Johnson ART pre.
Original Monster interconnects and speaker wires.
Nakamichi SR-3a
AR Turntable
Audio Research LS-12
Magnepan 1.6
Magnepan 20
Wireworld Gold Eclipse III
Audio Technica Electret Condenser headphones 
Magnum Dynalab Etude and 108 tuners
Magnum Dynalab Receiver (original)
And in those "early days" special pressings and imported Jazz albums. 

There may be others I am forgetting, but these were very good items along my journey. 

I was pleased to see the Large Advents mentioned.

 Large Advents
LBL L-100
Dahlquist dq-20s
Hafler Amp and pre-amp I built 
Roger Modjeski pre-amp

They all brought good music at great value but the only one I widh I had not sold was the Roger Modjeski pre-amp.


First “real” high-end system: Bose 901 series 3; Kenwood integrated amp, Revox reel to reel deck, Nakamichi cassette deck, Empire LP Turntable and cartridge; DBX-3BX compressor / expander; kit-built Dynaco FM-3 tuner. 
Bought new in 1988 Cerwin Vega D3.  They lasted forever and sounded good from day 1.  Not the best speakers in the world but a huge value for the money.
Also, Foobar2000 audio player.  Free.  Hugely customizable.  And when coupled with the $3 Foobar2000 Controller Pro app, super convenient.
3 pairs of Magnepans - 1 pair in each of the last three decades
Technics SL1200 turntable
Conrad Johnson amp
Apt Holman pre-amp