Has anyone else auditioned something that really was terrible?

Been a few things.  VACs integrated, the early version.  We got it shipped in straight from the fairly positive Stereophile review. We assumed the best, told them it was broke and sent it back.  They replaced a resistor, a couple of caps and a tube.  Flat, no soundstage, not much for Dynamics.  While the boss is on the phone with VAC, I hook up a little Italian EL34 SE integrated and turn it up a bit.  Boss looks at me, the little amp, the phone, then sent it back.  Sonic Frontier's SF1 preamp was a complete dud.  Lifeless.  The old Onkyo M504 amp that is making a comeback in the market. Pretty much any Carver SS amp has a Sonic signature that makes me cringe.  Very bright, decent dynamics, but the bass is hollow.  Crown has that upward tilt but big bass.  Most of the newer behemoth amps anymore have become too bright and sterile.  Speakers?  Don't know where to begin. 
In spite of the bad stuff, there have been many very thoughtful designers who actually took our critiques seriously.  An importer we represented brought us two pairs of speakers with a glowing review in a Canadian magazine.  They weren't bad, just not up to the hype.  Recessed midrange and kind of muddy bass.  Amazingly, a box showed up one day from the manufacturer with a very nice letter explaining the modifications driven by our review.  The speakers were now quite good and did everything as we would expect.  Cairn did the same with an integrated with odd voicing.  Sent us the updated sample straight from the factory in France.  Got involved with a couple of phono stage projects as well. One from square one, 3 in development.  I miss the old industry. 

I would have said the GoldenEar Triton 1. I listened to them at my local dealer and it sounded like something was broken. After that experience I was convinced GE was terrible. Two months later I went to Axpona and the Triton 1’s were teamed up with Primaluna. I thought the combo at the show sounded absolutely fantastic, so I’m always a little hesitant to say a particular component was terrible because odds are I’m wrong. Now, something was wrong that day I listened at the dealer but it wasn’t the GoldenEar like I concluded.

A lot of the time when a system sounds bad it is due to an amplifier/speaker mismatch.Unfortunately many modern speakers are very badly designed from ease of drive perspective which means they are likely to sound bad with a lot of amplifiers.I was recently reading a Hi Fi News with a roundup of the best speakers for the year and they were just about all difficult loads-typically dipping down to under 3 ohms in the bass where they should be more like 5-10 ohms .Focal Sopra was one but there was even worse loads than them [Wilson for example].These are amplifier hostile speakers!Speakers like this should not be recommended by anybody.

RE; Mismatched components.  Yes, if an amp is such a cheap design that the power supply will not driver certain speakers, thent it is mismatched to all but efficient speakers.  I'll give an example of the difference power supplies:  The very nice, early Bryston 4B is 200 watts per channel.  The contemporary Audire Forte is 125 wpc, but has a two ohm rating of 400 wpc full range.  The Bryston uses 4 output transistors per channel, and is not rated for 2 ohms. if I remember correctly (I have a 3B.).  The Audire, 6 outputs per channel.  (Later Audire's use many more), but I think the much bigger difference is in the power supplies.  Each channel has:  Audire 500 watt tranformer and 4 x 26,000 mf's of filter capacitance;  Bryston, 375 and 2 x 4000.  My old Polaris Sumo got great reviews. It had practically no bass on my B&W 803's, and was even weak on my 38 year old B&W's.  It's new owner loves it and says it sounds the same as the one he already owns.  James Bongiorno (of Ampzilla fame), who designed some Polaris pieces, wanted no credit for the Sumo.  Nice name thought. Reverse psychology, I guess.  Yes, it has a small power supply. Even my old Phase Linear 400 lost bass at high volumes; Power supply, OK for 8 ohm speakers, but weaker than my less powerful Audire's in the bass.  WEIGHT MATTERS!

You listen to a system, including the room and its acoustics, not individual components.

It’s always possible a particular unit is defective and that should be ruled out first, but when things sound really bad most often it is because the components in the system are not good matches. SAme components in a different combo elsewhere could be the bees knees.

The most disappointing system I ever heard was a 6 digit setup at Sound By Singer in NYC a few years back. The speakers were large Peak Consult and the amp Luxman. Other systems in there sounded very good. I suspect something was defective in that setup but if so the sales guy did not seem to notice.