And while Tandy's troops did mount a comeback in the second period as Jeff Hassler scored two tries to go with 15 points from the boot of Dan Biggar, it was not enough.
And the head coach was not impressed after the result with a Welsh derby against the Cardiff Blues up next in a fortnight's time.
"It was not a happy dressing room, not a happy group, and it's definitely not a happy coaching team," he said.
"We gave away too many easy points, cheap tries that Edinburgh didn't have to work for. The performance, particularly in the first half, wasn't up to our standard.
"You can't concede sloppy tries like we did and have any hope of winning games at this level, it's as clear as that. We're extremely disappointed, there is no way of dressing up this performance.
"It's pretty embarrassing if I'm honest. It doesn't represent what we stand for and it's just not good enough.
"We fought back in the second half but I'm not going to draw too much from that as it's the very least you'd expect from any team, to keep going for 80 minutes.
"Overall, it was a hugely disappointing performance with too many mistakes across the pitch, defensively and offensively, and we've got a lot of work to be done off the back of this performance."
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