seems as there are lots of hi fi people on here i might as well ask

i've got a pair of B&W 601 speakers connected too a rotel ra931 mk2 amp

one day a tweeter blew and i had it repaired the amp also needed a new fuse so i changed that but a little while later it blew the tweeter and fuse again any ideas?

Is the crossover in the speaker ok?? Difficult to check, but a possiblity.

Could be a shorted capacitor in the crossover, does one speaker sound much "brighter", possibly even somewhat harsh at the top end?

If the power amp is oscillating at high enough frequency, that will also cause damage to the tweeter, without being (very) audible.

I had a Nad amp that did that .It would blow the tweeter on one channell on any speaker conected at any time it liked ..I had it tested and retested ,It kept coming back no fault found so last time I never bothered collecting it back..