I use a Parasound A51 amp to drive four TS-150 (rear and side surrounds) and a center channel that is a VR4 JR. (I tried a LCR15 center, but found I preferred a center that matched my left and right front speakers.) The Parasound A51 is probably overkill for the TS-150, but I wanted an amp similar to the Parasound A21 driving the left and right front speakers. Most would consider a Krell amp a step up from my amps.
Almost any Krell amp would likely easily power the TS-150 and LCR-15. Does a Krell amp drive your other channels?