"02-18-15: Johnnyb53
The TAD 150 Signature's phono stage is made for high output cartridges. The OP's Lyra Clavis puts out a low 0.25mV."
That should be what's wrong. If you're using a low output cartridge with a low output phono stage, the system should sound exactly like you describe. Try connecting a regular line level Source component to one of the other inputs on you preamp. (CD/DVD player would be best, and it doesen't have to be anything high end. Any player will do). Just make sure not to connect it to the phono input, it has to be one of the others. If the system works OK, then you're going to have to change something in your TT setup.