Novice at Analog, need recommendations.

I am a Novice at Analog Record playing. Spent most of the last 15 years listening to CD. Current System consists of a refurbished Thorens TD-160 Turntable with a new Grado Silver Cartridge, Space Tech Lab P-102 Vacuum Tube Phono Stage, Space Tech Lab A-102 Integrated/Headphone Vacuum Tube Amp, driving a pair of Grado RS-1's. Mid-range sounds very weak, and so does low level information. The Cartridge was aligned by reputable, and knowledgable dealer. Can this be the Cartridge is not broken in yet? Could it be the Phono-stage? Any recommendations for improvement and up-grading? A-102 and RS-1 sound great with Digital/Analog front end.
Don't know your System, but analog has normally no big secrets.
I guess, it is the matching between Cartridge and Phonostage datas (Gain)
Hmm..Grados have a lot of things going on, but weak midrange is usually not one of them. What are you comparing it to CD replay? If so, what CD player.

My shot-in-the-dark guess is that the VTA is not correct on your setup. Grados sometimes like the back of the arm downward. Is it possible to lower the rear of the arm? If this is not possible, cut out a few cardboard circles the same size as the platter and place them on top of the platter, but under the mat of course you will have to punch, or cut a center hole in them for the spindle to fit through. By raising the cartridge, it is the same as lowering the back of the tonearm. Give it a try and please report if this begins moving things in the correct direction.
One more thought, make sure that your phono preamp is set to MM caridge gain, and most importantly, that the load is either 47K ohms or 10K ohms.
Novice responding,
Thanks for the suggestions. Phonostage is set for MM Cartridge gain, load is 47K ohms. I was comparing to this Turntable with a Grado Black Cartridge and some other Phonostage I am not sure of. It was a set-up the dealer had arranged. I chose the Grado Silver to replace the Black, I also chose the Space Tech Lab P-102 with Tubed MM Output Stage and Tubed Power Rectifier. This Mid-range suckout seems to come and go, usually leaves after playing numerous records in a row. I was thinking that it was just the Cartridge breaking in. Does anyone know how long the Cartridge should take to break in? I only have maybe 20 hrs. on this Cartridge. It is a brand new Cartridge. I was just wondering if I might have some other problem. I can try the suggestion with the cardboard and the VTA. If the sound goes in the right direction, then the VTA is way off and has to be adjusted.