CAT SL-1 Reference repair


I recently bought a CAT SL-1 Reference preamp. The line stage is great. But the phono stage doesn't work properly. I crank up the max volume but it doesn't give reasonable listening level and it became too noisy. The sound is dry and week.  It doesn't balance well either.  I replace all the tubes in phono stage but without luck. Anybody has a schematic of this preamp? I didn't find anything on internet. Any suggestion is appreciated. Thank you.
cygnus_859
Are you using a MM or MC cartridge? There are loading plugs for the MC's if they are low output.

best to call CAT in upstate NY & have them repair it. They know their products well & can fix any of their old products.
You will never find a sch of any of their products on the web as they never release any of this info. All of their topologies are proprietary & many of the internal components are also proprietary. If you’ve opened the box you’ll see that none of the caps have any values on them - just a catalog number. The CAT factory has the decoder key to match catalog number to cap value.
Let the factory take a look & tell you what’s wrong....
excellent preamp, if i may say so.