Phono preamp question


I'm slowly trying to upgrade my vinyl system to something that could be considered moderately decent, not necessarily high end. I have an older full feature preamp and am thinking in getting a separate phono preamp. I'm assuming the phono preamp would need to be connected to one of the line inputs. Would my preamp be the weak link if I get a good phono preamp to use with my existing preamp? Can a phono preamp be connected directly to the amplifier? FWIW, the preamp is an Adcom GTP-750. Thanks.
128x128kalali
I use a Sim Audio Moon 110lp phono preamp
( Grado high output cartridge )  
going to a Goldpoint passive preamp
that has 2 inputs ( so I can switch between vinyl and CD's )  
and a volume control going to my 
McCormack DNA-250 stereo amp and it sounds fantastic.
I believe that the less electronics the purer the music.
The idea of a passive preamp to put in between the phono stage and the amplifier makes logical sense (to me) since it appears that regardless of the quality of the phono stage the linestage is potentially always the limiting factor. So I guess the folks who spring for a very high end phono preamp must already own an equally high quality linestage pre. With that premise in mind, I think I'm better off to stick with what I have until I'm ready to upgrade my preamp.
Look for a used Audible Illusions 2C or 2D, or for about twice the money, a used 3A.  The 3A would go for about $1200 so you could get a 2D for about $600.  The 3A would be newer, however.  All these have a very good built in phono preamp and the line stage is also good.  The 3A would most likely satisfy you for a long time and through several system upgrades.  I had a 2D for about 18 years that I loved.  I bought a 3A with John Curl moving coil phono pre so I could use low output MC cartridges again.  Can't use MC with the 2C or 2D.  They both sound very good with MM cartridges.  Get a good quality SS amp to go with it and the combo will most likely be very satisfying,
i recommend the Audio Experience plus... you can buy one used at $200.  It can take mm and mid mc.   R core power supply, 6x4 rectifier and single 12ax7 input & dual 12ax7 output.    Best bang for the buck!  

FYI: A passive preamp will not work with a phono stage to drive a power amp. A few mv from a cartridge is not enough to drive a power amp that needs volts. You will never get any volume doing that.Take a look at the input sensitivity of any power amp and you will see it is rated in volts!