Should I try the Cambridge Audio 640p?

I dont think you will see much of an improvement. I have the PL2 and had the phono board and got a Parasound Zphono with a TT and did not see much of a change. The Cambridge gets mentioned in the same list with the Zphono. And a number of folks say the Primaluna board is very good.

If you are looking for a big change then expect to spend about 400-600. I went to a Pro-ject Tube Box SE and really like the sound and have been able to change it by swapping tubes (Brimar CV4004 to Sylvania 12ax7wa). The Jolida, Graham Slee, Lehman Black Box are in this range used and mentioned frequently here.

I would be willing to go to the 400-600 range.....thanks for the response.

There is a Phonomena Nova just listed for $600. It is outstanding. Retail is $1000. It is not mine and I don't know the seller. It will go fast.

I'm using a Gram Slee Gram Amp 2 with my phono rig and enjoy it quite a bit. Keep an eye out for other Gram Slee phono preamps, they are very highly regarded by those in the know...

-RW-