Difference between Dynaco PAT-4/5?

[cary]

What is the difference between the Dynaco PAT-4 and the PAT-5?

 

[sregor]

Lots of little differences. Main difference was PAT-4 used simple, discrete transistor design, PAT-5 used ICs. Early PAT-5 used LM301, later use FET input (LF357?) ICs. You should be able to find lots of info on either if you search for it.

 

[audiomagnate]

Another difference is that when the PAT5 came out many reviewers (J Gordon Holt of Stereophile fame in particular) who detested the sound of PAT4 gushed about how great the PAT5 sounded. Lots of PAS3 owners who had passed on the PAT4 ran out and got a PAT5, only to eventually return to the PAS3.