Originally Posted by Slare
JBL built the PT800's with at least two different PN tweeters, the later ones had the washers installed. I have no opinion as to which PN is better or worse (I can't tell a difference) but I know they used at least two PN's from the factory, so there are at least three total PN's including the current service part that are acceptable. Why they did this I cannot say, but it is absolutely true.
Being one is replacing a Ti with another Ti there would not be much, if any difference. Replace a Ti with a soft dome, for instance, and then you will hear a big difference.
I'm the same guy that also troubleshot the chance of PS1400's having reversed terminals, and that there are two different finishes on the waveguide, the later finish being a bit more matte and just slightly lighter.
Finding reversed terminals would be the result of someone not paying attention during assembly. I found the same thing last year on my new Marantz TT, that came with an $800 cartridge. It just did not sound right, thin with no phantom center. I looked at the pin connections again, they were right. Then on a hunch I reversed two of the wires at the cartridge, and sure enough, it was all good.
Not my info, but the PS1400 amplifiers were also upgraded late in production, though nobody has been able to give a specific explanation of how or why they were changed. My guess would fitment of better quality or more conservative caps.
There were a number of amp failures early production, it was quite common. I never had a PS1400, as I had already bought a pair of SUB1500s drivers for $250/ea and built my own subs almost 3 years before I bought 5 PT800s. And the 1500s go much deeper <20 htz. And one of the best movies to show off that deep bass is Shooter
, feel the pressure on your chest and pant legs blowing in the resulting wind.