I don't doubt that yours and other of a certain time period were 3/4" ply. As of 2016, and maybe before, the only plywood is in the baffle. I sent Fender a message. They have not responded. False advertising.
Actually, the baffle-board in the BJ is already made of plywood (y)I could easily make a plywood baffle, is it worth it tonally?
Indeed, I had a number of BillM mods done on my '90's Greenboard Blues Jr. I put in a Celestion Greenback (also BillM's recommendation). It has a Heyboer transformer, as well. This on is a keeper.I seem to recall that he became quite renowned for mods to the BJ?
Do you per chance Have a copy of the schematic you can share? So far I have not been able to obtain one for the IV jr.As far as I can tell after looking at my 240V export black tolex Fender Blues Junior IV, manufactured 2021, the changes to the circuit as used in a BJ IV Rev.A as compared to BJ III Rev.D:
- pcb is black with white writing
- C4 changed to 2.2uF from 22uF
- C8 changed to 0.022uF from 0.0022uF
- Fixed bias power supply components removed from power section
- Cathode bias added - C10 - 22 uF, C33 - 22 uF, R51 - 270 ohms, R52 - 270 ohms, R31 & R32 connected to ground
- Reverb input now taken from plate of V1-A before tone controls
- Resonance circuit added in NFB path
The baffle board is made from 10.5 mm plywood. Don't know wood type but is very lightweight & dents easily.
Plenty of barroom guys gig with a BJ. I hear it here and I’ve heard it in person.
There should be youtube videos comparing the version(s) since this a very Popular amp but from HRD experience... In reality it should be 2-3 resistors and 1-2 capacitors they changedit's impossible to know what the difference is.
I shouldve made a more particular rather than a general point but the latter seemed funnier. Anyway, point being that both the PJ and the BJ had the power tubes biased hotter than standard which lead to various heat issues mainly at the actual valve sockets. Plus low value screen resistors close to the board. Those were as i recall some of the issues BillM tackled.For or against?