Hi Bert,
Originally, 4333A have 2231A, I have never seen a 2205 or a 2235 instead of that speaker. So the cabinet is tuned just for 2231A or H.
I don't think that using 077 instead of 2405 will improve the sound. But using new diaphragms will perhaps be a good solution.
For the filter, I changed some capacitors, those that are easy to change because they are just under the metalic grill of the filter.
For the 2420 I changed the diaphragms for D8R2425's, but be careful and
don't use D16R2425's because the medium level will be too low. That resulted in the greatest improvement.
I also changed the poor plugs on the back of the cabinets for silver plugs.
For the front grills, if you are interested, I can take some pics and some measurements, but they will be in millimeters instead of inches
. Let me know. And for the grill cloth, I used Zich cloth
Best regards from France.
Pascal
Best regards from France