Hi Cradeldorf and thanks for your reply,
Actually i was on the point to try to send you a mail when i saw your post.Unfortunately,the pictures of the drivers show that the LF cones should be changed.I know it is a pity but i am affraid there is no other solution.Actually,i paid both drivers a little bit more than 400 USD so i cannot expect miracles .I guess the HF diaphrams may have to be changed as well.Bill will tell me.Regarding the horns,they have been shortened at the mouth level by 0.5 to 1 cm.I speculate that this was done because the previous users were front mounting the speakers and trying to make sure that the front of the mouth do not touch the protective grille.Apparently GPA have an original pair of cross sectionnal horns(the one used on the C,D,E,G...models).I guess after restoration,they should be fine.I will ask Bill to use the low handling power diaphragms,cones and the lightest available moving mass.
I was very interested in your comments regarding your 604 C.With crossover are you using,a stock 1600 X over or another one .What type and size of cabinets do you use?Since it is my first Altec project i am looking for guidance.Yours will be appreciated.Did you finally buy the beautifull 604 D,paper surround which was on sale on the site?