Just a little information for those of you who own these classic speakers and wonder why the foam surrounds are usually bad . There were 2 versions -The fist and original cat# 4024 had rubber surrounds, screw terminals, 10 screws in the L-pad plate, 8 ohm woofers and dual wound brass voice coils

The latter vesrions Cat # 4029 had the (known rotter) foam surround, clip terminals, 6 screws in the L-pad plate, and 4 ohm woofers this version also is the muddy whompy sounding machs that were released after 81' There are no comparison to the sound of the two different verions so beware of this verion on Ebay ect..they are junk .

The Original 4024's were manufactured by Thompson Electronics for Tandy from 77 to 81' the 4029's were made by Optimus from 82 to 84' and they were produced much cheaper to hold a changing market

If anyone has not experienced the original line of the Mach Ones (4024) you should take a listen the quailty of sound is unbelievable compared to todays market of speakers