Here is a good way to upgrade that pair of screw type output binding posts on your original Dynaco ST-70... These upgraded VTA gold plated PAIR of output binding posts will fit any original Dynaco ST-70. The RED post may be set up for 4 or 8 or 16 ohm speakers. These binding posts may use speaker wires that terminate with either bare wire up to 12 gauge (which fits into the hole on the outer post), or spade lugs or banana plugs. Unsolder all the wires from the original screw terminal board and then remove the original Dynaco screw terminal board. Dissasemble the posts from the new backing board and then place the backing board on the INSIDE of the amp and secure the new board with the new screws and nuts provided. Place the RED post on the side that says "8 16" and the BLACK post on the side that says "G" on the rear face of the amp. Then tighten the nuts making sure that hole in the outer post faces UP. Inside your Dynaco ST-70 amp the BROWN wire is the 4 ohm wire, the ORANGE wire is the 8 ohm wire and the YELLOW wire is the 16 ohm wire. According to the impedance of your speaker, just connect the wire you want to the red binding post and the BLACK wire that now connects to the "G" screw to the BLACK binding post. You can place the wire under the nuts that hold the post on OR solder the wire to the knurled end of the post. FREE shipping to the USA ...