Quite a bit. Before and during the early years of the war, the German armaments industry was very fragmented and uncoordinated. The military had a great deal of control over it, but they were not suited for it. As was so typical of Nazi Germany, there were also a number of other factions playing politics and vying for control. There was also a tradition of carefully craft built weapons, which the military liked, ignoring the virtues of true mass production and sheer quantity. German weapons had beautiful craftsmanship, but they weren't producing anywhere as many as they could.

Hitler put Speer in charge of armaments production in 1942, and gave him an unusual amount of power. Some claim that Hitler liked the fragmented nature of power in Nazi Germany, and the infighting, because it was hard to organize against his power. Others say it was just bad management. Nevertheless in Speer's case he was given power to control pretty much the whole industry, and step on toes as needed. The effect was dramatic. War production continued to increase almost until the end of the war, despite things like strategic bombing. Mass production techniques were adopted, petty fiefdoms destroyed, and a centralized approach to planning instituted. Before anyone says that "central planning doesn't work", remember that US war production was also centrally planned, under the auspices of the War Production Board. I'm not taking a position on central planning under other circumstances, but for the duration it worked quite well in a number of countries.

In the US companies were told more what to do than how to do it, and there was quite a bit of innovation. This differs from what people may think of as central planning. Interestingly, and contrary to stereotype, that approach was also used in the USSR, whose ability to produce materiel under the worst of circumstances was amazing. When Speer adopted it it worked equally well, so it seems like a winning formula.

Source: Richard Overy, "Why the Allies Won".