I spent 10 hours driving around a John Deere 544 I forget the model might be 05 and maybe k . Anyways when you step on the gas pedal the loader arms go up faster and if you pop it in neutral the bucket will drop faster while revving up the engine. Are there any loaders where you can keep a constant speed moving forward or backwards but have more flow or hydraulic power the further you push the joystick?
I thought they were all like that. Any loader I have ever driven moves the boom and bucket faster the farther you move the controls. With the boom up at an idle, I can lower it fast or slow. We do have an L45G Volvo. It is a hydrostatic drive. You can set the engine speed, set your ground speed, and control the flow for your auxiliary hydraulics.
More RPM equals faster hydraulics but the valve spools still regulate the speed. The more you push it, the more flow. A lot of machines when you step on a brake it gives priority to the implement hydraulics and disconnects power to the drive train so the hydraulics are faster. A lot of backhoe loaders have a button or foot pedal to give priority to the implement hydraulics.
Hydraulics pumps for implements or material handling usually Engine driven and are engine speed dependent. Only machines I know are not are variable ratio drive equipped where that is a expensive option.
Not sure if this counts for what is being asked but I'm attaching the Systems Operation of the implement pump for a 988H. Basically a two speed axial piston pump.