The toast at this setting will always be the same color because the toaster uses a compensating thermostat. Depending on the setting, the compensating thermostat will be used to regulate the heat settings at different amounts of time. In one setting, the compensating thermostat could go on for much longer than the other setting before shutting off.
The density would increase because you still have the same amount of weight, but it is just packed more tightly in a smaller object.
