Specifications

16
Intelligent Rail Voltage Control
High current or low current? How can you have one amp do it all?
With conventional designs you can’t. As impedance goes down, the amount
of current needed goes up and the required voltage goes down. So, with
most 4 Ohm amps, if you hook up too low a speaker load, the amp will pour
so much current into it’s components that it will simply burn itself up or go
into protection. Others have sold amps to play a variety of loads, but they
have used systems of Automatic Gain Control. They simply attenuate the
input signal when impedance goes down. This tends to add distortion and it
decreases efficiency.
Example: One company’s 500 watt Class D amp plays at most any
load, but it’s efficiency is exactly the same as the ZAPCO 500 watt class A/B
amplifier. The same is true of their 1000 watt D and ZAPCO’s 1100 watt
A/B. So, it plays most loads but it sacrifices the only advantage of Class D
amps...efficiency. You sacrifice both sound quality and efficiency to be able
to use any speaker.
Question: How do you get the advantage of a wide range of loads without
sacrificing efficiency or adding distortion?
Answer: The new ZAPCO, Intelligent Rail Voltage Control system™
(IRVC).
ZAPCO’s IRVC uses a discrete component circuit at the output
stage which constantly monitors the current requirements of the amplifier
stage. This circuit then adjusts the rail voltage so that the amplifier stage is
always operating at peak efficiency. If the load is consistently below ideal,
the circuit illuminates the Low-Z light. This prompts you to switch the entire
unit into the “Low-Z” mode.
This Low-Z mode adjusts the power supply itself to maximize
efficiency at the lowest impedances.
So here you have the best solution. ZAPCO’s IRVC circuit lets you
play virtually any speaker load, and still lets your amplifier stage operate at
peak efficiency, with minimum distortion.
Wow! It’s like more power and better mileage. You don’t have to choose.