Because ribbon tweeters (I guess by extention any planar speaker) inherently have better transient response than mose speakers, would they benefit from higher slew rates?
Amplifier slew rates are at least 5x higher than needed to reproduce a 20KHz sine wave at full power. This is to avoid slew-rate distortion.
Music has very little high-frequency energy.
If you are considering Magnepans, the most important amplifier attributes are the ability to drive 4 ohms and a low output impedance.
Ed
Music has very little high-frequency energy.
If you are considering Magnepans, the most important amplifier attributes are the ability to drive 4 ohms and a low output impedance.
Ed
Actually I recently acquired a set of RAAL 70-20s from another member here (shoutout to @studiotech ) and am going to drive them actively. Just while surfing the web I started to look at electrostatic headphone amplifiers and noticed one had the lme49600 in the output stage. Just got me thinking since I'm using a diaphragm with much higher transient response than your typical cone that a higher slew rate would be beneficial.
As an aside I got a chance to try a set of magnepans a little while ago. They're delightful plain and simple. The shocking part is they actually have a set for only 1k. That's bonkers lol
The LME49600 is fast so that it can be used inside a feedback loop. The op-amp driving it has a slew rate of 20V/uS.
Ed
Ed
I'm not sure I follow. Is slew rate a particularly desirable thing in feedback loops? I thought it was only specifically for the speed of the amplifier itself? Or do you mean like a composite configuration?
In the headphone amplifier in LME49600 datasheet figure 28, the overall slew rate is set by the op-amp.
Slew rate is a consequence of a constant current source charging a capacitor. The capacitor's purpose is frequency compensation.
Ed
Slew rate is a consequence of a constant current source charging a capacitor. The capacitor's purpose is frequency compensation.
Ed
Ah I see. So if high slew rate is so beneficial, why is it not used more often? I usually only see really high slew rate in things like RF and instrumentation. That's why I was surprised by the LME49600
Ah OK so it's only more beneficial at that scale because the voltages you're working with are so small.
Thanks for all the info Ed. Much obliged 🙂