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Class AB amplifier for measuring on a PWT

Elysio

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Jan 1, 2025
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Hi community.

I have a special request.
I am searching for a class AB amp with very low K2 and K3.
I want to use it as a measuring amplifier on a PWT , plane wave tube.
Now I am using the Aiyima A70, which is a good amplifier. But it has one major drawback.
It is a class D amp and with that I can not use it for impedance tests or any other test where
It can accidentally happen touching ground and the equipment
will blow up, because the class D amp is floating. I.g. like a voltmeter with ground etc...
Is there a affordable class AB amplifier with very good noise and distortion values ?
A short information for the purpose. I am measuring compression driver on the plane wave tube.
I am developing those compression driver and to get a more accurate feedback of my developments
I have to measure K2 and K3 distortions. For that it is important to have a amplifier with ultra low
distortions.
 

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They are using the LM 3668 chip. How can they reach such low distortion values if the chip itself dies not offer such low distortion values ? Strange, isn't it ?
 
The Modulus series amps are composite designs. See thread at DIY Audio for more info.
 
There are two ways to build a measuring amp: Buy ready made and very expensive or DIYS and save on money, but pay with a little time.
If you don't know how to DIYS, you may get help in some so called DIYS HIFI forums.
The basic -86 Neurochrome amp will fit your needs.
 
The Outlaw 2220 has low distortion. I don't know if it suits your needs overall but the distortion is slightly better than the Aiyima A70.
edit: now I see you did also say low noise in your OP. The outlaw might night have low enough noise for you.
 
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