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XLR input impedance of Topping LA90/LA90d power amp is higher than its recommended preamp Pre90?!

Kolatratar

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The input impedance of Topping LA90/LA90discrete balanced input is 20kOhms:


The input impedance of the Topping Pre90 balanced input is 2kOhms:

I just purchased a Topping LA90 discrete. I'm quite impressed with its sound quality and I am considering the Pre90 - Topping's website recommends the LA90d to be paired with the Pre90 preamp.

However, the input impedance of the LA90d is 20kOhms while that of the Pre90 is 2kOhms!

Does anyone find it really strange that the input impedance of the preamp is lower than that of its power amp?! What's the point of having a preamp then?
 
The input impedance of Topping LA90/LA90discrete balanced input is 20kOhms:


The input impedance of the Topping Pre90 balanced input is 2kOhms:

I just purchased a Topping LA90 discrete. I'm quite impressed with its sound quality and I am considering the Pre90 - Topping's website recommends the LA90d to be paired with the Pre90 preamp.

However, the input impedance of the LA90d is 20kOhms while that of the Pre90 is 2kOhms!

Does anyone find it really strange that the input impedance of the preamp is lower than that of its power amp?! What's the point of having a preamp then?
Volume control, input selection. It's the output impedance of the pre90/input of the la90 you need to look at.
 
Volume control, input selection. It's the output impedance of the pre90/input of the la90 you need to look at.
And the Pre90 input impedance to make sure that whatever sources you plug into it are comfortable at 2k load impedance.
Many vintage electronics may not be.
 
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