Topping LA90 Discrete Amplifier Review

[mike7877]

L7Audiolab measured the volume knob's impact on the original LA90 at 5W/4Ω:
View attachment 365547 View attachment 365548
Source: https://www.l7audiolab.com/f/topping-la90/

Roughly the same impact can be expected with the LA90D.

Nice.

Check this out:

50mV -83dB THD+n

SNR has to be higher than THD+n. In this case I don't know by how much, but for fun let's say the noise is at -87dB compared to signal - puts it pretty high up there in the ASR chart of headphone amps (best being 95 except for the L30 II)... We already know the thing sounds good- at this point, might as well make a 2x speaker wire (terminated with banana plugs) to female 4 pin XLR connector and use the LA90(D) as a headphone amp! Comes complete with volume control lol

 

[Michal]

Does this amplifier have any operational amplifier in the signal path, or maybe it is a 100% discrete circuit from input to output?

 

[babadono]

Does this amplifier have any operational amplifier in the signal path, or maybe it is a 100% discrete circuit from input to output?

I would assume yes...but I sure want to take one apart. Don't think we will ever know what is in the black encased modules. Just received a 9" 2mm T handle hex key for this very purpose.