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Topping LA90 Review (Integrated Amplifier)

Rate this amplifier:

  • 1. Poor (headless panther)

    Votes: 27 4.9%
  • 2. Not terrible (postman panther)

    Votes: 37 6.7%
  • 3. Fine (happy panther)

    Votes: 140 25.3%
  • 4. Great (golfing panther)

    Votes: 349 63.1%

  • Total voters
    553

amirm

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This is a review and detailed measurements of the Topping LA90 integrated amplifier. It was sent to me by the company and costs US $800.
Topping LA90 Review Stereo Integrated Amplifier High Performance.jpg

I must say, this is one interesting industrial design. Everything oozes style despite the diminutive package. This aspect continues in the operation of the unit with the sound of the relays solidly clicking indicating something good is going to happen. :) Here is the side view:

Topping LA90 Review Side View Heatsink  Stereo Integrated Amplifier High Performance.jpg


While quite solid, you can pick it up with one hand. The small size is aided by a massive external switching power supply:
Topping LA90 Review Back Panel Class AB Stereo Integrated Amplifier High Performance.jpg


Here are its ratings:
Topping LA90 Power Supply Review Amplifier.jpg


Back to the unit, you can see three balanced inputs. Volume control can be bypassed although I did not do so for my testing. You can also operate LA90 in bridged mono mode. There is also 12 volt trigger.

There are to gain settings. One at 10 dB and another at 20 dB (nominal).

Topping LA90 Measurements
These are non-bridged mode measurements. Bridged setup follows this section. Let's start with our dashboard of 5 watts into 4 ohm in low gain mode:


Topping LA90 Measurements Low Gain Integrated Amplifier High Performance.png


I don't need to tell you that this is a stunning level of achievement. We have a power amplifier producing almost the same SINAD as a state of the art DAC! Using this number, LA90 grabs the top spot with ease with a nice gap to boot:

Best Stereo Amplifie Review.png


Here it is zoomed:
1650912603277.png

You might be thinking that it can only do so with low gain but that is not true. Even in high gain performance is spectacular:

Topping LA90 Measurements HIgh Gain Integrated Amplifier High Performance.png


It would still achieve top spot in our rankings and achieve full audible transparency.

Not only is distortion vanishingly low, so is noise level:
Topping LA90 Measurements SNR Low Gain Integrated Amplifier High Performance.png


Topping LA90 Measurements SNR High Gain Integrated Amplifier High Performance.png


Frequency response is flat and wide as expected:
Topping LA90 Measurements Low Gain Frequency Response Integrated Amplifier High Performance.png


Being class AB design, it has no load dependency.

Crosstalk is incredibly good although it loses a tiny bit relative to last champ of amplifiers:

Topping LA90 Measurements Low Gain Crosstalk Integrated Amplifier High Performance.png


Multitone test shows the very low distortion levels:

Topping LA90 Measurements Low Gain Multitone Integrated Amplifier High Performance.png


Let's see how much power we have:
Topping LA90 Measurements SNR Low Gain Power into 4 ohm Integrated Amplifier High Performance.png


So power is modest in non-bridged mode. But note how good the high gain mode is so I would feel just fine using that for operation of the unit if you need to. Allowing distortion to rise to 1% naturally gets us more power:

Topping LA90 Measurements SNR Max and Peak Power into 4 ohm Integrated Amplifier High Performa...png


Here is 8 ohm:

Topping LA90 Measurements SNR Power into 8 ohm Integrated Amplifier High Performance.png


Oops. "High Power" should be "High Gain."

Changing frequencies shows the same excellent performance:
Topping LA90 Measurements SNR Low Gain Frequency vs Distortion vs Power into 4 ohm Integrated ...png


Despite being pushed deep into clipping, the amplifier did not complain until I got to 20 Hz where its over temperature shut it down.

Finally, you don't need any warm up:
Topping LA90 Measurements Warm up  Integrated Amplifier High Performance.png


Topping LA90 Bridged Mode Performance
A shorting wire is provided to connect the two negative speaker bindings together allowing bridged mode from the top two posts. Here is our dashboard again:

Topping LA90 Measurements Bridged 8 ohm Integrated Amplifier High Performance.png


Performance is still exceptional. Here is our SNR:
Topping LA90 Measurements Bridged 8 ohm SNR Integrated Amplifier High Performance.png


Due to more power available now, we cross the amazing 140 dB SNR threshold. What this says is that even if you play at 140 dB, the noise level will be at or below threshold of hearing! Of course there is not enough power there to do that but basically you know that noise is not part of the equation with LA90 as even 5 watt measurement hits below threshold of hearing.

We want to know the power increase though so here it is (with 8 ohm which is the minimum impedance):
Topping LA90 Measurements Bridged Power 8 ohm Integrated Amplifier High Performance.png


Now we get good bit of power at 95 watts with almost no penalty relative to non-bridged mode. Notice the massive gap as far as noise floor relative to Purifi amplifier.

Allowing for 1% distortion we get:
Topping LA90 Measurements Bridged Max and Burst Power 8 ohm Integrated Amplifier High Performa...png


Here is the super wideband spectrum of the amplifier while producing 5 watts:

Topping LA90 Measurements Bridged FFT 8 ohm Integrated Amplifier High Performance.png


Edit:
Power Tests at 2 Ohm (Stereo) and 4 Ohm (Bridged)

Requests were made to test the amplifier beyond its minimum load impedance specs. Let's start with 2 ohm load while driving one channel in stereo mode. Dashboard still shows superb performance:

Topping LA90 Measurements 2 ohm Integrated Amplifier High Performance.png


Let's now sweep the power:
Topping LA90 Measurements 2 ohm Power sweep  Integrated Amplifier High Performance.png


You don't get extra power relative to 4 ohm but the amplifier was stable and did not even go into protection.

Now let's switch to Bridged mode (both amplifiers driven in differential mono) and run our power sweep again:
Topping LA90 Measurements 4 ohm Bridged Power sweep  Integrated Amplifier High Performance.png


Now we see the amplifier "doubling down" producing nearly 200 watts into 4 ohm. Again, the amplifier was well composed and kept driving into clipping region without complaining, or shutting down.

Again, the above tests are beyond the amplifier specifications and tests I never run as such.

Conclusions
It is clear that Topping engineers are bringing their expertise in designing ultra low noise and distortion in headphone amplification to power amplifiers. As such, they have outdone every amplifier I have measured in that regard, getting ahead to capture the #1 position with a large gap to #2 choice.

The amplifier is not for everyone though. Power level is modest as compared to competitors. And you have that large external power supply. My wish is another version of this amp with built-in power supply, motorized volume control with bridge mode standard. For now, we need to celebrate one of the most important development in delivering transparent, high fidelity amplification to audiophiles in a very attractive package.

It is my absolute pleasure to recommend the Topping LA90. History is made on this day folks!

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As always, questions, comments, recommendations, etc. are welcome.

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aravena562

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Difficult use case due to the low power, in bridge mode it is already more usable, but the price is already high, at the purifi level or more, and if you use all the power it ends up having the same THD, it is only better at levels lower than 95watts.
I still feel tempted...
 

BoredErica

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I feel like for the cost the power output is too low.And I think the amp looks very uninspired with the grey monotone look. Gain switch is nice to have though more options than just 10 and 20 would be better. Maybe a 15 and 25?

If 2ohm is too low can't we split difference and do 3ohm?
 

sq225917

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Given that noise and distortion isn't an issue on any of the top 15 amps tested I'm wondering what the point of it is? How big is the market for modestly powered ultra-fi?

I guess we're about to find out.
 

MRC01

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As this is an integrated amp, tell us more about the volume control. You said lots of relays clicking - does the volume control use relays to change resistors in the gain-feedback loop? Or is it a conventional pot? How does the SNR change with volume control, like when you turn it down to some reasonable level like -20 dB?
 

raest

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considering the power, i wouldn't buy this even at half the price. this is waaaaay too close to Purifi amps which have boatloads more (and more than "clean enough") power and shouldn't have any problems driving any kind of load... not to mention being Class D they're significantly more efficient. this looks like an amp designed to be sold purely based on SINAD
 

restorer-john

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A shorting wire is provided to connect the two negative speaker bindings together allowing bridged mode from the top two posts.

This (above) combined with the power supply that appears to be single rail ([email protected]), suggests the amplifier is already running in bridge mode when operated in stereo.

Switching to mono creates a bridged, bridge amplifier. It is highly likely this amplifier will have trouble with impedances below 4R in mono. Their spec also says 8R is the minimum in mono mode.
 

TheBatsEar

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Will you look at that, my speakers lowest impedance is 6 ohms :cool: And as an apartment dweller this would play loud enough.

I could get one and just add an annoyingly smug "Yes, but your SINAD measurements are rookie numbers, friendo" under any amp thread.
 

TheBatsEar

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I wonder how you switch sources. If the volume knob a button too?

Edit #1: As answered by many: The power knob also switches the source. :cool:
 
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