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WolfX700 Measurement of Topping L30 Headphone Amp

WolfX-700

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#1
In fact, this (pre-production) machine has been here for a long time, and the completion degree is very high when I get it (I gave some unimportant suggestions). Later, in order to keep improving, the manufacturer made some adjustments to the power adapter. Last week I got the final retail version of the external power adapter. The basic measurement data has not changed, but the power (current output capability of the device) at 16R has been more liberated!

In my opinion, this is a game-changing amp. Out of respect for developers and manufacturers, I have always insisted on their authorization to release the measurement results.

The manufacturer gave me the authority to release the measurement this week.

So, here comes (the measurement is incomplete, because I am too busy as a teacher at the end of the semester, and I will add the rest tomorrow evening. Forgive me)

Photo.jpg

Rear.jpg


In terms of appearance, considering the price (slightly more than 100 dollars? They didn't tell me the specific price), there are very few places that can be picky. And... For the measurement results of this device, the appearance is completely unimportant!

Measurement result:

4V Dashboard
Dashboard.jpg

The crazy 122SINAD! 0.00007X%THD+N!


I adjusted the level to 5V to get the best result of AP:

5V.jpg

OK 124……

This is close to AP's Loopback (except for some interference caused by wiring?)

loopback.jpg

In this measurement, L30 is close to (except for some more noise caused by wiring etc.) the analog measurement limit of APx555!

Dynamic-Range.jpg

Due to the noise floor of the AP itself, the DNR at 50mv can only be measured to around 95db. If this measurement reaches 95db, I will use a 40db low-noise amplifier to simultaneously amplify the noise floor and distortion of the device (in fact, it will deteriorate the measurement result)


THD+N-Ratio-vs-Measured-Level-16R.jpg

THD+N-Ratio-vs-Measured-Level-32R.jpg

THD+N-Ratio-vs-Measured-Level-50R.jpg



Relative-Level-(1.00000-kHz).jpg

THD+N-Ratio-@4.jpg


THD+N-Ratio2.jpg

SMPTE-Ratio.jpg




Multitone:
Multitone.jpg

Already close to AP's own generator... performance limitations?

The channel balance... barely makes sense... I will update the data of other units.

RMS-Level.jpg


Crosstalk
Crosstalk.jpg


OI.jpg
 
Last edited:
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#2
Thanks @WolfX-700 cant wait to see the rest of the numbers.
 

Vini darko

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#4
Crazy town numbers. Can't wait to thow money at Topping. Thankyou wolf look forward to the rest of the measuments.
 

Vini darko

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#5
What's the smpte graph? I have a rough grasp of the others but have no idea what that ones measuring.
 

CASE2112

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#6
Can we get a pic of the back?
 
OP
WolfX-700

WolfX-700

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Thread Starter #12
Can we get a pic of the back?
Please wait a few hours... I'm already in bed

Wolf, you fail with the measurements. You've measured your AP analyser instead the Topping unit.It's to much for around 100$, hard to believe. Are you sure it's not a golden sample?
I have strictly warned the producers not to send me golden sample. I will soon have a second device for cross-validation - and, considering that it is very, very cheap, I will secretly sample from the market using channels unknown to the manufacturer.

If there is a significant deviation in any sampled unit-I will give the report and serial number.
 

3125b

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#15
Cool, finally a (very) good and hopefully budget headphone amp thats coming to the European market!
At around 150€ this is gonna be a great deal I imagine.
 

Human Bass

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#17
Damn, now we need updates on the A50S so i can decide the bal out is worthy,cause the L30 is already budget perfection.
 

odyo

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#18
Can we have measurements of different gain levels and 50mv for super sensitive headphones as well ? Waiting for the second part. This product gonna be popular.
 

JohnYang1997

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#19
Can we have measurements of different gain levels and 50mv for super sensitive headphones as well ? Waiting for the second part. This product gonna be popular.
Same for low and mid settings. Reduced noise performance for high gain(still better than the competition).
 
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#20
@WolfX-700 @JohnYang1997 I’m not really familiar with reading graphs, but isn’t there a conflict with the graph for the 50R load? I get that the 3.2W figure came from the X Axis under the Cursors, but the graph itself shows something more like 1.7W at a 50R load.
 
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