This is a review and detailed measurements of the new Topping L30 headphone amplifier. It is a companion to their E30 DAC. I don't have official pricing on it but see it on some sites for US $130.
EDIT: I have learned that a few members have had their headphones damaged due to failure of the L30 headphone amplifier. Topping is aware of this and is trying to investigate. These could be isolated experiences and hopefully they are. If not, I wanted members to know about this potential issue.
Edit2: As far as I know, the above was resolved by Topping.
This is a compact unit but with nicely thought out controls:
There was a plastic cover in the front which had very clear labels on it. But once I pulled it off, I realized the real labels are not as easy to read. So you may want to leave that plastic on it. Then again there is not much to remember here to need the labels. The left switch controls whether the output is the headphone or line out in the back. And there are three useful gain modes: -9, 0 and +9 dB. The first one is super useful for very sensitive IEMs and headphones allowing the volume control to operate in its most accurate range.
The back panel is as you expect but there is a change in how the unit is powered:
Yes, it is a rather heavy, 15 volt AC transformer rated at 1 amp. Not a switching power supply. So be careful to get the unit rated for your country. AC transformers have a design benefit in that you can create both positive and negative DC supplies from them which is needed for amplification. With a single voltage switching power supply, you have to create a negative supply using DC to DC switching converters that creates a weak link.
In use, the L30 got a bit warm but nothing to be concerned about.
Headphone Amplifier Audio Measurements
As usual, I feed the amp a superbly high quality analog 1 kHz tone at 2 volts, set the volume/gain to output 2 volts ("unity gain") and see how much distortion and noise we get:
Wow, this is incredible. You can barely see a distortion spike at -150 dB, some of which is from the analyzer output. SINAD which is the some of noise and distortion, is now dominated by the noise of L30 and the analyzer itself, producing near limit of 121.4 dB. This lets the the L30 to reach the top of the ladder by a hair:
Quite an accomplishment!
Noise performance by itself is excellent:
The right side shows that even when we drastically reduce output to just 50 millivolts, we still have the full dynamic range of the CD, placing the L30 again at the top of the class:
Frequency response of course is exceptionally flat and wideband:
Multitone test resembling "music" proves how clean this amplifier is:
Most important test here is power so let's see what the L30 can do into 300 ohm (high) load:
Wow! There was a time when we thought the Drop THX AAA was the best we could do and here comes the L30, with so much lower noise and distortion. Note that this test for historical reasons does NOT use the lowest distortion mode of my analyzer. So actual distortion is limited by this test setup. The L30 is likely even better than what is seen.
Same beautiful dance is shown with opposite load of 33 ohm:
Channel balance was exceptionally good for an amplifier with analog controls:
If the other samples in the field are this good, this alone differentiates the L30 strongly from the competition for those of you with sensitive IEMs/headphones.
Headphone Amplifier Listening Tests
Measurements predicts that we have tons of absolutely clean power and that is what I heard. Even with my low impedance and very inefficient Ether CX headphone, I had no trouble getting clean sound to the limits of what I could tolerate. Ditto for HD-650 which produced exceptional detail and thundering bass which it can only deliver when pumped with authority.
Conclusions
The race toward perfection and beyond continues in headphone amplifiers at incredibly low prices. The L30 is the latest offering, firmly grabbing the top of the class and holding on to it. Its functionality is excellent and price is very reasonable.
I can't recommend the Topping L30 strongly enough. It is superb engineering in small package and low cost. Get one and thank yourself that you live in this era and not a few years ago.
-----------
As always, questions, comments, recommendations, etc. are welcome.
Here it is Sunday evening and I am "working" doing reviews. Least you all can do is pay me well by
donate what you can using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
EDIT: I have learned that a few members have had their headphones damaged due to failure of the L30 headphone amplifier. Topping is aware of this and is trying to investigate. These could be isolated experiences and hopefully they are. If not, I wanted members to know about this potential issue.
Edit2: As far as I know, the above was resolved by Topping.
This is a compact unit but with nicely thought out controls:
There was a plastic cover in the front which had very clear labels on it. But once I pulled it off, I realized the real labels are not as easy to read. So you may want to leave that plastic on it. Then again there is not much to remember here to need the labels. The left switch controls whether the output is the headphone or line out in the back. And there are three useful gain modes: -9, 0 and +9 dB. The first one is super useful for very sensitive IEMs and headphones allowing the volume control to operate in its most accurate range.
The back panel is as you expect but there is a change in how the unit is powered:
Yes, it is a rather heavy, 15 volt AC transformer rated at 1 amp. Not a switching power supply. So be careful to get the unit rated for your country. AC transformers have a design benefit in that you can create both positive and negative DC supplies from them which is needed for amplification. With a single voltage switching power supply, you have to create a negative supply using DC to DC switching converters that creates a weak link.
In use, the L30 got a bit warm but nothing to be concerned about.
Headphone Amplifier Audio Measurements
As usual, I feed the amp a superbly high quality analog 1 kHz tone at 2 volts, set the volume/gain to output 2 volts ("unity gain") and see how much distortion and noise we get:
Wow, this is incredible. You can barely see a distortion spike at -150 dB, some of which is from the analyzer output. SINAD which is the some of noise and distortion, is now dominated by the noise of L30 and the analyzer itself, producing near limit of 121.4 dB. This lets the the L30 to reach the top of the ladder by a hair:
Quite an accomplishment!
Noise performance by itself is excellent:
The right side shows that even when we drastically reduce output to just 50 millivolts, we still have the full dynamic range of the CD, placing the L30 again at the top of the class:
Frequency response of course is exceptionally flat and wideband:
Multitone test resembling "music" proves how clean this amplifier is:
Most important test here is power so let's see what the L30 can do into 300 ohm (high) load:
Wow! There was a time when we thought the Drop THX AAA was the best we could do and here comes the L30, with so much lower noise and distortion. Note that this test for historical reasons does NOT use the lowest distortion mode of my analyzer. So actual distortion is limited by this test setup. The L30 is likely even better than what is seen.
Same beautiful dance is shown with opposite load of 33 ohm:
Channel balance was exceptionally good for an amplifier with analog controls:
If the other samples in the field are this good, this alone differentiates the L30 strongly from the competition for those of you with sensitive IEMs/headphones.
Headphone Amplifier Listening Tests
Measurements predicts that we have tons of absolutely clean power and that is what I heard. Even with my low impedance and very inefficient Ether CX headphone, I had no trouble getting clean sound to the limits of what I could tolerate. Ditto for HD-650 which produced exceptional detail and thundering bass which it can only deliver when pumped with authority.
Conclusions
The race toward perfection and beyond continues in headphone amplifiers at incredibly low prices. The L30 is the latest offering, firmly grabbing the top of the class and holding on to it. Its functionality is excellent and price is very reasonable.
I can't recommend the Topping L30 strongly enough. It is superb engineering in small package and low cost. Get one and thank yourself that you live in this era and not a few years ago.
-----------
As always, questions, comments, recommendations, etc. are welcome.
Here it is Sunday evening and I am "working" doing reviews. Least you all can do is pay me well by
donate what you can using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
Last edited:
