Topping L50 Review (Headphone Amp)

[frogmeat69]

A DAC with XLR to SP200 should solve noise issue. Schiit Modius (maybe look used market too?) or sure, SU-9 will be good.

Or the Topping D10 Balanced.

 

[MattISO]

Based on these measurements, I should be able input 4 Volts Balanced from a DAC INTO the L50 and get 5 Volts / 1.25 Watts Balanced OUT into a 20 Ohm load in High Gain without audible noise or distortion right?

 

[kchap]

Based on these measurements, I should be able input 4 Volts Balanced from a DAC INTO the L50 and get 5 Volts / 1.25 Watts Balanced OUT into a 20 Ohm load in High Gain without audible noise or distortion right?

Yes.

 

[MattISO]

Yes.

Another question, even though the output voltage of the DAC (4 Vrms) is greater than the input sensitivity of the amp (2.7 Vrms), the audio will only clip or distort in high gain if I exceed 7 Vrms right?

 

[kchap]

Another question, even though the output voltage of the DAC (4 Vrms) is greater than the input sensitivity of the amp (2.7 Vrms), the audio will only clip or distort in high gain if I exceed 7 Vrms right?

To be safe say it's 7 Vpp which is just a tad under 2.5 Vrms. If you are worried about over driving the amp you can switch to the medium gain. I've got one along with the E50 DAC, it sounds great. Of course they all do but, in combination with a good DAC such as the 50E you will not hear any noise.

I should lay my cards on the table at this point; I know own a RME ADI-2 DAC/Headphone amp. I prefer the RME over the E50/L50. It's nothing to do with superior sound. To me both the RME and the topping combo sound the same and because it's the more recent design, the L50 may have the better specs.

I just like the user interface on the RME I'll be the first to admit it's hard to justify paying twice the the price of the E50/50L for nicer knobs and a better menu, so I won't. Well it was on special, it's normally two and a half times the price!

 

[MattISO]

To be safe say it's 7 Vpp which is just a tad under 2.5 Vrms. If you are worried about over driving the amp you can switch to the medium gain. I've got one along with the E50 DAC, it sounds great. Of course they all do but, in combination with a good DAC such as the 50E you will not hear any noise.

I should lay my cards on the table at this point; I know own a RME ADI-2 DAC/Headphone amp. I prefer the RME over the E50/L50. It's nothing to do with superior sound. To me both the RME and the topping combo sound the same and because it's the more recent design, the L50 may have the better specs.

I just like the user interface on the RME I'll be the first to admit it's hard to justify paying twice the the price of the E50/50L for nicer knobs and a better menu, so I won't. Well it was on special, it's normally two and a half times the price!

O Ok Thank You very much for the reply.

 

[welder]

When driving Hifiman HE400SE, with High gain setting and passing 3/4 of volume pot rotation, after second of two Topping L50 is shutting down, and LED status diode is blinking instead of being constantly lit. Then I need wait some time for it to get back to life, no matter whether I replug power to unit or not.

My uderstanding is that there is some kind of protection circuitry kicking in?


PS. This is by any means how I am listening to music, rather testing whether they can be a loudspeakers

 

[kchap]

When driving Hifiman HE400SE, with High gain setting and passing 3/4 of volume pot rotation, after second of two Topping L50 is shutting down, and LED status diode is blinking instead of being constantly lit. Then I need wait some time for it to get back to life, no matter whether I replug power to unit or not.

My uderstanding is that there is some kind of protection circutry kicking in?


PS. This is by any means how I am listening to music, rather testing whether they can be a loudspeakers

What is the signal source for the L50? Maybe it needs to be in the medium gain mode.

 

[welder]

What is the signal source for the L50? Maybe it needs to be in the medium gain mode.

Topping E50 through balanced.
Dont get me wrong, I know that I am pushing it far beyond regular listening levels. For listening I am using mid gain and volume pot around 12 o'clock.

My only question is whether should I worry that there is something wrong as unit should work all the way to the end of volume pot scale or its just matter of internal protection of unit itself (hot balanced input + high gain + low impedance/moderate efficiency headphones).

 

[Vini darko]

Topping E50 through balanced.
Dont get me wrong, I know that I am pushing it far beyond regular listening levels. For listening I am using mid gain and volume pot around 12 o'clock.

My only question is whether should I worry that there is something wrong as unit should work all the way to the end of volume pot scale or its just matter of internal protection of unit itself (hot balanced input + high gain + low impedance/moderate efficiency headphones).

I think you're pushing about 2.5 watts into them. So the l50 is hitting clipping and thermal overload. Probably best to back off before either the amp or headphone gets damaged.

 

[kchap]

Topping E50 through balanced.
Dont get me wrong, I know that I am pushing it far beyond regular listening levels. For listening I am using mid gain and volume pot around 12 o'clock.

My only question is whether should I worry that there is something wrong as unit should work all the way to the end of volume pot scale or its just matter of internal protection of unit itself (hot balanced input + high gain + low impedance/moderate efficiency headphones).

If the Head Phones were a straight resistive load the protection should not kick in but, it will be a reactive load which is harder for the amp to deal with. It is also likely the headphones are being driven into a non linear region which will reduce the impedance and increase the current.

Not only is the protection mechanism protecting the amp it is probably doing your headphones a favour as well.

 

[Max_74]

..And here it is : naked , note , on the bottom a leaf of insulating plastic between the board and the chassis .
(my L30 died , op amp near power chips burnt , Sundara safe for a "Miracle" , buzzing sound after switching from hi gain to med gain ... the volume was set quite low while I was listening....

Blinking led " ïssue ", happened twice , seems L50 do not like been powered off from a switch before the transformer. (Safety mesure John Young? ) ...may be related to relay setting logic , bypass etc.

Shenzen audio offered to repair the unit but I will have to pay for the shipping ... at that point , the board was bulging on the bottom (opposite to the opa .. an smd cap burnt out too , the opa exploded burning in short ......

Repair what?...

To be clear shenzen offered a substitution to a batch of L30 known to be prone to the issue i've described , mine is older referred to that batch ... the lemon still smell , i mean really , 4 days off , air passed but the stink in my room is still slightly disturbing ... may be i've had to leave closed the device .

 

[cheapmessiah]

I just bought a refurbished L50 from a local store, what should I look for as signs of future problems with it so I can decide if I keep it or if I return it?

Forget about it, the order was canceled since they cant find the package at their storage facility.

 

[Bel Canto]

Question regarding gain settings on this amp. Would it be better to run medium gain at 2 o'clock or high gain at 10 o'clock?

 

[Max_74]

Question regarding gain settings on this amp. Would it be better to run medium gain at 2 o'clock or high gain at 10 o'clock?

at 2 U"ll have better L/R matching , even if 10 is (on my unit ) yet OK ... the sound is different , hi gain (i suppose) uses an op amp to amplify the signal .. on mid not , neither on low , just added resistors before the volume potentiometer , so (theoretically) mid is better , but judge Yourself what do U prefer.

 

[Max_74]

Ehmmmm ..... actually blinking led on L50 means , as the manual indicate " Blink to indicate unexpected output " ....
Come on Topping , an other issue? do i have to return to Amazon with the chance to have an other one with identical problem? ??? U provided a programming port (usb c) and John Young said "hopefully not to use"...
Firmware update please Topping , C'Mon!!!
Sound good the L50 , and compared to L30 "sadly blown" I feel it a tad softer , more round sounding and a better less compressed in dimension sound stage , but just a tad all of that .
I did't needed more power or "balanced" out and Input , just to stay away from L30 , sadly , i really enjoyed that .
Errrr same transformer and couple of 4700uF elcond as L30 , Double power?
The chassis is double thick and the increased surface of the device led to just 10- 11 degree celsius more referred to ambient , a step up compared to L30 16-17 degree C...
So : a week and I'll decide what to do with substitution or refund ... But Damn it sound quite (actually quite a lot) good .........
for reference tested with sundara , k361 , dt770 80 ohms , hd560s ... both un equalized ad eq'ed .
If helped someone , i'll be happy.

 

[JGeez]

The blinking light occurs if you turn off your system while the L50 is on. Turn off the L50 off first before you turn off the rest of the system. Then when you start up again, it won't happen. At least this was my experience with the L50.

 

[Max_74]

The blinking light occurs if you turn off your system while the L50 is on. Turn off the L50 off first before you turn off the rest of the system. Then when you start up again, it won't happen. At least this was my experience with the L50.

I'll see in a week what"s what , however , even if it happened (flashing) even if I did like U suggest , today all is working properly .
For now I'm pretty confident I'll keep the amp , still "opening up" the sound , it needs to play a lot (it's working , someone laughed at the term "burn in" ) different type of music , different volumes , different headphones ....
It's superior compared to L30 , or , I like more the sound signature , but still miss L30 (with an year and a half of life , seem L30 was more transparent , sound stage li'l compressed but more (slightly) trasparent .
How ever now i shitch on the external transformer before the unit , whait say 3-4 sec , and all is ok .
(please note , when the amp is warm i can switch on and off the way i prefer (the system) , no flashing light , never ) .

...a safety measure ALWAYS WAIT 10 SECOND , WHEN U SWITCH ON - OFF -ON audio gears (rectifier , transformer an electrolytic caps work with very HI currents and go HOT and HOTTER .... (plus digital equip needs some time to reset "logic") . ALL ARE WARNED .
a technician (i'm not an engineer) advice .

 

[Indrajit]

Hi. Does the L50 have identical power output if it is used in pure single ended configuration (rca input + single ended output) compared to its (XLR input) setting. I have a Topping E30 and a Magni 3 and I am looking for an amp for more power via (single ended input + single ended output) for my Sennheiser hd 650. I am planning to buy L50 but I am concerned regrading any decrease in power output if it is used in (single ended input + single ended output) with a dac like E30. I don't really want to buy L30 as L50 has more power. So I would like to know what is real power output of L50 in (single ended input + single ended output) at 300 ohm load.

 

[Indrajit]

This is a review and detailed measurements of the new Topping L50 balanced (input) headphone amplifier. It was sent to me by the company and costs US $229. It will be announced shortly.

The industrial design of the L50 is different than older models with a plexiglass front:

View attachment 150530

While I like the red accent on the volume control knob, the contrast is low on the labels to read them easily. There is a plastic cover that has duplicate labels on it which are more legible. Fortunately there is not a whole lot here to remember as to need the labels.

The back side and power supply show more of a departure:
View attachment 150531

Instead of the usual switching power supply we now have a beefy AC transformer. As I have noted before, AC input makes it easier to generate positive and negative rails for the amplifier so I can see the motivation. Then again, the transformer is inefficient and quite large.

Up on top you see a connector you don't normally see on a pure analog amplifier: the USB-C for firmware upgrades! A supervisory processor handles protection which can be reprogrammed as needed. Indeed, during testing I pushed the unit hard with 12 ohm load well into clipping and it shut down with a sequence of LED lights. Once it cooled a bit, it enabled the device to function again.

The other change which we have seen recently from Topping is use of 1/4 inch input for balanced interconnections. They take up a lot less space than XLR so you can have the same rich set of connectivity including pre-amp in this small enclosure. 1/4 balanced is extremely popular in pro audio so there is plenty of cables and adapters for it if you are not situated currently to use them. And I believe a set of adapters come with the unit.

Topping L50 Measurements
There are many combinations here to test so I limited the input to balanced but measured both balanced and unbalanced headphone output. Let's start with balanced input:

View attachment 150532

And now RCA In:

View attachment 150562

Exceptional performance yet again, almost in the top position of our rankings for SINAD:

View attachment 150563

Here are our noise specs which are stellar:

View attachment 150535

This is what great SINAD does for you at the top of the class: incredibly low noise where you need it with sensitive IEMs:

View attachment 150536

Anyone who says SINAD is not important doesn't understand this dynamic, pun intended.

Frequency response is flat of course to beyond what we need:

View attachment 150537

The main business of a headphone amp is producing power though to drive more difficult headphones. So let's test that with 300 ohm load:
View attachment 150580

My standard for power output is 100 milliwatts and the L50 sails way past that which is great.

Let's switch to other extreme with 32 ohm load, emphasizing current delivery as opposed to voltage:

View attachment 150581

This is a ton of power coming out of this little box.

Sweeping the load and measuring power we get:
View attachment 150542

The main difference here compared to bigger brothers is that it clips with higher impedances whereas they don't. Up to nearly 7 volts there is no load dependency.

Finally here is our channel matching which is excellent for an analog control:
View attachment 150543

As usual your mileage may vary.

Listening Tests
Surprise, surprise, the L50 aces my subjective tests. What can I say. Whether I used the Sennheiser HD650 or Drop Ether CX, there was incredibly clarity, detail, authoritative bass, etc. My ears would scream before the amplifier even got barely unhappy as far as volume.

Conclusions
Hit after hit is the expression that always comes to mind when testing Topping products. Engineering done properly would be another saying. Compare this to many high-end products which barely get verified at all to see if they are what they think they are (transparent and well engineered). We do have some departure in form factor and functionality most of which are positive in my view. You get more choices and more to decide.

It is my pleasure to recommend the Topping L50.

Note: I have no commercial connection of any sort of shape with Topping or any other company for that matter. Don't spread rumors otherwise or I will personally show up and whack you in the back of the head! Many companies send me products and when they perform this well, they get my accolades.

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Hi. Does the L50 have identical power output if it is used in pure single ended configuration (rca input + single ended output) compared to its (XLR input) setting. I have a Topping E30 and a Magni 3 and I am looking for an amp for more power via (single ended input + single ended output) for my Sennheiser hd 650. I am planning to buy L50 but I am concerned regrading any decrease in power output if it is used in (single ended input + single ended output) with a dac like E30. I don't really want to buy L30 as L50 has more power. So I would like to know what is real power output of L50 in (single ended input + single ended output) at 300 ohm load.