Topping L30 II Review (Headphone Amp)

[raif71]

Does anyone know if this headphone amp is fine for the Audio Technica ATH R70x. I messaged them and they claimed they would not recommend I use this amp with their headphones and that the input impedance was very low. Not sure why exactly that matters. They recommend I use a Bellari HA543 instead which seems worse? I currently use this topping along with their DAC. I started messaging Audio Technica about this cause I noticed some distortion on some of my tracks I listen to.

I googled this Bellari...quite interesting (able to color sound) and almost or the same price as Topping L30II

 

[Trickle2x2]

I googled this Bellari...quite interesting (able to color sound) and almost or the same price as Topping L30II

Curious though if there is any reason to go with that one over the Topping for my Audio Technica ATH R70x. Seems like the company thinks the output impedance is an issue for compatibility with the Topping and headset.

 

[raif71]

Curious though if there is any reason to go with that one over the Topping for my Audio Technica ATH R70x. Seems like the company thinks the output impedance is an issue for compatibility with the Topping and headset.

could be...at 470ohms, it is quite high for an entry level amp like the L30II

 

[half_dog]

could be...at 470ohms, it is quite high for an entry level amp like the L30II

That's not a "problem" for L30 II. High impedance requests high voltage swing which L30 II has enough for safety listening levels. It might be able to output around 240mW over 470 ohm. And with a sensitivity closer to a HD600, 240mW is sufficient to reach 115dB.

 

[Trickle2x2]

That's not a "problem" for L30 II. High impedance requests high voltage swing which L30 II has enough for safety listening levels. It might be able to output around 240mW over 470 ohm. And with a sensitivity closer to a HD600, 240mW is sufficient to reach 115dB.

So I should be fine with the L30 II for my ATH R70x? And possibly the distortion I heard is probably just a bad mix in a few tracks?

 

[Rja4000]

could be...at 470ohms, it is quite high for an entry level amp like the L30II

So I should be fine with the L30 II for my ATH R70x? And possibly the distortion I heard is probably just a bad mix in a few tracks?

Yes.
Amir measured it at 300 and 600 Ohm.
No saturation and more than 10V.

That's enough to drive the 99dB/mW AT at (literally) deafing level.


Its max output power at such impedance would be around 300mW. Still far from the max 1000mW the AT is advertised for. But nobody really needs or wants 129dB SPL.

That doesn't mean the AT doesn't show an audible level of distortion if you push it hard enough. But that would be the same with any other similarly powerful amp then.

 

[Trickle2x2]

Yes.
Amir measured it at 300 and 600 Ohm.
No saturation and more than 10V.

That's enough to drive the 99dB/mW AT at (literally) deafing level.


Its max output power at such impedance would be around 300mW. Still far from the max 1000mW the AT is advertised for. But nobody really needs or wants 129dB SPL.

That doesn't mean the AT doesn't show an audible level of distortion if you push it hard enough. But that would be the same with any other similarly powerful amp then.

So if I have the volume nob at about ~60% on high gain I shouldn’t hear any distortion then? Also still not sure why they mentioned the output impedance being low as a bad thing for these headphones.

 

[Rja4000]

So if I have the volume nob at about ~60% on high gain I shouldn’t hear any distortion then?

At approx. 60% level setting, High gain, feeding it with 2V, I get around 4.6V output at 300 Ohm
If we get the same on 470 Ohm, that's 45 mW
Or 115dB SPL if we trust AT specs.

It's pretty possible the AT starts to distort badly at such level.
Same for your ears.
But the L30 II, as per Amir's measurements, would have distortion at or below -115dB at that level.

Also still not sure why they mentioned the output impedance being low as a bad thing for these headphones.

I'm afraid I have no clue.

 

[Trickle2x2]

At approx. 60% level setting, High gain, feeding it with 2V, I get around 4.6V output at 300 Ohm
If we get the same on 470 Ohm, that's 45 mW
Or 115dB SPL if we trust AT specs.

It's pretty possible the AT starts to distort badly at such level.
Same for your ears.
But the L30 II, as per Amir's measurements, would have distortion at or below -115dB at that level.

I'm afraid I have no clue.

So I’m probably turning the volume up to high on this amp then for those headphones? Any idea on if that Bellari HA543 I mentioned early that AT recommended would work any better for my situation?

 

[Rja4000]

So I’m probably turning the volume up to high on this amp then for those headphones? Any idea on if that Bellari HA543 I mentioned early that AT recommended would work any better for my situation?

How could that work better ?
If you want that level of loudness and if you hear distortion coming from the headphones at that level, since that's not coming from the amp, your only option is to change the headphones.

EDIT:
I didn't remember, but Amir measured the AT.
Distortion is VERY HIGH at low frequencies (harmonics will be audible at multiple frequencies)

His conclusion:

Normal listening is fine but just know that you don't have much headroom here.

(From his measurements, at 4.6V, you should get around 117dB SPL. That's quite loud.)

 

[Trickle2x2]

How could that work better ?
If you want that level of loudness and if you hear distortion coming from the headphones at that level, since that's not coming from the amp, your only option is to change the headphones.

EDIT:
I didn't remember, but Amir measured the AT.
Distortion is VERY HIGH at low frequencies (harmonics will be audible at multiple frequencies)

His conclusion:

View attachment 292965

(From his measurements, at 4.6V, you should get around 117dB SPL. That's quite loud.)

I believe I misread your explanation and thought you were saying the amp could be causing distortion. Thanks for the info and detailed responses, I’m new to nice headphones.

 

[jmillar]

Channel and balance is just a thing with cheaper pots.
Something has to give at these lower prices.

In the old days this was corrected by the balance knob that we more or less took for granted.

 

[jmillar]

Last time I was watching other reviewers than Amir I heard Joshua Valour complaining that all these topping and smsl devices sound the same, so he will not review them

Josh has just published his amp tier list...
And in the "S" category (superb, supreme, whatever) we can find... the A90 and the A90d.

 

[Trickle2x2]

If anyone uses this amp with the ATH R70x I’d like to hear your opinion on it and where you set your volume nob at and what gain. I found I pretty much have to use high gain to get a decent levels without maxing the volume nob. Typically I’m around the noon posistion.

 

[staticV3]

@Trickle2x2 have you tried measuring your DAC output? If for whatever reason your DAC is outputting a low signal (<2V), then you'd have to turn up the Amp a bunch to compensate.
You can measure the DACs output voltage with a simple multimeter.

 

[Trickle2x2]

@Trickle2x2 have you tried measuring your DAC output? If for whatever reason your DAC is outputting a low signal (<2V), then you'd have to turn up the Amp a bunch to compensate.
You can measure the DACs output voltage with a simple multimeter.

I have a nice Fluke I can use, where do you grab your ground? I’m using the Topping E30 II. Tbh I think it’s probably fine these headphones are pretty high Ohms.

 

[Jimster480]

In the old days this was corrected by the balance knob that we more or less took for granted.

True but that would add additional cost, which would probably be similar to the cost associated with just doing a ladder based volume control with perfect matching.

 

[staticV3]

I have a nice Fluke I can use, where do you grab your ground?

First, download the 60Hz, 0dBFS test tone here.
Make sure there's nothing plugged into the DAC's output.
Import the tone into your player, set playback to loop, and press play.
Then plug an RCA cable into the E30 II (L or R doesn't matter), and probe the other end of the cable like so (multimeter set to V AC):

 

[Trickle2x2]

First, download the 60Hz, 0dBFS test tone here.
Make sure there's nothing plugged into the DAC's output.
Import the tone into your player, set playback to loop, and press play.
Then plug an RCA cable into the E30 II (L or R doesn't matter), and probe the other end of the cable like so (multimeter set to V AC):
View attachment 293407

Okay I’ll test it out. Should I also check the output on my headphone amp also? Tbh both devices are probably working fine and was just curious as to what gain and volume setting most people use on this amp with harder to drives headsets like the Audio Technica ATH R70x.

 

[solderdude]

The ATH R70X is actually really easy to drive. It is a very efficient headphone. It just requires a bit higher voltage than a phone can deliver.
With 104dB/V (100dB/mW) you will not need more than 6V (or 12V when you want Harman bass) =less than 0.1W.
For Harman type bass at impressive levels and using a 2V out DAC you will need 6x gain = 16dB gain.
Most likely you will not be going past 4V or so (30mW) and 2x gain would suffice (+6dB)