Topping L30 Headphone Amplifier Review

[solderdude]

This is now fixed with an added resistor so no longer an issue.

 

[liu]

that makes sense. I dont have the updated version so dont have chance to reverse engineering the new version.

 

[half_dog]

The NE5532 is not in the audio path.
It just works as a level detector.
It is completely irrelevant what the used quality is as long as it functions as it should.

I thought it was used to compensate DC offset on signal path. Sorry for the confusion caused.

 

[dgnzcn]

I thought it was used to compensate DC offset on signal path. Sorry for the confusion caused.

Haha you messed up
Of course it can be a joke, these kinds of things are in the forums.

 

[half_dog]

It wasn't a joke - I could say it was to get away haha. But It wasn't... after reading all the explanations above this replacement seems a smart choice

 

[tifune]

It can provide 26.6Vpp = 9.4V which in 300 Ohm =290mW
The 250mW would be calculated from 50 Ohm load = 8.6V at the knee of distortion but without the 50 Ohm will be somewhat higher.

Glad you posted this, I'm trying to find a device that can double as both HPA and input buffer for 1ET400. Based on these numbers + spec sheet, am I correct that the L30 can do it if my DAC can push 3V? I believe 1ET400 without pre-gain needs 9V to reach max power

 

[solderdude]

The 1ET400will reach 425W in 4ohm when it receives 9.4V on its input.
As it is single ended the pre-amp needs to drive 2kohm which is not a problem.
To reach the 1ET400 clipping level the L30 needs to be in +9dB setting and your DAC needs to have at least 3.4V output voltage 0dBFS.

 

[KR500]

Just wondered if anyone had measured/compared the WHAMMY headphone amp against the Topping L30 HPA ?

 

[Veri]

Just wondered if anyone had measured/compared the WHAMMY headphone amp against the Topping L30 HPA ?

Former is a pretty old design that might play well with high impedance headphones like HD6xx etc. L30 is lower output impedance lower distortion and much lower noise, plays well with a lot more earphones/headphones and IEMs. Buying a WHAMMY is buying old-generation amplification basically, might not be bad depending on your needs. But hard to compete with current stuff like L30 or something like Drop 789, etc...

 

[KR500]

Former is a pretty old design that might play well with high impedance headphones like HD6xx etc.

Thanks Veri, actually I do have higher impedance headphones , or medium high ( 250 ohms ) so your observation was of interest to me. I do have a couple of low impedance headphones also but don't use them much, or for for serious listening.
I wasn't aware the WHAMMY was considered very old since it debuted in 2017, is it considered old technology in 2021 when compared to the JDS labs Atom or Topping L30 ?

 

[Veri]

Thanks Very, actually I do have higher impedance headphones , or medium high ( 250 ohms ) so your observation was of interest to me. I do have a couple of low impedance headphones also but don't use them much, or for for serious listening.
I wasn't the WHAMMY was considered very old since it debuted back in 2017, is it considered old technology in 2021 when compared to the JDS labs Atom or Topping L30 ?

Hmm I thought it was a fair bit older but okay, 5 years ago, sounds about right

 

[3125b]

It was measured here: https://guides.diyaudio.com/Guide/WHAMMY+headphone+amplifier/3
About 96dB SINAD best case, -0.6dB down @20Hz (at least in that configuration with those specific parts used, it may vary a bit).
I don't know, seems like a lot of work to make something that ends up being mediocre (maybe look for an output impedance spec and note that it doesn't have pre-outs or a gain switch!), plus I bet it will be more expensive than just buying an L30.
But if you are in it for the DIY fun, why not try it.

 

[KR500]

Thanks for the link on the WHAMMY measurements, I had searched but didn't find it.
I built the WHAMMY when it came out and have used it regularly with my first outboard DAC, the Musical Fidelity V-DAC 1 and coaxial input.
Sounds very good with my Beyer 880 250 ohm cans.
Just wondering if the L30 and E30 stack would be worth upgrading to ?

 

[NgtFlyer]

Even if it was replaced, new revision still sounds the same...

I had the very thought to post my experience as I had extensively listened to music through my original 2005 serial unit and now have had plenty of time with my replacement 2012 serial L30.

In short, I have noticed no difference in the sound quality. Same dynamics, same ultra satisfying clear presentation of my music.

The only differences I have noticed:
The new unit's volume control isn't *quite* as linear as the old one, the right channel drops off before the left at the *very* bottom of the volume travel. I consider this a non issue as I don't listen at barely audible levels.
The new unit seems to run a bit cooler than the original.

In the end, I am happy with my replacement L30 and thank Topping for handling the replacement program so efficiently.

 

[tifune]

The 1ET400will reach 425W in 4ohm when it receives 9.4V on its input.
As it is single ended the pre-amp needs to drive 2kohm which is not a problem.
To reach the 1ET400 clipping level the L30 needs to be in +9dB setting and your DAC needs to have at least 3.4V output voltage 0dBFS.

Just curious, were you able to determine that from L30 spec sheet? The sheet lists H gain is 9.5dB with input sensitivity of 3.0V - won't the L30 itself clip at 3.4V ? It's pretty unlikely I'll desire that much volume just trying to understand how it all fits and if there's any discernable benefit to an A50s or A90 for this specific use case. Topping often uses Vpp on their spec sheets and it's throwing me off because I can't figure out the conversion method for plain old V

 

[solderdude]

Specs say +9.5dB, I went with what's on the front panel... +9dB
+9.5dB = 2.98x gain
+9 dB = 2.8x gain

Max U uit is 9.2V acc. to spec sheet (26Vpp) but it does not say at which distortion level.

So to get the L30, in high gain mode, to output 9.2V (is just below the input level of the 1ET400 in SE input mode) you will need 3.08V with volpot in max. position.
So the L30 will not clip when on high gain when you feed it 3.08V.
It also won't clip in M mode when you feed the L30 9.2V
It also won't clip when in L mode you feed the L30 with 28.7V input voltage.

 

[tifune]

Max U uit is 9.2V acc. to spec sheet (26Vpp) but it does not say at which distortion level.

This is what I was missing; ty!

 

[raistlin65]

@amirm, can you update this message on the main page? It doesn't say anything about how the new production models have been fixed to correct this issue.

"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."

 

[Krio]

Sorry for returning on the topic of 2012xxxxx. After I've read a lot of thread pages on this subject, I think that I understand the 90%-10% situation of 2012 version. I just bought mine from a Romanian retailer (avmall.ro). In order to check if I am one of the lucky 90%, I've removed the side screws and loosen the screws above RCA plugs. I attach the pictures. I kindly ask somebody who knows (since I am a noob) that my unit has that ESD protection (I think is the one I circled in the picture).

 

[Vini darko]

Sorry for returning on the topic of 2012xxxxx. After I've read a lot of thread pages on this subject, I think that I understand the 90%-10% situation of 2012 version. I just bought mine from a Romanian retailer (avmall.ro). In order to check if I am one of the lucky 90%, I've removed the side screws and loosen the screws above RCA plugs. I attach the pictures. I kindly ask somebody who knows (since I am a noob) that my unit has that ESD protection (I think is the one I circled in the picture).

Yes you have the ESD fix