Topping L30 II Review (Headphone Amp)

[half_dog]

What will the HS01 provide compared to the galvanic isolation in the SDA-6?

Oh sorry. I didn't know about it. In this case, there's no benefits... Maybe you got a defective unit :/
I'm a little surprised with this interference complain, you are not the first person. I've had a few L30s with me and none of them shown this kind of problem.
I hope you can solve it.

 

[Killerind]

I had been eyeing the Topping L30ii&E30ii after reading your reviews and finally pulled the trigger and bought directly from Topping when I travelled to China a few months later.
I paired them with the HiFiMan Edition XS.
I'm new to the audiophile world and I'm trying to figure out is what gain setting to use.
Low gain at 50% or Medium gain at 20%? I'm not sure if I understand the science correctly as yet. They are sufficiently loud enough on low gain but would I be getting more benefits on medium gain?

 

[staticV3]

@Killerind use the lowest gain you can get away with. Set it to medium only if 100% volume on low isn't loud enough.

 

[Ahmonge]

They are sufficiently loud enough on low gain but would I be getting more benefits on medium gain?

Try both ways and use the one that sounds better to you.

 

[wanghao]

The volume imbalance in L30II is intolerable.
Why has it deteriorated from L30?

https://www.audiosciencereview.com/forum/index.php?attachments/topping-l30-headphone-amplifier-channel-balance-audio-measurements-png.77401/

 

[Roland68]

The volume imbalance in L30II is intolerable.
Why has it deteriorated from L30?

https://www.audiosciencereview.com/forum/index.php?attachments/topping-l30-headphone-amplifier-channel-balance-audio-measurements-png.77401/

Who says it got worse?
What you are seeing is the right/left imbalance of this measured device. Since every potentiometer is slightly different, the next device can be much better or worse at this point.
And this applies not only to the L30 and L30 II, but also to all other devices that use a normal potentiometer, no matter how good or bad the right/left imbalance of the measured device is.

 

[Taschenrechner]

I had to put a thick steel plate on top of my desk to stop the unit from picking up my phone signals.

 

[Roland68]

I had to put a thick steel plate on top of my desk to stop the unit from picking up my phone signals.

The question would be whether the irradiation occurs directly into the device or via the connected cables...

 

[Sokel]

The question would be whether the irradiation occurs directly into the device or via the connected cables...

How thick aluminum should be to avoid such?Or it doesn't matter?
I rule out the cables since we have seen this with all kinds of balanced and unbalanced (including coaxial).

 

[Roland68]

How thick aluminum should be to avoid such?Or it doesn't matter?
I rule out the cables since we have seen this with all kinds of balanced and unbalanced (including coaxial).

It's not that easy with EMC.
But of course, if cables stopped acting as antennas, that would be easier.
With the L30 housings, you first have to check whether all 3 housing parts have a clean electrical connection, otherwise the shielding will not work well.

- Does the noise get louder and quieter as you turn the volume control?
- Is the noise still there or is it less if you unplug the RCA cables?

 

[Taschenrechner]

The question would be whether the irradiation occurs directly into the device or via the connected cables...

I tested it without any cables connected but different headphones. (no dac connected) and the problem presisted even after replacing with another unit.

I think this device is completely unshielded when it comes to certain RF. You can test it by calling a disconected number and putting it near the unit. you should be able to hear loud noise coming from the L30 ii.

 

[Taschenrechner]

It's not that easy with EMC.
But of course, if cables stopped acting as antennas, that would be easier.
With the L30 housings, you first have to check whether all 3 housing parts have a clean electrical connection, otherwise the shielding will not work well.

- Does the noise get louder and quieter as you turn the volume control?
- Is the noise still there or is it less if you unplug the RCA cables?

noise gets louder the higher the volume / gain. But not by much it is already pretty loud even at moderate volume level.

RCA cables on or off made no diffrence with my units.

How thick aluminum should be to avoid such?Or it doesn't matter?
I rule out the cables since we have seen this with all kinds of balanced and unbalanced (including coaxial).

the plate is 2mm thick. I would think 1mm might also be enough. I only had this plate randomly laying arround so I tryed this "solution" and it worked. Think of hi-fi products trying to "improve" the sound of gear. This could be a legit one lol. I ordered this plate from amazon for a project once. they're not super expensive.

I can now lay my phone near my amp (on my desk) and I never hear any random crackle or noises.

 

[half_dog]

That sounds so weird for me... As I told before, I had the opportunity to test some L30 (even those before the upgrade) units and none of them had this problem. Some of them came with some imbalance in low volume, but no interference when connected to a grounded source. Do you a multimeter around to test if the case is connected to ground? And may I ask if yours RCA cables are unidirectional?

 

[Taschenrechner]

That sounds so weird for me... As I told before, I had the opportunity to test some L30 (even those before the upgrade) units and none of them had this problem. Some of them came with some imbalance in low volume, but no interference when connected to a grounded source. Do you a multimeter around to test if the case is connected to ground? And may I ask if yours RCA cables are unidirectional?

I am talking solely about the L30 ii not L30.

I do not have a multimeter.

RCA cables are the ones shenzhenaudio delivers for free with the DAC/AMP combo. https://shenzhenaudio.com/products/topping-e30-ii-l30-ii-rca-cable-combo


but testing it with all sorts of different RCA cables makes no difference. Still waiting for someone to do the simple calling phone to the unit test. I wonder if this is an issues with all units sold.

 

[half_dog]

I am talking solely about the L30 ii not L30.

I know it, but they share some similarities... I'm wondering if the new circuit is so susceptible to EMI. There is a L30II coming for me but probably it will only in a month. Soon as I get it I will try to do some tests.

 

[Taschenrechner]

I know it, but they share some similarities... I'm wondering if the new circuit is so susceptible to EMI. There is a L30II coming for me but probably it will only in a month. Soon as I get it I will try to do some tests.

nice mate. looking forward for those tests. if you might find a simple solution to somehow improve the L30IIs isolation from EMI that be ace. thank you.

 

[Roland68]

I tested it without any cables connected but different headphones. (no dac connected) and the problem presisted even after replacing with another unit.

I think this device is completely unshielded when it comes to certain RF. You can test it by calling a disconected number and putting it near the unit. you should be able to hear loud noise coming from the L30 ii.

I've also had the L30 II here and my iPhone next to it and on top of it too, but had no problems.
That's why I'm a bit surprised...

 

[Taschenrechner]

I've also had the L30 II here and my iPhone next to it and on top of it too, but had no problems.
That's why I'm a bit surprised...

did you try calling the number 5595559599555555599 and setting it on top of it?

 

[Roland68]

did you try calling the number 5595559599555555599 and setting it on top of it?

???

 

[Taschenrechner]

???

try calling a random number that will lead to an unavailable connection (no connection under this number) just so your phone starts sending out the heavy radiation and see if your unit blocks those signals as well.