Topping A30Pro Review (Balanced Headphone Amp)

[VariousArtists]

Hey guys, is it crazy that the 6.35 output sounds "better" than the 4.4? I have tested the following:

2.5mm (1 cable) to 4.4 and 6.35 adapters, and the latter sounds a bit more "dynamic" / lively.

Does anyone know whether there are any differences in measurement between these 2 outputs?

All the 3 headphone outputs are wired to the same 3 pins on the circuit board (and in parallel). The 4-pin 4.4mm is not truely balanced, it's just for convinence- effectively a built-in 4.4mm balanced to unbalanced adapter.

So the most likely explanation is that there is something wrong with the physical connection for the 4.4mm, somewhere along the signal chain.

 

[staticV3]

So the most likely explanation is that there is something wrong with the physical connection for the 4.4mm, somewhere along the signal chain.

An even more likely explanation is that the difference in sound quality is just placebo, caused by a sighted comparison with considerable dead time when changing outputs.

Fix both of these with a switch box and the perceived difference would most likely disappear.

 

[cenix]

All the 3 headphone outputs are wired to the same 3 pins on the circuit board (and in parallel). The 4-pin 4.4mm is not truely balanced, it's just for convinence- effectively a built-in 4.4mm balanced to unbalanced adapter.

So the most likely explanation is that there is something wrong with the physical connection for the 4.4mm, somewhere along the signal chain.

I don't think something is wrong with the physical connection (I'd have no idea anyway). The 6.35mm also sounds a bit fuller, and this part is really apparent. There is no way that they have volume differential between the both right?

An even more likely explanation is that the difference in sound quality is just placebo, caused by a sighted comparison with considerable dead time when changing outputs.

Fix both of these with a switch box and the perceived difference would most likely disappear.

That is for sure one of the possibilities. But, I've been using this IEM (Chopin) with the 4.4 since first listening session. And the sound was noticeably different when swapping over to the 6.35. I find it more energetic on the latter output every time. If it's just placebo, wouldn't it be more evenly divided? In fact, the bass volume seems to be less on the 4.4 (this could still be placebo, but unlikely to me). I'll try doing a blind test next time.

 

[David_M]

Interesting idea. At some point, did you use an adapter to convert between the two outputs? Maybe that's the cause for the difference you hear.

 

[cenix]

Interesting idea. At some point, did you use an adapter to convert between the two outputs? Maybe that's the cause for the difference you hear.

This is my current setup:

 

[David_M]

This is my current setup:

What are those adapters?

 

[staticV3]

What are those adapters?

DJ35A/DJ44A 2.5mm Balanced Adapter - ddHiFi

Apply to 2.5mm balance earphones cable Its small. Really small. User-Friendly Gadget Every Detail Counts

ddhifi.com

 

[David_M]

This is my current setup:

Maybe the increase crosstalk between the L/R channels due to their closeness in this adapter has a role to play?

 

[cenix]

Maybe the increase crosstalk between the L/R channels due to their closeness in this adapter has a role to play?

I'm pretty positive those adapters themselves don't alter the sound in any way (anything audible anyway).

 

[Bansaku]

Hey folks, got a question. Has anyone tried to dual output to two radically different headphone types and impedance, such as the HD 600 and the HE 1000? I don't need to have 2 headphones as once, however I want to "trick" the A30 Pro into discrete mode for the latter.

 

[staticV3]

Hey folks, got a question. Has anyone tried to dual output to two radically different headphone types and impedance, such as the HD 600 and the HE 1000? I don't need to have 2 headphones as once, however I want to "trick" the A30 Pro into discrete mode for the latter.

It doesn't work like that unfortunately.
According to Topping, the A30Pro will remain in Class A with >250Ω load impedance.
If you plug the HD600 (307Ω) into one jack and the HE1000 (38Ω) into the other, then the Amp will see a load impedance of roughly 1/(1/38+1/307)=33.8Ω

 

[Ahmonge]

A30 Pro sounds wonderfully with low impedance headphones.

 

[frogmeat69]

Drop just put the A30 Pro on sale for $200, link HERE.
Just a heads up, doesn't ship out until March 22, 2024.

 

[JEntwistle]

Would there be any issues using the A30Pro in pass-through mode, with output going into a separate amplifier that is used to power passive speakers?

e.g.:
DAC (E70 used as pre-amp) --->balanced XLR--->A30Pro (pass-through mode; amp turned off) --->balanced TRS ---> power amp (PA3) ---> passive speakers

And then the A30Pro is used as a headphone amp when powered on.

A lot of cables, but does this work?

 

[Ahmonge]

Would there be any issues using the A30Pro in pass-through mode, with output going into a separate amplifier that is used to power passive speakers?

e.g.:
DAC (E70 used as pre-amp) --->balanced XLR--->A30Pro (pass-through mode; amp turned off) --->balanced TRS ---> power amp (PA3) ---> passive speakers

And then the A30Pro is used as a headphone amp when powered on.

A lot of cables, but does this work?

I don't see why not. This is the kind of sceanrio pass-thru on the A30 Pro is designed for. Only take into account that this only works when the unit is off.

 

[JEntwistle]

I don't see why not. This is the kind of sceanrio pass-thru on the A30 Pro is designed for. Only take into account that this only works when the unit is off.

Great. Thanks - I just wanted to sense check that I understand this properly.

And I just found this on the Topping website, which shows this scenario.

 

[Ahmonge]

Great. Thanks - I just wanted to sense check that I understand this properly.

And I just found this on the Topping website, which shows this scenario.

View attachment 337459

That's right, L50 has the same behaviour than the A30 Pro.

 

[HoJ76]

A30Pro on its way to me, to replace an L30 which I also like very much (have another L30 in the system). Can't wait to test what the A30Pro can deliver to my headphones - AKG K701, Sennheiser HD650 and Hifiman Ananda Stealth Magnet

 

[staticV3]

A30Pro on its way to me, to replace an L30 which I also like very much (have another L30 in the system). Can't wait to test what the A30Pro can deliver to my headphones - AKG K701, Sennheiser HD650 and Hifiman Ananda Stealth Magnet

With neither one of those headphones, you'll be able to make use of even 10% of the A30Pro's output power without blowing your ears off

 

[Dunring]

A30Pro on its way to me, to replace an L30 which I also like very much (have another L30 in the system). Can't wait to test what the A30Pro can deliver to my headphones - AKG K701, Sennheiser HD650 and Hifiman Ananda Stealth Magnet

You'll really like it, I just had that Ananda and the Nano version to try for a week. For my A30 Pro with SMSL DL200 as a DAC it was child's play. You'll be in medium gain if you eq with a healthy pre-amp reduction. The only time I've used high gain was equalizing the Hifiman HE6se which is a bottomless pit of power when it's reduced by -6.9db for a profile. I'd recommend splurging the .86 cents to get some thicker rubber feet to elevate it for more air circulation.

https://www.aliexpress.us/item/3256805594906460.html

I have a set of those in the mailbox now, going to stack a couple to keep things cool. It's 105f at the hot spot in the center, so nothing to worry about really. Just raising it a half inch up makes me feel better.