Review and Measurements of Topping DX3Pro DAC and Headphone Amp

[azxswq]

I bought this via Massdrop.
Wish me luck!

 

[Wolven]

Mine has an intermittent noise in the right earpiece as well on high gain only. Seems to go away if I unplug the RCAs. I discovered today that I can have the RCA cables not plugged into anything but the DX3 (just hanging loose from the back not connected to any speakers, ect.) and I'll get the same intermittent noise on high gain.

I have experienced noise from the right speaker and was surprised as this has never happened before.
The noise would come and go, while playing in exclusive WASAPI mode, we are talking pure DAC usage.

I was able to pinpoint the problem.
My Volume mixer is always muted for the system sounds and under sound I have selected 'No Sounds'.
When I changed, personalization settings, background etc. I didn't notice that this change activated a sound scheme for windows sounds.
Of course window sounds didn't play as I have those muted under volume mixer.
However, the interference was created, probably crappy drivers.
The moment I changed the sound theme to 'No Sound' the interference stopped.

 

[finneybear]

I had the same thing. After several plugging of the power adapter and resetting it to the factory settings, the processor started working normally. But after that, it turned out that the right headphone output channel is not working well. There was a strong hiss in the right earpiece. When the +9 db mode was turned on, a constant voltage was generally output to the right earpiece. Left earphone and line-out worked fine.

Probably a bad cap. Are the RCA outputs OK?

 

[finneybear]

The basic mod is almost done. Still waiting for a few parts for the LPF hence no sound otherwise the unit is functional 100% with stock power supply.

Will leave the unit run over night to see whether there's any stability problem.

 

[gypsygib]

I have experienced noise from the right speaker and was surprised as this has never happened before.
The noise would come and go, while playing in exclusive WASAPI mode, we are talking pure DAC usage.

I was able to pinpoint the problem.
My Volume mixer is always muted for the system sounds and under sound I have selected 'No Sounds'.
When I changed, personalization settings, background etc. I didn't notice that this change activated a sound scheme for windows sounds.
Of course window sounds didn't play as I have those muted under volume mixer.
However, the interference was created, probably crappy drivers.
The moment I changed the sound theme to 'No Sound' the interference stopped.

Just tried that, no luck unfortunately. I get the sound even if I unplug the usb cord. It sounds like a radio interference (I think) but I've never heard it on my other dac/amps and it only comes on with the RCA cables connected and the DX3 set to output through headphones. Maybe my RCA port wasn't soldered right? Or perhaps the headphone port? Don't really know much about these things.

 

[splkn]

The basic mod is almost done. Still waiting for a few parts for the LPF hence no sound otherwise the unit is functional 100% with stock power supply.

Tell me please where did you buy Elna Silmic II?

 

[freaksamael]

Tell me please where did you buy Elna Silmic II?

audiophonics.fr ; search for ELNA SILMIC II.

 

[Newbie]

Hi i have the dx3 pro and hd650.
Will high gain mode drive these better? I see it gives 123 mw while low gain mode gives 14 mw. Should it affect the audio quality of the HD650?

 

[Veri]

Hi i have the dx3 pro and hd650.
Will high gain mode drive these better? I see it gives 123 mw while low gain mode gives 14 mw. Should it affect the audio quality of the HD650?

It's really quite easy. Use low gain until you max it out, and then go high gain. You should not need high gain at all times if you listen at "normal" listening levels I hardly ever had to switch gain mode.

It should sound the same but low gain has the benefit of lower overall noise floor.

 

[simonchretien]

Hi i have the dx3 pro and hd650.
Will high gain mode drive these better? I see it gives 123 mw while low gain mode gives 14 mw. Should it affect the audio quality of the HD650?

I'd only switch to high gain if I wanted to get deaf.

 

[Newbie]

Thanks guys. i'll keep using low gain.

 

[la2ygoo]

Hi i have the dx3 pro and hd650.
Will high gain mode drive these better? I see it gives 123 mw while low gain mode gives 14 mw. Should it affect the audio quality of the HD650?

use low gain unless is not loud enough to you

 

[aka_Z]

I bought this via Massdrop.
Wish me luck!

Me too

Then I checked this topic again and saw so many problems... Well, we gonna need luck

 

[vicksaint]

Hello everyone.
I received my DX3 Pro last February 19th.
Serial number: 1901594466

Unfortunately I'm not a lucky person.
In just one week of using the DX3 Pro has already gone into Stand By 2 times, yes twice!!!
I was listening to music and without anything else that could cause something the DX3 Pro went into stand by mode, foobar2000 continued to play the songs (FLAC files) but no sound came out and the TOPPING DX3 Pro remains asleep, I had to disconnect it from the electricity to DX3 Pro wake up again.
I'm using the original TOPPING DX3 Pro power supply (15V 1A).
I think doing this often will cause the equipment to completely break at any moment, turn off and on the power supply repeatedly will end up permanently damaging the DX3 Pro.

This equipment definitely has serious problems, it is not very reliable and it is a matter of luck to have a DX3 Pro that works without problems.
I will try to find out from the seller what I can do with this defective equipment.

Another customer who has problems with a DX3 Pro, and keep counting defective DX3 Pro...

 

[ChuckT]

The basic mod is almost done. Still waiting for a few parts for the LPF hence no sound otherwise the unit is functional 100% with stock power supply.

Will leave the unit run over night to see whether there's any stability problem.

View attachment 22471View attachment 22473

Nice work. I was surprise you did not replace the cap for the power supply of the analog output . The caps next to the 2 opamp and the caps at the output of the 2 switching ic output for the +/- 10V.
I don't really like ceramic smd caps for decoupling the opamps.

 

[salvatorebg]

Can someone explain how to configure DX3 PRO in windows 10?
I can not bypass windows volume control.
And why this dac does not change sample rate on display according to sample rate of the music file (it is always 44.1)?
Thank you

 

[finneybear]

Mine has an intermittent noise in the right earpiece as well on high gain only. Seems to go away if I unplug the RCAs. I discovered today that I can have the RCA cables not plugged into anything but the DX3 (just hanging loose from the back not connected to any speakers, ect.) and I'll get the same intermittent noise on high gain.

In DX3, the RCA outputs will go directly to the headphone amp. No relay in the middle to switch off the RCA outputs. In your case, the long RCA cable will behave like an antenna for the headphone amp hence the noise.

 

[finneybear]

Tell me please where did you buy Elna Silmic II?

I usually go with mouser.com for audio related parts.

The enclosure is small so watch out for the height of those big Silmics. There are +-10V across the headphone amp so to be safe, it will be better to use 16V or 25V parts. You may want to try shorter 47uf instead of 100uf. Dont think you will lose much bass there.

The main power entry cap is critical. I am using a 330uf/25V solid polymer here. It serves as the main power reserve for the whole system so hopefully the auto stand-by problem will mostly go away. You can make it as big as 470uf. Regular low ESR cap will not cut it as you need a cap with very good HF performance, solid polymer that is.

Those 100uf/25V SMD caps are a new genre hybrid cap. They have the HF performance/large current of solid polymer caps and the low leakage of low-ESR caps. It has the best of both worlds. Again, only mouser.com carries them.

 

[finneybear]

Nice work. I was surprise you did not replace the cap for the power supply of the analog output . The caps next to the 2 opamp and the caps at the output of the 2 switching ic output for the +/- 10V.
I don't really like ceramic smd caps for decoupling the opamps.

Mmmm... you meant the yellow caps around OPs? They are solid polymers from AVX. Both OPs have +-10 power supply. Cant find the Kemet KOCAP with 25V rating at the right size hence use the polymer from AVX. The LFP caps are film SMD parts.

The 100uf/25V SMD caps are CDE HZA type, it's a new generation hybrid cap.

 

[Toku]

Can someone explain how to configure DX3 PRO in windows 10?
I can not bypass windows volume control.
And why this dac does not change sample rate on display according to sample rate of the music file (it is always 44.1)?
Thank you

It all depends on Windows setting.
Many methods of setting are explained on the Web. If you use an audio player such as Foober 2k, you can play it more easily. You do not have to worry.