Loxjie A30 Amplifier Review

[tsoltan]

Hi, I'm new to the forum. Got here looking for a small amp/DAC for my desk speaker as the old amp was breaking down. With some googling I landed here and found this nice loxjie A30. Got mine a month ago and really like it so far. Though I don't consider my self a audiophile nor am I actually listening to that much music. But I built my own speakers and I'm quiet interested in the technical aspects of audio.
So I had the itch to know what the A30 looks like on the inside.

Though some of you might also curious so here are some pictures.

View attachment 115080View attachment 115081View attachment 115082View attachment 115083View attachment 115084View attachment 115085View attachment 115090View attachment 115091View attachment 115092View attachment 115093View attachment 115094View attachment 115095View attachment 115096View attachment 115098View attachment 115099View attachment 115100

Do you think would it be possible to replace qcc3008 with a newer chip to support ldac for ex btm875(csr 8675) ?
https://a.aliexpress.com/_9fQsOu

 

[stefan0n]

Hi All
I'm new here, also if I was reading from some time with big interest the great reviews and discussions.
I bought this little thing some months ago and wish to ask about the headphone output. From the review I know that it's not so good, but what about the noise level you're experiencing when not playing music? Sometimes I can't use the speakers so I connect a pair of 16ohm IEM, and then I ear a clear hiss noise when nothing is playing, with any input. I'm using an adapter for connecting the headphone but I don't think this is the problem. What bothers me too is the fact that connecting the same headphone to a cheap USB audio adapter output, connected to my pc, this is so much quieter... any experiences about this?

 

[enno]

Do you think would it be possible to replace qcc3008 with a newer chip to support ldac for ex btm875(csr 8675) ?
https://a.aliexpress.com/_9fQsOu

I assume you think of a "simple" swap. That I think is unlikely. From my googling these modules seam to differ alot and I couldn't see any standard for the pinouts and footprint.
It probably is possible but i don't think the time needed to reverse engineer every thing is feasible. I tried to find the specs for the qcc3008 module and think i found it only on a chines site. So there starts the trouble.

 

[enno]

I would imagine the USB is used both as an input and as the connection for your PC to adjust the DSP

Man I wish I had found this before. I have bought about $500 in components recently and this would replace all of them.

Has anyone played with the DSP? Would it allow me to highpass speakers and lowpass the SW out? What are the adjustments like?

What DSP are you speaking of? I had the impression that there is only a really simply EQ with like 5 predefined settings, which only effect the highs and lows and nothing in the mids.

 

[Djörk]

Hi All
I'm new here, also if I was reading from some time with big interest the great reviews and discussions.
I bought this little thing some months ago and wish to ask about the headphone output. From the review I know that it's not so good, but what about the noise level you're experiencing when not playing music? Sometimes I can't use the speakers so I connect a pair of 16ohm IEM, and then I ear a clear hiss noise when nothing is playing, with any input. I'm using an adapter for connecting the headphone but I don't think this is the problem. What bothers me too is the fact that connecting the same headphone to a cheap USB audio adapter output, connected to my pc, this is so much quieter... any experiences about this?

I'm also experiencing this issue. When the source volume is low (e.g. Windows at 50%) there is a noticeable hiss on the right channel, through speakers and headphones on optical and aux inputs. Lowering the source volume further makes it much worse. It doesn't seem to be present on the USB input or when the source volume is 100%.

I've emailed hifi-express.com but haven't received a reply as of yet.

 

[Toku]

Hi All
I'm new here, also if I was reading from some time with big interest the great reviews and discussions.
I bought this little thing some months ago and wish to ask about the headphone output. From the review I know that it's not so good, but what about the noise level you're experiencing when not playing music? Sometimes I can't use the speakers so I connect a pair of 16ohm IEM, and then I ear a clear hiss noise when nothing is playing, with any input. I'm using an adapter for connecting the headphone but I don't think this is the problem. What bothers me too is the fact that connecting the same headphone to a cheap USB audio adapter output, connected to my pc, this is so much quieter... any experiences about this?

Does the noise disappear at the minimum and maximum volume positions and become loudest at around 12 o'clock?

 

[Toku]

I would imagine the USB is used both as an input and as the connection for your PC to adjust the DSP

Man I wish I had found this before. I have bought about $500 in components recently and this would replace all of them.

Has anyone played with the DSP? Would it allow me to highpass speakers and lowpass the SW out? What are the adjustments like?

LOXJIE A30 does not have a DSP.

The A30 is equipped with the NJW1194 digitally controlled analog electronic volume. In addition to the electronic volume function, the NJW1194 has an analog EQ function and an analog input selector.
This makes preset EQ, tone control, and input signal switching.
There is no detailed data inside the LOXJIE A30, but I imagine that the signals are connected as shown below.

[BT] >> QCC3008 >> (I2S) >> ES9023 DAC >> NJW1194 Elctronic Vlume >> MA12070 >> SP output

[OPT, Coax] >> LC89091JA >> (I2S) >> ES9023 DAC >> NJW1194 Elctronic Vlume >> MA12070 >> SP output

[USB input] >> ALC4050 >> NJW1194 Elctronic Vlume >> MA12070> SP output

[RCA input] >> NJW1194 Elctronic Vlume >> MA12070> SP output

[SW output] >> NJW1194 Elctronic Vlume >> TL072 >> SW output

 

[shilent]

[USB input] >> ALC4050 >> NJM1194 Elctronic Vlume >> MA12070> SP output

It's using a Realtek DAC via USB?

Does this explain the lower volume output when using USB, and does this mean we should use optical for the Sabre DAC?

 

[boselover61]

It's using a Realtek DAC via USB?

Does this explain the lower volume output when using USB, and does this mean we should use optical for the Sabre DAC?

Probably best to just use an external dac alltogethrt

 

[stefan0n]

Does the noise disappear at the minimum and maximum volume positions and become loudest at around 12 o'clock?

No, I'm not experiencing such kind of variations. I get a slow increase in the noise with volume up to about level 40, and more consistent after up to the max level.

 

[stefan0n]

I'm also experiencing this issue. When the source volume is low (e.g. Windows at 50%) there is a noticeable hiss on the right channel, through speakers and headphones on optical and aux inputs. Lowering the source volume further makes it much worse. It doesn't seem to be present on the USB input or when the source volume is 100%.

In my case the hiss I have is the same for each input, be it connected or not, my usually used input source is USB, and it seems proportional to A30 volume level and not to the output of the pc driving the USB. I found also that it changes a little with the A30 display turned off instead of on...

 

[Toku]

It's using a Realtek DAC via USB?

Does this explain the lower volume output when using USB, and does this mean we should use optical for the Sabre DAC?

Detailed information about the internal configuration of LOXJIE A30 has not been released. All are my guesses from the board configuration and the parts used. So it may be wrong.

The signal line from the USB connector is connected to the Realtek ALC4050. Realtek ALC4050 is a commonly used DAC chip for USB Phone Dongle.
Therefore, the digital signal from USB is converted to an analog signal by ALC4050 and connected to the input of NJW1194 of the electronic volume.
From this, I think that the USB connection works the same as the commercially available "USB Phone Dongle DAC".

The USB, OPT, COAX, and BT of this product are all simple connections that prioritize convenience. It is such a configuration from the product price.
The best way to use the A30 in terms of sound quality is when an analog signal from an external DAC is connected to the RCA. The same is true for the SMSL SA300.
Whether you prioritize convenience or sound quality depends on your purpose of use.

I don't know the volume level issue as it involves the connected device as well.

Postscript
The sampling rates that can be played back via USB input are 44.1kHz, 48kHz, 96kHz, 192kHz, and 384kHz. It does not support 88.2kHz, 176.4kHz & 352kHz.

 

[Toku]

It's using a Realtek DAC via USB?

Does this explain the lower volume output when using USB, and does this mean we should use optical for the Sabre DAC?

I thought it was the same problem I had with the LOXJIE amp before and asked.
But it doesn't seem to be the cause I expected.

-------------------------------------------------------
I reported on the Loxjie A30 signal path, but after further verification of BT it was wrong.

[BT] >> QCC3008 >> (I2S) >> ES9023 DAC >> NJM1194 Elctronic Vlume >> MA12070 >> SP output
This description
[BT] >> QCC3008 >> NJM1194 Elctronic Vlume >> MA12070 >> SP output
I will correct it.

Therefore, the ES9023 DAC chip is used only for OPT and COAX S/PDIF signals.
The Loxjie A30 is a model based on the SMSL SA300 with the addition of OPT and COAX S/PDIF inputs using the ES9023 DAC chip. Other parts and circuit configuration are almost the same as SA300. The board pattern around the MA12070 and the circuit design without an output filter are the same.
Originally Loxjie and SMSL are the same company, so the designs will be similar.

 

[boselover61]

I thought it was the same problem I had with the LOXJIE amp before and asked.
But it doesn't seem to be the cause I expected.

-------------------------------------------------------
I reported on the Loxjie A30 signal path, but after further verification of BT it was wrong.

[BT] >> QCC3008 >> (I2S) >> ES9023 DAC >> NJM1194 Elctronic Vlume >> MA12070 >> SP output
This description
[BT] >> QCC3008 >> NJM1194 Elctronic Vlume >> MA12070 >> SP output
I will correct it.

Therefore, the ES9023 DAC chip is used only for OPT and COAX S/PDIF signals.
The Loxjie A30 is a model based on the SMSL SA300 with the addition of OPT and COAX S/PDIF inputs using the ES9023 DAC chip. Other parts and circuit configuration are almost the same as SA300. The board pattern around the MA12070 and the circuit design without an output filter are the same.
Originally Loxjie and SMSL are the same company, so the designs will be similar.

So thats why usb has lower volume than coax and opt. They have lower output

 

[JohnnyN]

So thats why usb has lower volume than coax and opt. They have lower output

Thanks for these explanations—I was experiencing lower volume with USB and thought it was maybe just my unit. Apologies for interrupting with something off-topic, but I’m new here/new to the audio world in general and in need of some advice. I purchased the Loxjie A30 and while I do really like it, it feels like my speakers want more power, even though I don’t listen at crazy loud volumes. My speakers are JBL Studio 530s (86 db), and I am not using them on a desktop/near-field—I’m using them in a living room/kitchen area. Would an ICEPower 125ASX2 amplifier + Topping E30 or D50 DAC provide a noticeable upgrade / be better suited for my use? I stream all music.

 

[boselover61]

Thanks for these explanations—I was experiencing lower volume with USB and thought it was maybe just my unit. Apologies for interrupting with something off-topic, but I’m new here/new to the audio world in general and in need of some advice. I purchased the Loxjie A30 and while I do really like it, it feels like my speakers want more power, even though I don’t listen at crazy loud volumes. My speakers are JBL Studio 530s (86 db), and I am not using them on a desktop/near-field—I’m using them in a living room/kitchen area. Would an ICEPower 125ASX2 amplifier + Topping E30 or D50 DAC provide a noticeable upgrade / be better suited for my use? I stream all music.

What volume level do you have the loxjie on? I usually leave them at 50 max. Over that and speakers distort

 

[shilent]

Probably best to just use an external dac alltogethrt

The best way to use the A30 in terms of sound quality is when an analog signal from an external DAC is connected to the RCA. The same is true for the SMSL SA300.
Whether you prioritize convenience or sound quality depends on your purpose of use.

How about a computer internal sound card like the Sound Blaster X AE-5? Amirm gave it a good review. Should the AE-5 to the Loxjie A30 Aux in provide better sound quality than optical? I have the AE-5, but can't tell a difference between Aux and Optical.

 

[Toku]

How about a computer internal sound card like the Sound Blaster X AE-5? Amirm gave it a good review. Should the AE-5 to the Loxjie A30 Aux in provide better sound quality than optical? I have the AE-5, but can't tell a difference between Aux and Optical.

I don't have a Loxjie A30 or Sound Blaster X AE-5. Instead, I own three SMSL SA300s.
The SA300's USB input has the same circuit configuration as Loxjie, but is clearly inferior to the RCA input.
You can clearly feel the difference in sound when comparing the case where the PC is directly connected to the USB input of the SA300 and the case where the audio output of a good quality USB-DAC is input to the RCA of the SA300. Also, the difference is big.
I encourage you to see the difference in sound for yourself.

 

[boselover61]

I don't have a Loxjie A30 or Sound Blaster X AE-5. Instead, I own three SMSL SA300s.
The SA300's USB input has the same circuit configuration as Loxjie, but is clearly inferior to the RCA input.
You can clearly feel the difference in sound when comparing the case where the PC is directly connected to the USB input of the SA300 and the case where the audio output of a good quality USB-DAC is input to the RCA of the SA300. Also, the difference is big.
I encourage you to see the difference in sound for yourself.

All I notice is potentially louder volume due to higher output voltage. Also the external dac might be less noisy than the built in realtek dac? I don't notice a huge difference really.

 

[enno]

@Toku Thanks for the details. I had no time to trace the componets on the picture in detail but on first glance i feared that this is whats going on, because there weren't many lines going to the ES9023 and no muxing which could feed all the different srouces through the ES9023.

I think this largely reduces the usability off this product, as I think it's quit fitting for a clean desk setup with a laptop, where few components are desirable. But as not that many devices have toslink, SPDIF or a good DAC there is at least for me a lot of the good gone.
My setup is USB for latop/desktop and TOSLINK for airplay via appleTV/airport.

@amirm Do you still have the A30 and could you measure the USB an BT Inputs again?