Alternative to Loxjie A30 Amplifier

[Hapo]

....I sent the Loxie back and kept SMSL A300....it has one USB input...

 

[Timcognito]

Notice @cyp first post and wanted some advice what amp to get, not anybody's PhD Dissertation on PWM.
I bought the A30 for my son and it sounded great but he uses the coax. Thanks @Hapo for staying on target

 

[Hapo]

...I have not used the USB input...just sayin'...

 

[voodooless]

Notice @cyp first post and wanted some advice what amp to get, not anybody's PhD Dissertation PWM.

Sorry about that

I bought the A30 for my son and it sounded great but he uses the coax. Thanks @Hapo for staying on target

I use they A30 daily with USB, and it’s works absolutely great.

 

[Matias]

Topping MX3s looks like a killer all in one.

 

[Hapo]

Sorry about that

I use they A30 daily with USB, and it’s works absolutely great.

...because China...???...

 

[voodooless]

...because China...???...

Despite China?? I have no idea what you want to say…

 

[Zapper]

Notice @cyp first post and wanted some advice what amp to get, not anybody's PhD Dissertation on PWM.
I bought the A30 for my son and it sounded great but he uses the coax. Thanks @Hapo for staying on target

Personally, I come here for the dissertations!

 

[Hatto]

Notice @cyp first post and wanted some advice what amp to get, not anybody's PhD Dissertation on PWM.
I bought the A30 for my son and it sounded great but he uses the coax. Thanks @Hapo for staying on target

Although lengthy, the discussion was still in context of the question regarding the claim that one product being superior to others based on their topology. As it appears they're doing the exact same thing with single vs multiple electronic components.

 

[Timcognito]

Personally, I come here for the dissertations!

Okay maybe I was a little heavy handed and I am more in need advice than give advice category. No offence to any of you experts. But it was his first post ever and I've been in his spot before wanting some buying help.
Edit: on electronics that is.

 

[Hatto]

Okay maybe I was a little heavy handed and I am more in need advice than give advice category. No offence to any of you experts. But it was his first post ever and I've been in his spot before wanting some buying help.
Edit: on electronics that is.

None taken on my part, hence the explanation.

Being in his/her spot, I also would have appreciated some technical clarity over assumed diffrences based on incomplete or inaccurate information between various products.

I also think you concerns are valid bc these discussions can get out of context real quick. I just don't think we passed that line yet.

 

[Timcognito]

I also think you concerns are valid bc these discussions can get out of context real quick. I just don't think we passed that line yet.

Maybe I risk not practicing what I preach by continuing here. Its nice to pick device close to the price range and link to some test results and explain why that is better option than the other stated device with its data. It seemed to me that it was drifting away to a "you don't understand what you are talking about" between two sub posters. I issue a second apology if I am wrong.

 

[Zapper]

You did not explain anything.



Amplifying PWM signal achieves nothing. PWM is a square wave modulation signal and modulation is independent of amplitude: It's normalized to 1, 0 or -1, that's it:

PWM amplitude can be 0.1V or 100V, (0.1V = 1 or 100V = 1) it makes no difference to the actual analog signal produced with it.

Stereo amplification is pure analog signal modification, therefore amplifier = analog. There can't be such a thing as a "fully digital analog".

PWM as used in class-D is usually unipolar: 0 or 1. PWM means pulse width modulated, and that modulation can be generated by analog or digital means. Let's say you wanted to generate a PWM pulse with 16-bit resolution. You could take a very high frequency clock signal and divide it digitally by 2^16 = 65,536. Now you would take a programmable 16 bit counter, where the 16-bit input word would determine how many high frequency clock cycles are counted, from 0 to 65,535. The output of the counter goes high for the number of bits counted. If the input = 0, the output stays low. If input=1, it goes high for 1 bit and low for 65,534, etc until if the input = 65,535, the output stays on continuously. By this means you have made a PWM signal.

The output PWM signal, although it is produced by digital circuitry is no longer a digital signal, because it encodes a 16-bit value on one wire, not just a 0 or 1.

This PWM signal then drives the level shifters and amplifiers needed to generate the gate voltage of the NMOS power FETs used to switch the power output between its high and low states. This circuitry is considered analog, not digital, because it involves the transformation of the PWM input signal into the voltages and currents necessary to produce a high power output. So "Full Digital Amp" is a bit of a misnomer.

The FDA does other parts of the amplification process in the digital realm. The feedback circuits and the signal processing required in any negative feedback system to adjust amplitude and phases to ensure loop stability is done primarily or exclusively in the digital domain. Some FDAs also include ADCs to provide post filter feedback, which provides a more accurate output with less load dependency and distortion.

 

[TonyJZX]

the a30 has a operational peculiarity where you can have coax digital or you can have stereo rca input but not both

for many not such a big deal but its kind of a wonky deal if you must use both

 

[Hapo]

...because China...

 

[cyp]

Wow thanks guys for all the details and the constructive debate. I must admit I still didn't entirely get the differences between FDA and class D amps but if we say FDAs are an even better fit than class D amps for digital content then it's all I need to know from a user perspective...

For reference here are the details as of why the USB entry of the A30 is not as good as the optical or RCA ones
https://audiosciencereview.com/foru...oxjie-a30-amplifier-review.17547/post-1001769

 

[voodooless]

Wow thanks guys for all the details and the constructive debate. I must admit I still didn't entirely get the differences between FDA and class D amps but if we say FDAs are an even better fit than class D amps for digital content then it's all I need to know from a user perspective...

It’s isn’t really if you look at similar prices components. The Loxije A30 is a lot cheaper.

For reference here are the details as of why the USB entry of the A30 is not as good as the optical or RCA ones
https://audiosciencereview.com/foru...oxjie-a30-amplifier-review.17547/post-1001769

Like I said, don’t worry about it.

 

[cyp]

It’s isn’t really if you look at similar prices components. The Loxije A30 is a lot cheaper.

Like I said, don’t worry about it.

Do you often use the USB entry ? Do you notice any difference with the optical one with another DAC (and which DAC, audiophile grade ?)

 

[cyp]

Here another example of the Realtek "weakness"

Post in thread 'loxjie a30 usb input sound worse than analog in (SOLVED)'
https://audiosciencereview.com/foru...orse-than-analog-in-solved.39731/post-1400593


Hence I'm evaluating alternatives to make an informed decision

 

[voodooless]

Do you often use the USB entry ? Do you notice any difference with the optical one with another DAC (and which DAC, audiophile grade ?)

I always use USB. It's fine. The DAC is not the limiting factor if this board, the amps and analog signal processor are.

Here another example of the Realtek "weakness"

Post in thread 'loxjie a30 usb input sound worse than analog in (SOLVED)'
https://audiosciencereview.com/foru...orse-than-analog-in-solved.39731/post-1400593

I don't have Windows, use MacOS. The weakness is really Microsoft incapable of delivering driverless USB audio for decades.