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Aiyima A07 Max Amplifier Review

Rate this amplifier:

  • 1. Poor (headless panther)

    Votes: 37 12.2%
  • 2. Not terrible (postman panther)

    Votes: 126 41.6%
  • 3. Fine (happy panther)

    Votes: 104 34.3%
  • 4. Great (golfing panther)

    Votes: 36 11.9%

  • Total voters
    303
Whether audible depends on many factors. Chesky has some tracks on one or two discs that attempt to demonstrate any audible effects of inverted polarity.

BUT, the first graph of nearly every amplifier review here seems to show the output in absolute time (that bottom axis is time). Any inverting amplifier should show an inversion of this output signal, unless an inversion is being performed on the input signal and we're not being told (seems unlikely).

Not if (as I assume) it works like an oscilloscope - in which case it is triggering on the rising edge and this will hide any inversion. Time on the x axis is from the trigger point.
 
Not if (as I assume) it works like an oscilloscope - in which case it is triggering on the rising edge and this will hide any inversion. Time on the x axis is from the trigger point.

It would seem odd then that the y-axis would be labelled "instantaneous level."
 
All of Amir's 1 kHz measurement "dashboard" have sine waves rising at 0 V at t = 0 (at least for the triggered channel). This means the waveform view is just like a standard triggered oscilloscope view. If the dashboard waveform view is truly "instantaneous" *, the starting point of the waveform will be random, which will depend on the timing of the data acquisition.

* It cannot be truly "instantaneous" in the literal meaning of the word anyway as it takes time for data acquisition, data transfer from the AP to the computer, processing, and display.
 
All of Amir's 1 kHz measurement "dashboard" have sine waves rising at 0 V at t = 0 (at least for the triggered channel). This means the waveform view is just like a standard triggered oscilloscope view. If the dashboard waveform view is truly "instantaneous" *, the starting point of the waveform will be random, which will depend on the timing of the data acquisition.

* It cannot be truly "instantaneous" in the literal meaning of the word anyway as it takes time for data acquisition, data transfer from the AP to the computer, processing, and display.

Then what do you imagine "instantaneous" means in this context?

I'd be very surprised to learn that a graph showing "instantaneous output" would fail to show an inversion.
 
Then what do you imagine "instantaneous" means in this context?
Actual level at that time (instant) in the waveform - as distinct from (say) RMS.
 
After a thorough inspection by our engineers, we confirm that the speaker terminals of the A07 Max are functioning normally, and the product itself has shown no issues. We suspect that the abnormal behavior may be due to the speaker polarity being reversed on the customer’s end. Should you have any further questions, please do not hesitate to contact [email protected].
 
Just picked one of these up for my office system, £35 including the 48v power supply; seems like a bargain!
 
can you call them French-Fi?
 
So if I read the numbers correctly, if I wanted to use a single channel in stereo mode for a transducer (4ohms) that should not be fed more than 150W, then even with the 48v 5A power, I can run this Aiyima at 100% and be within that transducer limit, right?
Probably I will end up running 4 of them and setting the Aiyima in bridge mode.
 
So, Amir got a defective unit that caused channel unbalance, it's not a real issue? Does anyone have the power versus distortion data for 8Ohms in bridge mono mode with stock power supply (36v6a)?
 
I recently got a second Aiyima A07 MAX to try using as monoblocks. Initially, I set up with direct patching from a cd deck into the amps, and found that the volume pots on both were pretty unusable for playing at low volumes. There is no control at all below the 9 o'clock pot position. Fortunately, I have a well-made passive preamp, and with that inserted and the amp volume knobs set to 3 o'clock or max, I get good volume control via the preamp pot.

For anyone else using the A07 MAX, do be aware that the pot on the amp is very poor at low volumes, similar to the recent issue with the Fosi P4 preamp. These inexpensive pots are one drawback of these less-expensive products, and I hope there is the ability for the overseas makers to spec better quality pots (ALPS, etc.) in the future.

With a quality powered or passive preamp in the chain to control volume, the A07 MAX works very well as monoblocks.

@AIYIMA You might take note of this issue and give us your thoughts re ability to get better main volume pots in future products, similar to what you have done with other internal components? Particularly when the A07 MAX is used in stereo mode with direct patching to a source, lower volume control is very compromised.
IMG_7728.JPEG
 
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