This is a review and detailed measurements of the Music Hall pa2.2 ADC (digitizer) USB Phono Stage. It is on kind loan from a member and costs US $449.
Controls are easy to use, being just toggle switches. An external adapter is provided for power:
Nice to see independent input for general digitization. You also have independent inputs for moving coil/magnet. I only tested the unit as digitizer. Not sure if line out is an analog pass through or for output from USB input (did not test this aspect).
There were no drivers on the company website so I used my ASIO4ALL emulation over Windows class driver.
Music Hall pa2.2 Measurements
I started out just testing it as a line input. The input saturated rather early at just 1.5 volt input:
It is not going to win any awards as an ADC, finishing near last with all the distortion it has:
But that is not the worst problem. That title belongs to timing mismatch between the two channels. Left and right sine waves should be on top of each other and they are not. If I increase the test frequency to 20 kHz, the delay mismatch becomes much closer to the wavelength of the tone:
In other words, by the time you get to 20 kHz, the two channels will be completely out of phase! This could be a firmware issue and fixable. As is, it makes the rest of the review academic but let's test a bit more in case they fix this:
Company has rather detailed specs and shows an incredible value of 120 dB which would be state of the art. Needless to say, we are not even in the same planet. Maybe that is a chip spec.
ADC input bandwidth is a bit above audible band:
192 kHz did nothing different from 96 kHz.
Let's switch to MM phono input:
Strange that the low frequency noise is flat. SINAD of 45 dB would tie it for the worst phono stage ever tested! And our channel mismatch as far as timing remains.
RIAA equalization is respectable:
Headroom is not, and strangely, is worse at lower frequencies:
Digging in, we see that it is the negative supply that runs out:
I lost the will to live, I mean to test more....
Conclusions
I expect competent implementation from Music Hall. The pa2.2 bucks that trend, demonstrating clear implementation bug and performance is quite sub-par. Other than good RIAA equalization, I can't think of anything positive about it. If it were a $150 device, we could cut it some slack but at nearly $500? No way. You can buy an audio interface with a phono stage for much less money and far better performance.
I can't recommend the Music Hall pa2.2. I hope the company at least fixes the timing problem.
------------
As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
Controls are easy to use, being just toggle switches. An external adapter is provided for power:
Nice to see independent input for general digitization. You also have independent inputs for moving coil/magnet. I only tested the unit as digitizer. Not sure if line out is an analog pass through or for output from USB input (did not test this aspect).
There were no drivers on the company website so I used my ASIO4ALL emulation over Windows class driver.
Music Hall pa2.2 Measurements
I started out just testing it as a line input. The input saturated rather early at just 1.5 volt input:
It is not going to win any awards as an ADC, finishing near last with all the distortion it has:
But that is not the worst problem. That title belongs to timing mismatch between the two channels. Left and right sine waves should be on top of each other and they are not. If I increase the test frequency to 20 kHz, the delay mismatch becomes much closer to the wavelength of the tone:
In other words, by the time you get to 20 kHz, the two channels will be completely out of phase! This could be a firmware issue and fixable. As is, it makes the rest of the review academic but let's test a bit more in case they fix this:
Company has rather detailed specs and shows an incredible value of 120 dB which would be state of the art. Needless to say, we are not even in the same planet. Maybe that is a chip spec.
ADC input bandwidth is a bit above audible band:
192 kHz did nothing different from 96 kHz.
Let's switch to MM phono input:
Strange that the low frequency noise is flat. SINAD of 45 dB would tie it for the worst phono stage ever tested! And our channel mismatch as far as timing remains.
RIAA equalization is respectable:
Headroom is not, and strangely, is worse at lower frequencies:
Digging in, we see that it is the negative supply that runs out:
I lost the will to live, I mean to test more....
Conclusions
I expect competent implementation from Music Hall. The pa2.2 bucks that trend, demonstrating clear implementation bug and performance is quite sub-par. Other than good RIAA equalization, I can't think of anything positive about it. If it were a $150 device, we could cut it some slack but at nearly $500? No way. You can buy an audio interface with a phono stage for much less money and far better performance.
I can't recommend the Music Hall pa2.2. I hope the company at least fixes the timing problem.
------------
As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
