This is a review and detailed measurements of Musiland MU2 Plus DAC and portable headphone amplifier. It is on kind loan from a member. I am having trouble finding the company's website. It is not sold broadly but where I find it, it seems to cost $70.
The Mu2 Plus is featherweight but manages to have a bit of luxury feel to it with the color selection and sturdy metal build:
The controls have a nice, positive tactile feel although I could not get the volume adjustments to take in every press. With no indicator, it is a bit hard to know if you have pressed the buttons enough or not.
The flat ribbon cable is quite flexible which is nice but I wonder about its longevity. It is also a shame that it is not color matched to the rest of the unit.
Overall, the Musiland MU2 Plus leaves a positive impression in the land and to the eye.
The MU2 Plus is plug-and-play compatible with Windows 10 Creators Edition. I did not try to get it working with my phone but I am assuming it works.
Measurements
My first attempt at measuring the MU2 Plus showed that using my ASIO wrapper API was truncating 24 bit audio samples to 16. So I played my test tone through Roon which worked fine and gave these nice results:
SINAD (signal over noise and distortion) is very good at 107 dB. This puts the MU2 Plus solidly in tier 2 performance of all DACs tested regardless of price and size:
Admittedly, the output is a bit anemic at 1.7 volt (we like to see 2 volts). Still, performance is limited by the second harmonic at -110 dB which is very nice.
Linearity, jitter and dynamic range tests unfortunately generated erroneous results due to truncation to 16 bits using ASIO interface. So let's see how the MU2 Plus does in power department starting with 300 ohm load:
There is only downward sloping graph meaning that the output never gets distorted. We simply run out of voltage to produce more power than 10 milliwatts. As shown on the graph, this is similar power to low-gain mode of Topping DX3 Pro low gain mode.
Switching to more brutal 33 ohm load which demands current, puts the MU2 Plus on its back, generating distortion this time:
There is a rise in distortion at just 4 milliwatts and then clipping at a much healthier level of 45 milliwatts. This time there is no competition for desktop products even in their low gain setting.
Putting these power ratings in context, we see this:
The MU2 Plus finishes ahead of all the other dongles tests at 33 ohm and almost so at 300 ohm, losing by just one milliwatt to Dragonfly red.
Output impedance was a very good and low, 1.2 ohm:
This means you should not worry about the frequency response of the headphone to be modified by the MU2 Plus.
Power consumption was good but not class leading:
The unit gets a bit warm to touch so clearly it is dissipating some power. I will need to fill out this table more with other dongles tested.
Listening Tests
I must say, I had low expectations going into subjective evaluation but I was proven wrong. With Sennheiser HD-650 at max volume, sound quality was very nice. Granted, there was no headroom as you almost had to operate it all the time at max volume but still, it sounded quite acceptable. This is definitely not a give in these ultraportable DAC and headphone amps.
Switching to Hifiman HE-400i was even more satisfying. I could now listen at one or two notches below max. Fidelity was excellent and music quite enjoyable.
I can only conclude that the MU2 Plus is able to handle momentary peaks in music better than its steady state power measurements show. To wit, on one of the bass heavy tracks with Dragonfly Red would constantly mute on each bass note but not the MU2 Plus. It rode through them as if there were not there.
Conclusions
The Musiland MU2 Plus may seem like one of countless portable DAC and amps but it distinguishes itself in testing with class leading distortion figures as a DAC. It also generates good bit more power than most dongles.
The listening tests showed that the good numbers translate into goot sound, perhaps even more so than the power numbers indicate. There is a level of fidelity there that is kind of surprising.
Given the reasonable price of $70, I am going to put the Musiland MU2 Plus on my recommended list.
------------
As always, questions, comments, recommendations, etc. are welcome.
Winter is the best time to eat white fleshed fish. In winter time the fish put on more fat making what is normally a lean fish, more oily and hence tasty! this is most important when you eat it raw, in sushi form. So please, donate some money so that I can afford to go and get some tasty sushi!
Patreon: https://www.patreon.com/audiosciencereview), or
upgrading your membership here though Paypal (https://audiosciencereview.com/foru...eview-and-measurements.2164/page-3#post-59054).
The Mu2 Plus is featherweight but manages to have a bit of luxury feel to it with the color selection and sturdy metal build:
The controls have a nice, positive tactile feel although I could not get the volume adjustments to take in every press. With no indicator, it is a bit hard to know if you have pressed the buttons enough or not.
The flat ribbon cable is quite flexible which is nice but I wonder about its longevity. It is also a shame that it is not color matched to the rest of the unit.
Overall, the Musiland MU2 Plus leaves a positive impression in the land and to the eye.
The MU2 Plus is plug-and-play compatible with Windows 10 Creators Edition. I did not try to get it working with my phone but I am assuming it works.
Measurements
My first attempt at measuring the MU2 Plus showed that using my ASIO wrapper API was truncating 24 bit audio samples to 16. So I played my test tone through Roon which worked fine and gave these nice results:
SINAD (signal over noise and distortion) is very good at 107 dB. This puts the MU2 Plus solidly in tier 2 performance of all DACs tested regardless of price and size:
Admittedly, the output is a bit anemic at 1.7 volt (we like to see 2 volts). Still, performance is limited by the second harmonic at -110 dB which is very nice.
Linearity, jitter and dynamic range tests unfortunately generated erroneous results due to truncation to 16 bits using ASIO interface. So let's see how the MU2 Plus does in power department starting with 300 ohm load:
There is only downward sloping graph meaning that the output never gets distorted. We simply run out of voltage to produce more power than 10 milliwatts. As shown on the graph, this is similar power to low-gain mode of Topping DX3 Pro low gain mode.
Switching to more brutal 33 ohm load which demands current, puts the MU2 Plus on its back, generating distortion this time:
There is a rise in distortion at just 4 milliwatts and then clipping at a much healthier level of 45 milliwatts. This time there is no competition for desktop products even in their low gain setting.
Putting these power ratings in context, we see this:
The MU2 Plus finishes ahead of all the other dongles tests at 33 ohm and almost so at 300 ohm, losing by just one milliwatt to Dragonfly red.
Output impedance was a very good and low, 1.2 ohm:
This means you should not worry about the frequency response of the headphone to be modified by the MU2 Plus.
Power consumption was good but not class leading:
The unit gets a bit warm to touch so clearly it is dissipating some power. I will need to fill out this table more with other dongles tested.
Listening Tests
I must say, I had low expectations going into subjective evaluation but I was proven wrong. With Sennheiser HD-650 at max volume, sound quality was very nice. Granted, there was no headroom as you almost had to operate it all the time at max volume but still, it sounded quite acceptable. This is definitely not a give in these ultraportable DAC and headphone amps.
Switching to Hifiman HE-400i was even more satisfying. I could now listen at one or two notches below max. Fidelity was excellent and music quite enjoyable.
I can only conclude that the MU2 Plus is able to handle momentary peaks in music better than its steady state power measurements show. To wit, on one of the bass heavy tracks with Dragonfly Red would constantly mute on each bass note but not the MU2 Plus. It rode through them as if there were not there.
Conclusions
The Musiland MU2 Plus may seem like one of countless portable DAC and amps but it distinguishes itself in testing with class leading distortion figures as a DAC. It also generates good bit more power than most dongles.
The listening tests showed that the good numbers translate into goot sound, perhaps even more so than the power numbers indicate. There is a level of fidelity there that is kind of surprising.
Given the reasonable price of $70, I am going to put the Musiland MU2 Plus on my recommended list.
------------
As always, questions, comments, recommendations, etc. are welcome.
Winter is the best time to eat white fleshed fish. In winter time the fish put on more fat making what is normally a lean fish, more oily and hence tasty! this is most important when you eat it raw, in sushi form. So please, donate some money so that I can afford to go and get some tasty sushi!
Patreon: https://www.patreon.com/audiosciencereview), or
upgrading your membership here though Paypal (https://audiosciencereview.com/foru...eview-and-measurements.2164/page-3#post-59054).