This is a review and detailed measurements of the LH Labs GO2Pro Infinity portable DAC and headphone amplifier. It is on kind loan from a member. It costs USD $480 including a 20% discount as of this writing. So full retain price is a whopping $600!
I tested the regular GO2Pro version a while back but it was with my less standardized tests.
The GO2Pro Infinity is a chunky unit the size of a mobile phone but much thicker and heavier:
I like that the sides are chamfered which makes them fit the hand better and poke you less.
The color and graphics also give the unit a somewhat luxury look, separating it from the crowd of products in this category (battery operated headphone DAC+amp).
There are separate USB jacks for data and charging. I wish the data one could do both for desktop use.
The on/off switch is a stiff slider which I guess is good so it won't accidentally turn on by itself and drain the battery.
I was not a fan of the user interface in the original version and that continues with this unit. I mean how are you going to decipher such controls?
Not only are the legends almost invisible, the LEDs change color to indicate different things. Fortunately you will mostly be dealing with the volume controls on the side which do the job with decent feel.
There are both "balanced" and unbalanced headphone jacks. Alas, they use the same sized 3.5 mm jack. Most other companies use 2.5mm for the balanced to keep one from accidently plugging the headphone into the wrong jack.
Measurements
As with my test of other combo DAC and Amps, I adjusted the volume as close to 2 volts as I could for the dashboard measurement that emphasize the DAC performance:
OK, not awful but not that respectable either. SINAD (signal over distortion and noise) barely clears the hurdle to land in tier 3 of DACs tested:
In comparison, the direct competitor to the GO2Pro, the Topping NX4 DS clocks at 104. That is a massive 13 dB improvement in noise and distortion.
Dynamic range is good for this class of device and meets spec:
Intermodulation distortion versus level repeats the story of THD+N in the dashboard:
Even though I have kept the output below max at 2 volts, distortion starts to set in around -15 dB and keeps climbing. The output buffer is not as transparent as it could be.
Ditto for our 32-tone test signal:
Jitter and linearity through are very competitive and good:
Setting the volume control to max and measuring power versus distortion+noise using 300 ohm load we get:
37 milliwatts is respectable and beats the low gain of our desktop reference (Topping DX3 Pro).
Switching to the other extreme load at 33 ohm we get:
There is again healthy amount of power here at 320 milliwatts.
My balanced load is at 50 ohm so here it is in both modes of operation:
We see that power doubles using balanced output, delivering desktop class amount of energy to such headphones.
Output impedance is comfortably low at just 0.8 ohm:
This should allow GO2Pro Infinity to drive any headphone without impacting its frequency response.
Listening Tests
As usual, I start my testing with Sennheiser HD650 headphones. Here, once I pushed the volume/gain to max (top LED becomes white), there was ample power for just about anything I played. Comfortable level was a notch or two below max. I imagine if you rewired your HD-650 to be balanced, you would get even more headroom.
Somehow the experience with Hifiman HE-400i was not as rewarding. Not sure if this was my mood today , or performance of device. Of course there is plenty of power so no worries here.
Conclusions
As a DAC, the LH Labs GO2Pro Infinity edition struggles to deliver good performance. Its output stage distorts early, landing the unit pretty low compared to its competition despite its astronomical price. The headphone output though makes up for that with lots of power, especially if you use its balanced output.
The problem facing GO2Pro is performance/price ratio. On that front, the Topping NX4 DSD runs circles around it due to it costing just USD $159 with prime shipping from Amazon. That is 1/4 of the retail price of the GO2 Pro. Is there enough of a luxury feel here to overcome that massive price gap? I don't think so but you may think otherwise.
------------
As always, questions, comments, recommendations, etc. are welcome.
Crap! Snow came back today. Need money to buy a second snow shovel. Please consider donating funds using:
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).
I tested the regular GO2Pro version a while back but it was with my less standardized tests.
The GO2Pro Infinity is a chunky unit the size of a mobile phone but much thicker and heavier:
I like that the sides are chamfered which makes them fit the hand better and poke you less.
The color and graphics also give the unit a somewhat luxury look, separating it from the crowd of products in this category (battery operated headphone DAC+amp).
There are separate USB jacks for data and charging. I wish the data one could do both for desktop use.
The on/off switch is a stiff slider which I guess is good so it won't accidentally turn on by itself and drain the battery.
I was not a fan of the user interface in the original version and that continues with this unit. I mean how are you going to decipher such controls?
There are both "balanced" and unbalanced headphone jacks. Alas, they use the same sized 3.5 mm jack. Most other companies use 2.5mm for the balanced to keep one from accidently plugging the headphone into the wrong jack.
Measurements
As with my test of other combo DAC and Amps, I adjusted the volume as close to 2 volts as I could for the dashboard measurement that emphasize the DAC performance:
OK, not awful but not that respectable either. SINAD (signal over distortion and noise) barely clears the hurdle to land in tier 3 of DACs tested:
In comparison, the direct competitor to the GO2Pro, the Topping NX4 DS clocks at 104. That is a massive 13 dB improvement in noise and distortion.
Dynamic range is good for this class of device and meets spec:
Intermodulation distortion versus level repeats the story of THD+N in the dashboard:
Even though I have kept the output below max at 2 volts, distortion starts to set in around -15 dB and keeps climbing. The output buffer is not as transparent as it could be.
Ditto for our 32-tone test signal:
Jitter and linearity through are very competitive and good:
Setting the volume control to max and measuring power versus distortion+noise using 300 ohm load we get:
37 milliwatts is respectable and beats the low gain of our desktop reference (Topping DX3 Pro).
Switching to the other extreme load at 33 ohm we get:
There is again healthy amount of power here at 320 milliwatts.
My balanced load is at 50 ohm so here it is in both modes of operation:
We see that power doubles using balanced output, delivering desktop class amount of energy to such headphones.
Output impedance is comfortably low at just 0.8 ohm:
This should allow GO2Pro Infinity to drive any headphone without impacting its frequency response.
Listening Tests
As usual, I start my testing with Sennheiser HD650 headphones. Here, once I pushed the volume/gain to max (top LED becomes white), there was ample power for just about anything I played. Comfortable level was a notch or two below max. I imagine if you rewired your HD-650 to be balanced, you would get even more headroom.
Somehow the experience with Hifiman HE-400i was not as rewarding. Not sure if this was my mood today , or performance of device. Of course there is plenty of power so no worries here.
Conclusions
As a DAC, the LH Labs GO2Pro Infinity edition struggles to deliver good performance. Its output stage distorts early, landing the unit pretty low compared to its competition despite its astronomical price. The headphone output though makes up for that with lots of power, especially if you use its balanced output.
The problem facing GO2Pro is performance/price ratio. On that front, the Topping NX4 DSD runs circles around it due to it costing just USD $159 with prime shipping from Amazon. That is 1/4 of the retail price of the GO2 Pro. Is there enough of a luxury feel here to overcome that massive price gap? I don't think so but you may think otherwise.
------------
As always, questions, comments, recommendations, etc. are welcome.
Crap! Snow came back today. Need money to buy a second snow shovel. Please consider donating funds using:
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).