This is a review and detailed measurements of the Optoma NuForce DAC80 DAC. It is on kind loan from a member who has been patiently waiting for it from November of last year! 
This a rather older DAC (in "DAC years") having been introduced back in 2016 with a retail cost of USD $549. Massdrop put this up for sale in 2017 for USD $331 which is how the owner acquired it.
The box is decent enough from the outside:
To turn on the unit you have to push the volume control in. Doing the same while on selects the input. Turning off requires holding down the button. All standard methods but not the indicator of which input. As you see, there is some attempt at using an array of LEDs to indicate the input by a letter. Alas, these are pretty dim and hard to see in bright light. It is a bit of differentiation which I don't think is worth the cost.
The volume control is rather strange feeling. It has limits so it is an analog control but has a loose feeling at the same time. It is certainly something that doesn't inspire confidence or say this is an expensive product.
At this price range I expect to see balanced/XLR outputs but there are none. You only have RCA output and the standard USB, S/PDIF and Toslink optical inputs.
Power supply is inside the unit which is nice with respect to removing clutter and wires coming out of the unit.
I plugged the unit into my Windows 10 post Creators Edition and it was recognized but when I tried to use it with ASIO4ALL ASIO wrapper, it showed clear sign of data being truncated to 16 bits (SINAD limited to 96 dB and 100 Hz spikes in spectrum). Downloaded the drivers which nice had an ASIO interface and control panel. Alas, things went downhill from there. SINAD shrunk down to 80 dB and at every move, I would get a different FFT spectrum display with very strange noise and distortion products. No amount of messing with the settings in the control panel did anything useful to remedy this.
So I fired up Roon media player and told it to use the WSAPI bit-exact interface to DAC80. To my pleasant surprise, that worked and SINAD shot way up (see measurement section). Testing with Roon as the output program though is very limiting to I tried ASIO4ALL again in Audio Precision interface and bam, it worked too generating the same good results!
Clearly the ASIO driver as provided is broken. And possibly some other things seeing how I could not get good performance initially out of it.
More issues await us as we get into measurements....
Measurements
The output from DAC80 is variable and goes up to 3.5 volts or so. Nominal output of unbalanced/RCA DACs should be 2 volts so for fairness, I tried to set that using the volume control. This proved very challenging. The volume control would either make no difference or all of a sudden jump past the 2 volt level. Clearly the control is either implemented wrong or is broken in my sample unit. After much playing, we got lucky and got the 2 volt output. Here is what the dashboard looked like then:
Note that the THD+N results are much better than what NuForce itself advertises! The number they have is what you get when the signal is truncated to 16 bits. Seems like they were testing the unit incorrectly themselves!
The SINAD (signal over noise and distortion) puts the DAC80 at the bottom of our tier 2 performance with respect to distortion and noise:
Dynamic range measurements show the same mistaken specification:
I ran the linearity test but by mistake, I selected the DAC80's own ASIO interface (in red) before running it again with ASIO4ALL wrapper:
You can see that the native ASIO driver is doing major damage to the bits. Fortunately the ASIO4ALL does much better, showing near transparency for CD's 16-bit music.
Jitter test didn't show anything upsetting:
Yes there are some power supply components causing jitter sidebands hugging our main tone at 12 kHz but those are perceptually "masked."
Noise level is higher though and that shows up in IMD test:
My template for the test happened to have the results of its spin-off company, NuPrime's uDSD. As we see the performance is essentially the same except that the DAC80 starts to distortion more. Considering that uDSD costs just $179s, that is very poor showing on behalf of DAC80. Clearly much better performance can be had as shown by Topping DX3 Pro in red.
I usually tell you all that the multi-tone test doesn't show anything we don't already see in other tests but here, I had to eat my words:
What the heck is going on here??? Noise floor (bottoms of the curves) has risen a whopping 60 dB! This is stunning amount of "noise modulation."
Worst yet, the test would NOT run with USB. Selecting 192 kHz sampling as required for this test would generate no signal. S/PDIF however worked and gave us the above measurements. This is kind of amusing because the manual says to set the rate permanently to 192 kHz in Windows:
Tried to troubleshoot this a bit by measuring the spectrum of a 1 kHz tone at 48.1 kHz and 192 kHz and got these strange results:
There are those tall spikes in blue but they are only there at the lower sampling rate of 48 kHz. They vanish at 192 kHz.
Conclusions
The NuForce DAC80 has produced some of the strangest measurements and experiences I have had with a DAC. The owner likewise had complained about strange problems such as distortion during initial power on. Clearly the DAC80 has not been put through any proper design/engineering verification. The buggy ASIO driver issues are readily apparent even with the most rudimentary measurement system. What is going on with much elevated noise floor by playing 32-tones at 192 kHz is hard to explain. Why USB does not work 192 Khz should have been another obvious problem.
Yes, there are vagaries with connecting DACs to Windows machines but these problems well exceed that.
I went and searched for reviews of DAC80 and found a couple. Both were subjective reviews even though the first comes a place that is objectively oriented (audioholics) but apparently not with DACs: https://www.audioholics.com/gadget-reviews/optoma-nuforce-dac80-review/sound-quality
His summary is such:
How wrong we can be when just performing ad-hoc listening tests without proper control and objective data. Very wrong in this case.
Needless to say, there is no way I can recommend the Optoma NuForce DAC80. Even if it performed perfectly, it is very feature poor at this price range let alone with the array of software and hardware design issues/bugs. Clearly the company doesn't believe in design and engineering verification to have let this product in the wild in this manner. A product like SMSL SU-8 (version 2) runs circles around it for half the price.
------------
As always, questions, comments, recommendations, etc. are welcome.
They say you should save money for a rainy day. It rains for about 6 months here so I need plenty of money!!! 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).
This a rather older DAC (in "DAC years") having been introduced back in 2016 with a retail cost of USD $549. Massdrop put this up for sale in 2017 for USD $331 which is how the owner acquired it.The box is decent enough from the outside:
To turn on the unit you have to push the volume control in. Doing the same while on selects the input. Turning off requires holding down the button. All standard methods but not the indicator of which input. As you see, there is some attempt at using an array of LEDs to indicate the input by a letter. Alas, these are pretty dim and hard to see in bright light. It is a bit of differentiation which I don't think is worth the cost.
The volume control is rather strange feeling. It has limits so it is an analog control but has a loose feeling at the same time. It is certainly something that doesn't inspire confidence or say this is an expensive product.
At this price range I expect to see balanced/XLR outputs but there are none. You only have RCA output and the standard USB, S/PDIF and Toslink optical inputs.
Power supply is inside the unit which is nice with respect to removing clutter and wires coming out of the unit.
I plugged the unit into my Windows 10 post Creators Edition and it was recognized but when I tried to use it with ASIO4ALL ASIO wrapper, it showed clear sign of data being truncated to 16 bits (SINAD limited to 96 dB and 100 Hz spikes in spectrum). Downloaded the drivers which nice had an ASIO interface and control panel. Alas, things went downhill from there. SINAD shrunk down to 80 dB and at every move, I would get a different FFT spectrum display with very strange noise and distortion products. No amount of messing with the settings in the control panel did anything useful to remedy this.
So I fired up Roon media player and told it to use the WSAPI bit-exact interface to DAC80. To my pleasant surprise, that worked and SINAD shot way up (see measurement section). Testing with Roon as the output program though is very limiting to I tried ASIO4ALL again in Audio Precision interface and bam, it worked too generating the same good results!
Clearly the ASIO driver as provided is broken. And possibly some other things seeing how I could not get good performance initially out of it.
More issues await us as we get into measurements....
Measurements
The output from DAC80 is variable and goes up to 3.5 volts or so. Nominal output of unbalanced/RCA DACs should be 2 volts so for fairness, I tried to set that using the volume control. This proved very challenging. The volume control would either make no difference or all of a sudden jump past the 2 volt level. Clearly the control is either implemented wrong or is broken in my sample unit. After much playing, we got lucky and got the 2 volt output. Here is what the dashboard looked like then:
Note that the THD+N results are much better than what NuForce itself advertises! The number they have is what you get when the signal is truncated to 16 bits. Seems like they were testing the unit incorrectly themselves!
The SINAD (signal over noise and distortion) puts the DAC80 at the bottom of our tier 2 performance with respect to distortion and noise:
Dynamic range measurements show the same mistaken specification:
I ran the linearity test but by mistake, I selected the DAC80's own ASIO interface (in red) before running it again with ASIO4ALL wrapper:
You can see that the native ASIO driver is doing major damage to the bits. Fortunately the ASIO4ALL does much better, showing near transparency for CD's 16-bit music.
Jitter test didn't show anything upsetting:
Yes there are some power supply components causing jitter sidebands hugging our main tone at 12 kHz but those are perceptually "masked."
Noise level is higher though and that shows up in IMD test:
My template for the test happened to have the results of its spin-off company, NuPrime's uDSD. As we see the performance is essentially the same except that the DAC80 starts to distortion more. Considering that uDSD costs just $179s, that is very poor showing on behalf of DAC80. Clearly much better performance can be had as shown by Topping DX3 Pro in red.
I usually tell you all that the multi-tone test doesn't show anything we don't already see in other tests but here, I had to eat my words:
What the heck is going on here??? Noise floor (bottoms of the curves) has risen a whopping 60 dB! This is stunning amount of "noise modulation."
Worst yet, the test would NOT run with USB. Selecting 192 kHz sampling as required for this test would generate no signal. S/PDIF however worked and gave us the above measurements. This is kind of amusing because the manual says to set the rate permanently to 192 kHz in Windows:
Tried to troubleshoot this a bit by measuring the spectrum of a 1 kHz tone at 48.1 kHz and 192 kHz and got these strange results:
There are those tall spikes in blue but they are only there at the lower sampling rate of 48 kHz. They vanish at 192 kHz.
Conclusions
The NuForce DAC80 has produced some of the strangest measurements and experiences I have had with a DAC. The owner likewise had complained about strange problems such as distortion during initial power on. Clearly the DAC80 has not been put through any proper design/engineering verification. The buggy ASIO driver issues are readily apparent even with the most rudimentary measurement system. What is going on with much elevated noise floor by playing 32-tones at 192 kHz is hard to explain. Why USB does not work 192 Khz should have been another obvious problem.
Yes, there are vagaries with connecting DACs to Windows machines but these problems well exceed that.
I went and searched for reviews of DAC80 and found a couple. Both were subjective reviews even though the first comes a place that is objectively oriented (audioholics) but apparently not with DACs: https://www.audioholics.com/gadget-reviews/optoma-nuforce-dac80-review/sound-quality
His summary is such:
How wrong we can be when just performing ad-hoc listening tests without proper control and objective data. Very wrong in this case.
Needless to say, there is no way I can recommend the Optoma NuForce DAC80. Even if it performed perfectly, it is very feature poor at this price range let alone with the array of software and hardware design issues/bugs. Clearly the company doesn't believe in design and engineering verification to have let this product in the wild in this manner. A product like SMSL SU-8 (version 2) runs circles around it for half the price.
------------
As always, questions, comments, recommendations, etc. are welcome.
They say you should save money for a rainy day. It rains for about 6 months here so I need plenty of money!!! 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).
