Articles, Reviews and Measurements of Audio Products
Review and Measurements of NuPrime uDSD DAC/AMP
This is a review and detailed measurements of NuPrime uDSD DAC and headphone amplifier. I purchased this summer of last year from Amazon for USD $179 including Prime shipping.
This is a cute and very sturdy portable amp and dac:
It has really beefy RCA connectors in the back, the likes of which I have only seen in Khadas Tone Board. They would feel at home in gear retailing for a lot of money.
The enclosure is metal and while it is sturdy, cables can pull it around some.
Let's get into measurements and see if she is worth the extra premium over cheaper offerings.
Measurements
As usual I start with Dashboard measurements and there, I was initially very unimpressed with the results:
Remembering that some devices deteriorate in performance when their volume control is at max -- even though I am testing RCA out -- I lowered the volume to min and the situation improved significantly...
This is a cute and very sturdy portable amp and dac:
It has really beefy RCA connectors in the back, the likes of which I have only seen in Khadas Tone Board. They would feel at home in gear retailing for a lot of money.
The enclosure is metal and while it is sturdy, cables can pull it around some.
Let's get into measurements and see if she is worth the extra premium over cheaper offerings.
Measurements
As usual I start with Dashboard measurements and there, I was initially very unimpressed with the results:
Remembering that some devices deteriorate in performance when their volume control is at max -- even though I am testing RCA out -- I lowered the volume to min and the situation improved significantly...
Review and Measurements of Linn Akurate DSM DAC/Streamer
This is a (performance) review and detailed measurements of the Linn Akurate DSM DAC and networked streamer. A local member kindly brought it over to our house to measure. It retails for .... get ready for it... USD $10,250. Yes, we are moving up in the world!
Linn is a Scottish company that has a long tradition/history among audiophiles although most of it earned through their legendary turntables than digital technology.
I had a lot of fun chatting with the owner of it so forgot to take a picture of it. Here is the stock photo from Linn's site:
The unit is quite substantial and with luxury feel.
Due to shortness of time, I did not have a chance to play much with its functionality. I was pleased that it supported Roon Endpoint and I could stream full 24-bit, high sample rate content to it with equal performance to its S/PDIF input which I used for testing.
Why S/PDIF input? Oddly there is no USB input on Linn Akurate DSM...
Linn is a Scottish company that has a long tradition/history among audiophiles although most of it earned through their legendary turntables than digital technology.
I had a lot of fun chatting with the owner of it so forgot to take a picture of it. Here is the stock photo from Linn's site:
The unit is quite substantial and with luxury feel.
Due to shortness of time, I did not have a chance to play much with its functionality. I was pleased that it supported Roon Endpoint and I could stream full 24-bit, high sample rate content to it with equal performance to its S/PDIF input which I used for testing.
Why S/PDIF input? Oddly there is no USB input on Linn Akurate DSM...
Review and Measurements of Accuphase E-270 Amplifier
This is a review and detailed measurements of Accuphase E-270 Integrated Amplifier. It is on kind loan from our friends at Gig Harbor Audio. It is their demo unit so I have to return it on Tuesday. So if you need something else to be measured, ask right away! The E-270 was released in 2017 I think and retails for USD $5,000. This is not cheap by our normal standards but in high-end audio, this is a pretty reasonable price.
The industrial design of the unit seemingly has not changed from 1980s era with beautiful VU meters (with acceleration):
At 44 pounds, the unit is quite heavy for its capabilities. There is a massive transformer in the middle of the unit and the power amplifier modules with beefy heatsinks sit on either side. During my testing, I could not even get the unit to become warm let alone hot! It runs so comfortably that one thinks it is never going to stress out.
The...
The industrial design of the unit seemingly has not changed from 1980s era with beautiful VU meters (with acceleration):
At 44 pounds, the unit is quite heavy for its capabilities. There is a massive transformer in the middle of the unit and the power amplifier modules with beefy heatsinks sit on either side. During my testing, I could not even get the unit to become warm let alone hot! It runs so comfortably that one thinks it is never going to stress out.
The...
Review and Measurements of Onkyo M-282 Amp
This is a review and detailed measurements of Onkyo M-282 Power (speaker) amplifier. It is on kind loan from a member who bought it a few years ago but had not used it. Seems like it was just discontinued as I checked the price yesterday and it was being sold for $300 or so from Amazon. The suggested replacement by Amazon is lower power (75 versus 100 watts for M-282) but is also cheaper at $210.
The box is quite large but other than the left side that is weighted down by a transformer, it feels rather light:
The front looks slick and high quality.
The back has two pairs of RCA connectors: one for input and one for output. There is a switch to select auto-on with audio, 12 volt trigger, or always on which is the mode i used.
There is trim potentiometer in the back to set the input sensitivity. At first I left this in the default middle setting but that showed fair amount of channel mistmatch. So I set it to max and the two...
The box is quite large but other than the left side that is weighted down by a transformer, it feels rather light:
The front looks slick and high quality.
The back has two pairs of RCA connectors: one for input and one for output. There is a switch to select auto-on with audio, 12 volt trigger, or always on which is the mode i used.
There is trim potentiometer in the back to set the input sensitivity. At first I left this in the default middle setting but that showed fair amount of channel mistmatch. So I set it to max and the two...
Review and Measurements of KORG DS-DAC-100
This is a review and detailed measurements of the KORG DS-DAC-100 Balanced DAC and headphone amplifier. It is on kind loan from a member. It retails for USD $446 with free shipping from Amazon.
If you are not familiar with KORG, they are a Japanese company which has been producing professional audio products for years. They have a respectable reputation. Given that and high price of this unit, my expectations of fidelity was high.
Perhaps the most claim to fame of the KORG DS-DAC-100 is its very unusual industrial design, harkening to the science fiction modern style of 1960s:
In a word: it is adorable!
Note the spikes below that act as feet. With the bit of weight the unit has, you better careful in putting it on top of your precious wood desk or other surface that can scratch.
As I noted earlier, this DAC has balanced XLR outputs. But unusually at this price, it has no other inputs than USB. This is fine for me in...
If you are not familiar with KORG, they are a Japanese company which has been producing professional audio products for years. They have a respectable reputation. Given that and high price of this unit, my expectations of fidelity was high.
Perhaps the most claim to fame of the KORG DS-DAC-100 is its very unusual industrial design, harkening to the science fiction modern style of 1960s:
In a word: it is adorable!
Note the spikes below that act as feet. With the bit of weight the unit has, you better careful in putting it on top of your precious wood desk or other surface that can scratch.
As I noted earlier, this DAC has balanced XLR outputs. But unusually at this price, it has no other inputs than USB. This is fine for me in...
Review and Measurements of SMSL M10 DAC & Amp
This is a review and detailed measurements of SMSL M10 desktop DAC and headphone amplifier. It is on kind loan from a member. This is a "high-end" unit from SMSL and retails for USD $545 from Amazon including free Prime shipping.
As soon as you take out the M10 out of the box, you definitely get the feeling that this is one hefty unit. It is not as heavy as SMSL D-1 but it is up there with inclusion of a power supply and such. The display is also much larger than more budget oriented SMSL DACs and amps:
As you can see, the SMSL M10 sports both 1/4 inch headphone jack and XLR for "balanced" headphone output. You would need to select either one of these in the menu in addition to whether the headphone output is on or line out.
For output, we have both RCA and balanced XLR outputs which is really nice and expected in this price range.
Menus are pretty intuitive to follow with push of the power button and rotary knob. The...
As soon as you take out the M10 out of the box, you definitely get the feeling that this is one hefty unit. It is not as heavy as SMSL D-1 but it is up there with inclusion of a power supply and such. The display is also much larger than more budget oriented SMSL DACs and amps:
As you can see, the SMSL M10 sports both 1/4 inch headphone jack and XLR for "balanced" headphone output. You would need to select either one of these in the menu in addition to whether the headphone output is on or line out.
For output, we have both RCA and balanced XLR outputs which is really nice and expected in this price range.
Menus are pretty intuitive to follow with push of the power button and rotary knob. The...
Review and Measurements of Crown XLS 1502 Amp
This is a review and detailed measurements of the Crown XLS 1502 "PA" Power Amplifier. It is on a kind loan from a member who bought it new and drop shipped it to me. It retails for USD $349 including free Prime shipping from Amazon. At that price, it seems like an incredible value.
I have to say, while the unit looks industrial/military, it does not at all feel cheap. As expected it comes in 19 inch rack mount configuration but very shallow:
Not only do you get a high power amplifier with front graphical display and such, but also a built-in DSP. It is not a fancy subsystem but allows you to dial in crossovers and such which is very handy in live sound. At may company (Madrona Digital) we use a ton of Crown amps not for hifi applications but for music distribution in the home. The built-in DSPs come in handy for limiting the frequency range, max output, etc..
Unlike home units, the XLS 1502 has a built-in fan with tons of...
I have to say, while the unit looks industrial/military, it does not at all feel cheap. As expected it comes in 19 inch rack mount configuration but very shallow:
Not only do you get a high power amplifier with front graphical display and such, but also a built-in DSP. It is not a fancy subsystem but allows you to dial in crossovers and such which is very handy in live sound. At may company (Madrona Digital) we use a ton of Crown amps not for hifi applications but for music distribution in the home. The built-in DSPs come in handy for limiting the frequency range, max output, etc..
Unlike home units, the XLS 1502 has a built-in fan with tons of...
Review and Measurements of Geshelli ENOG2 Pro DAC
This is a review and detailed measurements of Geshelli Labs ENOG2 Pro DAC. It is on kind loan from the company. It retails for USD $199 but right now they are on sale for $180 including free shipping to US and Canada.
The ENOG2 Pro DAC comes in different colors and semi-transparent case. I have the black:
The clear sides allows the myriad of colorful LEDs to shine through. If you are a fan of this kind of bling, you are in luck. If not, you may want to put a towel on it when operating.
The ENOG2 Pro distinguishes itself from other budget DACs by leaving out USB input and instead adding balanced output. As you see in the above picture the only inputs are TOSLINK optical and Coax S/PDIF. If the ENOG2 Pro performs and you don't need USB, it would be the cheapest way to get a balanced output DAC.
Back to functionality, the switch to the left of the inputs is dual function. Just pressing it momentarily will toggle from one input to the other. If...
The ENOG2 Pro DAC comes in different colors and semi-transparent case. I have the black:
The clear sides allows the myriad of colorful LEDs to shine through. If you are a fan of this kind of bling, you are in luck. If not, you may want to put a towel on it when operating.
The ENOG2 Pro distinguishes itself from other budget DACs by leaving out USB input and instead adding balanced output. As you see in the above picture the only inputs are TOSLINK optical and Coax S/PDIF. If the ENOG2 Pro performs and you don't need USB, it would be the cheapest way to get a balanced output DAC.
Back to functionality, the switch to the left of the inputs is dual function. Just pressing it momentarily will toggle from one input to the other. If...
Review and Measurements of IRS2092 IRAUD350 Class D Amplifier
This is a review and detailed measurement of a very common power amplifier platform based on International Rectifier/Infineon's IRS2092 class D amplifier IC. The unit was kindly sent by a member to me for testing. Here is what it looks like:
The products seem to be based a reference design by International Rectifier although I can't find an exact match there. You can get everything from single amplifier board fully populated for USD $40 to the fully finished version I have including volume control for USD $298 from China. Just google for IRS2092 and IRAUD350 and you will get countless hits. Some come with volume control and others not.
Power specifications are all over the map. I think I saw one advertised to produce some 700 watts! Manufacturer specs are vague saying since the IC supports +- 100 volt, the can be used to create very high power amplifiers.
Due to use of linear power supply, the loaned amplifier is quite long...
The products seem to be based a reference design by International Rectifier although I can't find an exact match there. You can get everything from single amplifier board fully populated for USD $40 to the fully finished version I have including volume control for USD $298 from China. Just google for IRS2092 and IRAUD350 and you will get countless hits. Some come with volume control and others not.
Power specifications are all over the map. I think I saw one advertised to produce some 700 watts! Manufacturer specs are vague saying since the IC supports +- 100 volt, the can be used to create very high power amplifiers.
Due to use of linear power supply, the loaned amplifier is quite long...
Review and Measurements of LOXJIE d20 DAC and Headphone Amp
This is a review and detailed measurements of the LOXJIE d20 DAC and headphone amplifier. It is on kind loan from the company. If you have not heard of LOXJIE, it is a spin off from SMSL with colorful designs. The d20 is their first dac and retails for USD $270 including prime shipping. It uses the currently top of the line AK4497 DAC chip from AKM. So in theory it should have excellent performance.
The d20 comes in either blue or red colors. I have the red:
Somewhat unusual for these DACs, it includes an AC mains power supply so there is no external dongle. As you can see from the front panel it has a 1/4 inch headphone jack and the signature, tiny display from SMSL. While I am appreciative of the inclusion of the display, the size is just too small from aesthetic point of view let alone usability. I see the economy of using a small display and reusing it in many designs but wish that SMSL/LOXJIE would go to the next size...
The d20 comes in either blue or red colors. I have the red:
Somewhat unusual for these DACs, it includes an AC mains power supply so there is no external dongle. As you can see from the front panel it has a 1/4 inch headphone jack and the signature, tiny display from SMSL. While I am appreciative of the inclusion of the display, the size is just too small from aesthetic point of view let alone usability. I see the economy of using a small display and reusing it in many designs but wish that SMSL/LOXJIE would go to the next size...