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This is a Review of Audioquest high performance USB cables for digital audio application. http://www.audioquest.com/digital-interconnects/ .
It might come as a surprise to some people who know Audioquest (AQ) as a maker of a popular DragonFly DAC, but AQ was formed 35 years ago by Bill E. Low, and under his direction throughout all these years they have been designing and manufacturing high performance audio and video cables. I actually think it’s very impressive to stay in business for such a long time making a niche product which apparently still in demand and continuous to be a subject of heated on-line discussions. But no matter what and where you read about pros and cons of higher quality cables, in my opinion the controversy often comes from a fact that we hear things differently, we use different headphones and audio sources, and our hearing level changes as we age.
When it comes to wires carrying analog signal, I consider myself to be a “cable believer”. A cable/wire is nothing but a conductor, carrying a signal from a source to a destination. The property of the conductive material will contribute to some level of signal degradation. Some people mistake premium quality cables as “enhancers” of the sound, when in reality you’re just comparing it to a regular copper wire that causes more degradation and as a result makes premium cable to sound enhanced. Thus, I would rather call a premium conductor material cable a “restorer” rather than an “enhancer”. There is no magic about it, and everybody is going to hear a different degree of improvement, while some might not even be able to hear any difference at all. As I said, we all hear things differently and entitled to our own opinion, especially when it’s based on your own experience rather than reading someone else’s opinion who might have a different listening threshold.
For analog signal this makes sense, at least to my ears. But how about a digital signal sent from your laptop/PC to external DAC which decodes this digital signal to analog in order to drive your headphones? We all know, digital signal is just 1s and 0s, a voltage range corresponding to high level and low level. This might come as a surprise to some as well, but digital signal is just a sequence of analog square pulses timed at a specific rate. Thus a theory of “conductive wire” still applies to digital signal, except now we have to worry about jitter. I’m not going to turn this review into a science whitepaper, and instead would encourage those who are interested to read more details about jitter in digital audio stream by visiting these links: http://www.positive-feedback.com/Issue43/jitter.htm and http://www.madronadigital.com/Library/DigitalAudioJitter.html. In a very simple explanation, audio data transfer includes both the data and the timing info. Degradation of signal due to a lower quality cable will cause skew in the analog square edges of “digital” pulse which results in timing inaccuracy that will cause jitter and consequent errors in D/A conversion of the signal.
Though I compressed pages of EE explanation into an oversimplified summary sentence above, it is still a mouthful with a few dozen of words. So I’m going to set all this info aside, and use the only tool I trust and have handy with me – my ears!!! If I get ambitious one of these days, maybe I will set up a measurement experiment looking at the shape of the digital pulses coming right out of my laptop and compare it to measurements after the cable, but until then – my ears will do just fine! After all, we only care about listening end results.
In the past I have been approached by a few other companies asking me to review their cables, and when I saw their pricing of up to $1k – I had to turn it down because I’m not that kind of a cable believer. When AQ asked me if I’m interested to take a “listen” to a few of their usb cables with a price range of $25-$65, I found it to be more reasonable and down to earth. Considering I don’t have any fancy desktop DACs and most of my portable equipment has micro-usb cables, I decided to take Pearl (http://www.audioquest.com/micro-usb-digital-audio/pearl, $25), Forrest (http://www.audioquest.com/micro-usb-digital-audio/forest, $35), and Cinnamon (http://www.audioquest.com/micro-usb-digital-audio/cinnamon, $65) usb to micro-usb cables for a spin!
Each cable arrived in a nicely packaged box with a colorful picture of the cable, description of the material, and general description of benefits with “low jitter and distortion which ensures clarity, warmth, max dynamics, and wide open soundstage” on each box. Each cable was 0.75m (2’5”) long and had a distinct color associated with a name.
Pearl cable had a black rubbery outer insulation (PVC material) with white stripes, I guess corresponding to “pearl”. The cable was thick enough, but still with a good degree of flexibility. Connectors on each side were gold plated and with a high quality black housing mold (plastic body with a rubbery strain relief). I'm very particular about micro-usb connectors since a lot of them engage loosely due to a poor construction of small latching hooks. This one interconnected security with all of my devices. Also, this particular Pearl cable was build using solid long-grain copper conductor wire, versus multiple hair-thin copper wires.
Forest had a corresponding black rubbery insulation (PVC material) with a green stripe pattern. This cable was of the same length as others, the same type of plastic quality connector housing with a molded rubber strain relief, and gold plated connector. In general, it looked and felt very similar to Pearl, but its solid conductor wire had a composition with 0.5% silver. In comparison to copper, silver has a higher conductivity and lower resistivity property which purifies the conductive material. In digital audio application, higher-frequency signal travels on the surface of the conductor, thus AQ silver-plated the outer "layer" of their cable where % of silver is relative to the copper conductor.
Cinnamon “eye candy” was definitely a step up from the other two cables. Though with a same 0.75m length, it had a more premium exterior design and interior material. Instead of PVC insulation, now you have a braided pattern with interweaved black and red synthetic strings. It was actually nice to the touch and still maintained a good level of flexibility. Connectors on both sides are also gold plated and have a rubbery strain relief mold, but the main part of the connector housing was in red. Actually, a combination of red and gold makes it a cool accessory for any Iron Man fan! Inside, Cinnamon cable has 1.25% of silver relative to the copper conductor. Obviously, higher percentage of silver suggests a thicker silver plated outer layer for a more "purified" digital audio path.
For sure, these are nice looking and durable cables, but the purpose of this review is to see how they perform in audio application. As a mentioned before, I don’t have any dedicated desktop DACs/amps, so I was using Astell & Kern AK120ii and Cayin N6 DAPs with my ATH-MSR7 high-res full size headphones and various FLAC files playing in Foobar2k. If I could, I would have used DSD files, but I always run into issues setting up codec on my laptop. In my opinion, testing with higher res format will have a better comparison effect because errors in data stream could translate into a similar effect as you hear with down-sampling, although not to the same extreme since down-sampling is consistent versus effect of jitter being more random. For the reference, in addition to 3 AQ cables, I also picked a random generic usb to micro-usb cable that came with either a phone or another DAP.
Keep in mind, this is a relative comparison describing how I hear it playing the same set of the songs with the same set of headphones and DAP with the only difference of switching between 4 cables.
- Regular cable (baseline): warm organic sound with above average soundstage width and a more intimate depth.
- Pearl (long grain copper): slightly brighter and a bit more detailed sound, staging is a little bit wider while soundstage depth has the same intimacy.
- Forest (0.5% silver): same brightness is pearl, same retrieval of details as pearl, and same soundstage width/depth.
- Cinnamon (1.25% silver): same brightness as pearl/forest, a more noticeable improvement in retrieval of details (I’m hearing more finesse in accentuated nuances from every direction), and soundstage width and depth has a more noticeable improvement.
The improvement in sound was more noticeable with N6 (a brighter source) rather than AK120ii (a warmer source). I had many listening sessions doing comparison over the period of almost 2 weeks, going through comparison across 4 cables, and found the results to be consistent. YMMV, but without a single ounce of doubt in my mind I do hear a difference between a generic usb cable and AQ cables. When it comes to differences between AQ cables, Pearl and Forest in my setup sounds nearly identical. Step up to Cinnamon, and now you hear more refinement where a generic cable in comparison sounds just veiled. I know, it is crazy that I'm talking about retrieval of details, veiled, and soundstage improvement in a content of digital audio usb cable, but despite what you read on-line from others who hear or don't hear the difference, or who believe or don't believe the changes - I'm hearing it with my own ears!
With Cinnamon cable and Cayin N6 using my MSR7, I got chills while playing Michael Jackson "Beat It" mastered version (24bit/96kHz FLAC @3.184Mbps bitrate) because I heard some tiny details that were completely lost while playing it with a regular usb cable which felt like a down-sampled performance. I think it's a very important factor that even with the best set of headphone and DAC/usb-DAP - you also need a high res audio to take the full advantage of this "sound" improvement. Compressed 320kbps mp3 didn't yield the same level of difference. And again, "level" is a relative term. In this one particular case with a particular set of headphones, DAP, and high-res FLAC file - I was very impressed. Not necessary night'n'day impressed, but it was noticeable enough for me to appreciate this cable.
Another interesting discovery, not necessary audio related, but due to a hefty gauge of the wires and proper isolation I was able to confirm charging speed of AQ cables to be close to 2A. In my test using Charger Doctor usb monitor I was getting a current reading of 1.78-1.8A, and I'm aware that Charger Doctor by itself sinks about 100-150mA which offsets the actual reading. Thus, another advantage of these AQ cables is being able to charge your smartphone or DAP at full speed.
Conclusion.
I'm not a snake oil salesman. And even if I would hear a similar level of improvement using other $1k cables, I would never dare to write about those cables because it just makes no sense to pay that much money for a marginal improvement. Yes, cables are in a category of diminishing returns. But for those who invested thousands of dollars into their desktop audio setup or who use their TOTL DAP as USB DAC to play high res files from laptop and want to squeeze every ounce of performance - perhaps looking into $25-$35 cable is not a bad idea. Moving up to $65 is pricey for sure, but it's more than just higher % of silver since you are also getting a more premium design.
I really don't want to open a can of worms with this review. I'm not associated with AQ or have any benefits if you buy or don't buy their product. I'm just a reviewer who was given an opportunity to take a listen to their cables to find out myself if they make any difference in my audio setup. That's exactly what I did, and can confirm that indeed - I do hear a difference! Aside from a technical explanation, I trust my ears and believe what I'm hearing, rather than what others are saying I should or shouldn't hear with replacement usb cables. With all that, I can't tell you if this cable is a must have or not, YMMV because there are too many variables in this equation to get to the maximum level of sound improvement. But if you decide to give it a try, I think it's more reasonable than other stuff that costs at least 10-20 times more.
It might come as a surprise to some people who know Audioquest (AQ) as a maker of a popular DragonFly DAC, but AQ was formed 35 years ago by Bill E. Low, and under his direction throughout all these years they have been designing and manufacturing high performance audio and video cables. I actually think it’s very impressive to stay in business for such a long time making a niche product which apparently still in demand and continuous to be a subject of heated on-line discussions. But no matter what and where you read about pros and cons of higher quality cables, in my opinion the controversy often comes from a fact that we hear things differently, we use different headphones and audio sources, and our hearing level changes as we age.
When it comes to wires carrying analog signal, I consider myself to be a “cable believer”. A cable/wire is nothing but a conductor, carrying a signal from a source to a destination. The property of the conductive material will contribute to some level of signal degradation. Some people mistake premium quality cables as “enhancers” of the sound, when in reality you’re just comparing it to a regular copper wire that causes more degradation and as a result makes premium cable to sound enhanced. Thus, I would rather call a premium conductor material cable a “restorer” rather than an “enhancer”. There is no magic about it, and everybody is going to hear a different degree of improvement, while some might not even be able to hear any difference at all. As I said, we all hear things differently and entitled to our own opinion, especially when it’s based on your own experience rather than reading someone else’s opinion who might have a different listening threshold.
For analog signal this makes sense, at least to my ears. But how about a digital signal sent from your laptop/PC to external DAC which decodes this digital signal to analog in order to drive your headphones? We all know, digital signal is just 1s and 0s, a voltage range corresponding to high level and low level. This might come as a surprise to some as well, but digital signal is just a sequence of analog square pulses timed at a specific rate. Thus a theory of “conductive wire” still applies to digital signal, except now we have to worry about jitter. I’m not going to turn this review into a science whitepaper, and instead would encourage those who are interested to read more details about jitter in digital audio stream by visiting these links: http://www.positive-feedback.com/Issue43/jitter.htm and http://www.madronadigital.com/Library/DigitalAudioJitter.html. In a very simple explanation, audio data transfer includes both the data and the timing info. Degradation of signal due to a lower quality cable will cause skew in the analog square edges of “digital” pulse which results in timing inaccuracy that will cause jitter and consequent errors in D/A conversion of the signal.
Though I compressed pages of EE explanation into an oversimplified summary sentence above, it is still a mouthful with a few dozen of words. So I’m going to set all this info aside, and use the only tool I trust and have handy with me – my ears!!! If I get ambitious one of these days, maybe I will set up a measurement experiment looking at the shape of the digital pulses coming right out of my laptop and compare it to measurements after the cable, but until then – my ears will do just fine! After all, we only care about listening end results.
In the past I have been approached by a few other companies asking me to review their cables, and when I saw their pricing of up to $1k – I had to turn it down because I’m not that kind of a cable believer. When AQ asked me if I’m interested to take a “listen” to a few of their usb cables with a price range of $25-$65, I found it to be more reasonable and down to earth. Considering I don’t have any fancy desktop DACs and most of my portable equipment has micro-usb cables, I decided to take Pearl (http://www.audioquest.com/micro-usb-digital-audio/pearl, $25), Forrest (http://www.audioquest.com/micro-usb-digital-audio/forest, $35), and Cinnamon (http://www.audioquest.com/micro-usb-digital-audio/cinnamon, $65) usb to micro-usb cables for a spin!
Each cable arrived in a nicely packaged box with a colorful picture of the cable, description of the material, and general description of benefits with “low jitter and distortion which ensures clarity, warmth, max dynamics, and wide open soundstage” on each box. Each cable was 0.75m (2’5”) long and had a distinct color associated with a name.
Pearl cable had a black rubbery outer insulation (PVC material) with white stripes, I guess corresponding to “pearl”. The cable was thick enough, but still with a good degree of flexibility. Connectors on each side were gold plated and with a high quality black housing mold (plastic body with a rubbery strain relief). I'm very particular about micro-usb connectors since a lot of them engage loosely due to a poor construction of small latching hooks. This one interconnected security with all of my devices. Also, this particular Pearl cable was build using solid long-grain copper conductor wire, versus multiple hair-thin copper wires.
Forest had a corresponding black rubbery insulation (PVC material) with a green stripe pattern. This cable was of the same length as others, the same type of plastic quality connector housing with a molded rubber strain relief, and gold plated connector. In general, it looked and felt very similar to Pearl, but its solid conductor wire had a composition with 0.5% silver. In comparison to copper, silver has a higher conductivity and lower resistivity property which purifies the conductive material. In digital audio application, higher-frequency signal travels on the surface of the conductor, thus AQ silver-plated the outer "layer" of their cable where % of silver is relative to the copper conductor.
Cinnamon “eye candy” was definitely a step up from the other two cables. Though with a same 0.75m length, it had a more premium exterior design and interior material. Instead of PVC insulation, now you have a braided pattern with interweaved black and red synthetic strings. It was actually nice to the touch and still maintained a good level of flexibility. Connectors on both sides are also gold plated and have a rubbery strain relief mold, but the main part of the connector housing was in red. Actually, a combination of red and gold makes it a cool accessory for any Iron Man fan! Inside, Cinnamon cable has 1.25% of silver relative to the copper conductor. Obviously, higher percentage of silver suggests a thicker silver plated outer layer for a more "purified" digital audio path.
For sure, these are nice looking and durable cables, but the purpose of this review is to see how they perform in audio application. As a mentioned before, I don’t have any dedicated desktop DACs/amps, so I was using Astell & Kern AK120ii and Cayin N6 DAPs with my ATH-MSR7 high-res full size headphones and various FLAC files playing in Foobar2k. If I could, I would have used DSD files, but I always run into issues setting up codec on my laptop. In my opinion, testing with higher res format will have a better comparison effect because errors in data stream could translate into a similar effect as you hear with down-sampling, although not to the same extreme since down-sampling is consistent versus effect of jitter being more random. For the reference, in addition to 3 AQ cables, I also picked a random generic usb to micro-usb cable that came with either a phone or another DAP.
Keep in mind, this is a relative comparison describing how I hear it playing the same set of the songs with the same set of headphones and DAP with the only difference of switching between 4 cables.
- Regular cable (baseline): warm organic sound with above average soundstage width and a more intimate depth.
- Pearl (long grain copper): slightly brighter and a bit more detailed sound, staging is a little bit wider while soundstage depth has the same intimacy.
- Forest (0.5% silver): same brightness is pearl, same retrieval of details as pearl, and same soundstage width/depth.
- Cinnamon (1.25% silver): same brightness as pearl/forest, a more noticeable improvement in retrieval of details (I’m hearing more finesse in accentuated nuances from every direction), and soundstage width and depth has a more noticeable improvement.
The improvement in sound was more noticeable with N6 (a brighter source) rather than AK120ii (a warmer source). I had many listening sessions doing comparison over the period of almost 2 weeks, going through comparison across 4 cables, and found the results to be consistent. YMMV, but without a single ounce of doubt in my mind I do hear a difference between a generic usb cable and AQ cables. When it comes to differences between AQ cables, Pearl and Forest in my setup sounds nearly identical. Step up to Cinnamon, and now you hear more refinement where a generic cable in comparison sounds just veiled. I know, it is crazy that I'm talking about retrieval of details, veiled, and soundstage improvement in a content of digital audio usb cable, but despite what you read on-line from others who hear or don't hear the difference, or who believe or don't believe the changes - I'm hearing it with my own ears!
With Cinnamon cable and Cayin N6 using my MSR7, I got chills while playing Michael Jackson "Beat It" mastered version (24bit/96kHz FLAC @3.184Mbps bitrate) because I heard some tiny details that were completely lost while playing it with a regular usb cable which felt like a down-sampled performance. I think it's a very important factor that even with the best set of headphone and DAC/usb-DAP - you also need a high res audio to take the full advantage of this "sound" improvement. Compressed 320kbps mp3 didn't yield the same level of difference. And again, "level" is a relative term. In this one particular case with a particular set of headphones, DAP, and high-res FLAC file - I was very impressed. Not necessary night'n'day impressed, but it was noticeable enough for me to appreciate this cable.
Another interesting discovery, not necessary audio related, but due to a hefty gauge of the wires and proper isolation I was able to confirm charging speed of AQ cables to be close to 2A. In my test using Charger Doctor usb monitor I was getting a current reading of 1.78-1.8A, and I'm aware that Charger Doctor by itself sinks about 100-150mA which offsets the actual reading. Thus, another advantage of these AQ cables is being able to charge your smartphone or DAP at full speed.
Conclusion.
I'm not a snake oil salesman. And even if I would hear a similar level of improvement using other $1k cables, I would never dare to write about those cables because it just makes no sense to pay that much money for a marginal improvement. Yes, cables are in a category of diminishing returns. But for those who invested thousands of dollars into their desktop audio setup or who use their TOTL DAP as USB DAC to play high res files from laptop and want to squeeze every ounce of performance - perhaps looking into $25-$35 cable is not a bad idea. Moving up to $65 is pricey for sure, but it's more than just higher % of silver since you are also getting a more premium design.
I really don't want to open a can of worms with this review. I'm not associated with AQ or have any benefits if you buy or don't buy their product. I'm just a reviewer who was given an opportunity to take a listen to their cables to find out myself if they make any difference in my audio setup. That's exactly what I did, and can confirm that indeed - I do hear a difference! Aside from a technical explanation, I trust my ears and believe what I'm hearing, rather than what others are saying I should or shouldn't hear with replacement usb cables. With all that, I can't tell you if this cable is a must have or not, YMMV because there are too many variables in this equation to get to the maximum level of sound improvement. But if you decide to give it a try, I think it's more reasonable than other stuff that costs at least 10-20 times more.