project86
Headphoneus Supremus
- Joined
- Feb 21, 2007
- Posts
- 7,804
- Likes
- 4,377
INTRO
This review is going to be a bit shorter than my others, at least for the time being. The reason is simply a matter of time management. The device being reviewed has so many options, and so many variables that can affect its operation, that it remains an ongoing process. I will update as I get the time.
So what is this thing that it takes so long and is so complicated? I’ll start by saying it’s actually just a DAC with a matching headphone amp. The DAC module has most of the usual features like USB, coaxial, and toslink inputs. It uses the Burr/Brown DIR9001 receiver and does asynchronous sample rate conversion via the Cirrus Logic CS8421. The amp portion features the older but still nice Texas Instruments TPA6120A2, has a rechargeable battery, and features separate headphone jacks: 1/8” for 16-250ohm headphones and a 1/4” for 250-600ohm loads. Everything sounds pretty normal so far right? I neglected to mention that the DAC section also features an AKM AK5381 analog to digital converter. That’s odd. Even stranger is the fact that the headphone amp section contains a Wolfson 8740 chip. Yes, you read that correctly, the DAC chip is in the amp section. The reason for that is because the DAC section is actually not quite a DAC but rather a wireless transmitter. It accepts digital data from its various digital inputs, as well as analog data converted to digital via the AKM chip, and sends an uncompressed digital signal wirelessly to the amp section which is actually a wireless receiver. The receiver then takes that digital signal and performs the digital to analog conversion, and finally amplifies that signal to be output to your headphones. It’s really quite an elegant system.
The seller of this item has listed it on Ebay Portable Wireless Headphone Amplifier & DAC (JHC-A2) - eBay (item 290430050219 end time May-05-10 17:39:38 PDT) as well as Audiogon and a few other places. It doesn’t look like he has sold many from what I can see. I had some questions about the device so I contacted him, and he is a very nice guy. We got to talking and he offered to send me a sample for review. His English is somewhat limited but from what I’ve been able to gather he is the head of a company called JHC and this device is the JHC-A2, hereafter referred to as simply the A2. I’ve has it for about a month now and I still have not been able to test it as much as I’d like.
PACKAGING
The box arrived in good shape. Honestly the design of the box is kind of cheesy looking and reminds me of something that might be found at a flea market. Once opened though the box has a nice Styrofoam insert with cutouts for each specific component. Included in the box (aside from the transmitter and the receiver of course) is bundle of accessories consisting of a wall wart power supply, usb cable, toslink cable, and instruction manual.
DESIGN
The transmitter and the receiver units are each housed in a fairly nice black brushed aluminum enclosure. On the back panel of each is a small antenna similar to what you find on most wireless routers. The antennae are flexible and can be folded down if you don’t like the look of them. The front panel of each unit consists of buttons for each feature; the switches and knobs commonly found on DACs and amps are not to be found here. Volume control is obviously done in the digital domain and it is done rather well; each push of the volume up or down buttons gives a very slight change in sound. If the button is held down, it takes roughly 8 seconds to go from silent to deafeningly loud or vice versa.
The A2 operates on the 2.4 GHz frequency band. It actually has 3 options, each 25 MHz apart from each other, to be used in case of interference. Each unit has a red button on front labeled ID_SEL and when held simultaneously they switch frequencies for you. Power is provided by a set of 4 AA 2700 mAh rechargeable batteries which are charged just by plugging in the receiver to the power supply. One admittedly minor complaint is that there is only one power supply included which normally needs to stay plugged in to the transmitter, so the user must unplug that and switch it to the receiver when it is time to charge.
As you can see in the pictures, the transmitter has LED lights on the front panel indicating which input you have selected, much like many standard DACs have. The transmitter has a red LED labeled No Audio which lights up whenever no signal is present. The receiver has a blue LED labeled Sync which lights when a lock is achieved with the transmitter, again much like a standard DAC. It’s all fairly simple and easy to use.
One interesting aspect is that all info gets converted to 16-bit/48k before being sent wirelessly to the receiver. The toslink and coaxial inputs supposedly accept 24/96 material and the USB input is oddly limited to 16/48. But then it all gets changed to 16/48 anyway through the ASRC process. I speculate that this is due to a bandwidth limitation on the wireless module, but I could be wrong.
BUILD QUALITY
This device is quite a contrast. In many ways it looks and feels like a well built mid to high end product. But there are a few areas in which is seems a bit amateurish, like a DIY kit that has been lovingly built for performance rather than fit and finish. On the plus side, the enclosure is quite nice. It is a fingerprint magnet but that can’t be helped when dealing with an almost mirror finish. It has a nice internal channel on each side into which the PCB can slide rather than being screwed in like some products. This makes the entire assembly fit well without wiggling around inside. The battery container is only connected by a wire, but it is held snug by a size matched piece of foam that prevents it from touching the PCB. It works much better than some amps I’ve seen which have batteries rattling around in the case.
On the other hand, some things don’t quite feel as solid. The antennae both feel loose on the back panel in a way which does not inspire confidence. That is fairly common with most wireless router I’ve dealt with so I’m not too worried about that. The front and rear panels take a bit of care to get lined up properly when trying to put the units back together, and the screw holes seem like they could easily become stripped if you are not careful. This is not a unit you want to take apart repeatedly. Thankfully you shouldn’t have to, as the batteries should last quite a while. When they stop holding a charge you can replace them with off the shelf rechargeables which is a nice touch. The seller advised me he had created an earlier version, dubbed the JHC A1, which used some higher end parts in the amp section as well as a lithium ion battery, but the battery did not last very long so he changed that around.
Another aspect that isn’t really build quality per se, but does fall into this category, is the choice of text and fonts used on the units. Everything is well printed onto the cases with no fading or chipping, but it doesn’t look very attractive. Much more care could have been taken in choosing an aesthetically pleasing design rather than the clunky font that was used. That would go a long way towards making the product look less like a DIY design and more like a premium product.
REVIEW EQUIPMENT
Since there are so many potential configurations with this unit, I tried to keep things as simple as possible. I fed it digital signals from both the coaxial and the optical outputs of a Lexicon RT-20 universal player, and could not tell the difference between them. I also used that same Lexicon to feed the A2 an analog stereo signal. I have not yet had a chance to use the USB input other than to verify that it does work. I hope to do more of that soon.
Listening was done with some of my favorite headphones including the Beyerdynamic DT990 (600 ohm version) and DT880 (250 ohm version), Sennheiser HD600, Ultimate Ears SuperFi 3, LiveWires Trips, and Equation Audio RP21.
Music used was a wide variety of genres with varying degrees of sound quality ranging from excellent to fairly bad. Here is a partial list:
Dashboard Confessional – Dusk and Summer
A Fine Frenzy – Bomb in a Birdcage
Abigail Williams – Legend
Hiromi – Brain
Kraftwerk – The Catalogue
Steve Miller Band – The Joker
Sufjan Stevens – Seven Swans
Underoath – Lost in the Sound of Seperation
XRCD Classical Sampler
Ernie Watts – Unity XRCD
Emancipator – Safe in the Steep Cliffs
Girl Talk - Tsuyoshi Yamamoto Trio
I also watched some stuff on DVD that has pretty strong audio including:
Into The Wild
The Pyongyang Concert - New York Philharmonic & Lorin Maazel
Flight of the Conchords Season 1
LISTENING
The first thing I have to mention is that there is way more to this device than the usual DAC or amp. Since the signal is being converted and sent wirelessly, you are not only dealing with the quality of the DAC implementation and the headphone amp itself, but also the ability of the unit to maintain an interference free signal. This is harder than it sounds when you consider that many things in the average house could potentially cause problems. The usual suspects for wireless interference include microwaves, televisions, cordless phones, and plain old physical barriers like walls. Add to that list the practically ubiquitous Wi-Fi that most houses have, and in my case an extra hazard in the form of a wireless baby monitor, and you can imagine what a minefield this signal is wading through.
I’m happy to say that for the most part, the JHC-A2 performs very well. The receiver unit takes a few seconds to lock on to the signal, at which point an indicator light turns on to advice that things are moving along. One part I don’t like is the default volume setting: it is very loud when the signal locks and the music first kicks in. Without actually checking, I estimate that it starts out at or near maximum volume. Not only that, but if you turn the receiver off and then back on, it restarts at the higher volume, even if you had turned it down once already. Something to be very careful about especially if using IEMs.
99% of the time I got smooth playback with no interference or problems. There were a handful of times when I got a loud clicking noise which sounded a bit like a FM static mixed with digital distortion on a scratched CD. I’m not sure what prompted this to happen as I was stationary at the time. It only happened a handful of times during my many hours of testing, but I’d much prefer that it didn’t happen at all. Another issue was that I intermittently got a faint high pitched buzz in the right channel. It sounded the worst with my extremely sensitive LiveWires, and was actually quite a distraction on some music. On most other headphones it was not much of an issue. I likened it to the hiss or hum that I have on some of my other amps, and it is much more difficult to notice when music is playing. In fact I almost think it goes away all together when music is playing, but I have to confirm that with more hours of testing.
Speaking of hours, I should address the battery life. On the Ebay listing, the seller advertises 6 hours maximum battery life. But on the side of the box it says 3.5 hours. My real world usage averaged somewhere in between those two figures depending on headphones used and volume level. That doesn’t sound like much until you consider that this unit is not only acting as an amplifier but also a receiver and DAC all in one. I don’t know of another product that does those things on battery power so I can’t say this unit is substandard in that regard. I can only mention that the battery life ended up being less of an issue than I originally anticipated. I could easily watch an entire film, even a really long one, and still have juice to spare. I ended up just charging it a few nights a week, and that worked well for me.
Here are my impressions of sound quality using various headphones:
Equation Audio RP-21
These cans are fairly easy to drive, and they sound about as good as I’ve ever heard them on the JCH-A2. Their strong point is bass and there is plenty to be heard here, without any extra bloat or sloppiness. The soundstage is, as usual, somewhat limited, likely a consequence of their closed construction. But everything else is top notch to the point where you almost wonder how it could possibly be improved. That is, of course, only until you listen to a truly high end headphone. Still, there is a lot to like here and the JHC-A2 is a very good match. The only complaint is the maximum volume is somewhat limited. Not that I would often listen at such high levels, but it could be a problem for a small amount of music.
LiveWires Trips
As I mentioned before, these are highly sensitive. More than 50% of the time I get the high pitched buzz in the left channel. I have so far been unable to pinpoint what is causing this issue. I suppose I could unplug all my wireless devices and see if that solves it, but that has not been possible so far.
Other than that the Trips sound pretty good with the A2. There is a nice warm sound signature with plenty of detail. Bass is good but seems just a tad rolled off compared to how it sounds when used with higher end equipment. Highs suffer similarly, by losing just a touch of that sparkle that makes these truly great IEMs. In the case of the highs, it might be a blessing in disguise because the Trips can be ruthlessly revealing of any sibilance or harshness. Of course, it is hard to determine if this is caused by the DAC or the amp section. There is no problem with maximum volume here though; it gets as loud as you could possibly want.
Sennheiser HD600
The classic HD600 has developed a bit of a reputation as a difficult to drive headphone. The JHC-A2 is quite capable of driving them very well, although the result is not quite among the best I’ve heard. Still, the performance is pretty solid, with very nice imaging and great dynamics. I was especially impressed with the micro detail that I heard on some more delicate jazz tracks. The HD600 seems under rated when it comes to detail recovery, and this DAC/amp helps show that fact.
Compared to my Vivid Technologies V1 portable amp, the JHC-A2 sounds somewhat laid back and mellow. It’s very good, and in fact might be preferable depending on your mood and the program material, but it is not as exciting. Female vocals can sound like they are farther back in the mix, and male vocals gain an added heft.
Beyerdynamic DT-990 600 ohm
This is one headphone that isn’t a great match for the A2. I like the presentation of the high quite well, in fact the slight rolled off nature sounds better here than with many other amps. But the bass doesn’t sound quite right. It seems to have a lack of authority which changes the usually lovable nature of these cans. It almost feels like the 990s are doing an impersonation of the 880s, and it is a bad impersonation. What sounds clear and neutral on the 880s seems limp and thin on the 990s.
In defense of the A2, the 600 ohm DT990s is kind of a bear to drive. Many an amp has tried and failed with these things so I don’t think it is a dealbreaker.
Beyerdynamic DT880 250 ohm
Now that’s more like it. The A2 controls these things very well, with a lush and silky midrange that is not always present with lesser amps. The thing that jumps out at me is how quick this combo sounds; transients on tricky material like Brain from Hiromi sounded spot on, and even simple things like the string across a cello sounds vivid and lifelike.
Without being able to separate the DAC from the amp section, I’m going out on a limb to say the DAC is pretty revealing. It’s also fairly even handed and neutral, excelling at all types of music. The amp section is basically more of the same, and aside from feeling like it sometimes runs out of steam a bit early, it really satisfies all the requirements that a lower-mid level amp should. I don’t mean that as an insult: I’ve heard $500 amps that don’t perform as well. I’ll be doing a lot more listening with these because they sound very nice with this amp.
Ultimate Ears Super Fi 3
These are classics in my book. They remind me of a decent bookshelf monitor, in that there is not a ton of bass but what is there is nice, and for me they give an interesting perspective on the music that not many IEMs or headphones can give. I think it’s because they are somewhat less accurate than most of my IEMs, and they force me to focus on the performance to enjoy it rather than just letting me sit back and relax. That sounds kind of silly but that’s how I feel. Obviously they are not the best at many things but are a good tool none the less.
The A2 is simply brilliant with the SF3. I don’t think there is a single area that could be improved. Switching to the Matrix M-Stage or the DarkVoice 337SE doesn’t seem to do anything to make them sound better. Maybe they are just maxed out, and it is caused by the limitation of the SF3 rather than the prowess of the JHC. Whatever the case I’m enjoying the “synergy” here.
CONCLUSION
This is far from a final conclusion, as I will be spending time with this product and adding to this review as time goes by. But it certainly is an interesting item. I think the most fun I’ve had with it is from watching movies. The slightly laid back presentation goes very well with most movies and soundtrack material, and the ability to do without messy wires is a joy.
The JHC-A2 sounded better than most of the headphone jacks on my gear. I have a few higher end items like vintage McIntosh and pricey Marantz that edge out the A2, but not by much. Using the analog input on the A2 only slightly degrades the sound quality, shrinking sound stage and making things a bit too dark compared to the digital inputs. This must be due to the extra ADC process that is introduced by doing this step. Still, I appreciate the fact that the analog inputs are there, and I often found myself utilizing 3 of the 4 inputs during testing. USB is still something that I need to spend more time with.
The novelty of this product is the fact that it does something I’ve never seen done before. Once you get over that you find yourself with a very nice little DAC and matching amp. If I had paid the $250 for a DAC and amp (either a combo unit or separate pieces), and achieved this sound, I would be pleased with the value. The fact that it all happens wirelessly makes it even better.
More to come when I get time.
PS I didn't know where to put this as it is sort of portable, and also considered a source, and could even be computer audiophile related..... so I just chose here.
This review is going to be a bit shorter than my others, at least for the time being. The reason is simply a matter of time management. The device being reviewed has so many options, and so many variables that can affect its operation, that it remains an ongoing process. I will update as I get the time.
So what is this thing that it takes so long and is so complicated? I’ll start by saying it’s actually just a DAC with a matching headphone amp. The DAC module has most of the usual features like USB, coaxial, and toslink inputs. It uses the Burr/Brown DIR9001 receiver and does asynchronous sample rate conversion via the Cirrus Logic CS8421. The amp portion features the older but still nice Texas Instruments TPA6120A2, has a rechargeable battery, and features separate headphone jacks: 1/8” for 16-250ohm headphones and a 1/4” for 250-600ohm loads. Everything sounds pretty normal so far right? I neglected to mention that the DAC section also features an AKM AK5381 analog to digital converter. That’s odd. Even stranger is the fact that the headphone amp section contains a Wolfson 8740 chip. Yes, you read that correctly, the DAC chip is in the amp section. The reason for that is because the DAC section is actually not quite a DAC but rather a wireless transmitter. It accepts digital data from its various digital inputs, as well as analog data converted to digital via the AKM chip, and sends an uncompressed digital signal wirelessly to the amp section which is actually a wireless receiver. The receiver then takes that digital signal and performs the digital to analog conversion, and finally amplifies that signal to be output to your headphones. It’s really quite an elegant system.
The seller of this item has listed it on Ebay Portable Wireless Headphone Amplifier & DAC (JHC-A2) - eBay (item 290430050219 end time May-05-10 17:39:38 PDT) as well as Audiogon and a few other places. It doesn’t look like he has sold many from what I can see. I had some questions about the device so I contacted him, and he is a very nice guy. We got to talking and he offered to send me a sample for review. His English is somewhat limited but from what I’ve been able to gather he is the head of a company called JHC and this device is the JHC-A2, hereafter referred to as simply the A2. I’ve has it for about a month now and I still have not been able to test it as much as I’d like.
PACKAGING
The box arrived in good shape. Honestly the design of the box is kind of cheesy looking and reminds me of something that might be found at a flea market. Once opened though the box has a nice Styrofoam insert with cutouts for each specific component. Included in the box (aside from the transmitter and the receiver of course) is bundle of accessories consisting of a wall wart power supply, usb cable, toslink cable, and instruction manual.
DESIGN
The transmitter and the receiver units are each housed in a fairly nice black brushed aluminum enclosure. On the back panel of each is a small antenna similar to what you find on most wireless routers. The antennae are flexible and can be folded down if you don’t like the look of them. The front panel of each unit consists of buttons for each feature; the switches and knobs commonly found on DACs and amps are not to be found here. Volume control is obviously done in the digital domain and it is done rather well; each push of the volume up or down buttons gives a very slight change in sound. If the button is held down, it takes roughly 8 seconds to go from silent to deafeningly loud or vice versa.
The A2 operates on the 2.4 GHz frequency band. It actually has 3 options, each 25 MHz apart from each other, to be used in case of interference. Each unit has a red button on front labeled ID_SEL and when held simultaneously they switch frequencies for you. Power is provided by a set of 4 AA 2700 mAh rechargeable batteries which are charged just by plugging in the receiver to the power supply. One admittedly minor complaint is that there is only one power supply included which normally needs to stay plugged in to the transmitter, so the user must unplug that and switch it to the receiver when it is time to charge.
As you can see in the pictures, the transmitter has LED lights on the front panel indicating which input you have selected, much like many standard DACs have. The transmitter has a red LED labeled No Audio which lights up whenever no signal is present. The receiver has a blue LED labeled Sync which lights when a lock is achieved with the transmitter, again much like a standard DAC. It’s all fairly simple and easy to use.
One interesting aspect is that all info gets converted to 16-bit/48k before being sent wirelessly to the receiver. The toslink and coaxial inputs supposedly accept 24/96 material and the USB input is oddly limited to 16/48. But then it all gets changed to 16/48 anyway through the ASRC process. I speculate that this is due to a bandwidth limitation on the wireless module, but I could be wrong.
BUILD QUALITY
This device is quite a contrast. In many ways it looks and feels like a well built mid to high end product. But there are a few areas in which is seems a bit amateurish, like a DIY kit that has been lovingly built for performance rather than fit and finish. On the plus side, the enclosure is quite nice. It is a fingerprint magnet but that can’t be helped when dealing with an almost mirror finish. It has a nice internal channel on each side into which the PCB can slide rather than being screwed in like some products. This makes the entire assembly fit well without wiggling around inside. The battery container is only connected by a wire, but it is held snug by a size matched piece of foam that prevents it from touching the PCB. It works much better than some amps I’ve seen which have batteries rattling around in the case.
On the other hand, some things don’t quite feel as solid. The antennae both feel loose on the back panel in a way which does not inspire confidence. That is fairly common with most wireless router I’ve dealt with so I’m not too worried about that. The front and rear panels take a bit of care to get lined up properly when trying to put the units back together, and the screw holes seem like they could easily become stripped if you are not careful. This is not a unit you want to take apart repeatedly. Thankfully you shouldn’t have to, as the batteries should last quite a while. When they stop holding a charge you can replace them with off the shelf rechargeables which is a nice touch. The seller advised me he had created an earlier version, dubbed the JHC A1, which used some higher end parts in the amp section as well as a lithium ion battery, but the battery did not last very long so he changed that around.
Another aspect that isn’t really build quality per se, but does fall into this category, is the choice of text and fonts used on the units. Everything is well printed onto the cases with no fading or chipping, but it doesn’t look very attractive. Much more care could have been taken in choosing an aesthetically pleasing design rather than the clunky font that was used. That would go a long way towards making the product look less like a DIY design and more like a premium product.
REVIEW EQUIPMENT
Since there are so many potential configurations with this unit, I tried to keep things as simple as possible. I fed it digital signals from both the coaxial and the optical outputs of a Lexicon RT-20 universal player, and could not tell the difference between them. I also used that same Lexicon to feed the A2 an analog stereo signal. I have not yet had a chance to use the USB input other than to verify that it does work. I hope to do more of that soon.
Listening was done with some of my favorite headphones including the Beyerdynamic DT990 (600 ohm version) and DT880 (250 ohm version), Sennheiser HD600, Ultimate Ears SuperFi 3, LiveWires Trips, and Equation Audio RP21.
Music used was a wide variety of genres with varying degrees of sound quality ranging from excellent to fairly bad. Here is a partial list:
Dashboard Confessional – Dusk and Summer
A Fine Frenzy – Bomb in a Birdcage
Abigail Williams – Legend
Hiromi – Brain
Kraftwerk – The Catalogue
Steve Miller Band – The Joker
Sufjan Stevens – Seven Swans
Underoath – Lost in the Sound of Seperation
XRCD Classical Sampler
Ernie Watts – Unity XRCD
Emancipator – Safe in the Steep Cliffs
Girl Talk - Tsuyoshi Yamamoto Trio
I also watched some stuff on DVD that has pretty strong audio including:
Into The Wild
The Pyongyang Concert - New York Philharmonic & Lorin Maazel
Flight of the Conchords Season 1
LISTENING
The first thing I have to mention is that there is way more to this device than the usual DAC or amp. Since the signal is being converted and sent wirelessly, you are not only dealing with the quality of the DAC implementation and the headphone amp itself, but also the ability of the unit to maintain an interference free signal. This is harder than it sounds when you consider that many things in the average house could potentially cause problems. The usual suspects for wireless interference include microwaves, televisions, cordless phones, and plain old physical barriers like walls. Add to that list the practically ubiquitous Wi-Fi that most houses have, and in my case an extra hazard in the form of a wireless baby monitor, and you can imagine what a minefield this signal is wading through.
I’m happy to say that for the most part, the JHC-A2 performs very well. The receiver unit takes a few seconds to lock on to the signal, at which point an indicator light turns on to advice that things are moving along. One part I don’t like is the default volume setting: it is very loud when the signal locks and the music first kicks in. Without actually checking, I estimate that it starts out at or near maximum volume. Not only that, but if you turn the receiver off and then back on, it restarts at the higher volume, even if you had turned it down once already. Something to be very careful about especially if using IEMs.
99% of the time I got smooth playback with no interference or problems. There were a handful of times when I got a loud clicking noise which sounded a bit like a FM static mixed with digital distortion on a scratched CD. I’m not sure what prompted this to happen as I was stationary at the time. It only happened a handful of times during my many hours of testing, but I’d much prefer that it didn’t happen at all. Another issue was that I intermittently got a faint high pitched buzz in the right channel. It sounded the worst with my extremely sensitive LiveWires, and was actually quite a distraction on some music. On most other headphones it was not much of an issue. I likened it to the hiss or hum that I have on some of my other amps, and it is much more difficult to notice when music is playing. In fact I almost think it goes away all together when music is playing, but I have to confirm that with more hours of testing.
Speaking of hours, I should address the battery life. On the Ebay listing, the seller advertises 6 hours maximum battery life. But on the side of the box it says 3.5 hours. My real world usage averaged somewhere in between those two figures depending on headphones used and volume level. That doesn’t sound like much until you consider that this unit is not only acting as an amplifier but also a receiver and DAC all in one. I don’t know of another product that does those things on battery power so I can’t say this unit is substandard in that regard. I can only mention that the battery life ended up being less of an issue than I originally anticipated. I could easily watch an entire film, even a really long one, and still have juice to spare. I ended up just charging it a few nights a week, and that worked well for me.
Here are my impressions of sound quality using various headphones:
Equation Audio RP-21
These cans are fairly easy to drive, and they sound about as good as I’ve ever heard them on the JCH-A2. Their strong point is bass and there is plenty to be heard here, without any extra bloat or sloppiness. The soundstage is, as usual, somewhat limited, likely a consequence of their closed construction. But everything else is top notch to the point where you almost wonder how it could possibly be improved. That is, of course, only until you listen to a truly high end headphone. Still, there is a lot to like here and the JHC-A2 is a very good match. The only complaint is the maximum volume is somewhat limited. Not that I would often listen at such high levels, but it could be a problem for a small amount of music.
LiveWires Trips
As I mentioned before, these are highly sensitive. More than 50% of the time I get the high pitched buzz in the left channel. I have so far been unable to pinpoint what is causing this issue. I suppose I could unplug all my wireless devices and see if that solves it, but that has not been possible so far.
Other than that the Trips sound pretty good with the A2. There is a nice warm sound signature with plenty of detail. Bass is good but seems just a tad rolled off compared to how it sounds when used with higher end equipment. Highs suffer similarly, by losing just a touch of that sparkle that makes these truly great IEMs. In the case of the highs, it might be a blessing in disguise because the Trips can be ruthlessly revealing of any sibilance or harshness. Of course, it is hard to determine if this is caused by the DAC or the amp section. There is no problem with maximum volume here though; it gets as loud as you could possibly want.
Sennheiser HD600
The classic HD600 has developed a bit of a reputation as a difficult to drive headphone. The JHC-A2 is quite capable of driving them very well, although the result is not quite among the best I’ve heard. Still, the performance is pretty solid, with very nice imaging and great dynamics. I was especially impressed with the micro detail that I heard on some more delicate jazz tracks. The HD600 seems under rated when it comes to detail recovery, and this DAC/amp helps show that fact.
Compared to my Vivid Technologies V1 portable amp, the JHC-A2 sounds somewhat laid back and mellow. It’s very good, and in fact might be preferable depending on your mood and the program material, but it is not as exciting. Female vocals can sound like they are farther back in the mix, and male vocals gain an added heft.
Beyerdynamic DT-990 600 ohm
This is one headphone that isn’t a great match for the A2. I like the presentation of the high quite well, in fact the slight rolled off nature sounds better here than with many other amps. But the bass doesn’t sound quite right. It seems to have a lack of authority which changes the usually lovable nature of these cans. It almost feels like the 990s are doing an impersonation of the 880s, and it is a bad impersonation. What sounds clear and neutral on the 880s seems limp and thin on the 990s.
In defense of the A2, the 600 ohm DT990s is kind of a bear to drive. Many an amp has tried and failed with these things so I don’t think it is a dealbreaker.
Beyerdynamic DT880 250 ohm
Now that’s more like it. The A2 controls these things very well, with a lush and silky midrange that is not always present with lesser amps. The thing that jumps out at me is how quick this combo sounds; transients on tricky material like Brain from Hiromi sounded spot on, and even simple things like the string across a cello sounds vivid and lifelike.
Without being able to separate the DAC from the amp section, I’m going out on a limb to say the DAC is pretty revealing. It’s also fairly even handed and neutral, excelling at all types of music. The amp section is basically more of the same, and aside from feeling like it sometimes runs out of steam a bit early, it really satisfies all the requirements that a lower-mid level amp should. I don’t mean that as an insult: I’ve heard $500 amps that don’t perform as well. I’ll be doing a lot more listening with these because they sound very nice with this amp.
Ultimate Ears Super Fi 3
These are classics in my book. They remind me of a decent bookshelf monitor, in that there is not a ton of bass but what is there is nice, and for me they give an interesting perspective on the music that not many IEMs or headphones can give. I think it’s because they are somewhat less accurate than most of my IEMs, and they force me to focus on the performance to enjoy it rather than just letting me sit back and relax. That sounds kind of silly but that’s how I feel. Obviously they are not the best at many things but are a good tool none the less.
The A2 is simply brilliant with the SF3. I don’t think there is a single area that could be improved. Switching to the Matrix M-Stage or the DarkVoice 337SE doesn’t seem to do anything to make them sound better. Maybe they are just maxed out, and it is caused by the limitation of the SF3 rather than the prowess of the JHC. Whatever the case I’m enjoying the “synergy” here.
CONCLUSION
This is far from a final conclusion, as I will be spending time with this product and adding to this review as time goes by. But it certainly is an interesting item. I think the most fun I’ve had with it is from watching movies. The slightly laid back presentation goes very well with most movies and soundtrack material, and the ability to do without messy wires is a joy.
The JHC-A2 sounded better than most of the headphone jacks on my gear. I have a few higher end items like vintage McIntosh and pricey Marantz that edge out the A2, but not by much. Using the analog input on the A2 only slightly degrades the sound quality, shrinking sound stage and making things a bit too dark compared to the digital inputs. This must be due to the extra ADC process that is introduced by doing this step. Still, I appreciate the fact that the analog inputs are there, and I often found myself utilizing 3 of the 4 inputs during testing. USB is still something that I need to spend more time with.
The novelty of this product is the fact that it does something I’ve never seen done before. Once you get over that you find yourself with a very nice little DAC and matching amp. If I had paid the $250 for a DAC and amp (either a combo unit or separate pieces), and achieved this sound, I would be pleased with the value. The fact that it all happens wirelessly makes it even better.
More to come when I get time.
PS I didn't know where to put this as it is sort of portable, and also considered a source, and could even be computer audiophile related..... so I just chose here.
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