I first became aware of the Cayin brand some years ago as a neophyte to the Head-Fi hobby when a friend bought a C5 portable headphone amplifier.
Driving a pair of Beyerdynamic DT880 250 Ohm headphones, this svelte and well built powerhouse performed brilliantly, to my surprise it must be said.
It was the best of it's kind then, making comparable Fiio offerings seem anemic by comparison, and it remains a contender now.

Fast forward to present day, and Zhuhai Spark Electronic Equipment Company, better known as Cayin for the past 20 years, has rightly earned a serious rep in the community for their impressive tube amplifiers and DAPs. They do however also make a solid state, fully balanced headphone amplifier, the iHA-6, the subject of this brief review.

I felt compelled to air my impressions, not because Lumous Audio, in their wisdom, decided to loan me a unit for a while to "get my opinion" but because it is the finest sounding headphone amplifier I've heard south of twenty grand South African (about USD$1300).

More amazing is that it retails for a ZAR shy of half that (at the time of writing).
So I've gotten to the punchline upfront: it's a stellar performer, and it did not take long for me to come to this conclusion.

Out of the box one is struck by the solid mass of the thing, only 7 by 24 by 25 centimeters but weighing in at a dense 4 kilograms.
4mm thick aluminum panels are nicely finished in silver with nary a screw in sight.
Upfront one finds no less than 4 different headphone outputs covering low and high impedance 6.35mm and both 3 and 4 pin balanced XLR connectors by Neutrik.
The "low" has an output impedance of 10 Ohm whilst the "high" is 120 Ohm. More on this anon. The balanced outs both present a load of near as dammit Zero Ohm.

An illuminated power button resides next to three push-buttons for selecting RCA or XLR analogue inputs, high or low current delivery and low and high gain respectively.

The ability to increase the amp's quiescent current is a very neat trick too. Power output is decreased slightly while current delivery is increased.
This works very well indeed on low impedance headphones, and can be very noticeable or not so much, headphone dependent.
This should be the default mode for most Planars.

A large, onyx fronted silver knob controls the very smooth ALPS RK27 Blue fully balanced 4 way pot.
Since there are no pre-amp functions the rear panel is spartan, housing one pair each of RCA and 3 pin XLR connectors along with the usual IEC power socket.
I might mention that build quality and component choice are both excellent, and not just "at the price" - at any price.

Switching on one notices that the illuminated power button blinks three times and then settles into a constant white glow.
Protection against DC offset on power up. Nice. My headphones thank you. They don't need to be unplugged, ever.

Having given it 5 minutes to warm up I connect the trusty Sennheiser HD6XX to the 4 pin output on low gain and low current settings.
Source is a Windows 11 PC connected via AQ Pearl USB to Resonessence Concero DAC and thence single ended to the iHA-6 which coverts the signal to fully balanced internally using a bridge-tied load (BTL) circuit that converts single end input to balanced before feeding into the amplification circuit. Any signal loss via this process is said to be inaudible.

I almost always start listening with the HD6xx (and previously HD650) - since I know its sound so intimately, I can almost immediately hear where an amp is at based on this synergy. And synergy there certainly was! Santana's IV album in 24/48 FLAC sounded full, detailed and engaging at moderate volume - around 10 on the pot.
Absolutely no need to use high gain, the Cayin outputting a handy 1.2W into 300 Ohms...did I mention this thing is POWERFUL??

Andy Kong uses both the HiFiMan HE6 and Abyss 1266 to demo the iHA-6 at shows. Two of the most difficult to drive (properly) headphones on the planet, and this in front of a rabid and knowledgeable crowd...either a very brave man or very certain that his amp can do justice to these two behemoths.

Power is the last thing an owner needs to worry about, so let's put that to bed: 7W @ 32 Ohm balanced, 3W @ 120 Ohm and 600mW into 600 Ohm.
According to the Rolls Royce Scale, sufficient. Oh boy, is it ever sufficient..!

I have not needed to use the high gain setting (+12dB) at all, and that should speak volumes.

All that power is delivered with a velvet glove-like delicacy though, refined and smooth when required but capable of huge bursts of dynamic range and slam without any hint of compression or clipping. I simply loved the way it allowed the HD6xx to sound better than I've ever heard it, and I've heard it from MANY sources.

It is well-known that the venerable Sennheiser scales with better equipment and this absolutely holds true here.
There is no "veil', perceived or otherwise.
Midrange is rich and full-bodied as it should be and in fact all frequencies are evenly presented.

Similarly it gets the best out of all my headphones, from HE400SE to AKG K701 to Fostex TH-X00.
Three very different headphones, all of them fully and authoritatively driven.

I heard detail from the HiFiMan I didn't know it could resolve.
Bass on the power-hungry AKG filled out and became...more...and better defined, with seemingly much less roll-off.
The 25 Ohm Fostex is sensitive and easy to drive and the iHA-6 allowed me to experience what it could really do when subjected to massive power, current and control.

This headphone just thrives on current and with the amp in high current mode it's the best I have heard them.
They deliver legendary bass but now it's even better defined and there seems no end to its extension.
Highs in particular have even better extension with nary a hint of sibilance.
Considering that the Mahoganies have a tendency to sound a bit "zingy" with the wrong amplification, this is impressive control.

Whilst I would not call the iHA-6 a reference amp (it is ever so slightly warm of neutral), compared to the Topping A90 I found it to be more "musical". Not easy to quantify but noticeable once one has had a decent listen - for "musical" one might substitute "organic" or 'natural". Listen to Amber Rubarth's "Sessions from the 17th Ward" on DSD and you'll quickly understand the difference.

Perhaps the only negative about this amp might be the high output impedance of the SE headphone jacks, but truthfully its a non-issue for me. It is designed to deliver as a fully differential device and should be used that way.
In short, it sounds great running SE, but it is exceptional when used balanced.
'Nuff said!

I could ramble on, but I've got too much music to listen to...the honeymoon is not yet over.
It is all the headphone amp most (normal) people should ever need and redifines the cost to performance ratio in my book.

I love switching it on every day and can highly recommend it.

UPDATE 08/04:
Having now had the opportunity to hear my HD6xx using the 120Ohm SE output I will need to change my initial opinion.
This is in no way a con now that I understand why it's there in the first place, rather a stroke of genius from the designer(s).

As per my thread post:

There's definitely a heftier, rounder bottom end but no bleed into mids and no loss of detail (not that the HD6xx is the most resolving headphone to begin with).
Yes, it's a tad warmer but I like it!
Yes, I would say slightly more euphonic (ok, tube-like) which was precisely the result I was hoping for.
HF seem to be largely untouched, but that's perhaps due to me not hearing much above 13kHz...
I will need a bit more time to hear if I can pick up on any LF nasties, but so far, so good.

Cayin iDac-6 and iHA-6​

 

Prequel​

 
Let me rewind just a tad before we begin. I am one of many who interminably chase the "perfect" sound. Saying that might make it easy to understand how joyful I get when trying out new products. I always keep my radar on for a resonating blip of new gear and new manufacturers. I have progressively had my eye on Cayin as a company and with their unique DAP designs, friendly staff and great reputation - How could you not!? Cayin is a Chinese company really pushing for the western market and who's to blame them? My only experience with Cayin's products before now was a quick listen to their Spark N5 portable audio device which really impressed me. I actually owned a much more expensive DAP at the time and I truly thought the N5 was much better for much less money. Ever since this moment, Cayin has transitioned to the back of my head and nestled there until my thirst was somewhat satisfied with their new desktop duo. Cayin was kind enough to send me their iDAC-6 and iHA-6 for a listening period to review. After some listening sessions I will wistfully return both products.
 
 

Initial Impressions​

 
So right out of the box, I picked up the DAC which felt very robust and satisfying in the hands. A compact device with a sleek, modern and professional look. It feels heavy in the hand despite being small, which can be credited to the premium metals in the design. Running my fingers across the three option buttons in the center give a rather loose feeling, but nothing significant. The large knob on the right front panel has a black center and looks to be a nice matching metal and plastic addition to control volume and menu options. The headphone amp was right underneath in the box and pulling it out was almost an identical experience. Premium feel and matching color scheme and build material. A slightly more populated front panel with not 1, not 2, but 4 headphone outputs. Although these are two separate products, Cayin's marketing and even the products themselves simply yell "dynamic duo". It's a very stackable and compact arrangement of gear which look superb on a desk while not taking up much real estate, which I believe was the whole concept behind their creation in the first place. This also led me to combine my review instead of separating them, but as you'll see later on.. You can still enjoy these siblings individually as well. 
 
 

Technology & Design​

 
Cayin iDac-6: A particularly unique DA converter is the iDac-6. Right from the beginning I was very interested in this desktop device for many reasons. The most obvious reason being, like the iHA-6: a small form factor and quiet but pleasing appearance. The standout attribute for the iDac however is the integration of tubes. Tubes glorious tubes! Before we jump into that lets go over the specs:
 

As you can see, this DAC is fairly impressive from a technical standpoint. To be fair however, I will say that it is increasingly more common to see great specs from much cheaper devices these days. It isn't rare at all to find dual dac chips slapped on a PCB with low distortion, DSD compatibility and a few gimmick features. Essentially that is exactly what is going on with Cayin's iDac, but with a few more unexpected bonuses such as a user selectable tube stage option (on the fly) and a few other things that slightly set it apart. The chips used are the AK4490 which is a very good chip capable of beautiful sounding native 2x DSD as well as up to 32bit/384khz PCM.
 
Having owned many DACs in the past, I have a lot to compare the iDac to (both from memory and in person). The thing I like most about both of these products are their size. I think this is the smallest high end DAC that I have had the pleasure of using. It is really appealing for people who listen to music at work or on a desk at home as the small footprint barely uses any space. It looks very nice without standing out and can plug right into your laptop - while coworkers or family members gaze in envy. I should also mention that I like to use Linux as my operating system on my computers and one thing I will thank Cayin for is its compatibility. Usually it is always "plug and play" with most products, but recently I have run into problems with a DAC not being compatible - so it is worth mentioning that the iDAC-6 works flawlessly with Ubuntu and Linux Mint.
 
The iDAC-6 has RCA outputs as well as 3 pin balanced outputs. Standard USB type B port, coax, AES and optical for your inputs.
 
One feature I would have liked to see here is a power-save option. Although the four 6N16B tubes integrated in the DAC have a long-lasting 10,000 hour lifespan.. I would like the peace of mind knowing I could offer a more optimized and energy efficient quality of usage. I tend to do most of my listening at night and I have fallen asleep more than once while leaving one of my tube amps turned on. It's just a bad feeling, no matter how insignificant the overall affects are. My McIntosh MHA100 actually has this feature built in and it is a pure solid state device. I like knowing that if I fall asleep or forgetfully walk away that my headphones and amp won't be constantly running for hours or days. For the record, you can easily turn this off on the MHA100, which you may want to do if you were looking to burn in a new pair of headphones.
 
Overall the specs are great and the implementation of the quad tubes make for a uniquely magical fully balanced machine.
 
Cayin iHA-6: Here is what I could find for the specs on the iHA-6. It should be noted that it is really hard to find any official documentation regarding these two products. It looks like they haven't yet been added to Cayin's official website yet and I guess them being so new contributes to the lack of information online.
 
 

 
Another case of expectedly pleasing and common specifications. Low distortion and a frequency range well beyond our hearing capabilities. I like the fact that you can choose to have a lower or higher gain setting. This amplifier will certainly give you the juice needed for power hungry headphones being 7W @ 32 ohms as well as accommodate the more efficient headphones or in-ears. The design, just like the DAC, is sturdy and premium. A sandblasted metal housing (which should also help with EMI resistance) surrounds the inner workings. The iHA-6 gives the option of balanced or unbalanced, but the jump from an output impedance of 10 ohms (low) to 120 ohms (high) is slightly off-putting. Coming from a McIntosh MHA100, I had the luxury of 6 different options for matching the power perfectly with what I was using. My Grado RS2e for instance is somewhere in between the two settings of Cayin's amplifier and I felt a little uncomfortable using either low or high. The balanced output however is a much better story. I found myself using it almost exclusively in balanced mode using my LCD-4's and boy did it power them pleasingly. Balanced has a mere .3 ohm output impedance which really makes it perfect for almost anything.
 
 

 
 
Conclusion: The overall technology and design did not leave me feeling like it lacked anything in particular and in fact I felt a little pleasantly surprised. I love the modern aesthetics and the hybrid tube design in the DAC is especially neat. Both make for a fully balanced solution in a small form factor with more power and features than you'll know what to do with. The only thing I would like to see from a design standpoint is perhaps sturdier feeling knobs and buttons and technology-wise I think a power save option would be a nice extra bonus. Perhaps having better impedance matching would be nice, but honestly my RS2e and even a few of my IEMs sounded just fine with the right volume. Pretty, potent and plentiful.. thats the name of the game with these two. I think Cayin did a good job making these look good and filling a niche in the market. I had some gripes, but to be honest both devices have more features and options than most of their comparable counterparts. I think anyone would be proud to display these two atop their desk or rack.
 
 

Sound & Pricing​

 
Sound: Let me start off by explaining a few important things. I am definitely an objectivist and one of those guys who blind tests before making any outstanding judgment or recommendations. To me, a DAC is certainly one of the last things I would look for when upgrading my sound. I even have trouble distinguishing most amplifiers, especially those which are solid state. That is not to say I have bad hearing either - my ears test rather well and I can usually hear hiss/distortion extremely easily (especially with IEMs). This quality is stressed even more when paired with the fact that both the iDAC-6 and iHA-6 have a very neutral and uncolored sound. I do however think they perform exactly how they should in the fact that they let the music speak for itself. There is no crazy distortion or internal DSP going on with these devices although you do have the option for a handful of filters on the iDAC, as well as a tube stage. If I am being honest though, the tubes were a slight disappointment. When swapping back and forth using an RCA connection (again the only way to do both tube and SS), it was extremely difficult to notice the difference - and this was with me swapping them myself! When doing it blindly I especially had trouble recognizing the filters and tube stage affects on sound. This can be considered a good thing to a lot of people though. If you just want a very transparent and accurate sound signature out of your gear then this is exactly what you want. When listening to my LCD-4's I noticed very good synergy. I think the LCD-4 is a pretty warm headphone and paired with the neutral and open sound of Cayins amp/dac combination I found myself really enjoying the results. The total lack of coloration with the tubes sort of begs the question though. What is the point? I know most people would want to buy a hybrid DAC for the slight musical distortion, but it was extremely hard for me to hear much if any of that at all. These impressions aren't to sound too critical however, because I did do some interesting comparisons and mismatching which left me actually pretty satisfied.
 
 

 
 
LCD-4: With the combination of both of Cayin's offerings I thought the sound was very good actually. I definitely have used these LCD-4's with some world class components and I didn't feel like I needed "more" of anything. I found them driven quite well using the four pin balanced connection and even used the HIGH level of single ended configuration with satisfaction. The only time I felt them needing more juice was when I experimented with the LOW port, which obviously isn't meant to drive power hungry planars. The bass was nice and punchy, mids were accurate and detailed and the highs were crisp. If I used some imagination I could call the signature slightly cold, as you expect that warm enveloping sound from the tube stage, but you never really got that. However, because these Audezes already give you a very laid back sound to begin with, I thought the pairing was just fine.
 
RS2e: I really love my Grado RS2e. It really is a great sidekick for the LCD-4 in that they have a differentiating sound and at different price points. Listening to the duo with my pair of Grados was another positive experience. Gregory Porters latest album really had me respecting these little devices more and more. With the RS2e's I did feel like I heard a little more of the lushness seeping into the midrange on the tube setting. The bass seemed slightly more euphonic than I had remembered it being and the instrumental treble was very impressive. I tended to use the LOW single ended option with these headphones and I did have to turn the nob up slightly more than you'd expect, but it definitely drove them as loud as I would want them and still with decent headroom. I liked this combo a lot.
 
Compared to McIntosh MHA100: So comparing to my main setup, the difference was pretty clear. Now I will say that the MHA100 retails for about double the price of these two, so the comparisons are to be taken with a grain of salt. The MHA100 is a solid state amplifier that sounds like one of the most "tube sounding" solid state offerings I have ever heard. I think McIntosh really used some heavy filtering and tweaking, because this device sounds nowhere near neutral or cold. I happen to love this amp/dac combination from McIntosh a lot and for many different reasons. When swapping to the Cayin units I immediately missed a few things.. The bass gain option, the darker sound and the powersave feature. I think the features on the MHA100 outshine Cayin completely here and I haven't even mentioned the proprietary analogue crossfeed that give a speaker-like representation with the MHA100. Looking at purely the sound I will say both are different, but good. If you happen to prefer an uncolored, unmodified amplifier and just want a great, detailed and accurate sound then I would definitely look at the iHA-6. It sounds very much how a high end solid state amplifier should sound.. comparable to something like the Auralic Taurus or even Schiit's Ragnarok. I found myself grabbing my darker sounding headphones when listening to the Cayin duo and my brighter Grados with the McIntosh. The solid state amplifier coupled with the tube DAC create a sort of detailed musicality that really bring my headphones to life. It is sort of ironic how a tube DAC sounds a lot less warm than the solid state MHA100, but that is what I have found through the comparisons. I would only say that the unique features in the MHA100 outshine Cayins offerings, but the sound itself were almost equally enjoyable and impressive albeit slightly different.
 
Compared to LH Labs Vi Dac Infinity: I actually pretty much enjoyed both of these the same, if maybe the Cayin duo more. Both amplifiers can power just about everything I throw at them with pretty impressive headroom. The Vi Dac is again about double the price, but sound-wise I believe it is very easily in the same league as both the iHA-6 and iDAC-6. If anything I think the filters and tubestage options on the iDAC made it a lot more impressive. I certainly found the filters almost inaudibly different, but they were slight enough to make things interesting. Features in general wasn't even a contest as the Cayin combination have many more options and outputs. I should mention the size as well, because the Vi Dac Infinity definitely isn't something you can just slap on top of a desk easily. It takes up a lot of space and looks slightly out of place amongst non high end audio components. You can stack Cayin's combo right on top of almost anywhere and the subtle but sleek appeal serves as a very versatile complementation. The sound is very similar and both have fully balanced architecture. The only real difference is the variation of DAC chips as I believe the Vi DAC uses reference Sabre chips. My few select DSD files also played natively on both devices as well. I think I would recommend saving your coins for something else and going for the Cayin units if it were a choice between these two. Really great stuff from Cayin!
 
Cayin iDAC-6 with MHA100: As I am one to mix and match and try new things - it was inevitable that I tried pairing some of my components with their gorgeous Chinese counterparts. I think the best experience I had with reviewing these devices was when I paired Cayin's DAC with my McIntosh MHA100. The sound was great and I got amazing options combining the two together which made for a really nice experience.
 
 

 
 
The ever so slight lushness of the tubes seemed to be a little more apparent when combined with the McIntosh as the pairing made both sound a little warmer and more enjoyable than I had remembered. Having several different filters and gain on the iDAC, along with the tube and solid state options made for some really nice experimentations. The MHA100 has bass boost options of up to +12dB at 40hz and an analogue crossfeed that make for a ton of fun with Cayins DAC. At the end of the day I much preferred this combination and it made me really consider getting the iDAC for myself to go in my system permanently.
 
Price: The price of both the iHA-6 and iDAC-6 are about $1000 USD each. I think both of these products fill a very specific niche in the market and the prices kind of ride the line between high end and mid-fi. I think these devices aren't overpriced for the performance and craftsmanship offered, but I think Cayin would have sold a lot more units if the price tag was slightly shrunken down. Overall you definitely get what you pay for and I think the pricing is probably more than fair.
 
 

Closing Thoughts​

 
I really enjoyed my time with both the iDAC-6 and the iHA-6. The best situation for someone to buy these is if they have limited desk space or don't want huge devices getting in the way.. all while gaining a modern stylish look of audio products with excellent sound quality and a few niche bonuses such as a quad tube DAC. I didn't mention before that these little offerings pair well with a broad selection of IEMs too. My Kaiser K10's especially were driven correctly and sounded as perfect as they ever had. I only very faintly heard a whisper of hiss-like distortion due to the sensitivity of the K10's, which is completely expected. These are very versatile, sound just as good as much more expensive equipment and I think anyone would be proud to have these in their inventory. Well done Cayin!
 
 
 
 
-Writing and review by Dillan-
-Photography by Regan Hulvey-

CAYIN iDAC-6 & [size=24.57px]CAYIN iHA-6 [/size]​

REVIEW​

edited review dedicated to the iha6 alone here