Cayin C9: Dual Nutube, Fully Balanced Class A/AB Portable HeadAmp

[bluestorm1992]

Hmm. So I just got the Sennheiser IE900 and the Cayin C9 this weekend. I have an LCD-3 non-fazor as my only full-sized headphone and it is hard to drive.

I wasn't expecting much from the Cayin despite it's high price tag. To be honest, it seemed like the flavor of the last few months in head-fi. It doesn't have a DAC which means you have to stack it with something else. It's being pushed as a solution for IEMs, but IEMs don't usually require much power. So, I expected that it would be a quick return. There were certain aspects of it that I liked a lot - the replaceable batteries are a rarity in today's market. I LOVE tubes.

My first impressions were on appearance alone. It.is.huge. I've had the WA11, Diablo, and many other large portable amps from Ray Samuels and hifi m8. This feels like a brick. So many inputs, outputs, and switches. I couldn't see myself taking it anywhere.

I tried it with the Sennheiser IE900 and the Hiby R8 and it sounded slightly better that just the R8 but not life-changing. However, when I tried it with the LCD-3 on High Gain, I was blown away. Literally, nothing I've heard (including fully upgraded WA7 + WA7TP) sounded as good. Bass hit deeper, the soundstage was expansive, and there was power and control in the volume pot.

I immediately looked for the case and ordered it on eBay. This will be in my collection for a long, long time. I know this post contradicts the last written assessment, but clearly I found some synergy between my favorite headphone and the C9.

Congrats!

Just a short note, the source plays an important role in the overall synergy. In my listening session with @tawmizzzz, we tried out C9 with Traillii with two DAPs: R8 and N6ii (A02); according to @tawmizzzz, R8 as the source makes the sound “too grand”, but A02 gives the right balance of being musical, engaging, and the huge soundstage.

Not trying to sell A02 of course; R8 is a great DAP and many C9 users choose it as the source. Just trying to note that on the synergy between C9 and the IEM/headphone, the signature of the DAP plays a huge role as well. It seems that R8 is exactly the source you need to pair with LCD3.

 

[bluestorm1992]

A further note on driving full-size headphone from C9; my experience is mostly based on Abyss Diana V2 and I want to talk about it’s synergy as well. Before C9 I was using the Xiaudio Broadway Amp (balanced version). This is recommended by Abyss themselves to be THE BEST pairing with Diana, and I was also extremely satisfied with the performance of this pairing. Note that the Broadway is even more expensive than C9 (it retails for $2250) and also runs on 18650 batteries.

I got C9 without the intention to replace the Broadway amp, but rather to just add a transportable solution. However, upon careful A/B between C9 and the Broadway amp, I could not tell a big performance difference between the two. Surely the timbre between the two amps are different, but in terms of the overall performance in driving V2, they are remarkably closed. So the decision was simple for me, I sold the Broadway amp and the pairing desktop dac.

Not trying to approve or disapprove any points here, but simply to share my (limited) headphone pairing experience with C9. Apparently, synergy is important, and when you get it right C9 gives an extremely rewarding experience for both IEMs and headphones.

 

[bigbeans]

Hmm. So I just got the Sennheiser IE900 and the Cayin C9 this weekend. I have an LCD-3 non-fazor as my only full-sized headphone and it is hard to drive.

I wasn't expecting much from the Cayin despite it's high price tag. To be honest, it seemed like the flavor of the last few months in head-fi. It doesn't have a DAC which means you have to stack it with something else. It's being pushed as a solution for IEMs, but IEMs don't usually require much power. So, I expected that it would be a quick return. There were certain aspects of it that I liked a lot - the replaceable batteries are a rarity in today's market. I LOVE tubes.

My first impressions were on appearance alone. It.is.huge. I've had the WA11, Diablo, and many other large portable amps from Ray Samuels and hifi m8. This feels like a brick. So many inputs, outputs, and switches. I couldn't see myself taking it anywhere.

I tried it with the Sennheiser IE900 and the Hiby R8 and it sounded slightly better that just the R8 but not life-changing. However, when I tried it with the LCD-3 on High Gain, I was blown away. Literally, nothing I've heard (including fully upgraded WA7 + WA7TP) sounded as good. Bass hit deeper, the soundstage was expansive, and there was power and control in the volume pot.

I immediately looked for the case and ordered it on eBay. This will be in my collection for a long, long time. I know this post contradicts the last written assessment, but clearly I found some synergy between my favorite headphone and the C9.

I have found the C9 to be excellent with my headphones: MDR Z1R, Empyrean and Stellia. It’s an excellent companion for both iems and efficient headphones.

What I found interesting is Sony optimized MDR Z1R for TAZH1ES and DMPZ1 which are both less powerful than C9. At CanJam 2019, I saw ifi demo Stellia with a ifi Nano black label to demonstrate that it is plenty for Stellia despite having far more powerful gear at their show table.

I think devices like Shanling M30 (and EM5 as well) and C9 represent two new future approaches. A premium all in one system or something more modular like C9 that can scale and change based on the DAP you pair it with.

While I could get more performance with a full desktop amp, I have been looking to simplify my desktop setup and focus on gear that can serve multiple needs. As headphones are moving to becoming more efficient I think the C9 will become can be a versatile gear for many years to come.

 

[HiFiHawaii808]

I have found the C9 to be excellent with my headphones: MDR Z1R, Empyrean and Stellia. It’s an excellent companion for both iems and efficient headphones.

What I found interesting is Sony optimized MDR Z1R for TAZH1ES and DMPZ1 which are both less powerful than C9. At CanJam 2019, I saw ifi demo Stellia with a ifi Nano black label to demonstrate that it is plenty for Stellia despite having far more powerful gear at their show table.

I think devices like Shanling M30 (and EA5 as well) and C9 represent two new future approaches. A premium all in one system or something more modular like C9 that can scale and change based on the DAP you pair it with.

While I could get more performance with a full desktop amp, I have been looking to simplify my desktop setup and focus on gear that can serve multiple needs. As headphones are moving to becoming more efficient I think the C9 will become can be a versatile gear for many years to come.

That's the key choice. Do you want one system that can support IEMs and Headphones and is transportable with tube sound? If the answer is yes, then building a system around a C9 makes a lot of sense. That's how you maximize the utility and value of the C9. If you want the best price-performance for each use case, C9 is still worth it for the transportable use case, but you can get better truly portable or desktop solutions to go along with it. Or, you can skip the C9 altogether and get a full desktop solution and a full portable solution. These are the choices people are discussing and they all make sense. So, to make the right choice, you need to consider your entire set of use cases and how you want to optimize them.

 

[DarginMahkum]

Surely the timbre between the two amps are different, but in terms of the overall performance in driving V2, they are remarkably closed.

What is the difference in timbre?

 

[lucasratmundo]

I continue to love the C9 but I really wish it had a “desktop mode” that allowed me to have it continuously plugged on the wall.

 

[soundblast75]

My 2 cents here is that C9 will never ever be the weak link in your chain

 

[Andykong]

This is good to see, thanks. Can I ask: is there any danger in using a 40W QC supply to charge the batteries? I assume the 40W charger will convert to 18W but just want to be sure...

Although 99% QC compatible USB charger are QC3.0 based, you must clarify this before we move on.

QC3.0 supports 3.6V~12V, maximum 18W quick charge, C9 adopts 9V/2A which is a fairly common option in QC3.0. Theoretically all properly implemented QC3.0 charger will support 9V/2A devices, but on the safe side, please check the user manual or your supplier just in case.

So where is the 40W comes from? That would mean your charger has multiple USB connectors and can charge up several USB devices concurrently and can provide up to 40W maximum charging power. In other word, the maximum charger power to ONE QC3.0 device is 18W, but you can charge TWO QC3.0 device or ONE QC3.0 plus TWO 5V/2A device at the same time.

 

[Andykong]

I wonder, can the battery tray be purchased with the OEM batteries?

We cannot bundle 18650 batteries with the battery module as an factory option, that would complicated the logistic dramatically. If we ship the battery module with lithium battery, the international shipping cost will increase 3-4 times. So unless your local Cayin dealer sells 18650 batteries in their shop and they can make a bundle for you, you have to order the battery separately.

 

[Andykong]

Could the Luxury & Precision W2 be used as a source? I'm assuming it can't be a good one because there is no line out mode, but if you guys have any thoughts, I would love to hear them. A Phone -> W2 -> C9 seems like a semi-decent idea although I'm more likely to get a standalone DAC or a DAP with line-out.

I'll quote this answer for your reference.

 

[Nostoi]

Although 99% QC compatible USB charger are QC3.0 based, you must clarify this before we move on.

QC3.0 supports 3.6V~12V, maximum 18W quick charge, C9 adopts 9V/2A which is a fairly common option in QC3.0. Theoretically all properly implemented QC3.0 charger will support 9V/2A devices, but on the safe side, please check the user manual or your supplier just in case.

So where is the 40W comes from? That would mean your charger has multiple USB connectors and can charge up several USB devices concurrently and can provide up to 40W maximum charging power. In other word, the maximum charger power to ONE QC3.0 device is 18W, but you can charge TWO QC3.0 device or ONE QC3.0 plus TWO 5V/2A device at the same time.

Thanks for the reply. Here's a close up photo with the specs on. Actually says, total output of 63W. It can certainly charge my laptop, and doesn't seem to have any issues with my C9 or my phone. Haven't tried my N6II on it yet, but wanted to make sure there's no risk.

Info:

The top port offers a lower power of 18 watts.
The bottom port offers 60W.
If two ports connected, bottom port is throttled to 45w.

Basically my question is: is it okay to charge the C9 via 60W?

The precise model is AUKEY PA-D5.:

 

[Andykong]

Howdy all. Soon to be new C9 owner. Question...I have previously used a PWAudio 3.5+4.4 to 4.4 pigtail with Sony WM1A to Woo Audio WA11. If I recall correctly, the pigtail was highly recommended to prevent causing damage to the WA11 because of Sony's grounding or lack there of the 4.4 output. Is there ANY reason to use or not to use the pigtail with the Sony to the C9?

Same question but with the C9 and a Hiby R8 using 3.5+4.4 out to 4.4 in. Will it help, do nothing or cause a big explosion?

Thanks for any help.

I'm using a WM1Z without a pigtail, using the Pre mode, with no problems. With a short interconnect, C9 will work with grounded or ungrounded, as I recall AndyKong stating in a previous post.

Thank you!

Just so I fully understand. The pigtail is not at all needed but it would be ok to use it since I already have it?

You can use the pigtail if you wanted to, but it is not required technically. I suggest you try your C9 and Sony WM1A without the pigtail for several days, when the sound of your system become stable and you are very familiar with it, add the pigtail to find out which is the better connection to your ear.

 

[Andykong]

Thanks for the reply. Here's a close up photo with the specs on. Actually says, total output of 63W. It can certainly charge my laptop, and doesn't seem to have any issues with my C9 or my phone. Haven't tried my N6II on it yet, but wanted to make sure there's no risk.

Info:

The top port offers a lower power of 18 watts.
The bottom port offers 60W.
If two ports connected, bottom port is throttled to 45w.

Basically my question is: is it okay to charge the C9 via 60W?

The precise model is AUKEY PA-D5.:

This is NOT a QC3.0 charger, this is PD charger, a different charging protocol and is NOT compatible with QC3.0. The USB-C Out 1 supports PD 18W, not QC3.0 18W. I don't recommend this charge for C9.

 

[Nostoi]

This is NOT a QC3.0 charger, this is PD charger, a different charging protocol and is NOT compatible with QC3.0. The USB-C Out 1 supports PD 18W, not QC3.0 18W. I don't recommend this charge for C9.

Oh OK. Good job I I asked. I'll change it. Could it have done damage?

 

[Andykong]

I just got home last night after a long trip away. So, the first thing I wanted to do is try out my C9 with all of my full sized cans. After spending so much time with IEMS over the last few weeks, it's really nice to hear full sized headphones again. First and foremost, the C9 pairs the best with the Hugo 2 for full sized headphones. My Hiby R6 2020 isn't high quality enough to really achieve their full potential and it is very striking how much so. I need to find a DAP that pairs with the C9 as well as the Hugo 2. Any recommendations?

Anyway, I've been listening to HD 800S, ZMF Verite Closed, Hifiman Ananda and Focal Clear. All headphones benefited significantly from the pairing with the C9. The HD800S gets a better bass response to go along with the huge sound stage and overall clarity. Still can't beat them for Classical Music and Jazz. Bass response isn't good enough for other genre relative to the alternatives.

ZMF VC really gets to the next level with the C9 + Hugo 2 as I reported before. I had family and friends listen to the VC and they all universally said this was the best headphones they have ever heard. They wanted to know it's price to get one for themselves. They took a pause when I told them. The detail and richness and 3D presentation of the sound is really striking. My friend said he had never heard guitar plucks before in the songs he listened to.

The Hifiman Ananda really saw a big improvement in sound quality. I love the tonality and sound signature of the Anandas, but the problem I've had with them is the bass response and the timbre. The bass showed a remarkable improvement in level and texture. Still short on punch and slam, but great overall improvement. I was going to sell them, but the improvement was good enough to keep them.

I just picked up a Focal Clear from the close out at Headphones.com of the OG Clear. I must admit, I am a bit disappointed in the Clear OG relative to the others on this list. I loved it standalone and they sound great if I don't listen to anything else. But, when I A/B test them against all of the above, they come out last. They are new, so maybe they need to burn in. I decided to get a Utopia to replace the Clears in my full sized headphone line up.

All and all, I love the Hugo 2 + C9 pairing for full sized headphones. I think this is not an obvious set up that can be on anyone's list as their permanent desktop system for a TOTL system. You can get a full sized desk top set up, but with the Hugo 2 + C9, you have both a transportable and a desktop all in one.

Edited to note: The C9 does a really good job at accentuating what a given set of headphones is good at. When listening to all 4 of these headphones, they all sound distinctly different. You need to spend time listening to a lot of music to determine which version of the music you prefer. To me, it's like having 4 favorite restaurants that I can sample any time I feel the urge for that specific flavor.

Now that I am home, I am able to mix and match my gear to see what happens. I had such good luck with Hugo 2 + C9 via USB set up to my laptop that I just had to try it with my Bluesound Node 2i streamer. As expected, getting rid of USB really raised the level of the Hugo 2 + C9. I connect the Node 2i via optical input. The sound stage increased and the bass response deepened. The sound is more 3D. Punch and slam improves quite a bit. The best part of it is that the Node 2i supports Tidal Connect, so I can control the music with my iPhone either using the BluOS app or the Tidal app directly. I haven't tried it with my 2Go yet. This set up is just so perfect.

As a side exercise, I bought a THX AAA 789 amp to see how well it pairs with my Schiit Bifrost 2 DAC. Wow. This set up rocks and it's a matter of preference which set up is better.

Node 2i + Bifrost 2 + THX AAA 789 vs. Node 2i + Hugo 2 + C9. The full sized desktop solution is way cheaper with a retail price of $549 + $699 + $320 vs $549 + $2495 + $1995 or $1568 vs $5039. The THX solution has far greater power, sound stage and transparency. The C9 solution is warmer and has tube sound. So, depending on your headphones, you may prefer one over the other. For instance, for my Custom LX, the C9 solution is better because I can put it into tube mode and get that really deep sub bass rumble. The THX solution is far better with the Focal Clear headphones. The greater sound stage compensates for the lack of sound stage with these headphones. And, since the Clears are already warm, it doesn't lose much pairing with a more transparent source. I was finally able to make the Clears sound good with the Hugo 2 + C9, but it required significant EQ. On the Hugo 2 + C9, the Clears take on an L-shaped sound signature with overloaded bass and really recessed treble and stage. So, EQing them to Harmon corrected this and the sound great with it

Here are the Parametric settings I used. Notice the significant boost in the treble.

Preamp: -6.3 dB
Filter 1: ON PK Fc 24 Hz Gain 6.1 dB Q 1.03
Filter 2: ON PK Fc 2277 Hz Gain 3.8 dB Q 2.35
Filter 3: ON PK Fc 4658 Hz Gain 7.0 dB Q 1.46
Filter 4: ON PK Fc 9687 Hz Gain 8.8 dB Q 0.54
Filter 5: ON PK Fc 14961 Hz Gain -7.6 dB Q 0.06
Filter 6: ON PK Fc 178 Hz Gain -2.5 dB Q 1.16
Filter 7: ON PK Fc 588 Hz Gain 1.0 dB Q 1.44
Filter 8: ON PK Fc 5373 Hz Gain 1.5 dB Q 5.50
Filter 9: ON PK Fc 6010 Hz Gain -2.3 dB Q 3.77
Filter 10: ON PK Fc 6832 Hz Gain 2.1 dB Q 5.80

Fortunately, this is not required with the THX solution.

After initial testing, I am concluding that for full sized headphones, the C9 can sufficiently drive them and make them sound good, but a true desktop solution provides the better overall performance both absolutely and from a price-performance point of view. I think the best use case for the C9 is transportable solution for mainly IEMs and some headphones. But, to drive full sized headphones, full desktop solution is the way to go. The full desktop solution is likely to blow away the C9 solution when I add a full sized tube amp like a ZMF Pendant SE. And, at a retail price of $1995, it will still be significantly cheaper than the transportable C9 solution. There is a significant cost of portability. Your use cases will determine if the price difference is worth it to you.

Thanks you so much for sharing your C9 journey with us, this is very helpful.

Your sharing reminded me of the earlier day when we announced C9 but the product is not available yet. I had stated that in several occasions that C9 will not be able to compete against desktop amplifier at the same price. For some difficult headphones (for example, HE6 or HD800), even our iHA-6 can outperform C9. So unless portability is your primary consideration, desktop system is still an irreplaceable alternative.

Having said that, I am surprised that Focal Clear is the one that become the centre of attention in this discussion. I would have thought HD 800S and ZMF VC are the headphones that demonstrated the limitation of C9. If HD800S and VC sounds good in your setup but not Focal Clear, that probably means synergy is the issue rather than limitation of C9. In fact, I have run into similar situation but with a different scenario: Ultrasone Edition 5 sounds better on C9 than our iHA-6 or HA-6A (N6ii+A02 as source), that definitely suggest synergy is a surprise factor and there is no safe way to completely predict that outcome other then checking it out with our own ear.