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

[KickAssChewGum]

Fellow!

I just saw in Cayin’s Wechat group that the official C9 leather case will be available after CNY. The additional battery tray will be available for sale at the same time as well.

Thanks for sharing the info. I will definitely be getting both!

 

[normie610]

Do it! Last night I was listening to my V2 with C9 and doing some comparisons with the Broadway. There are times that I honestly cannot tell the difference. C9 is really that good.

Do not tempt me to the dark side Lord Sidious!

 

[KickAssChewGum]

Haha! I wanted to ask both. I am terrible at editing. Yes, please. I would love to hear about SP2000 or SP1000 connections - the C9 would help me solve the issue of lack of power in all my older DAPs. Excellent but underpowered. Thanks @KickAssChewGum

For the SP2000, I've found the best line out setting is to set it to is '3vSE/6vBAL' in the Line Out settings (Settings > Line Out > Output Options). NB you can set other voltages here too if desired. Make sure you have the latest firmware downloaded.

In the 'Line Out' Settings menu, make sure you have 'Line Out - Activate Line Out button on the Volume Panel' set to on.

Then either connect a 3.5mm interconnect between the SP2000 and the C9 (for either 1.5vSE or 3vSE) or a 4.4mm interconnect between the SP200 and the C9 using EA's AKA adapter (or equivalent) (for either 3vBLA or 6vBAL).

Then set the C9 to Line Input and whichever of the Timbre flavors you prefer. My preferred with the SP2000 and Odin would be AB/Tube but I found the MEST was better on A/Tube for my tastes. Both at Low Gain.

Finally, when starting to play a track, scroll the volume wheel a little and press the on-screen line out button. This will then output the desire line out voltage. (Be careful to keep the C9 volume to minimum until you have made this step to avoid hurting your ears/IEMs). Once the voltage displays on screen at the voltage setting you have chosen, then slowly increase the (very precise) volume control on the C9 until you reach the desired volume.

Please bear in mind that the quality of the interconnect will play a huge part in the sound you get from the combination of DAC/DAP and C9. The stock interconnect is not bad but I found the sound quality increased significantly when I used the Penon Totem 4.4mm interconnect (that is astoundingly good value at only around $80).

I hope that helps!

 

[Kiats]

For the SP2000, I've found the best line out setting is to set it to is '3vSE/6vBAL' in the Line Out settings (Settings > Line Out > Output Options). NB you can set other voltages here too if desired. Make sure you have the latest firmware downloaded.

In the 'Line Out' Settings menu, make sure you have 'Line Out - Activate Line Out button on the Volume Panel' set to on.

Then either connect a 3.5mm interconnect between the SP2000 and the C9 (for either 1.5vSE or 3vSE) or a 4.4mm interconnect between the SP200 and the C9 using EA's AKA adapter (or equivalent) (for either 3vBLA or 6vBAL).

Then set the C9 to Line Input and whichever of the Timbre flavors you prefer. My preferred with the SP2000 and Odin would be AB/Tube but I found the MEST was better on A/Tube for my tastes. Both at Low Gain.

Finally, when starting to play a track, scroll the volume wheel a little and press the on-screen line out button. This will then output the desire line out voltage. (Be careful to keep the C9 volume to minimum until you have made this step to avoid hurting your ears/IEMs). Once the voltage displays on screen at the voltage setting you have chosen, then slowly increase the (very precise) volume control on the C9 until you reach the desired volume.

Please bear in mind that the quality of the interconnect will play a huge part in the sound you get from the combination of DAC/DAP and C9. The stock interconnect is not bad but I found the sound quality increased significantly when I used the Penon Totem 4.4mm interconnect (that is astoundingly good value at only around $80).

I hope that helps!

Thanks so much for the detailed notes!

 

[Whitigir]

Yes, the interconnect is very important, and especially for the C9. Out of all of my experiences with different systems, the higher quality the devices, the more sensitive it is to the interconnect. People can states the opposite otherwise such as “any good and properly designed devices should not be effected by the cables”, and I can tell you for sure that such person had never listened to either a high-end system or cables at all. I can also say the same for people who thought “Oh pure gold is a bad conductor, not as good as copper, less silver”....such person had never listened to ”pure gold” as a materials

 

[Whitigir]

​

PRE-amp vs Line input mode with maximum volume.

When C9 operates in PRE-amp input mode, it is basically functioning as a power amplifier with volume control disable (set to 0dB attenuation) and all amplification circuit operate in full capacity. Theoretically if you use maximum volume in Line input mode and let your DAP control the volume, the signal processing will be the same as PRE-amp input mode, but my personal impression prefers PRE-amp input mode because I get better amplification control, the sound is tight and focused, and the music is more lively. It’s like a water supply system with 5 water taps installed in different location. Theoretically if I turn all water taps to fully open position, the water supply is in its full capacity, but will that be 100% equivalent to water supply when all water taps are removed? Ultimately, this is up to C9 users to experience the difference between the two input modes if you have an appropriate source that offer comparable Line out and Pre-out (e.g, A02, or line out/Pre out of DACs such as Cayin iDAC-6MK2)

So I have been reading up, playing around and come back at this again. IMO, it is clear that C9 can distinct the differences between a Pseudo Line out, or a real buffered true line out. Whether or not the maker would admit to the way they had designed their own DAP and Line Out, the C9 do have the ability to expose the differences between LO sources.

Next up is the Pre-Amp Input. If I am not mistaken, for example, the A02 Pre-amp output is using Analog attenuations VS the C9 which is using 2 stages together. IMO, the C9 2 stages of volume controls is very well implemented and that it permit me to use my in ears IER-Z1R as I have never heard of it before.

However, If taken the Line out into the Line In on C9, the A02 signals will have to go through the 2 stages that involves a digital attenuations VS where as when using A02 Pre-Amp out, there would be only 1 volume attenuation, and that is Analog attenuations by JRC as you stated previously in N6ii thread. So, sticking with the less conversion is the better, I am not surprised that you prefer Pre-Amp out to take advantages of the A02 Attenuations.

I am waiting for A02 to come, and I love how Cayin is paying attentions to the Line and Pre out on A02, together with C9. Theoretically speaking, AK4497-99EQ have digital attenuations by itself. Some makers uses it to simplify the volume control , even on FlagShip players. But here, Cayin does not skimp out on the proper way to control the volume while preserving the integrity of the converted signals! Hats off to you again

 

[eskamobob1]

@Andykong I'm sorry if it was stated before since I can't find it. Are the power output specs of the C9 reported in the first post of this thread continuous power? Or peak power?

 

[xand]

Do it! Last night I was listening to my V2 with C9 and doing some comparisons with the Broadway. There are times that I honestly cannot tell the difference. C9 is really that good.

Actually I would be slightly sad if they're not within spitting distance (at least when both are battery powered) ... Unless of course you notice a huge difference between the Broadway S when battery vs mains powered...

 

[hmscott]

I wish it were as simple as that but unfortunately you just can't compair high impedence headphone with low impedence ones. They need different things (namely high impedence need voltage and low impedence need current). The HE6SE is 50 ohm at 83 db/mw. To be save with enough overhead, you are looking something like 5W @ 50 0hm. The c9 is a fraction of that. Hell, even the most powerful portable is only a fraction of that. The issue here all comes down to current limits. If the cayin rating is continuous power we may actualy be in a good shape, but if its true max powrr like normal I dont think we are even close

Edit: to put this into perspective. While the dt880 600ohm and HE6SE need similar voltage to reach the same SPL, at 120db, the DT880 pulls 22mA while the HE6SE pulls 300mA

See, this is a good example of how "specs" and "math" as applied theoretically don't necessarily match reality.

My Xduoo TA-20 Tube/SS Hybrid Headphone AMP @ 32 ohm put's out 2000mW, and at 50 ohm puts out a bit less power, but the TA-20 drives the HE6SE much better than my Topping A90 that puts out 6.4w @ 32 ohms. The sound from the TA-20 is fuller and more forceful at "rocking out" levels (85 out of 95 on volume dial). Even at normal listening levels (65-75) the TA-20 has more filled out sound stage in comparison to the A90.

We want to listen to the end result, not just measure it. Our ears are the best and most important measuring device as they are the end user of the result of the design effort, to provide human listening enjoyment.

The 600 ohm load and 50 ohm load have different demands to be sure, and are a good real world use case for the C9 as to how it drives those headphones. That's what I use so that is what I need to see tested before I decide to purchase the C9 myself.

Thanks to @bluestorm1992 for his helpful assistance to those of us without a C9 (yet!?), to see if it will meet our needs too.

@Andykong I'm sorry if it was stated before since I can't find it. Are the power output specs of the C9 reported in the first post of this thread continuous power? Or peak power?

Here is what the C9 lists on the Cayin product page:

• Fully balanced, fully discrete, 4-channels high-fidelity headphone amplifier delivers up to 4,100mW (at 16Ω) or 2600mW (at 32Ω) per channel.

 

[hmscott]

I have a hard time fitting the button tops unprotected cells in the tray, and they are 67mm length at Max. Flat top version of protected cells are at least 68.5mm (Have you tried fitting protected cell yet?)
The C9 tray has it own protection circuit built in. So it uses Unprotected battery cells.

The differences between “Protected” and “Unprotected” cells are the Pulse currents. This is the Burst Max current a cell can supply. For example, the ORB-3500, the Pulse current is stated
Max Discharge capability - Pulse Current: 18A (18000mA)
You will get cut off at 10A with “protected version”.
You can find more details here
https://www.fenix-store.com/blog/wh...en-protected-and-unprotected-18650-batteries/

Stock batteries are “unprotected”
US18650VTC6. Because the C9 has it own protection circuits. For a more detailed statements on the protection circuits, I think we need to tag @Andykong here to ask whether the protected circuits on the cells can interfere and pose potential damages to the batteries management circuits on the C9 ? Or how would the Pulse currents effect the system
Using the Search function, you can see his earlier post to stated this

The hardest things about these “Unprotected cells” are the charging and safe storage of them. Always store them in the protective cases and Always use a good charger such as
https://www.orbtronic.com/battery-charger-21700-26650-18650-14500-li-ion-ni-mh-aa-aaa

I don't have a C9 yet, but that is why I get flat top protected batteries when I can as you are right the extra length can be a problem fitting in to some products.

That's what I was wondering, how the protection limits would affect the sound, if at all. I would like to try protected and unprotected cells on the C9 to see how the unprotected vs protected cells current delivery affects the sound.

In general I don't want to use unprotected cells as you say when they find themselves outside of the protected device use, and need to be charged and stored safely

I use that XTAR Dragon VP4 Plus and the Fenix ARE-A4 - it fits the longer 21700 cells that the VP4 Plus doesn't.

If you get a chance to try those unprotected cells in the C9 that would be great, and thank you!

I haven't seen Orbtronic offer the 18650 3600mah cells in an unprotected version...or in a flat top version, here are the physical specs from the Orbtronics website 3600mah 18650 product page: [Back in stock 2/15/2021]

• Diameter (mm): 18.6 mm (+/- 0.03mm)
• Height (mm): 68.9 mm (+/- 0.03mm)
• Weight (g): 47 g

In comparison here are the physical specs for the High Drain 3500mah:

Dimensions:
Flat Top version: 18.5mm x 65.6mm
Button Top version: 18.5mm x 66.6mm

Update: IDK how far the C9 battery bay adjusts to fit cells...@ 67mm max is short of 68.9mm for the 3600mah protected cell length. I'll ask Orbtronic if they can make a 3600mah unprotected for devices like the C9 that do their own internal protection.

@Andykong - what are the C9 battery protections?, I'm hoping not only overcharge protection but also setting an overall discharge limit as well as cell by cell balance to protect the longevity of the cells. Is there also a temp limit on charging / discharging rate?

Update: Email sent to Orbtronic asking about a higher capacity unprotected battery for devices that have their own built in protection. Devices that need high current draw. Please DM me any additional parameters or questions you'd like me to inject next email.

Spoiler: Email sent

Hi!, I've found a product need you currently don't fill. I buy protected cells from you and others to get flashlight protection and charging protection, but a new audiophile product the Cayin C9 has its own internal battery protection for charge / discharge - although I am not fully aware of all those protections provide.

Also, the high drain nature of high power portable audio has been found to benefit from high drain unprotected parameters vs protected - limited current drain - and so Cayin designed their new portable amp to use unprotected cells.

The highest unprotected cell that I've found Orbtronic make is this 3500mah battery:
https://www.orbtronic.com/3500mah-18650-imr-battery-high-drain-rechargeable-orbtronic-li-ion

I use the protected 3600mah model, and I don't see a 3600mah unprotected version with flat top - the Cayin C9 battery tray has a 67mm length limit, here is the protected cell I am referring to:
https://www.orbtronic.com/3600mah-18650-li-ion-orbtronic-panasonic-rechargeable-battery

Would you be interested in providing a 3600mah or higher density 18650 unprotected cell for products like the Cayin C9?

Here are some links from our current discussion on Head-Fi with Cayin representative Andrew Kong (I am hmscott there too):
https://www.head-fi.org/threads/cay...dphone-amplifier.943135/page-78#post-16176883
https://www.head-fi.org/threads/cay...able-headphone-amplifier.943135/post-16177091
https://www.head-fi.org/threads/cay...able-headphone-amplifier.943135/post-16177292
https://www.head-fi.org/threads/cay...able-headphone-amplifier.943135/post-16178322

Here is the Cayin Product page:
https://en.cayin.cn/products_info?itemid=135

Thank you for your consideration of our interest in higher capacity non-protected 18650 cells!, Sincerely Scott

Reply from Sal @ Orbtronic:

Spoiler: Orbtronic email response

Hi Scott,

I see VTC6 3000mAh 30A.
I do not know why 30A is needed but nothing wrong with VTC6.

3600mAh is very rare cell // our protected 3600mAh is probably the last production run for 2021//.
Very limited production run of the core cell. 3500mAh is here to stay - 3600mAh - probably not. Why? 21700 5000mAh + will take over.

3500mAh is the extremely good cell, and I would highly recommend it. Probably the best for your device. Run time winner in medium to low powered devices.
We will stop with the flat top version soon (do not want vapers to use it).
I think that button top unprotected is still within your specs.

But of course, you know better what will work (you can see contact clearance in the battery compartment)

Regards
Sal
ORBTRONIC ®
www.orbtronic.com

So the 3500mah unprotected is the maximum capacity from Orbtronic, and Sal mentions stopping the flat top version and switching to button top (see details in email).

Also the 3600mah protected batch that is now available @ Orbtronic is the last batch for 2021... not for C9 use, but I use it in other equipment.

Sal also mentions the industry moving to the 5000mah 21700 and away from 18650 for devices.

 

[eskamobob1]

See, this is a good example of how "specs" and "math" as applied theoretically don't necessarily match reality.

My Xduoo TA-20 Tube/SS Hybrid Headphone AMP @ 32 ohm put's out 2000mW, and at 50 ohm puts out a bit less power, but the TA-20 drives the HE6SE much better than my Topping A90 that puts out 6.4w @ 32 ohms. The sound from the TA-20 is fuller and more forceful at "rocking out" levels. Even at normal listening levels the TA-20 has more filled out sound stage in comparison to the A90.

How sure are you that you are hearing actually ability to fully run the cans and not at all being swayed by tube tonality? Also, how does the ta-20 do in songs with high dynamic ranges? Lots of stuff will run demanding cans "well enough". Hell, the abyss guys even say you can run dianas on an xcan. That doesnt mean the can is being properly driven though. Something else to keep in mind as well is that desktop gear tends to have less amperage drop off as you run higher volatges for higher impedences. Since the TA20 only lists power at 32ohm and no one (that i can find) has measured continuous power output at a few loads, its possible that the TA20 is also just a bit more capable than the single stat would let on having a more steady current output across its gain range

Ultimately, if you want to try HE6 on the C9, just do it. I am just trying to tell you that high impedence loads and low impedence low senitivity loads dont behaving the same at all

 

[bluestorm1992]

Actually I would be slightly sad if they're not within spitting distance (at least when both are battery powered) ... Unless of course you notice a huge difference between the Broadway S when battery vs mains powered...

I am actually testing against the Broadway balanced version, which is way more powerful than the single-ended version. Broadway balanced is really designed to drive high impedance/low sensitivity headphones, and it is the default pairing of Diana V2/Phi. It even has enough power to drive 1266 quite nicely. That’s why I am a bit surprised that C9 can drive headphones like Diana V2 in a similar way as the Broadway balanced.

 

[hmscott]

How sure are you that you are hearing actually ability to fully run the cans and not at all being swayed by tube tonality? Also, how does the ta-20 do in songs with high dynamic ranges? Lots of stuff will run demanding cans "well enough". Hell, the abyss guys even say you can run dianas on an xcan. That doesnt mean the can is being properly driven though. Something else to keep in mind as well is that desktop gear tends to have less amperage drop off as you run higher volatges for higher impedences. Since the TA20 only lists power at 32ohm and no one (that i can find) has measured continuous power output at a few loads, its possible that the TA20 is also just a bit more capable than the single stat would let on having a more steady current output across its gain range

Ultimately, if you want to try HE6 on the C9, just do it. I am just trying to tell you that high impedence loads and low impedence low senitivity loads dont behaving the same at all

There is no "folding back" of the power or distortion in the sound driving the HE6E V2 from the TA-20 at 80-85 (out of 95) in any music genre I've tried over the last week, with "normal" listening levels at 65-75. The TA-20 has a well designed power supply backing up the Tube/SS power delivery.

The Tube/SS tonality does help a lot, as the SS A90 can sound sterile, thin and wispy in comparison - I'm not enjoying the SS A90 as I used to now that I am comparing the TA-20 Tube/SS sound against it. The A90 still sounds great, but I prefer the "tube" sound of the TA-20.

That is why I am looking at getting the Cayin Tube/SS C9, for a similar sound profile for mobile and portable use.

 

[bluestorm1992]

@Andykong I got you lol! You just liked my post.

Happy lunar new year. You will have a lot to review in this thread now lol. I think there are now 20 new pages from the last time you read.

 

[xand]

I am actually testing against the Broadway balanced version, which is way more powerful than the single-ended version. Broadway balanced is really designed to drive high impedance/low sensitivity headphones, and it is the default pairing of Diana V2/Phi. It even has enough power to drive 1266 quite nicely. That’s why I am a bit surprised that C9 can drive headphones like Diana V2 in a similar way as the Broadway balanced.

Oh yeah, I meant to refer to the balanced version.

If I'm not wrong they can also be powered just with 4 of the same batteries as the C9, so the only "advantage" they have is a larger physical size (which is usually an advantage but hey...)

This is assuming, of course, that you don't hear a big difference between the Broadway depending on whether it's mains connected at the relevant time.

Happy lunar new year @Andykong and all