[bflat]

No worries, congratulations!! And with the workaround for now I can still listen. Will be patiently waiting for your ideas/insights/suggestions ..

Are you using the same power supply for your C9 and analog source?The two cannot share the same ground or it will trip the protection circuitry. You can test this by making sure there is no USB cable connected to the C9 while in use.

 

[bukumurah]

IMO it is best to just NOT plug the C9 to any AC outlet while in use because the noise can be quite bad

 

[bflat]

IMO it is best to just NOT plug the C9 to any AC outlet while in use because the noise can be quite bad

That rules out the ground as the problem. If your temporary solution is to keep the button depressed, you run the risk of the protection circuitry not able to protect a "real" problem. I would ask Cayin to give you another battery module to try out.

 

[WDitters]

That rules out the ground as the problem. If your temporary solution is to keep the button depressed, you run the risk of the protection circuitry not able to protect a "real" problem. I would ask Cayin to give you another battery module to try out.

Power Supplies are not the issue here.. In a troubleshooting dialogue the impression that @Andykong had is that somehow the spring mechanism in the in/off button is detective. So my C9 is now scheduled for a roundtrip to China to get sorted.

 

[KOM66]

@Andykong my C9 stopped working tonight.
The on/off button doesn’t light up,
Battery is fully charged. I used it with N7.
It’s about 6 months old. I’ve used it for about 40h. Any suggestions ?

 

[Andykong]

Cayin will debut the following product at the 2023 China Guangzhou International Headphone Expo (16-17 December 2023). I'll be traveling to Guangzhou to check out these new products and we shall provide more information about these new products after the Guangzhou event.

iDAP-8: Android-based Network Streamer
iDAC-8: Dual Timbre DAC/Preamplifier
iHA-8: "Hyper" Class-A Solid-State Headphone Amplifier
HA-2A: Compact Transformer-Coupled Tube Headphone Amplifier

 

[Soundvibrations]

@Andykong my C9 stopped working tonight.
The on/off button doesn’t light up,
Battery is fully charged. I used it with N7.
It’s about 6 months old. I’ve used it for about 40h. Any suggestions ?

Hi, that's unfortunate.. I hope it's not a fault due to a defect in the amplifier..
I was about to pull the trigger on it..but.
If I may, I also have an N7 and only use iems, what does it bring more to the C9 chain? Is there a noticeable improvement? For example in the highs, where I find that the Dap lacks a bit of vertical extension and dynamics, or adds depth which is always welcome.
Is the reason you've used it so few hours in 6 months because you don't like it?

 

[Andykong]

@Andykong my C9 stopped working tonight.
The on/off button doesn’t light up,
Battery is fully charged. I used it with N7.
It’s about 6 months old. I’ve used it for about 40h. Any suggestions ?

We need to find out whether you are having a problem with the on/off control, or you are having some problem with your battery. Have you called your dealer and asked for assistance? They should be able to give you immediate assistance, instead of waiting for me to respond on the forum. I was away to attend a headphone event in Guangzhou last weekend and was unable to respond to any messages until now.

Can you describe the action of the on/off button when you press it? With a fully functional on/off button, when you press the button at the off position, it will stay down and light up the LED. Press it again, and it will bounce up to the off position and the LED will turned off. A faulty on/off button will, in most cases, stay in the off position after you press it down. Alternatively, it will not bounce back to the off position from the ON position and fail to turn on the amplifier.

In case your C9 (or the battery module) entered protection mode, you need to remove everything and connect the C9 or the battery module to a charger, charge it for at least 10 seconds and the device or battery module will revoke from protection mode, and resume normal operation.

Another big possibility is your battery. A regular 18650 battery will charge up to 4.2V. If one of the 18650 batteries fails to hold its charge and drops below 3.0V, which is the cut-off voltage of your 18650 battery, the battery will enter hibernation and your C9 will not be able to function because of a faulty battery. If you have a spare set of 18650 batteries, you can replace the battery to verify if this is a battery problem. You can test the voltage of your 18650 battery with a multimeter, or you can purchase an 18650 tester/charger (look for those that come with a rescue mode). Last but not least, you can send your C9 back to your dealer and ask them to check the amplifier and the batteries if you are not familiar with testing and handling 18650 batteries..

 

[jlemaster1957]

Hi C9 user friends- writing here as a satisfied user for about 2 years with no problems (many thanks to @Andykong along the way- P1 of this thread has lots of links to the rest for troubleshooting —thanks to him!)

Here I am asking a HP pairing issue. I have lately been enjoying my (getting to be vintage) Hiby R8 ->usb-> mojo2-> se-> C9 in pre-amp mode and love every aspect of the chain for almost every IEM and HP- the Mojo allows lots of DSP EQ tomfoolery that allows me to augment eg staging as well as different FR signatures. Anyway I have quite enjoyed the Drop 6XX with the chain and imagine the ZMF Atrium open HP (300 ohm impedance) would work well- earlier users mention the VC works well - has anyone tried the Atrium out of the C9, and if so what mode in terms of NuTubes and Class A v AB did you like best?

 

[KOM66]

We need to find out whether you are having a problem with the on/off control, or you are having some problem with your battery. Have you called your dealer and asked for assistance? They should be able to give you immediate assistance, instead of waiting for me to respond on the forum. I was away to attend a headphone event in Guangzhou last weekend and was unable to respond to any messages until now.

Can you describe the action of the on/off button when you press it? With a fully functional on/off button, when you press the button at the off position, it will stay down and light up the LED. Press it again, and it will bounce up to the off position and the LED will turned off. A faulty on/off button will, in most cases, stay in the off position after you press it down. Alternatively, it will not bounce back to the off position from the ON position and fail to turn on the amplifier.

In case your C9 (or the battery module) entered protection mode, you need to remove everything and connect the C9 or the battery module to a charger, charge it for at least 10 seconds and the device or battery module will revoke from protection mode, and resume normal operation.

Another big possibility is your battery. A regular 18650 battery will charge up to 4.2V. If one of the 18650 batteries fails to hold its charge and drops below 3.0V, which is the cut-off voltage of your 18650 battery, the battery will enter hibernation and your C9 will not be able to function because of a faulty battery. If you have a spare set of 18650 batteries, you can replace the battery to verify if this is a battery problem. You can test the voltage of your 18650 battery with a multimeter, or you can purchase an 18650 tester/charger (look for those that come with a rescue mode). Last but not least, you can send your C9 back to your dealer and ask them to check the amplifier and the batteries if you are not familiar with testing and handling 18650 batteries..

Thanks for your reply. Yes I called MusicTek and they told me to remove the battery module and charge it. That did it. Thanks again.

 

[Pablo67]

Hi C9 user friends- writing here as a satisfied user for about 2 years with no problems (many thanks to @Andykong along the way- P1 of this thread has lots of links to the rest for troubleshooting —thanks to him!)

Here I am asking a HP pairing issue. I have lately been enjoying my (getting to be vintage) Hiby R8 ->usb-> mojo2-> se-> C9 in pre-amp mode and love every aspect of the chain for almost every IEM and HP- the Mojo allows lots of DSP EQ tomfoolery that allows me to augment eg staging as well as different FR signatures. Anyway I have quite enjoyed the Drop 6XX with the chain and imagine the ZMF Atrium open HP (300 ohm impedance) would work well- earlier users mention the VC works well - has anyone tried the Atrium out of the C9, and if so what mode in terms of NuTubes and Class A v AB did you like best?

I would definitely be interested in hearing about the results of the Atrium open as well. As a very recent "C9 Club Member" and a VC Blackwood owner, I can certainly say that the VCs sound really good with the C9. It seems to really bring out the bass in them, which is nice. I'm waiting on a set of AO Cherry to come in...in the next couple weeks (I HOPE!) so we will see. I have been told by many that the AO is NOT amp picky at all...Unlike the VC, which can be a bit "selective" in terms of synergy. All in all, I think the AOs will be fantastic with the C9's power and SQ...(in my best convincing and optimistic voice)

 

[Pablo67]

I am curious about interconnects with the C9...I am awaiting a Plussound x8 series IC (SPC) I have heard amazing things about Plussounds cables & interconnects. I also have heard that their SPC cables are exceptional in SQ. Was simply wondering if anyone has had any experience with the X8 series with the C9...

 

[NJoyzAudio]

I am curious about interconnects with the C9...I am awaiting a Plussound x8 series IC (SPC) I have heard amazing things about Plussounds cables & interconnects. I also have heard that their SPC cables are exceptional in SQ. Was simply wondering if anyone has had any experience with the X8 series with the C9...

Pablo67

Back in Oct 2021 I wrote my own observations/mini shoot out of several IC Cables that I either had made (I had 2 Plussound X8 IC's made), or was able to borrow and posted my thoughts using them on the C9
Here is the link to that test
https://www.head-fi.org/threads/cay...ss-a-ab-portable-headamp.943135/post-16615751

It might be a little long, but it might give you some information that you are looking for
I still use the X8 Hybrid IC I had made of Tri-Silver and PPH from Plussound and still enjoy using it
I still own the PAW 6000 DAP from that test, and it does still get some use, but I primarly use it Cayin N7 I own also
The C9 sound was something I missed when I traveled in airplanes, so that led to a N8ii purchase to get close to the C9 sound. (The N8ii is going up for sale soon, replaced with a N30LE)
I had several AK DAP's but even with the C9 connected to them, just didn't do it for me, and were sold very quickly

You will get a lot of milage from a good IC connected to the C9.
The C9 responded very well to various good quality IC's I've purchased or borrowed. I am always looking to see if I can improve on the sound, but I've so far stuck to my Tri-Silver/PPH combo IC. The X8 Copper/SPC IC from that write up did sell quite a while ago, as it just was not getting a lot of use.
I've borrowed a friends EXO (4 wire) IC and IMO the X8 had a little more soundstage (Width and height) vs the 4 wire if you're wondering.

Here is a picture from that test showing the X8 IC between the PAW6K and the C9, and then going out through another X8 PPH cable to the JH Audio Jolene's I had then
While some of the HW I use now (the IEM's, the cable to the IEM's and the source) are different, the C9 and the IC are still the same.

Hope this information helps and of course YMMV

Good luck finding the sound signature your chasing!

 

[TotallyNotABsName]

Pablo67

Back in Oct 2021 I wrote my own observations/mini shoot out of several IC Cables that I either had made (I had 2 Plussound X8 IC's made), or was able to borrow and posted my thoughts using them on the C9
Here is the link to that test
https://www.head-fi.org/threads/cay...ss-a-ab-portable-headamp.943135/post-16615751

It might be a little long, but it might give you some information that you are looking for
I still use the X8 Hybrid IC I had made of Tri-Silver and PPH from Plussound and still enjoy using it
I still own the PAW 6000 DAP from that test, and it does still get some use, but I primarly use it Cayin N7 I own also
The C9 sound was something I missed when I traveled in airplanes, so that led to a N8ii purchase to get close to the C9 sound. (The N8ii is going up for sale soon, replaced with a N30LE)
I had several AK DAP's but even with the C9 connected to them, just didn't do it for me, and were sold very quickly

You will get a lot of milage from a good IC connected to the C9.
The C9 responded very well to various good quality IC's I've purchased or borrowed. I am always looking to see if I can improve on the sound, but I've so far stuck to my Tri-Silver/PPH combo IC. The X8 Copper/SPC IC from that write up did sell quite a while ago, as it just was not getting a lot of use.
I've borrowed a friends EXO (4 wire) IC and IMO the X8 had a little more soundstage (Width and height) vs the 4 wire if you're wondering.

Here is a picture from that test showing the X8 IC between the PAW6K and the C9, and then going out through another X8 PPH cable to the JH Audio Jolene's I had then
While some of the HW I use now (the IEM's, the cable to the IEM's and the source) are different, the C9 and the IC are still the same.

Hope this information helps and of course YMMV

Good luck finding the sound signature your chasing!

How does the P6K do with the C9? Thinking about getting a C9 for my P6K.

 

[NJoyzAudio]

How does the P6K do with the C9? Thinking about getting a C9 for my P6K.

TotallyNotABSName

As mentioned in the write up from 2021, the P6K does great with the C9.
The Variable LO from the P6K using the "Pre In" setting of the C9 allowed me to control audio from the DAP, and made it much more convenient, and TBH I think it sounded better that way but that is IMO, and YMMV.
Even with the N7 I run it the same way using the Variable Out into the C9 in Pre In mode.

The P6K into the C9 still sounds very good, despite its age, and was better than many other newer DAP's I tried with the C9
Only recently bested by the N30LE into the C9, but right now prefer using the N30LE by itself, so hence keeping the P6K and N7 around for use with the C9 and the N8ii will soon be in the classifieds.
Recently purchased desktop Tube Amp - Resisted that rabbit hole with tube rolling for a few years but succumbed to it this past year, but the C9 will stay around for its versatility and transportability.

Hope this helps.