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

[loudywen]

The C9 is just an amp. So you need a source to plug into it to get sound out of it. The Hugo 2 is a DAC/Amp combo. So you don’t need an external amp for it to get sound. Most people are happy with only the Hugo 2, but I liked using it in DAC mode an connected to the C9 because I preferred the sound of the Hugo 2/C9 together than directly out of the Hugo 2 itself. I no longer have my Hugo 2. I sold it in favor of a Mojo 2 because I want the EQ features. The sound quality is close, but the Hugo 2 does edge out the Mojo 2 in overall sound quality.

If I want to do this: DAP+Hugo2+C9, which port I should use on Hugo2 to connect to C9? Can I just use a 3.5 to 3.5 cable plug into the 3.5 jack on Hugo2 and the other end of the 3.5 connect to the C9 3.5 input?

 

[bflat]

If I already have Hugo2 should I get C9?

Could you? Sure, C9 is just an amp as others have stated that will give subtle tonal differences to H2.
Should you? Maybe. Just keep in mind C9 can only diminish the resolution and detail out of H2, it cannot improve it.
Who should? If you have a DAP that doesn't have sufficient power for your headphones, then a C9 can solve that. H2 has plenty of power for most headphones.

 

[Slim1970]

If I want to do this: DAP+Hugo2+C9, which port I should use on Hugo2 to connect to C9? Can I just use a 3.5 to 3.5 cable plug into the 3.5 jack on Hugo2 and the other end of the 3.5 connect to the C9 3.5 input?

Yes, 3.5mm out of the Hugo 2 into the 3.5mm input of the C9

 

[jlemaster1957]

The C9 is just an amp. So you need a source to plug into it to get sound out of it. The Hugo 2 is a DAC/Amp combo. So you don’t need an external amp for it to get sound. Most people are happy with only the Hugo 2, but I liked using it in DAC mode an connected to the C9 because I preferred the sound of the Hugo 2/C9 together than directly out of the Hugo 2 itself. I no longer have my Hugo 2. I sold it in favor of a Mojo 2 because I want the EQ features. The sound quality is close, but the Hugo 2 does edge out the Mojo 2 in overall sound quality.

Please see earlier posts in this thread about connecting C9 to powered devices (search for ‘protective mode’ and posts by @Andykong and @Whitigir. The C9 is designed to connect to battery- powered devices. Connecting to a powered device is risky given the ground connections of C9. It may be ok, but you should absolutely NOT charge the C9 while it is this connected and particularly not when plugged into a device with which C9 shares a common ground with your amp - this could be the same power strip. Users have destroyed powered equipment when connecting powered devices and charging C9 from that device eg from a laptop USB-C while connected to the headphone out of the laptop. Your set up is not the same but be very careful. See the first post in this thread for more links, especially post #719

 

[Slim1970]

Please see earlier posts in this thread about connecting C9 to powered devices (search for ‘protective mode’ and posts by @Andykong and @Whitigir. The C9 is designed to connect to battery- powered devices. Connecting to a powered device is risky given the ground connections of C9. It may be ok, but you should absolutely NOT charge the C9 while it is this connected and particularly not when plugged into a device with which C9 shares a common ground with your amp - this could be the same power strip. Users have destroyed powered equipment when connecting powered devices and charging C9 from that device eg from a laptop USB-C while connected to the headphone out of the laptop. Your set up is not the same but be very careful. See the first post in this thread for more links, especially post #719

I didn’t say anything about charging the C9 when playing. I only made comments about using the Hugo 2 with C9 versus using the Hugo 2 alone. Charging and playing the C9 is a no no, but thanks for bring it up again

 

[Andykong]

Please see earlier posts in this thread about connecting C9 to powered devices (search for ‘protective mode’ and posts by @Andykong and @Whitigir. The C9 is designed to connect to battery- powered devices. Connecting to a powered device is risky given the ground connections of C9. It may be ok, but you should absolutely NOT charge the C9 while it is this connected and particularly not when plugged into a device with which C9 shares a common ground with your amp - this could be the same power strip. Users have destroyed powered equipment when connecting powered devices and charging C9 from that device eg from a laptop USB-C while connected to the headphone out of the laptop. Your set up is not the same but be very careful. See the first post in this thread for more links, especially post #719

Playback is not a problem, sharing ground will not cause any issue other than a minor downgrade in the black background which we don't normally spot unless we compare in ABA mode, but we warned our users on charging and listening at the same time if your system involves a desktop source that shares common ground with the C9. This shouldn't be a show stopper though because you can solve the problem by buying an extra C9 batter power supply module and a spare set of 18650 batteries.

On the other hand, the protection mechanism in C9 should halt and disconnect C9 before it causes any damage to your audio equipment upstream. If you are connecting a desktop DAC or preamp output to C9, the moment you plug in a charger to C9, the protection mechanism will kick in and your C9 will stop working. So far we have only received one damage report when the user connects a notebook computer as a source to C9, the notebook grounding system is very different from audio equipment as it is connected to multiple internal "devices" and accessories at the same time, somehow the "1 to many" grounding systems has fooled C9 and failed to trigger the protection mechanism, and tossed the headphone output of the notebook.

 

[111MilesToGo]

I have been reading the Head-Fi thread on the new HiBy RS8 R2R DAP, at least from the point onwards when the first units were shipped. One conclusion is: Cayin, with the C9, you‘ve got quite a trump card in your deck! A long-term one, too.

Just wanted to let everybody know. And also @Andykong, but for sure you are aware of this.

 

[Slim1970]

Playback is not a problem, sharing ground will not cause any issue other than a minor downgrade in the black background which we don't normally spot unless we compare in ABA mode, but we warned our users on charging and listening at the same time if your system involves a desktop source that shares common ground with the C9. This shouldn't be a show stopper though because you can solve the problem by buying an extra C9 batter power supply module and a spare set of 18650 batteries.

On the other hand, the protection mechanism in C9 should halt and disconnect C9 before it causes any damage to your audio equipment upstream. If you are connecting a desktop DAC or preamp output to C9, the moment you plug in a charger to C9, the protection mechanism will kick in and your C9 will stop working. So far we have only received one damage report when the user connects a notebook computer as a source to C9, the notebook grounding system is very different from audio equipment as it is connected to multiple internal "devices" and accessories at the same time, somehow the "1 to many" grounding systems has fooled C9 and failed to trigger the protection mechanism, and tossed the headphone output of the notebook.

Thanks for chiming in Andy!

 

[kajetanjazz]

Will this adapter enable me to connect Hugo 2 to C9 4.4mm input? I have my doubts about shortening anything, but I heard someone uses this method to get better results out of the c9. If it works I’m definitely buying it

 

[Nostoi]

Will this adapter enable me to connect Hugo 2 to C9 4.4mm input? I have my doubts about shortening anything, but I heard someone uses this method to get better results out of the c9. If it works I’m definitely buying it

No, you can't do this. I have this exact same adapter and tried it with both C9 and Mass Kobo. On C9 to Hugo2, you can only go from 3.5mm or RCA to C9. Using an adapter like this and trying to generate a quasi-balanced connection doesn't work - it results in channel imbalance and loss of coherence.

The adapter itself works perfectly when used on the Hugo 2 for balanced headphones, so worth getting for those reasons - but never to connect to an amp.

 

[kajetanjazz]

No, you can't do this. I have this exact same adapter and tried it with both C9 and Mass Kobo. On C9 to Hugo2, you can only go from 3.5mm or RCA to C9. Using an adapter like this and trying to generate a quasi-balanced connection doesn't work - it results in channel imbalance and loss of coherence.

The adapter itself works perfectly when used on the Hugo 2 for balanced headphones, so worth getting for those reasons - but never to connect to an amp.

Thanks! I don’t think I need it cause I already have 6.3mm to female 4.4mm custom adapter from Forza Audioworks. I was sceptical when I read it, but had no experience with the PWaudio one

 

[kajetanjazz]

is there some way to convert to balanced signal? Currawong had a little device which took 3.5mm in and gave 2.5mm balanced out. Sadly it’s not in production anymore

 

[Nostoi]

Thanks! I don’t think I need it cause I already have 6.3mm to female 4.4mm custom adapter from Forza Audioworks. I was sceptical when I read it, but had no experience with the PWaudio one

Also had the Forza one! Will work perfectly. Not really much difference other than I find the PWAudio is better for ergonomics.

 

[Nostoi]

is there some way to convert to balanced signal? Currawong had a little device which took 3.5mm in and gave 2.5mm balanced out. Sadly it’s not in production anymore

I think only some amps can do that - single ended in, balanced out. C9, Phatlab Phantasy II, Mass Kobo 428.....not aware of any little devices tho.

 

[karloil]

is there some way to convert to balanced signal? Currawong had a little device which took 3.5mm in and gave 2.5mm balanced out. Sadly it’s not in production anymore

I know exactly what you mean, I wanted to purchase the same unit before when Balanced was the "in" thing....let me search again what the name of that device is....