Fyi, I gave in and preordered it. Hopefully I will receive it before the end of September.
I may, but that will be to go with DMP-Z1, not the N8 LoL! I love Sony, and the fact that I sold WM1Z for Dx200 to drive my HD800 was very crazy. The Dx200Ti playing Native DSD512 is also another crazy thing. If anything, I will just keep it for a portable that can play DSD512, not even DMP-Z1 can do DSD512
Thanks mate WOW how thoroughDigital Interface of Cayin N8
The circuit designed of digital interface is not as complicated as the headphone output in N8. The DSD/PCM Digital Signal Processing (DSP) is basically executed by our own FPGA instructions. All the processing digital audio bit stream will feed to the two AK4497EQ chipset for further audio processing, and the digital output will branch off from here directly.
N8 offers 3 digital output and one digital input: it is our first DAP equipped with I2S output, it has our signature S/PDIF (Coaxial) through Typce-C socket, and it can function as USB DAC (input) or USB Transport (output) through its Type-C USB interface.
I2S Digital output (via mini HDMI)
Since we introduced I2S into our iDAP-6 Digital Transport, we sincerely appreciate the technical advantage of this digital interface, that's why we have implemented this in our newly announced reference digital product CS-100DAC and N8 DAP. I2S connection has embedded the clock signal in the interface, this will reduce the jitter of the Transport + DAC combo significantly. That’s why I2S is commonly acknowledged as the most preferred single-wired digital interface both in terms of digital capability and audio performance.
If you are using a DAC with compatible I2S input, this is definitely the preferred digital interface to connect the N8 with our home audio system.
The down side of I2S digital output is not a well-defined standard as outboard digital interface. There are several implementations of I2S for Digital Transport and DAC, back in the 90s Audio Alchemy wrote the history by using 4pin DIN for outboard I2S (I still kept my beloved Audio Alchemy DDEv3.0 till now), and we have several brands using HDMI or RJ45 as I2S connections right now. There is hardly any formal coordination among different approaches so compatibility is a big issue with I2S implementation.
Among the available options, PS Audio is by far the most influential player in the market. Cayin, being a late comer to I2S, decided to use the “pick a boss” strategy and adopted the PS Audio pin-definition on I2S implementation with HDMI connectors. Unfortunately, the compatibility problem is far more complicate then using the same connectors and adopting the same pin definition, it also involve complicated digital audio processing such as handling of interrupt, mute control etc. While we have tested our I2S implementation with PS Audio DAC to ensure reliable playback of both PCM and DSD files, we cannot guarantee N8 will be compatible with all DAC that claim to support PS Audio "style" I2S, we simply don’t have the resource to test them all. We were told by our iDAP-6 users that our I2S implementation works well with the complete line of Denafrips DACs but no luck when paired with Audio-GD DAC.
Since the standard HDMI connectors are far too big for portable DAP, we adopt mini HDMI connector for I2S implementation with N8. To connect N8 to external DAC such as our CS-100DAC, you need a Mini-HDMI to HDMI cable or a HDMI to Mini-HDMI adapter and then connect to DAC with a standard HDMI cable. These cable or adapters are readily available in the market but we advise you to use a short HDMI cable (1m or below) whenever possible.
Coaxial Digital output (embedded in Type-C connector)
Cayin developed a very unique method to implement Coaxial digital output in our DAP back in 2016, when we announce our first Android based DAP i5. We have embedded the S/PDIF bitstream into Type C connector. I understand this proprietary implementation has caused some confusion, so let’s take a look into the methodology.
This is the standard pin-out diagram of Type-C connector.
The pin A8 and B8 are NOT USED for in USB transmission, so they are not occupied in normal application and left out in normal USB-C cable. Cayin used this pin to transmit S/PDIF signal. This is a direct output from the DSP engine, not a DDC (Digital-to-Digital conversion) output form USB Audio.
To get the S/PDIF out of N8, you need a custom make Type-C cable by wiring the A8 and B8 pin to a coaxial cable. Cayin has bundled two two Type-C to Coaxial adapter cable for different applications. The TypeC to 3.5 short coaxial cable connects N8 to portable DAC/amp with 3.5mm TS mono coaxial input, typical examples are such as Mojo and Hugo2. The TypeC to RCA(F) adapter, when used with a standard RCA S/PDIF coaxial cable, enables you to connect the N8 to a desktop DAC and using the N8 as digital source.
Cayin has also developed a CS-30TCR coaxial cable which is equivalent to the TypeC to RCA(F) adapter with a standard RCA S/PDIF coaxial cable. So if you want to minimize the use of adapter in your system, you can go for one of this full-length Type C coaxial cable.
N8 supports DoP and D2P mode over coaxial, so you can listen to your DSD tracks via the coaxial connection if you connect the N8 to a DoP ready DAC with coaxial input. These cables are plug and play, you don't need to do anything about it on the N8 to get it work. It is very convenient and a lot of users claimed to prefer the Coaxial sound signature over USB, so the choice is all yours. Last but not least, please be reminded that off-the-shelf Type-C cable will not compatible with this design and our Type-C coaxial cable will not compatible with standard Type-C devices such as Android mobile phones or tablets.
USB Audio
Othen then the old school coaxial connection, N8 also support both USB Audio Out (USB Transport) and USB Audio In (USB-DAC) from the Type-C USB connector. .
The USB Audio output is, from functional point of view, similar to the coaxial output. I personally prefer the simplicity of coaxial cable and is skeptical with USB Audio implementation because USB cable and connectors buddle power supply alongside the digital bitstream data transmission. A decent USB cable with good internal insulation and high quality connectors will probably solve the problems. The USB Audio option offers noticeably better specification so if you need DSD256 or 32Bit PCM, you'll have to go for the USB Audio option instead of Coaxial.
For USB Audio input, N8 supports Windows (drivers might be required), Linux and iOS system. Theoretically you can connect your iPhone to N8 but you'll need a camera connection kit otherwise you won't be able to extract the digital bitstream out of the mobile phone. N8 only has "limited" support to Android device. Android is a big family and not all mobile phone manufacturers perceive the Android connectivity (esp. OTG implementation) at the same page. So we have encountered some Android devices that is not fully compatible with N8, that's why we didn't list Android as supported device on USB Audio input.
There is one thing we need to warn users in advance: N8 might exhibit delays and/or cannot synchronize with the video signal when function as USB DAC. This will affect the user experience when lip-syn (movie, MTV) or special sound effect (computer game) is an important feature. This is because N8 operates in Asynchronized USB transmission. Back in the 90s and 2000s when digital audio was blooming, IEE1394 Firewire was considered the only acceptable option to connect a computer device to an high end audio, USB was not an acceptable option as those were the time when USB connection was operated in synchronized mode and the extremely high jitter and occasional drop out is a red flag to audiophiles. The Asynchronized USB transmission has solved these inherited problem and gradually replaced the IEEE1394 Firewire connection in high-end audio since 2011, it become the necessary (but not sufficient) criteria to use USB for high quality audio application.
I shall quote the following explanation on asynchronous USB for discussion purpose:
So there are two major issues in Asynchronous USB:
If you must achieve audio and video synchronization, you can do that by adding a delay in the video reproduction. Most Home Theater system will have to handle similar issues and they call it lip-sync, this can be a DSP feature in the Audio-Visual Control Center (Receiver) or a video delay adjustment in the LCD TV or projector, so please check your computer monitor to see if similar feature is in place.
- the DAC’s master clock isn’t synchronized directly to the clock of the digital source (a computer in most of the cases). This controls the datastream from the computer to a buffer near the DA converter. In other word, the audio signal processing is deliberately "disconnected" from the computer clock but the video display remains connected to the computer clock, so the video and audio are not synchronized by nature.
- we need to create a data buffer in the audio circuit in order to hold the audio datastream from the computer, and the buffer will inevitably cause delays in the audio signal with reference to the non-buffered video signal.
Typical desktop DAC use USB-B (make sure you don’t confuse with USB mini-B or USB micro-B) as input connector, so when you connect N8 to desktop DAC, you need a USB-C to USB-B cable. You can also connect N8 to portable DAC/amp but you need to pay attention to the USB input of the DAC/amp. For example, if you connect N8 to Chord Hugo2, you’ll need a USB-C to micro USB cable. You can buy standard off-the-shelf cable for this application conveniently. If you are going to us N8 as USB DAC for your computers, all you need is a standard USB-C to USB-A cable. In fact, the supplied USB-C in N8 package can be used for charging, data transfer and USB DAC already.
Bluetooth
N8 supports BTv4.2, SBC in both receive and transmit and apt-X in transmit only. This will enable the N8 to serve as wireless player and wireless DAC, but since apt-X headphones is still significantly behind the performance of AK4497 DAC, and SBC is not a high quality codec for wireless DAC, the Bluetooth audio features are mainly for convenient purpose only. The important part of implementing half duplex Bluetooth is to enable HiByLink, a feature in HiBy Music Player app that allow you to control the N8 DAP via the Bluetooth connection of your mobile phone.
Regular Bluetooth control app allow you to issue commands such as Play/Pause, Previous/Next from mobile to DAP, at this point the connection is simplex: from mobile to DAP. The HiByLink is a proprietary Bluetooth control implementation and is far more sophisticated. Once connected, your music resources on N8 will be shared with the HiByMusic App by allowing the App to read the file headers and metadata of the N8 local storage. The App on your mobile phone will manipulate the content, and control the N8 operation including creating a playlist. It can even offer user operations that are not originally available on the N8 DAP. In short, the HiByLink is a lossless resource sharing platform based on duplex BT communication.
The following table will summarize the capability of various digital audio interfaces:
Since we are in the subject of digital interface, we might as well cover the file format supported by N8. The following table is self-explained:
Really looking forward to receiving my unit next month.Digital Interface of Cayin N8
The circuit designed of digital interface is not as complicated as the headphone output in N8. The DSD/PCM Digital Signal Processing (DSP) is basically executed by our own FPGA instructions. All the processing digital audio bit stream will feed to the two AK4497EQ chipset for further audio processing, and the digital output will branch off from here directly.
N8 offers 3 digital output and one digital input: it is our first DAP equipped with I2S output, it has our signature S/PDIF (Coaxial) through Typce-C socket, and it can function as USB DAC (input) or USB Transport (output) through its Type-C USB interface.
I2S Digital output (via mini HDMI)
Since we introduced I2S into our iDAP-6 Digital Transport, we sincerely appreciate the technical advantage of this digital interface, that's why we have implemented this in our newly announced reference digital product CS-100DAC and N8 DAP. I2S connection has embedded the clock signal in the interface, this will reduce the jitter of the Transport + DAC combo significantly. That’s why I2S is commonly acknowledged as the most preferred single-wired digital interface both in terms of digital capability and audio performance.
If you are using a DAC with compatible I2S input, this is definitely the preferred digital interface to connect the N8 with our home audio system.
The down side of I2S digital output is not a well-defined standard as outboard digital interface. There are several implementations of I2S for Digital Transport and DAC, back in the 90s Audio Alchemy wrote the history by using 4pin DIN for outboard I2S (I still kept my beloved Audio Alchemy DDEv3.0 till now), and we have several brands using HDMI or RJ45 as I2S connections right now. There is hardly any formal coordination among different approaches so compatibility is a big issue with I2S implementation.
Among the available options, PS Audio is by far the most influential player in the market. Cayin, being a late comer to I2S, decided to use the “pick a boss” strategy and adopted the PS Audio pin-definition on I2S implementation with HDMI connectors. Unfortunately, the compatibility problem is far more complicate then using the same connectors and adopting the same pin definition, it also involve complicated digital audio processing such as handling of interrupt, mute control etc. While we have tested our I2S implementation with PS Audio DAC to ensure reliable playback of both PCM and DSD files, we cannot guarantee N8 will be compatible with all DAC that claim to support PS Audio "style" I2S, we simply don’t have the resource to test them all. We were told by our iDAP-6 users that our I2S implementation works well with the complete line of Denafrips DACs but no luck when paired with Audio-GD DAC.
Since the standard HDMI connectors are far too big for portable DAP, we adopt mini HDMI connector for I2S implementation with N8. To connect N8 to external DAC such as our CS-100DAC, you need a Mini-HDMI to HDMI cable or a HDMI to Mini-HDMI adapter and then connect to DAC with a standard HDMI cable. These cable or adapters are readily available in the market but we advise you to use a short HDMI cable (1m or below) whenever possible.
Coaxial Digital output (embedded in Type-C connector)
Cayin developed a very unique method to implement Coaxial digital output in our DAP back in 2016, when we announce our first Android based DAP i5. We have embedded the S/PDIF bitstream into Type C connector. I understand this proprietary implementation has caused some confusion, so let’s take a look into the methodology.
This is the standard pin-out diagram of Type-C connector.
The pin A8 and B8 are NOT USED for in USB transmission, so they are not occupied in normal application and left out in normal USB-C cable. Cayin used this pin to transmit S/PDIF signal. This is a direct output from the DSP engine, not a DDC (Digital-to-Digital conversion) output form USB Audio.
To get the S/PDIF out of N8, you need a custom make Type-C cable by wiring the A8 and B8 pin to a coaxial cable. Cayin has bundled two two Type-C to Coaxial adapter cable for different applications. The TypeC to 3.5 short coaxial cable connects N8 to portable DAC/amp with 3.5mm TS mono coaxial input, typical examples are such as Mojo and Hugo2. The TypeC to RCA(F) adapter, when used with a standard RCA S/PDIF coaxial cable, enables you to connect the N8 to a desktop DAC and using the N8 as digital source.
Cayin has also developed a CS-30TCR coaxial cable which is equivalent to the TypeC to RCA(F) adapter with a standard RCA S/PDIF coaxial cable. So if you want to minimize the use of adapter in your system, you can go for one of this full-length Type C coaxial cable.
N8 supports DoP and D2P mode over coaxial, so you can listen to your DSD tracks via the coaxial connection if you connect the N8 to a DoP ready DAC with coaxial input. These cables are plug and play, you don't need to do anything about it on the N8 to get it work. It is very convenient and a lot of users claimed to prefer the Coaxial sound signature over USB, so the choice is all yours. Last but not least, please be reminded that off-the-shelf Type-C cable will not compatible with this design and our Type-C coaxial cable will not compatible with standard Type-C devices such as Android mobile phones or tablets.
USB Audio
Othen then the old school coaxial connection, N8 also support both USB Audio Out (USB Transport) and USB Audio In (USB-DAC) from the Type-C USB connector. .
The USB Audio output is, from functional point of view, similar to the coaxial output. I personally prefer the simplicity of coaxial cable and is skeptical with USB Audio implementation because USB cable and connectors buddle power supply alongside the digital bitstream data transmission. A decent USB cable with good internal insulation and high quality connectors will probably solve the problems. The USB Audio option offers noticeably better specification so if you need DSD256 or 32Bit PCM, you'll have to go for the USB Audio option instead of Coaxial.
For USB Audio input, N8 supports Windows (drivers might be required), Linux and iOS system. Theoretically you can connect your iPhone to N8 but you'll need a camera connection kit otherwise you won't be able to extract the digital bitstream out of the mobile phone. N8 only has "limited" support to Android device. Android is a big family and not all mobile phone manufacturers perceive the Android connectivity (esp. OTG implementation) at the same page. So we have encountered some Android devices that is not fully compatible with N8, that's why we didn't list Android as supported device on USB Audio input.
There is one thing we need to warn users in advance: N8 might exhibit delays and/or cannot synchronize with the video signal when function as USB DAC. This will affect the user experience when lip-syn (movie, MTV) or special sound effect (computer game) is an important feature. This is because N8 operates in Asynchronized USB transmission. Back in the 90s and 2000s when digital audio was blooming, IEE1394 Firewire was considered the only acceptable option to connect a computer device to an high end audio, USB was not an acceptable option as those were the time when USB connection was operated in synchronized mode and the extremely high jitter and occasional drop out is a red flag to audiophiles. The Asynchronized USB transmission has solved these inherited problem and gradually replaced the IEEE1394 Firewire connection in high-end audio since 2011, it become the necessary (but not sufficient) criteria to use USB for high quality audio application.
I shall quote the following explanation on asynchronous USB for discussion purpose:
So there are two major issues in Asynchronous USB:
If you must achieve audio and video synchronization, you can do that by adding a delay in the video reproduction. Most Home Theater system will have to handle similar issues and they call it lip-sync, this can be a DSP feature in the Audio-Visual Control Center (Receiver) or a video delay adjustment in the LCD TV or projector, so please check your computer monitor to see if similar feature is in place.
- the DAC’s master clock isn’t synchronized directly to the clock of the digital source (a computer in most of the cases). This controls the datastream from the computer to a buffer near the DA converter. In other word, the audio signal processing is deliberately "disconnected" from the computer clock but the video display remains connected to the computer clock, so the video and audio are not synchronized by nature.
- we need to create a data buffer in the audio circuit in order to hold the audio datastream from the computer, and the buffer will inevitably cause delays in the audio signal with reference to the non-buffered video signal.
Typical desktop DAC use USB-B (make sure you don’t confuse with USB mini-B or USB micro-B) as input connector, so when you connect N8 to desktop DAC, you need a USB-C to USB-B cable. You can also connect N8 to portable DAC/amp but you need to pay attention to the USB input of the DAC/amp. For example, if you connect N8 to Chord Hugo2, you’ll need a USB-C to micro USB cable. You can buy standard off-the-shelf cable for this application conveniently. If you are going to us N8 as USB DAC for your computers, all you need is a standard USB-C to USB-A cable. In fact, the supplied USB-C in N8 package can be used for charging, data transfer and USB DAC already.
Bluetooth
N8 supports BTv4.2, SBC in both receive and transmit and apt-X in transmit only. This will enable the N8 to serve as wireless player and wireless DAC, but since apt-X headphones is still significantly behind the performance of AK4497 DAC, and SBC is not a high quality codec for wireless DAC, the Bluetooth audio features are mainly for convenient purpose only. The important part of implementing half duplex Bluetooth is to enable HiByLink, a feature in HiBy Music Player app that allow you to control the N8 DAP via the Bluetooth connection of your mobile phone.
Regular Bluetooth control app allow you to issue commands such as Play/Pause, Previous/Next from mobile to DAP, at this point the connection is simplex: from mobile to DAP. The HiByLink is a proprietary Bluetooth control implementation and is far more sophisticated. Once connected, your music resources on N8 will be shared with the HiByMusic App by allowing the App to read the file headers and metadata of the N8 local storage. The App on your mobile phone will manipulate the content, and control the N8 operation including creating a playlist. It can even offer user operations that are not originally available on the N8 DAP. In short, the HiByLink is a lossless resource sharing platform based on duplex BT communication.
The following table will summarize the capability of various digital audio interfaces:
Since we are in the subject of digital interface, we might as well cover the file format supported by N8. The following table is self-explained:
