Top Customer Reviews
Dimdim's Blog
"... regarding value-for-money, I think that the Boss DAC claims the priz."
TheArtofSound.net
"The BOSS is like no other imo. It's clean and tuneful signature brings it out to be a more sophisticated little number..."
DiyAudio.com
"We were and are very impressed by the Boss. It is amazing that it is possible to get such beautiful sound for 70 euros!"
RoonLabs.com
"First of all, it has such a deep, deep, low, juicy bass flowing out and projects powerful sound stage!"
RoonLabs.com
"Boss is by far the best Texas Instruments PCM5122 chip based DAC in the market, based on unique technological developments that Allo has put in..."
Plus More >
We all live in a society obsessed by brand names and the latest gadget. Sometimes with reason sometimes with none.
The RPI has one major problem with audio. The clocks coming from CPU can only output one frequency clock perfect (very close), resulting in major problems with audio files sampled at 44Khz (and multiple). Too much jitter on i2s clocks. So we invented the
Kali but there is a second way.
Enter the master mode for i2s. Instead of the RPI giving the clock on the line, the DAC itself sends the clocks and RPI sends the data (file to be played). Since we used 2 clocks the problem above disappears. Ours is not the first master DAC on the market, there are others... read on.
Our BOSS DAC is unique, because of the way we have implemented the design. First we separate the power on 3 channels and filter it: one for the digital side, the second for analog and third for the clocks themselves. Then we take the filtered power and use a second filter (LDOs) to further quiet the noise. Note that we use some of the best LDOs on the market (LT3042 from Linear). In addition, we use Japanese oscillators from NDK for a very low jitter clock - almost as good as famous Crystek.
Finally, on the analog stage we are using a film capacitor (not ceramic) for a quiet DC to feed the TI IC (ceramic exhibit some piezo distortion, not what you want in analog stage). Not happy with this, we have added a supercapacitor for an extra kick when analog stage is asking (like deep bass).
What we have achieved, in our opinion, is the best analog implementation of the PCM5122 on the market, while at same time correcting the clock problem from RPI.
Yes we live in a society obsessed with the latest gadgets. The BOSS however, is a very solid implementation of the PCM IC that will give you the greatest bang for your buck. It will sound great no matter what you throw at it - this was our goal and promise to you.
Features
HAT Size Not HAT Compliant
- For RPi
- BOSS is a Master DAC (Master DACs are compatible only with RPI)
- Compatible with RPI2 and RPI3
- Compatible with OSMC / Max2Play / RuneAudio / Volumio / Moode / PiCorePlayer / PiMusicBox / OpenELEC and others + Roon Ready
- Dedicated 384 kHz/32bit high-quality DAC PCM5122 for best sound quality
- Audio output connectors: 2 x RCA (Left & Right ) & Allo Volt Amp header
- HAT size
- DAC SNR is 112dB
- DAC THD+N @ -1dBFS are –87dB
- Full Scale Output of DAC is 2.1Vrms
- Dynamic Range of DAC is 112dB
- Sampling Frequency ranges from 8 kHz to 384 kHz
- Ultra-low-noise voltage regulators & LPF for optimal audio performance
- Noise level: 66.27uVrms
- Integrated EEPROM for automatic configuration (with write-protection)
- Automatically switching frequencies according to the input I2S signals
- Dual low jitter NDK crystal oscillators for Master Clock generation
- With 45.1584/49.1520 MHz Ultra Low Phase Noise Oscillators
Technical Specifications
BOSS Header PIN-Out Details
|
RPI
|
PIN
|
PIN
|
RPI
|
|
NC
|
1
|
2
|
DC +5V
|
|
SDA1-I2C
|
3
|
4
|
DC +5V
|
|
SCL1-I2C
|
5
|
6
|
GND
|
|
GPIO4
|
7
|
8
|
UART_TX
|
|
GND
|
9
|
10
|
UART_RX
|
|
GPIO17
|
11
|
12
|
I2S_BCLK
|
|
GPIO27
|
13
|
14
|
GND
|
|
GPIO22
|
15
|
16
|
GPIO23
|
|
NC
|
17
|
18
|
GPIO24
|
|
SPI_MOSI
|
19
|
20
|
GND
|
|
SPI_MISO
|
21
|
22
|
GPIO25
|
|
SPI_CLK
|
23
|
24
|
GPIO8
|
|
GND
|
25
|
26
|
GPIO7
|
|
ID_SD
|
27
|
28
|
ID_SC
|
|
GPIO5
|
29
|
30
|
GND
|
|
GPIO6/DMUTE
|
31
|
32
|
GPIO12
|
|
GPIO13
|
33
|
34
|
GND
|
|
I2S_LRCLK
|
35
|
36
|
GPIO16
|
|
GPIO26
|
37
|
38
|
I2S_DIN
|
|
GND
|
39
|
40
|
I2S_DOUT
|
** Highlighted signals are used by BOSS board
|
BOSS J19 PIN OUT DETAILS ( Allo VOLT Header)
|
|
RPI
|
PIN
|
PIN
|
RPI
|
|
5V
|
1
|
2
|
5V
|
|
NC
|
3
|
4
|
NC
|
|
SDA1-I2C
|
5
|
6
|
GPIO4
|
|
SCL1-I2C
|
7
|
8
|
GPIO17
|
|
NC
|
9
|
10
|
GPIO27
|
|
NC
|
11
|
12
|
GPIO24
|
|
GPIO23/ SDZ_AMP
|
13
|
14
|
GPIO22 / MUTE_AMP
|
|
GND
|
15
|
16
|
GND
|
|
BOSS J20 PIN OUT DETAILS (Allo VOLT Header)
|
|
SIGNAL
|
PIN
|
PIN
|
SIGNAL
|
|
GND
|
1
|
2
|
GND
|
|
AUDIO RIGHT
|
3
|
4
|
AUDIO LEFT
|
|
AUDIO RIGHT
|
5
|
6
|
AUDIO LEFT
|
|
GND
|
7
|
8
|
GND
|
| Operating Temperature |
0C to 70C |
|
Board Size
|
LWH = 67.4mm * 65mm * 22.2mm |
|
Board Weight
|
28g |
Support & Downloads
If you planning to buy BOSS DAC, the DAC's out put is RCA ... the amp's RCA in will be wired to BOSS DAC RCA out thats all AMP should support RCA from BOSS DAC
BOSS is a DAC ,if you wanted to play without AMP, you can use RCA to headphone cable and play song via head phone.
AMP your speakers will be wired ...there are two kind of speaker system ,active and passive speakers
Active speakers, on the other hand, have a built-in amplifier and are fed by a low-level (line-level) signal passed along an interconnect cable originating at your preamplifier or controller. Because the amplifier is an active electronic device, it needs power, and so you have to put any active speakers near a power outlet.
BOSS DAC have only RCA as output, but ALLO have a have own AMP solutions (VOLT+ With Stepped Attenuator).
An RCA connector, sometimes called a phono connector or Cinch connector, is a type of electrical connector commonly used to carry audio and video signals. The connectors are also sometimes casually referred to as A/V jacks.
