Portable amplifier for listening to vinyl records and smartphones
Design and parts used are prone to change without notice.
Many people want to listen to records using their father’s old turntable. Others prefer a second-hand player they’ve bought themselves. Nonetheless, even if the old turntable works, it doesn’t have a headphone output terminal. You need an audio amplifier and speakers to play it. Many people don’t have these at home. Even if you do buy audio equipment, amplifiers in stores now lack a ‘PHONO input’. This makes it difficult to connect to a record player. You will need a record player with a built-in phono pre-amplifier. This is a new product that has recently been released.
Record players are larger than smartphones. If you want to set up an amplifier and speakers, you will need a large space in your room. You will also need to be careful about sound insulation.
We have made the other products besides the turntable small and portable. They can be used in a small space. They also offer sound insulation. We recommend using earphones for listening. The amplifier that connects the turntable and earphones is a portable amplifier that can be charged and used. ‘HAKUshin’ has a built-in pre-amplifier for playing records and a PHONO input. You can connect any old record player.
The humming noise that comes from the turntable. This is known as ground noise. You will not notice it when listening through speakers. But, this noise will stand out when listening to records through headphones or earphones.
‘HAKUshin Vynil’ has a feature that minimizes the ground noise of record players using a virtual ground circuit. It also has a DAC terminal for audio input from smartphones. You can also enjoy music from digital sound source subscriptions with the output turned up.
How HAKUshin Virtual ground noise cancel
works
MM cartridges use a large number of coils and magnets. In contrast, MC cartridges are said to have less noise. They pick up noise from outside on the conductor. It would be better to use an MC cartridge. Still, due to the specifications, you would need to have a step-up transformer. You would also need a head amp, a phono pre-amp, and other equipment. MC cartridges are more expensive than MM cartridges, so they are not kind to your wallet.
Also, when you listen to records using earphones, the machine and the record emit noise. This noise is transmitted directly to your eardrums with the music output signal.
We have included a ‘virtual earth’ mechanism in HAKUshin. This lets you listen to the comfortable sound of records with minimal noise. You can enjoy this even with an MM cartridge using earphones.
There are several ways for eliminating noise.
- Lower the output impedance of the cartridge. The cartridge performs a conversion of the output signal known as ‘HI input, LO output’. Lower the electrical signal resistance at the entrance to the sound to make it difficult for noise to enter.
2. The signal is canceled by using a signal of the opposite phase. This signal should be at the same frequency as the buzzing sound. This is the same mechanism as noise cancellation in earphones.
3. Using ‘virtual ground noise canceling’
We have incorporated a “virtual ground” into the HAKUshin circuit. The virtual ground is created at the midpoint of the power supply voltage. For example, in the case of a single 12V power supply, a “virtual ground” can be created at 6V. This is done using an operational amplifier configured as a voltage divider or buffer.
The ‘virtual ground’ acts as a stable reference point. It is symmetrical with respect to the positive and negative supply voltages. By providing a stable reference point, the ‘virtual ground’ helps to reduce the effects of noise. Ground bounce is a type of noise. It occurs when the ground voltage fluctuates due to a sudden change in the flow of current. This often happens when the state of a digital circuit switches. Common mode noise appears equally on two or more lines with respect to a common reference point. It can be reduced by a stable ‘virtual earth’.
The HAKUshin is equipped with a 384kHz 32bit DAC directly connected to the virtual ground. The S/N ratio has been greatly improved, and you can hear a clarity of sound that you never heard before. A USB OTG cable (sold separately) is required for connection to smartphones and digital players.
We have installed Balance Out in HAKUshin. Please enjoy the sound of the record after noise cancellation with your own cable earphones.
HAKUshin Product Specifications
Equipped with virtual noise cancellation to eliminate the mechanical noise of the record player. S/N ratio 95dB
Equipped with a phono pre-amp. You can connect even older turntables and play them.
2 inputs: AUX stereo input terminals. You can connect not only records, but also smartphones and computers.
2 outputs: 3.5mm stereo terminal, 4.4mm 4-pole balanced terminal, connect to earphones or headphones.
With the MM MC cartridge switch, it can handle all types of record cartridges.
Equipped with a 384kHz 32bit DAC. If you have a USB-C OTG cable (sold separately), you can connect it to your smartphone or DAP. If you can’t recognize the DAC, please use the AUX IN. You can enjoy clear sound with a virtual ground even with an analogue circuit.
Battery charging is possible from the USB-C terminal.
Recommended headphone impedance: 16Ω 32Ω
Maximum output: 18mW
Frequency range: 9-65KHz
Size WHD 58 x 20 x 100mm
Weight: 142g
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