Bulk Pet

USB transfer technology for for sound quality(Bulk Pet)

Bulk Pet, short for Bulk Pure Enhanced Technology, is the solution that altering the sound quality arising from INTERFACE CO.,LTD.’s original USB transferring technology.
-Bulk Pure Enhanced Technology-

Features

• Not Isochronous Transfers but Bulk Transfers is used in this original USB transferring technology.
• There are 4 types of sound at most, and users can choose anyone they like on the PC screen display.
• Users can enjoy altering the sound quality caused by changing the processing load balance.
• Users can make Bulk Pet coexist with existing USB Audio Class.
• Therefore, they can also use existing Isochronous Transfers to playback music.
• It doesn’t matter which player application you use.
• We provide you the original dedicated USB drivers. (For Windows, Mac)
• The bits of audio data that using Bulk Pet is completely same as ones using Isochronous Transfers.
• Asynchronous Transfers is available.
• Bulk Pet is only for embedded in ITF-USB DSD; A circuit board powered by INTERFACE Co.,LTD.
• Bulk Pet is a registered trademark of INTERFACE Co.,LTD.

Background

In the case of audio playback via USB, Isochronous Transfer is generally adopted.
Audio data is transmitted in a constant period in Isochronous Transfer. On the other hand, processing loading also appears in a constant period.
In Bulk Transfer, transmitting large data and retransmitting when errors occurred is available although it’s difficult to control the timing of data transmission.
We have helped development of USB audio interface using Bulk Transfer to shorten the audio latency.

Then we thought up that using Bulk Transfer to change processing loading for the purpose of improving sound quality.

Some audio equipment manufacturers adopting our product ITF-USB DSD helped us to make adjustments the sounds of Bulk Pet.
In the autumn of 2016, we finally released Bulk Pet.

About Bulk Pet

It is defined to using Isochronous Transfer to transmit the audio data in USB Audio Class.
Audio data is transmitted in a constant period in Isochronous Transfer.
On the other hand, huge proccessing loading also appears in a constant period on host CPU and device CPU.
This huge processing loading causes the sound quality slight changes.

Bulk Pet is the technology that transmitting the audio data in Bulk Transfer.
In Bulk Transfer, it’s able to control the transmission data volume and transmission frequency.

Bulk Pet makes the processing loading of both host CPU and device CPU steady as a result of the transmission data volume’s dispersion reduced.

There are 4 Bulk Pet Modes depending on the balance of the processing loading of host CPU and device CPU.
Users can choose anyone they like.

About Transfer Mode

We introduced 2 types of Host CPU’s processing loading(high or low) and also 2 types of how to transmit the data(Pattern A or Pattern B).

In this way, Bulk Pet has 4 combinations of the sound as follows.

About Layer of Driver software

USB DAC with Bulk Pet can deal with not only Bulk Pet mode but also existing USB Audio Class 2.0.
Therefore, even Host PC which doesn’t correspond Bulk Pet can connect with USB DAC with Bulk Pet by UAC 2.0.
Users can playback music with Bulk Pet in popular APIs such as ASIO, WASAPI and CoreAudio. Also, they can use any music player application with Bulk Pet.

The layer of driver softuware in each OS is below.

Note

• When you turn on USB DAC, it launches in Isochronous Transfer mode.
• When USB DAC connected with the PC which had installed Bulk Pet driver, the previous mode is chosen automatically because PC remembers the previous mode.
• Transfer mode doesn’t change although you disconnect the USB cable.
  If you want to connect USB DAC with PC that non-installed Bulk Pet driver,
  please choose Isochronous Transfer before connecting.