USB-DAC
Retrofittable digital input for the CD player with analog converter TDA1540 or TDA1541. You can switch between CD playback and streaming at the touch of a button. Our USB input makes sought-after hi-fi classics future-proof and retains their value. We have discontinued production of a separate USB DAC.The USB input receives the data securely in asynchronous transmission, which means a gain in quality compared to simple adaptive data transmission. The formerly widespread S/PDIF transmission, whether electrically via an RCA cable or optically via Toslink, is ruled out because of its loss of quality. This module generates its own high-precision clock signal. For both sources, USB and CD, the connection to the analog converter is then unfiltered with the original sampling rate (no oversampling).
Current Android or Apple smartphones, PCs, tablets or notebooks do not require a driver, just like current Windows versions. Linux Zorin or Mint are also tested.
Commercial streamers offer greater convenience, but not better playback quality. With asynchronous data transmission, the quality is determined by the receiver, its two clock signals, and the subsequent analog-to-digital converter. Many models can of course also be connected to our module, but for some models the output must first be set to PCM (DSD over PCM).
A driver can be provided for older Windows versions. The USB Audio Player Pro app is recommended for older Android smartphones.
USB-in module, for TDA1540 14 Bit
USB-in module, for TDA1541 16 Bit
USB-B cable 3m length
USB-B cable 1.5m length
USB-C adapter OTG
The adapter is required for Smartphoness to make it host-compatible. The USB-B cable is then plugged in there.
Installation by us in your CD playerInstallation is free of charge in conjunction with a revision. Please make an appointment before sending in your CD player. If installed by us, USB-B cable and USB-C adapter OTG for smartphones are included.
The quality of digital audio transmission
Discussions about the quality of digital transmissions can occasionally be found on the Internet. On the one hand, digital cables are praised for improving analog playback, while on the other hand, some people generally deny that there are any differences in quality when transmission is digital.To generate a square wave signal for digital transmission, a voltage is switched on and off to produce a digital “0” or a digital “1”. In the example of USB data transmission, the voltage for a logical “0” is 0.0 to 0.3 volts, and for a logical “1” it is 2.8 to 3.6 volts. This margin in the voltages, known as hysteresis, renders voltage losses in the cable or other fluctuations ineffective, enabling reliable transmission. There is no discernible difference between a good standard cable and a high-priced high-end cable of the same length. If there were any deviations, the hysteresis would compensate for them. This is in contrast to analog transmission, where a sine wave signal is generated with a variable voltage. With its continuously changing voltage/amplitude, analog transmission is more susceptible to cable losses or fluctuations.
With error-free digital transmission of the audio signal, there are no differences in quality in the cable. These occur with the conversion to the common I2s standard in the receiver, i.e., before the actual analog converter. This receiver can produce more or less jitter. The differences in quality lie in the type of reception. With adaptive transmission, such as outdated isochronous USB or even older S/PDIF, the data is sent continuously in data packets and the clock rate is taken from the source/transmitter. With asynchronous USB transmission, the relationship between transmitter and receiver is reversed; the receiver determines the data transmission. For this purpose, the receiver uses two separate clock signals: one is communicated to the source for secure data transfer, while the other is used to generate the I2s standard. The difference in quality is due to the lower amount of jitter in asynchronous transmission.
