We have a lot of USB tweaks last year and I expect there’ll be more introduced in this growing market as magical devices that can solve mysterious audiophile riddles. Today I’m going to explain the technologies often used behind USB tweaks.



Passive filter

Passive filter is filtering device consists of passive components that doesn’t require external power source. There’re two kinds of passive filters, series and parallel.

Series passive filter will interact with electricity on signal data directly. The signal data will run through passive filter before it goes to output.

Parallel passive filter will interact with electricity surrounding signal data. The signal data goes to output without interacting with passive filter directly.

Series passive filter is suitable for problems related to signal data itself such as DC filter, current limit filter, heavy polluted signal data filter, etc. Parallel passive filter is suitable for problems surrounding signal data such as power conditioning filter, harmonic filter, ground filter, etc.



Reclocking

Reclocking is a technique of rounding incoming data to match with generated clock signal from a new source. Reclocking will greatly reduce random jitter because data is aligned with new clock source.

There’re asynchronous reclocking and synchronous reclocking technique. Asynchronous is faster,support higher frequencies and synchronous can reduce jitter more effectively.

However, its side effect with rounding jitter is great too. When incoming jitter isn’t match with the designed level, the rounding error will create a different kind of jitter, periodic jitter that isn’t just ordinary digital noise but can cause tone shift to digital domain.

So reclocking is often recommended for budget entry level sources that don’t use high precision clock causing high jitter level.



Regenerator

Regenerator (or actually, Repeater) will receive incoming signal and regenerate the signal again. It’s often used to strengthen the signal or correcting some problems from original source.

The advantage of regeneration is to correct the errors from original signal like poor sine wave shape, unreliable signal strength, etc. However, it comes with a price of lessen bandwidth and increase latency from repeating the signal process.

There’s other good things that you can implement with regenerator such as supplying cleaner power to regulate signal data, improve the implementations with better clock generator, higher quality parts, improving design, etc.



Galvanic isolation

Galvanic isolation is one of popular isolation techniques. It’s cheaper and easier to implement than isolation transformer. The concept of galvanic isolation is to separate the current flow between circuits from direct conduction.

When one’s circuit is heavy polluted, implementing the galvanic isolation will reduce the interference from polluted circuit. It also is often recommended for safety measures so people often mistake this as ground isolator too.

However, its disadvantage of isolation is great too. It reduces electronic conductivity efficiency because there’s no direct conduction. The changes in electronic characteristics and specifications need to be checked and maintained accordingly.



That’s all about technologies behind popular USB tweaks today. These technologies can solve some of your system problems if you know what your system needs if used correctly.

However, they all aren’t solutions to fix problems at roots. It’s more like trying to minimize the effects of incorrect implementations not fixing the implementation itself. Using product on system without suitable problems to solve may only collect its side effects.

If you ever feel like you’re missing out dynamics and punching of music, you may consider taking out installed tweaks and re-evaluate your system again to solve system’s problems correctly. Happy listening.

Source: http://www.fidelizer-audio.com/technologies-behind-usb-tweaks-explained/