edit: Regarding TOSlink, that wasn't an option he wanted to explore having given up on the Mytek's TOSLink port a long time ago in favor of a Wireworld Platinum Starlight USB and then a Light Harmonic Lightspeed USB cable. The USB just sounds so much better. Speculating: perhaps due to jitter in all the optical<->digital translations?   

Thanks for the info. Highly unlikely the toslink issues are rated so jitter, unless you have a 50' cable. Even then, it's unlikely. People take about a jitter with toslink, but physics tells us the chance of the light bouncing around inside the cable in such a way that would affect the timing is very slim, especially in a short cable. It. Ore likely the resolution was set at different rates for his toslink vs his USB. Even more likely it was placebo effect

toslink does have higher measured jitter than spdif even at 3' or likely even 1'. Whether you want to argue audibility is another thing, but the measured difference is there as a matter of fact.

Er, toslink is S/PDIF, as is 75ohm coax. S/PDIF is a software layer (the protocol, if you will).

BTW, interesting article on jitter from nwavguy
http://nwavguy.blogspot.com/2011/02/jitter-does-it-matter.html

I say SPDIF because it's better than saying RCA. Obviously when I compare toslink to spdif I'm not comparing it to itself so no need to be pedantic when you obviously understand the point being made.

Please don't ever link a nwavloser link to me again. Keep that dougself garbage away from me. Thx a bunch. It's nice for people that can't think for themselves looking for audio jesus or those that lack critical hearing experience.

LOL yeah. All hail our Messiah !

Hi guys, this is my first post, I want to share my thoughts.

1. How come a digital audio signal, which is rarely over 1MB/s (0.8 MB/s for DSD128), can be easily distorted and needs special purifiers in order to secure the integrity, when a USB3 SSD hard drive  which uses 100-200 MB/s can get tons of data without altering it?

2. Im aware that you can get noise from the USB power, and it depends on the design of the dac/amp/usb reciever, but, if you have usb noise chances are you have a bad computer, maybe something old with an oem psu and a low end mobo, there is a huge difference between that and a propper 80+gold psu with a decent brand motherboard, I build computers and I know good components and configuration can make a difference in audio for instance. (maybe a good power regulator if you have mains noise)

3. I think we can test these purifiers by conecting the purifiers out back to the pc and comparing the data.

1. Because you are comparing apples and oranges. USB streaming works over Isochronous mode, which works in real time and has no error correction. Older adaptive mode implementations are also especially bad, because the clock is controlled by the computer, and the CPU isn't particularly interested in the level of output jitter going to your USB DAC.

USB hard drives, printers, thumb drives, etc work in Block mode. The data is sent is sent in packets not in real time, and these packets are error checked and corrected. That's how you can copy your Word document to your thumb drive and get a bit-exact copy, without the need for a USB filter. Keyboards and mice work in a 3rd mode called Bulk Interrupt, and they don't need filters either.

2. USB noise has nothing to do with having a "bad" computer. Any channel motherboard from any brand is not designed for ultra low noise applications when there is no demand for it from 99.9% of buyers. Similarly, even the best 80+ Gold or 80+ Platinum ATX switching power supply creates a substantial amount of noise, as does any switching power supply. It's baked into the cake. Aside from the switching noise itself, the very best ATX power supplies can get down to around 15mV of DC ripple on their 12/5/3.3V outputs. Any decent linear supply can produce closer to 1mV of ripple. NO ATX power supply can get anywhere close to that, and the best linears will be under 1mV.

The amount of DC ripple produced by the ATX power supply on its outputs are also not what you actually end up with on the VBus line from a motherboard output. That will be on the order of 250mV-700mV. A typical laptop running on its power brick will be closer to 1000mV. Compare that to <1mV produced from a 5V linear power supply.