Firestone BRAVO 24/96 USB transport w/o drivers + reclocker? - Page 29

Very nice: http://soundapproach.com/wireworldultraviolet5squaredusbdigitalatobusbaudio-p-1496.html

Thanks for the link! but shipping to Europe is $99...I'll try to see if a friend could hook me up.

It seems that the real world added value of this cable is about:

-SPC, w/ its good and bad sides(skin effect, grossly overpriced)

-24AWG, even though most manufacturers use a smaller gauge(28AWG) for the power lines in order to minimize interferences

-one sided ground, so the cable shielding ground isn't shared between the 2 sides...possibly a m00t point when using an isolator?

I'm skeptic...but if I can get one for the price of that US site, I'll bite.

I've compared a few cables, the SQ difference between a cheapo 1m and my usual cable(24/28AWG, gold plated, 5ft, ferrite on the device side) is pretty drastic:

Just like they advertize for the WW, the sound is noticeably clearer and less harsh...this cable is a fiver on ebay, made by a big chinese OEM(Hongyan). The markup on the WW is ridiculous..at least when I buy isolators I'm buying a circuit, not some copper wires w/ a fancy purple jacket.

Still, I've read a USB cables comparison(w/ loudspeakers) on a local forum, it seems that the differences were very very small...yet, the WW Starlight was said to sound clearer than the others.

I've given the OLIMEX dongle the faraday treatment w/ several layers of self-adhesive aluminium foil...but I don't think I like how it sounds now, I'll try to A/B several times.

The C@H dongle does support an external PSU but it can't use the USB power, so it's hard to know how much of an improvement a good PSU actually provides. I think I'll order this regulated PSU, as the external 8>15V(3V overheard, so it should be a decent voltage regulator) PSU is optional on the OLIMEX it should be easy to compare. I've been able to source 24VDC LM317T based linear regulated PSU's, but they don't seem to have them in 8>15V

The external PSU goes through the dongle voltage regulator instead of going through the power isolator(75mV ripple spec'ed)...this cannot hurt.

And if anyone has a 1m WireWorld Ultraviolet A/B cable for trade/sale, please PM.

OK, the SQ is definitely better to my ears w/o the aluminium foil around the Olimex..so much for faraday insulation.

BTW, even an unregulated wall wart is far from the 75/150mV ripple of most power isolators: http://tangentsoft.net/elec/psu-tests/

I'm currently using a 14V SMPS wall wart plugged to the Olimex(230V 50Hz around here), the SQ certainly isn't worse. Of course, it goes through the built-in voltage regulator of the dongle...the isolated USB power doesn't(as it's got a min. 3V overhead). This wall wart is plugged onto my computer surge protection thingie, that supposedly lowers EMI/RFI drastically.

The price to pay for power isolation is too high IMHO, besides the Bravo coax output is galvanically isolated anyway. I will run more comparisons to be 100% sure.

I've also A/B/C'ed the aMG/Olimex and no dongle many many times on several HD-sounding tracks, the sound is very noisy w/o any dongle, better w/ the aMG and even better w/ the Olimex. More natural sounding and vocals are even less sibilating.

http://www.circuitsathome.com/mcu/usb/linear-power-supply-on-usb-isolator-board 

Hi, well the IC in the PSU's sold by HQPOWER is this one, and the IC used on the OLIMEX PSU input this one.

We'd need to find a PSU expert to know what he thinks, but these don't seem like top-of-the-range IC's for audio purposes. The only thing I can say is that I've rolled several PSU's and I'm really stunned by how good the OLIMEX dongle sounds, but I haven't tried any premium USB cable for audio either, so I don't know what would gain you the most...a USB3 board w/ external PSU and/or an audiophile USB cable? I plan on getting a WireWorld UltraViolet anytime soon, time will tell.

One thing's for sure, all those external PSU inputs are a good thing, because the USB power is really filthy....even a laptop PSU brick sounds better, especially after the former went through a 75mV ripple power isolator. Ideally you'd want to power a USB3 board from a clean PSU as well, using something like this maybe: http://cgi.ebay.com/5V-9V-12V-DC-Rechargeable-Li-ion-battery-CCTV-cam-/160457580717

We might as well bypass the voltage regulator of the OLIMEX board and tap directly a clean 5V(like this battery thingie) to the USB output of his board..hah!

you'd have to add a switch on the ground of the cable, hopefully it won't be audible.

Yeah, I'm aware of this dongle. It's using LT1085 on the external PSU input...too bad it doesn't have a female jack on its PSU input, just 2 bare wires.

TBH, the Olimex is the cheapest on the market AFAIK, and even when using a 12V laptop brick PSU it still sounds extremely good. You get a rocking USB Isolator for $50 or so. Afterwards, you always have the diminishing returns: using a USB3 board off a 5V battery, getting a snake oil USB cable, using a 12V battery to feed the Olimex...sky's the limit!

I was told by a dongle manufacturer that within 3 months he would be releasing a dongle w/ a linear regulated PSU input, and it'll be compatible w/ the cheap 24V chinese linear regulated LM317-T based PSU's I'm getting(the Olimex can't take >15V) , so I'll hold the upgraditis horses until then. SQ is really fantastic atm, no rush for me