Firestone BRAVO 24/96 USB transport w/o drivers + reclocker? - Page 31

leeperry, i've been trying a setup like yours for the last few days - Olimex dongle, Bravo, and a couple of dacs. 

hey, this sounds very sweet, even without upgrading the power supplies.  but the Bravo doesn't handle 88.2khz over USB, so it has its limitations.  

Wanted to throw my two cents in about some issues brought up earlier in the thread:

Lee had mentioned the possibility of changing the USB polling setting. There are some guys over at Computer Audio Asylum who figured out a registry mod to lower the default polling interval of 1ms to 5ms, but I guess that's the highest they could get. Most of them claim a SQ improvement for their USB DAC's. I've done it myself, seems to have made a (possibly placebo, I was doing a bunch of other OS tweaks etc. at the time) difference. Anyway, it involves putting in a new D-WORD value in a bunch of different registry sub-keys that have to do with USB controllers. Here's the thread where they mention how:

http://www.audioasylum.com/cgi/t.mpl?f=pcaudio&m=78994

It isn't clear whether or not you have to add the D-WORD value to every sub-key or just, as the original author states, the keys that also have a "Controller" key. It doesn't hurt to do it to every sub-key, if you're the compulsive type. Also, I use Win7 x64 SP1 and the registry values are still there as described, even though that thread talks about modding for Win XP SP2 only.

Also, Lee had mentioned that he had had no luck in disabling Spread Spectrum on Gigabyte mobos. At least on mine (relatively new one - GA-P55A-UD3 rev 1.0), the Gigabyte BIOS allows you to disable Spread Spectrum if you access the "extra BIOS menu" by pressing Ctrl + F1 and go to I think voltage settings. Anyway, you have to press Ctrl + F1 for the option to pop up, in any case, for disabling.

Also, a question: I guess I'm going to follow the herd and jump for the Olimex dongle over the C@H or the ADuM5000 one. Could someone tell me, though, what chip the Olimex uses, if any? Didn't see on the website any mention of the ADuM4160 or any other chip.

LP, you ever look into the Mapleshade?

You think the Mapleshade is just a re-packaged Hiface? That was my impression when I first saw it as well but I don't know, that's why I brought it up. It does have similar form factor for sure.

Quote:

Originally Posted by grokit 

You think the Mapleshade is just a re-packaged Hiface? That was my impression when I first saw it as well but I don't know, that's why I brought it up. It does have similar form factor for sure.

Yes, it does look very similar to the HiFace.  Perhaps this is one of those OEM deals...M2Tech make them for this company.

There are other examples on that site of modded devices so perhaps they take the HiFaces and mode them and resell them.

I have used the Hiface for quite some time and never had any issues with it with drivers or anything else.

I know quite a few guys that have modded them and swear by the improvements.

You would have to crack one open and see if they use similar internals or what has been modded on this unit.

This is how Bravo works:

Just to clarify: TE7022L can output both I2S and SPDIF. In Bravo, Tenor is outputting SPDIF because Fi-Reclock thing is "made for SPDIF". And, absolutely yes, signal gets through DIR9001. Just by the way, quite a hi-end Furutech Le mans (e.g. see http://www.ultrahighendforum.com/viewtopic.php?f=199&t=1375) is using Fi-Reclock technology, too. And it even has the same TE7022 -> DIR9001 path. Regarding pulse transformers vs. Ferrite beads, this all depends on exact implementation. E.g. so-much-talked-about M2Tech HiFace (which has a sort of the pulse transformer, yet a DIRTY legacy USB power) has effective jitter at around 1000ps. Not that impressive, isn't it? Even stock Bravo has lower jitter indeed (I didn't measure Bravo, but I trust my ears).