Schiit DACs (Bifrost and Gungnir down, one to go)? The information and anticipation thread. - Page 59

Thanks a lot, Jason. Good luck with the final hurdles/red tape.

guts:

 

http://schiit.com/cart/images/bifrost_product06.jpg


 

 

ahh that internal shot looks really elegant! now i just have to wait till all the back-order clears before placing my own!

I think that we all know that you can only control the things you do yourself. The trouble with not announcing stuff early is that you will not be able to gauge true demand as easily. It certainly is safer though. That said... Take my deposit on a statement rig now. Please! :-)

This is a risk that I am well prepared to take.

Good luck on a smooth remainder of the Bifrost build process.

Thanks a lot Jason, I can wait for the info on the upcoming stuff, respect your honesty.

But shouldn't a review unit be out there somewhere allready?  I mean some of us would like to read a review before purchasing etc.. 

Exactly!

 

I like the way they dont send out review units for the most part. I know they sent a Lyr to Moon or whoever that was but I dont believe they typically send out review units in advance of actual paying customers, which is how it should be. Do you guys have a quote somewhere from Jason saying he was going to send out a review unit? People keep saying it but I dont remember it ever coming from him. Im asking because I dont know btw.

You'll certainly have that option - though you'll need to wait a bit longer 
 

 

Was just checking out the photo of the Bifrost's internals.  It looks great.  Two comments.  Can anyone see how the USB module clips/locks in?  And secondly are there LEDs on the board?  I am pretty sure that I have asked Jason before and the LEDs offer an electrical benefit and not just a pretty glow.  Does anyone know exactly what they do?

 

I am impressed.  Saves me ever having to open it up to see what is there.

 

Dont know anything about LEDs, but the two piggy-back boards are mounted

with pin-header connectors. You can see the rows of the solder bumps on the boards

above the pins that are projecting downward into the lower pcb female connectors

With the USB jack possibly being plugged and unplugged repeatedly,

it would be bad construction practice to just have the pin connectors supporting the pcb assembly.

There are also (solder plated) screw holes for standoff spacers and through-bolting to the chassis.

These provide the support needed.
 

(he-he if I buy a Bifrost I want to rip it open to see what's under those piggy-backed pcbs. Prolly not much else...)

 

Edited by livewire - 10/4/11 at 4:10pm

Over the last few months while the bifrost has been talked about getting released, i have been adding all the release pictures of anything to do with the bifrost to my background picture file, its nice to see all the pictures of what soon will be in my hands on my desktop background.

LED's offer no electrical benefit. In fact they create noise on the power rails which slightly reduce the sound quality to a minute degree. Not worth worrying about on an entry level product like this.

 

You can see in the internal pic that both the USB board and analog output board are raised above the main PCB. I presume there is a pinout connector on the mainboard they just plug into.

For those who are curious, here's my analysis of the board based on that picture.  I wish I had more time to draw overlays on the picture to point things out.

 

Starting at the right, you can see the IEC plug for the power cord.  It appears to be one with built-in noise filtering.  Behind that is a transformer to take line voltage (110 or 220) down to something the rectifiers and voltage regulators can handle.  I wonder if there is a jumper somewhere to convert this between 110 and 220. I'm not sure if the one black 2-lead component behind the transformer is a diode or not.  If it is and part of the rectifier, it's a pretty high quality rectifier and probably some kind of soft recovery diode, but I'm guessing not for this price point.  You can see a fuse peeking out next to the IEC plug.  The big brown capacitors and the things with the black heatsinks are voltage regulators used to make the voltage for the rest of the device.  There appear to be 4 of them, and that could mean there are 4 different voltages or they are separating out voltages for different functionality:  often the digital stuff has its own power supply in audiophile designs.

 

In the middle is the digital input with the USB board mounted on top of a couple of headers.  There do appear to be 2 red LEDs on the USB board, but I have no idea what they do.  The USB board itself has some kind of controller (probably the USB chip), which is next to the capacitor can with the red strip.  Above it, there's a slight smaller rectangular chip which is either memory or flash storage to keep the programming of the USB controller.  There are also two clocks or crystals near the USB input --- they're the metallic rectangular things that are the same color as the USB port.  They bring to mind how different sampling rate frequencies are handled, but I'm not sure that's what they're there for since they'd have to handle the same issue for S/PDIF.

 

The USB board also appears to have its own voltage regulator, probably to make the voltages needed by the USB controller and other digital stuff on that board.  All voltage regulation everywhere on the device appear to be linears instead of switchings, which makes it generate more heat, but less noise.

 

I imagine that beneath the USB board, there's a lot of stuff going on for the S/PDIF inputs, and perhaps some management of the front panel button and LEDs.

 

Leftmost is the audio board.  I would not be surprised if there is nothing underneath this board.  Anyway, the DAC chip is all the way at the back surrounded by the 8 silver capacitor cans.  The analog output appears to be a discrete design with no IC opamps in sight.  There are 4 transistors per channel, and the passives look to be high quality types --- metal film resistors and good caps in the red packaging.  It's interesting that the audio board has no nearby voltage regulators, as this seemed to be a hallmark of earlier Moffat designs at Theta, but they were probably constrained by the build cost for such an affordable device.  I also wonder if the output is capacitor coupled or they somehow hand trim the DC out of it since there aren't any servos apparent.

 

It appears that the analog outputs travel down 8 pins onto the main board to the RCA jacks.  I find it interesting that there are 8 pins.  Some are surely grounds, but perhaps it's for future expansion for balanced?

 

Hope this was helpful.