[Tuco1965]

  Chapter 11:
USB Sucks! Or, Mike Joins the 21^st Century
 

1. Worked in the Chilean jungle looking for oil using the first 8-bit A-D converters prior to Theta
2. In 1934, many years before he was born, God appeared to Mike and revealed to him the formula for amazing digital audio, which he has inscribed on 12 lead tablets…

 

I just love the little bits thrown in for humor,  

 

[Makiah S]

 
The Schiit Ass Guard?
 
Believe it or not, we never connected “Asgard” to “Ass Guard” until people started to comment on it after launch. So no, “Schiit Asgard” isn’t an inside joke for “Schiit Ass Guard.” Or maybe the joke’s on us. 

Jason... brother, I'm hoping your planning to make this into a full fledged paper back book... if so I'd like to pre-order 3 copies <3. The humor of it alone will sell! 
 
Still I'm rather glad I got a chance to try the Vali, seeing as I've owned ONE of your awesome pieces of schiit! And for the record... it was much better than anything made in china that was any where near the cost of it!
 
Looking forward to your new balanced Amp and Dac ... but looking forward to the book more ^^ 

 

[davidsh]

If schiit just wasn't that expensive here in EU etc..

 

[judmarc]

Jason, I've been looking forward to this installment, and it did not disappoint. Very informative, as I'd hoped. A couple of thoughts:

- I'm probably confused, but I did not see a description corresponding to my shallow understanding of async USB - that the clock out of the buffer is at the DAC itself. Can you or Mike try to help un-confuse me?

- 384kHz: There are some 352.8 "DXD" audio files around, e.g., at the Norwegian 2L label. The other reason to have the capability of up to 384kHz input is for folks running software interpolation filters offered in players like Audirvana Plus, XXHighEnd, and HQPlayer. (Any thoughts/comments on this from you/Mike?)

Thanks!

 

[jacal01]

 
[snip]  Mike’s original idea for a DAC is what eventually turned into Yggdrasil.

 
What distinguishes the Yggdrasil design then from the subsequent Schiit DAC products?  D/A topology?  Better digital filtering?  Power management?
 
And speaking of USB jitter, any remaining chance of its incorporating a LVDS I2S signal input via HDMI or other?

 

[m2man]

I think the only information we have on the Ygg is that it's the same size as the Rag and it's a DAC. I don't think they've mentioned one detail. Mike might actually like an I2S interface after reading this chapter. My OffRamp would love to play with the Iggy. 10/90 we'll see it.

 

[jacal01]

If so, that'd be half of my wish list.  And since R2R ladder conversion was prevalent back in the day (1934), I'm hopeful there as well.

 

[CJs06]

- I'm probably confused, but I did not see a description corresponding to my shallow understanding of async USB - that the clock out of the buffer is at the DAC itself. Can you or Mike try to help un-confuse me?

Asynchronous

In this mode an external clock is used to clock the data out of the buffer and a feedback stream is setup to tell the host how much data to send.
A control circuit monitors the status of the buffer and tells the host to increase the amount of data if the buffer is getting too empty or to decrease if it’s getting too full. 
Since the readout clock is not dependent on anything going on with the bus, it can be fed directly from a low jitter oscillator, no PLL need apply. 
This mode can be made to be very insensitive to bus jitter.

Courtesy of  http://www.thewelltemperedcomputer.com.

 

[Odin412]

Great post - this story gets more and more interesting! I love the deep-dive into the intricacies around USB. I have to admit that I didn't know the difference between USB 2.0 and USB Audio 2.0 until now. After gaining inspiration from the March meet at the Westin South Coast Plaza (which was excellent) I finally ordered a Valhalla/Bifrost Uber combo. I hope it arrives by this weekend - I can't wait!

 

[mab1376]

  Chapter 11:
USB Sucks! Or, Mike Joins the 21^st Century

 
I'd be curious to see Mike's take on ridiculously expensive USB cables.
 
http://www.amazon.com/WireWorld-Platinum-Starlight-Digital-Audio/dp/B008K47RLS

 

[Butler]

Chapter 9:
Powering Up: Lyr


What products you intend to sell. If you did two headphone amps and then, say, decided to make a deep-fryer, this may not be the best strategy. If you did two headphone amps and then decided to extend the line with another amp or a DAC that works with them, this makes sense.

Tell that to Audio Technica and their sushi maker!

 

[judmarc]

 

Asynchronous

In this mode an external clock is used to clock the data out of the buffer and a feedback stream is setup to tell the host how much data to send.
A control circuit monitors the status of the buffer and tells the host to increase the amount of data if the buffer is getting too empty or to decrease if it’s getting too full. 
Since the readout clock is not dependent on anything going on with the bus, it can be fed directly from a low jitter oscillator, no PLL need apply. 
This mode can be made to be very insensitive to bus jitter.

Courtesy of  http://www.thewelltemperedcomputer.com.

 
Yep, that's what my impression of async USB is.  What I'm confused about is that none of Mike's three descriptions below gave me the picture above:
 

You can recover the clock from the packet clock, barf, or you can have the computer and DAC do some negotiating and guess at the clock, barf, or you can turn the whole car around and drive it from the back seat with the computer providing the clock, barf.

 

[jevans2025]

"But, you know what? If you have a Bifrost, you don’t have to worry. If aliens from the planet Zebtron land on our world tomorrow, bringing physics-defying technology that enables 64/1.544Mbps audio transmission over USB, we’ll have a USB Gen X card soon enough to handle it.

But I wouldn’t hold my breath."

This is one of the biggest reasons that the Bifrost is such a quality product and excellent value. The integrity it takes to make something last instad of planning obsolescence after 18 months is not lost on the consumer.

 

[DaemonSire]

So is it fair to say there won't be a Bifrost 2 then?  Just upgrades to the original Bifrost?
 
I mean, that's the major selling point for it right?

 

[Armaegis]

You could just call it Bifrost 1.2...