Schiit (MultiBit) Bifrost

There is no conspiracy. Just as there is not enough space on the board for a discrete I/V.

 

Any of the three Schiit Multibit DACs provide an immersive sense of dimension and depth to the music that must be experienced to appreciate. I would rather listen to a Bifrost MB for my recreational listening than any D-S DAC at any price point. It is that good. Implementation details satisfy curiosity but the Schiit team has made great design choices at each of the price points. BTW, look at my measurements for all three and you will note excellent channel matching, even in the distortions. Attention to design details results in incredible sound immersion.

 

Wait, people like the sound of a non-discrete I/V stage!? Blasphemy! Burn it with fire! /s

 

This speaks to a question I have had since I purchased the MB Bifrost - Are there any D/S DACs out there that provide this "immersive sense of dimension and depth"? It really is a new experience for me, but I haven't heard any high-end D/S stuff.

 

Yes, the Matrix X-sabre is very good in this area

 

So I have a pile of DACs currently in my acoustic lab for various research, a mixture of price points, (quite a bit of it involves other than recreational listening):

Aurilac Vega
Schiit Yggdrasil
Schiit Gungnir MB
Schiit Bifrost MB
Mousai MSD192
Violectric V800
Ross Martin Audio PCM1794A
April Music Eximus DP1
Benchmark DAC1
RME Fireface UC
Focusright Forte
Resonessence Labs Concero HD
Musical Fidelity V90
ODAC

and a number of others I can't remember off the top of my head. Also have had quite a few go through such as PS Audio PerfectWave and others.

So to which one am I listening? Schiit Bifrost MB. Can't stop listening to this. Incredible achievement. Have the same problem with the two other Schiit MB DACs.

 

I am anxious to hear it (Bifrost Multibit) again, when it makes its way to Colorado. And hey, someone else who owns a Ross Martin. Reviewed that little guy way back for HF. Not a bad piece, but would probably get beat by an updated Modi, perhaps???

 

I have a very hard time breaking away once I start listening too.The Multifrost is unlike anything I've heard. My listening experience with it is next level for me for sure. I don't want to ever hear the other 2 Schiit DACs. The buck stops here. I think.

 

Thanks for replying on this point.

My wording was poor if you thought I was implying anything intentional about the lack of information about the analog output. Rather I was pointing out an oversight.

However, it would be interesting to hear more about this - perhaps in a Chapter of the Schiit Happened book?

In other words, there would seem to be a story that starts at the point where Mike successfully comes up with something that actually fits in the Bifrost case..... and then.... as the analog guy, you notice that there is no longer enough space for the Uber Analog discrete DC coupled output.

Then what ? How did you decide on the AD8512 ?

Maybe we are spoiled from the Schiit Happened book, because we know about the train of thought for most of the other decisions.

But there is certainly less information about this than any other aspect of the DACs (we know that they are 16, 18 and 20 bits, we know all sorts of details about the AD DAC chips and why they were chosen, etc).

Thanks!

 

The Ross Martin can hold it's own when connected to a Bel Canto Reflink for USB to SPDIF. However, the MultiFrost provides more dimension for less overall system cost.

 

To expand on the comment about discrete stages:

1. The discrete stage in the Yggdrasil and GMB are both just buffers. The DACs used there have voltage output. So, they are very simple stages, just four active devices per channel. However, as measurements clearly show, this simplicity does not compromise distortion performance (this is usually the penalty paid...simple discrete amps typically have high THD.) That's why when you see some "2-PPM wonder amp" it usually has about 80 active devices per channel. We can argue till the cows come home which sounds better.

2. The discrete stage in the standard Bifrost and Gungnir is actually a small amp stage—not exactly a discrete op-amp, due to its very specific gain structure and open-loop bandwidth beyond the audio band--but it also takes a voltage output of the DAC, amplifies it a bit, and passes it on. No I/V necessary.

3. Bifrost Multibit is totally different. Its DAC has current output, so it doesn't just need a buffer--it needs an actual I/V stage, or current-to-voltage converter stage. There are many ways to do this, from op-amps to discrete. If you're going discrete, it's best not to use a typical voltage-in amp topology, but to design specifically for current input (into, say, the emitters, with overall feedback to bring the input impedance down--you want very LOW input impedance in an I/V stage, unlike a voltage amp.) However, Bifrost Multibit doesn't have a lot of real estate on the analog board, so we had to choose: discrete I/V OR burrito filter. Both wouldn't fit. I believe Mike and Dave made the best choice, which was to retain the burrito and lose the discrete I/V.

Consider this: the discrete I/V I did for Theta's Gen V had 250-ish through-hole parts...on a 4 x 6" teflon board...per balanced channel. The complete Bifrost analog output stage--which includes digital filter, DAC, glue logic, local power supplies, voltage references, and the I/V stage is 4 x 5". Surface mount gets us only so far.

Aaaannd...there will be a chapter on this.

 

[Removed by Luckbad]

 

I am really intrigued by this DAC. I would love to compare it to USB Monica which is based on the TDA1545, one of the "ancient, NRND or "pull" NOS 16-bit Philips DACs from the Jurassic Age of digital". I am not complaining about this description either. I am fine with the ancient cred. She is a very musical DAC.

I am guessing that it would be an interesting comparison indeed. However, even if the MB Bifrost won, and it might, I would be throwing money at an interim solution, i.e. an indulgence. I should wait until I can justify the outlay for Yggdrasil and recabling my HD800 for balanced.

So intrigued though... $600 plus shipping...

 

My Bifrost Multibit is on its way. Just wonder does Wyrd improve Bifrost Multibit by any chance?

 

More like Yumbo. Or Yambalaya!

 

Does this imply you prefer the Bifrost MB over the Gungnir D/S?

 

I was reading along fine until I got to this.

I stopped and couldn't stop scratching my head. Current output?? All the strings dacs that I looked at till now only have V output due to interpolation amplifier. This to me is limiting in the the absolute theoretical sense. Read a little about string dacs and now it makes sense. To many resistors for designs over 12bits you couldn't fit the design on a chip. Still I cant help thinking about that current output. How the hell did they make a 16bit string dac finally glanced at the white papers of the ad5547z.

2 16BIT RESISTOR LADDERS!!!

Holy schitt. Not only is the data imputted in parallel but the data conversion is done in parallel AND the output is native. No timing errors or over softning of signal due to feedback choices by Chip designer when implementing the tiny amp, you have a schiit load of control, get the timing mechanism down right and stop any bandwidth limiting that delays data imput into the chip and you got a winner. Which makes wonder why not use this chip in the flagship where you could do a discrete I/V and better power supply.*


*I still think that the cause of the "warmth" that some people attribute to this design is due to the limiting power supply.

 

As others have stated, you would need to purchase the USB 2.0 upgrade separately. I would recommend going to USB 2.0. Optical is limited to 24/96kHz, with the Schiit Upgrade to the USB 2.0 you can get 32/192kHz. I am not saying you would need it, but it is extremely useful to me as a recording artist to record masters at those high bit-rates. I was using optical with My Bifrost Uber (without any USB input) when I first purchased my Bifrost. The upgrade to the USB 2.0 was very much worth it to me. Now, on normal audio tracks you may not notice much of a difference - guess it depends if you're listening to anything that is 32/192kHz. Optical is fine for anything 24/96KHz and below - but IMO, the USB gen 2 upgrade is worth it, and I think Schiit has a very reasonable price on it. Extremely easy to install as no firmware upgrades are required, however you should have some experience with electronics if you were to do the upgrade yourself. Schiit does offer the service to upgrade your Bifrost to USB 2.0 as well for an extra fee, but at least you can be confident that they will do it correctly if you are not good with electronics.

The Multi-bit upgrade from a regular Bifrost or Uberfrost, must be sent in because it needs a Firmaware update and other procedures that require Schiit themselves to perform the upgrade.

Quote from Schiit's Website:

"For this upgrade, your Bifrost needs to have its motherboard firmware updated by us, or by an authorized service center such as Electromod in the UK. This requires a specific programming device with an RJ12 connector, as well as software. Because of this, there is no self-install option, sorry."

*Please note this does NOT include the USB Gen 2 input, so if you don't have USB input, and want USB input, you'll need to order both upgrades.

***Please note, I am not an expert in audio or Schiit products, I just use them and love them- just posting my personal experience from optical to the USB Gen 2 input upgrade.***

 

I only listen to redbook or worse, so optical is fine for me now I think. At first I was worrying that not using usb 2.0 would mess with schiit's super mega awesome amazeballs ohmgonnacome filter, but then I later realized that the signal enters the bifrost from computer to dac through the optical, and goes to your headphones as filtered through copper, so it doesn't matter.

 

@schiit I was curious about the way the Bifrost is built (I cannot comment on other schiit DACs or gear because I have not seen the insides of them). But my main question is, is there some kind of advantage to have the mainboard suspended in the air in the middle of the Bifrost and the mainboard connected to the backplate thus suspending the mainboard in the air instead of attaching the mainboard directly to the chassis like say that of a mainboard (motherboard) of a PC?

I just find it curious that it is constructed in this way. Is there some type of advantage to suspending the mainboard in mid air like that or is it simply the easiest way to build the Bifrost (and perhaps other Schiit products)? I would think it would be easier to work on the mainboard or add/remove components or upgrades without having to take the mainboard completely out. This is just out of curiosity and to try to learn something.

Please see pics