Schiit Mimir Mesh and Forkbeard DAC Preview

To be honest, I haven't been keeping up with Schiit lately, so the Mimir surprised me. It's amusing because I remember discussing a "What If" scenario with Jason, similar to those Marvel or DC Comics shows that explore alternate realities, like Evil Superman or Tony Stark as Doctor Doom. My "What If" was this: What if we could attach the megacomboburrito filter directly to the front of the ESS chips during the D to A conversion? I was curious if this was feasible because one aspect I really dislike about the filters provided with the ESS chips is how they stage the sound. The headstage or soundstage often feels flat and lacking depth, which may work for some headphone users, but for me, it feels overly constrained. What was the phrase about the ESS soundstage? As flat as Keira Knightley's chest.

Essentially, the Mimir is a Modius DAC but with two key additions:

1. The Megacomboburrito filter (previously exclusive to the Schiit Multibit DACs), which can also be turned off for NOS mode, and Forkbeard. With Forkbeard, you can use your iPhone as a remote—though it's more than just that!
2. Digital preamp including EQ profiles, such as a three-band parametric EQ.

I integrated the Mimir into my PC surround setup, and I was blown away by the soundstage. There’s now an impressive front-to-back differentiation between voices and instruments! Furthermore, I experienced a level of spatial clarity that I had never encountered before with ESS DACs, which often muddied the presentation and created a flat wall of sound effect in the distance. I can even feel the bass waves propagating toward the listener, although some softness and lack of texture typical of ESS DACs remain. (No, this won’t turn your ESS into an R2R or multibit bass experience.)

What I was most geeked on as the three-band parametric EQ. Seriously three bands is all you need for parametric.*

The thing I am still trying to figure out. How do I change the Q (width of the band - stuck at 4.3) of the PEQ? Going to read manual.

At the end of the day, I must say that the implementation of the custom filter has definitely elevated the performance of this ESS-based DAC. The downside is that, unlike the Modius, the Mimir cannot be powered solely through USB and requires a wall adapter (EDIT: Straight USB works, but plug it in for higher output and betterer sound quality). I will be doing more listening and maybe post a video later.

*The dozen surgical bands of PEQ espoused by the measurement wierdos to make headphones perfectly subjectively neutral or according to Dr. Sean Olive's shitty consumer preference target curve is overkill. Not to mention trying to EQ low bass or high treble to flat when the driver just doesn't want to do it only creates distortion. "Science" is sometimes wrong, or science forgets about something. Keep it simple. Three PEQ bands is enough for 99% of headphones.

 

The Forkbeard features are still in their early stages. I’m still trying to determine how to adjust Q on the PQ—perhaps that functionality isn’t available yet? If that’s the case, the PEQ applications would primarily be limited to addressing treble peaks.

The volume adjustment on the Mimir Forkbeard feels a bit unwieldy, as it requires rapid presses. When holding the up and down arrows, the volume changes very slowly. This design might be intentional to prevent speaker damage. For comparison, the Kara Forkbeard volume control allows for smooth left-right swiping and operates much more easily.

 

See above. If Schiit can get the Mimir Forkbeard volume interface to work like Kara's (below), that would settle it, at least for me. I would prefer it to slide, instead of up and down buttons.

 

I can provide my thoughts on this now. It's challenging to determine which is better in this comparison.

If I'm traveling and can't take my Yggdrasil MIB with me, I'd go for the Modi Multibit 2 (MMB2)—I've actually done this while evaluating the Mjolnir 3 on the go. The MMB2 shares similar sensibilities but is less refined: it has diminished focus, clarity, and resolution.

Overall, the Mimir outperforms the MMB2 as a DAC. I know this might be controversial among multibit DAC enthusiasts, but delta-sigma DACs, particularly those based on ESS chips, tend to be easier and more affordable to get right. However, many audio manufacturers, especially those using older ESS chips, have made them sound bright, stringent, and harsh.

In terms of headstage and soundstage, there’s virtually no difference—both are quite impressive. The Mimir features the "megacomboburrito" filter technology. When I swapped in the Mimir, I thought, “Wow, it’s the Schiit (megacomboburrito filter) sound!” The soundstage was better, more precise, more expansive compared to the MMB1, which I still enjoy for its darker tone and natural timbre.

When it comes to timbre, ESS DACs don't quite hit the mark. While the best implementations of ESS chips manage to achieve good timbre, they often sacrifice it with some softness in presentation. The Modius and Mimir are no exceptions. Furthermore, ESS DACs tend to struggle with bass texture and pitch differentiation compared to R2R DACs.

Even without considering the Forkbeard features, if I were to judge solely on sound quality, I'd likely favor the Mimir over the MMB2, though they are just different. Ultimately, synergy plays a significant role, especially when it comes to unconventional setups such as using XLR to RCA line level transformers, as the balanced outputs often sound better and good transformers can be quite magical. Additionally, the Mimir pairs well, both sound synergy and form-factor with amps like the Pietus.

 

About on par, maybe the Mimir is just a bit less sharp (OS mode) than MMB2 NOS. As I said, very slightly soft (think Weiss, MOTU, Modius, all reviewed here on SBAF), but I'll take this before any ESS design that is ice-picks. The highs transients on MMB2 in NOS are about perfect for me. Providing this info as a reference so you can calibrate to your tastes.

After a bit more listening, again it's interesting. The filter makes the Mimir not 50% but 70% sounding like their ol' multibit DACs because of the filter.

In fact, I'd say the depth is deeper than the BF2/64 from front to back. There is greater distance from vocalists (who are often put on front by sound mixers) than the instruments and backup singers near the back of the soundstage. Maybe it takes a bit of that deep staging inherent to ESS chips and throws the megacomboburrito filter into mix!

Using JBL LS305s for gaming, the Mimir has been fantastic so far with respect to imaging and depth. Clear upgrade from the Modius, MMB1, and built-in Syn DACs. Yes, ESS can pinpoint image!

Headphones may be more a matter of preference because I know some people prefer the always far away placed head stage of ESS (built in filter) over the closer head stage of the Schiit filter. Fair warning; however, I have always been fine with Schiit DACs with headphones. I don't expect headstage to be anything like soundstage (speakers).

Or use an Drop OAE1 headphone for OMFG this stages in front of me effect! (And use Mimir EQ). More on this later.

 

So let’s talk about the Drop Grell OAE1.

I’m not going to sugarcoat this. Axel Grell has created some fantastic gear in the past for Sennheiser, and many of us still use the HD600, HD650, and HD800 in high-end systems. However, he’s also produced some questionable stuff like the HD700. The Drop HD58X doesn’t count because it was really @CEE TEE insisting on flattening the upper mids and extending the bass. (Let’s be honest, Drop went downhill after @CEE TEE left.) I read a review on headphones.com about the OAE1 filled with double-speak about Axel, and I thought, “LOL, make up your mind about the guy.” So here’s my take.

When I first got my hands on the OAE1, I thought: “f**k, I need to turn off the LG monitor speakers in front of me because they sound like shit and are interfering with the headphones.”

Except it wasn’t the LG monitor speakers—I was actually hearing the OAE1!

The OAE1 excels at placing sound right in front of you, thanks to its cavernous cups and the highly angled frontal drivers. It also does a great job of mimicking the poor sound quality of old LG TV speakers or those Bose surround setups from the past, featuring those tiny 2" speakers with a boomy sub.

What I'm getting at is the use case. This is precisely why I’m excited about the Mimir.

 

The OAE1 has a noticeable dip in the mids, accompanied by tinny highs that feature a discernable ssssh sound. The lows are excessively thick, reminiscent of the old Dharma D5000 electret hybrid headphone, which had shitty low-frequency drivers with what sounded like massive third-order distortion (but without the transient response to make up for it). This is how it sounded to me. I don't know how anyone at Drop approved this headphone's frequency response. Personally, I would have fired this person.

Drop OAE1 Measurements

 

PRO TIP: Better to cut than gain with digital PEQ (to avoid overload). I don't believe the EQ auto-normalizes / pushes the gain down.

 

After listening to a few tracks, I opted for broader and deeper cut in the highs and pulled down the lows just a bit. There's the null in the FR, but I don't think it should be EQ'd. It's a just thing with the cavity and shouldn't be corrected. EQ'ing headphones is as much an art as it a measurement. FR measurements should only be a starting point. There is so much more going on, transients, distortion, decay, that needs to be taken into account and trained ears are best for this.

In fact those who suggest EQing purely on measurements should be shot. (And executed like William Wallace in Braveheart). Also people who have never built speakers including measurements and crossover design should disqualify themselves from any measurement talk.

• Band 1: 89Hz Gain -5.5db Q 0.50
• Band 2: 374Hz Gain -3.1db Q 0.80
• Band 3: 6993Hz Gain -7.8 Q 0.98

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Anyway, the QAE1 sounds fricking awesome now with amazeballs front imaging, not like a low-fi Bose surround system, thanks to Mimir.

P.S.

• Clamp is too much on OAE1. Can bend the headband back to make this better.
• Pads are bit uncomfortable, too much force concentrated on small area (think opposite of HD800 where there is a lot of surface area). Maybe Dekoni or ZMF can make replacement pads that don't suck.
• I need one more notch for the cups to do down for best comfort.
• Who da F at Drop approved this again? Asian / Pacific Islanders don't have skinny small Germanic heads.