Schiit Happened: The Story of the World's Most Improbable Start-Up
Dec 16, 2020 at 12:15 PM Post #68,281 of 72,779

Pietro Cozzi Tinin

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Perfect.

I've been traumatized by the BBQ sauce bickering (a well cooked piece of meat requires no sauce). Help please.
I see. We can try to get some drugs approved but the people for that are a bit occupied elsewhere.
Meanwhile keep eating veggie burgers.
 
Dec 16, 2020 at 12:32 PM Post #68,283 of 72,779

Pietro Cozzi Tinin

Headphoneus Supremus
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Delft, The Netherlands
1608139918099.png
 
Dec 16, 2020 at 12:37 PM Post #68,284 of 72,779

valiant66

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I never log in to U-tube and it always works fine for me.

I find that there are videos in the wild that won't play in place and pop up a warning to the effect "this video must be watched on YouTube".

You don't need to be logged in as a user, but their business model means they have to be able to track you so they can monetize you. Thus they want/prefer/need you on their site so they can place/read their cookies and refine the profile they already have of you.

That's why it works for you .
.
 
Dec 16, 2020 at 12:47 PM Post #68,285 of 72,779

CarlosAudio51

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New Schitter here, my Asgard 3 just shipped today. Can't wait to try it with my HD 660S.

How about a Modi Multibit update? Bifrost a bit over my budget.
Get one while you have the chance. Based on Jason's comments on this thread before, it'll probably be discontinued after the AKM supply situation gets figured out. Could be a year, though, so no rush.

Unless of course, they release a successor to the Modi MB that we've all been speculating about since Modi 3 got the Unison upgrade.
 
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Dec 16, 2020 at 1:03 PM Post #68,286 of 72,779

darkarn

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Get one while you have the chance. Based on Jason's comments on this thread before, it'll probably be discontinued after the AKM supply situation gets figured out. Could be a year, though, so no rush.

Unless of course, they release a successor to the Modi MB that we've all been speculating about since Modi 3 got the Unison upgrade.

I wonder if I should send in my Modi Multibit for that upgrade if it happens haha
 
Dec 16, 2020 at 1:08 PM Post #68,287 of 72,779

Delirious Lab

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a product that requires two to do stereo
My bet is on a mono, balanced Loki. The perfect product to name after the trickster god - you've been clamouring for a big boy EQ, your wish is granted! Only, you have to buy two. :smiling_imp:

On another topic...
1608142639929.png

Why oh why are there so many unsold $120 Asgards ? This seems too good to be true.
 
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Dec 16, 2020 at 1:34 PM Post #68,288 of 72,779
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2020 Chapter 16:
The Promised Land?



So now there’s Jotunheim 2.

jotunheim 2 insitu 1920.jpg
Here’s what’s the same as Jotunheim: the bottom chassis, the transformer, and the super-duper Alps RK27114 “Blue Velvet” potentiometer.

Here’s what’s different: Nexus™. Continuity S™. Matched and supermatched parts throughout. A whole new linear power supply, with much lower noise. Higher power output. Lower distortion. Better performance. Switchable preamp outputs.

No, wait, I forgot something else that’s the same: the price.

As in, Jotunheim 2 is still $399.

Sounds crazy? It is, a bit. It’s crazy enough that we’re billing Jotunheim 2 as “the best $2400 amp you can buy for $400.”

Oh wait.

Someone’s pissed now.

Crossed arms. Flaring nostils.

“How can you bill Jotunheim 2 as the equal of a $2400 amp!” you shout. “That’s just marketing hype! Not a fair comparison at all!”

Hmm.

Well, okay. Gotcha. But please have a look at what’s available that is
  1. really truly balanced and differential
  2. really and truly fully discrete
  3. using parts like Alps RK27114 “Blue Velvet” potentiometers
  4. has a 100% internal, 100% linear power supply
  5. has insane attention paid to parts quality, including using 1% front-end matched JFETs and 10% matched BJTs throughout—in the input, voltage gain, and output stages
  6. provides tons of power for hard-to-drive headphones AND is super-quiet for the most sensitive IEMs.
And, you know what? Unless you’re talking megadollar amps, there’s exactly nothing out there.

As in zero. Nada. Zip.

Everything else at Jotunheim 2’s price point is simply another IC-based amp. Nothing wrong with that—we do that in Magnius, at $199—but it isn’t an all-out assault on making the best possible product for your desktop.

Go ahead. See what else is out there. Do the research. Take the time. Come back to us.

And ya gotta admit…Jotunheim 2 is a helluva thing, ain’t it?


The Road To 2

The original Jotunheim was a fundamental re-think of every desktop amp we’d done before. When we introduced it in 2016, it introduced the “modular desktop control center” concept that allows you to choose a module (DAC or phono) to tailor the product to your needs, and to help ensure that you’ll be ready for future changes in DAC technology. The modular idea was so successful we took across the line to Lyr 3 and Asgard 3…and eventually even used the same modules in Ragnarok 2.

For a long time, I thought Jotunheim was really the best we could do in a solid-state amp of that size. But I always play with new ideas, including one that led to the development of our Nexus™ topology.

In fact, Nexus was born in a Jotunheim. Or at least kinda. I mean, it was a very hacked-up Jotunheim layout, with cards stacked on top…

Ergh. Let me back up and talk about prototyping.

Prototyping can be a giant pain in the ass, because when you’re operating at the low noise and distortion levels of Jotunheim or Jotunheim 2, you really should be starting with a PC board layout. Because the layout matters. A lot.

But doing a new layout for each prototype, and stuffing the entire thing, including the power supply, the connectors, the controls, etc is a lot of work. And I had four or five ideas on how to improve the performance of the Pivot Point stage in Jotunheim. Which would mean four or five full layouts (or more, if I wanted to do variations). And then even more if I wanted to tweak a few.

So, being lazy, here’s what I did: I ripped out the entire gain stage of Jotunheim and laid out the board with headers so I could just drop small cards into the power supply and I/O functions. Then I only had to lay out one small board, one channel only, and then drop them into the “sled” to see how they worked.

Yeah. I know. I’m lazy.

And yeah, I know. Some of you want a Jotunheim where you can swap out different kinds of gain stages. Let me make this easy: absolutely not.

Why? Not because we hate you, but because that’s simply too many variations. Too many different Jotunheims to stock. Imagine it: choose one of two DACs, or a phono stage, one of two or three gain stages, one of two colors…Alex would have my head on a pike.

So. No. No gain-stage-modular Jotunheims.

Anyway, back to the story. I had several ideas to try to improve on Pivot Point. The first two offered some interesting variation, in terms of distortion profile and perceived sonics, but the third—the most questionable—surprised the hell out of me. As in, it didn’t display the N/N+1 gain structure I expected of the inverting and noninverting inputs, while still offering high impedance inputs on both side. Which made it that mythical “ideal” differential gain stage I never thought I’d achieve.

Super exciting! But also super problematic. Early Nexus stages had very low VAS gain, and tended to drift off its bias center. It would work good for a while, then as the stage differentially warmed, it would drift off and measure (and sound) like ass.

I tried several ways to fix this, including passive approaches that tried to use the thermal drift of the opposite side to cancel the other, and complex operational-point-servo approaches that used up to three servos to try to keep things in line.

Nothing worked.

Well…except sometimes.

Which made no sense. Why did it work sometimes, but not others? I tried some other layouts, trying to play the thermal and operational points against each other, but again, sometimes they worked, and sometimes they didn’t.

The problem was, I thought, if the devices were perfect they’d never be able to get off center…

But to do that, we’d need tightly matched parts.

And matching parts is insane, or maybe impossible. In the old days at Sumo, we had teams of people matching transistors by hand, painting the tops of the TO-92 devices with a rainbow of fingernail polish to denote their grades…but those were thru-hole parts. SMD? Heck, how would you even start with that?

But then I found entire lines of gain-matched transistor arrays, already done, already SMD, and affordable. Suddenly the whole idea didn’t seem so crazy.

The last frontier were the input JFETs. I contacted our purchasing partners and asked if they could match and re-reel them. The answer was yes!

And suddenly, Nexus worked all the time.

But even then, Nexus wasn’t exactly what I thought appropriate to an affordable amplifier. That’s why it went into big dollar stuff, like Ragnarok 2, to start. A low-current iteration for Freya S just barely worked out.

And then, when it was time for Jotunheim R, Nexus made sense. Jotunheim R would never be inexpensive, with its limited production and heroic design for driving ribbon headphones. So it got Nexus too.

But when it was time to look at Jotunheim 2…hmm.

Actually, I’d been looking at Jotunheim 2 since long before Jotunheim R. And I always wanted to get Nexus into it. But with its cost constraints, it wasn’t super appealing. I knew people wanted switchable preamp outputs, which would take a couple more relays and another switch, which would already increase cost. Going to Nexus would increase cost even more.

And…people also started asking for Continuity™, our constant transconductance stage, in everything, once it showed up in Lyr 3 and Aegir.

But Continuity™, while more efficient than Class A, is still and inefficient stage. Trying to shoehorn that into Jotunheim would require more outputs—and, worse, much higher power dissipation (or much lower power output.)

Still, I had to try.

So I laid out a Jotunheim 2 prototype with the whole schmear: Nexus™ and Continuity™.

It did a little over 1 watt into 32 ohms.

Sigh. Yeah, sorry, guys, I’m not sure the world would accept a successor amp with 1/5 the output of its ancestor. Nope, nope, nope. Not going there.

So I did one without Continuity.

This one did the power output, and it sounded pretty good, but it lost something. Yeah, I know, subjective BS and all, but whatever.

What I really needed was something like Continuity…but more efficient.

Aside: the problem with Continuity is the lower the standing bias, the larger the sense resistors have to be…which means the higher the voltage loss, and thus the lower efficiency. In some amps, like Lyr, Asgard, and Aegir, this works great. But if you’re going for an amp that isn’t a room heater and still has good power output, it’s not the first choice.

And that’s what started a more-than-year-long quest to try to get Continuity’s efficiency up. This comprised many new boards, including some truly wacky things with gain on the sense resistor and super-complex output arrangements. These all either:
  1. Didn’t work
  2. Didn’t improve efficiency
  3. Were unstable and unusable
  4. Sounded like butt
  5. All of the above
I was just about ready to give up and do a Jotunheim 2 with a conventional Class AB output stage (it did sound fine, after some tweaking, but you always wonder what you’re missing, right?) when an alternate idea came to me, one that didn’t use the sense resistor in a way that threw away voltage swing. It wouldn’t be exactly like Continuity, but it would counter the transconductance droop…by acting a bit more like a supercharger that came in only when current needs were highest.

Hence, the Continuity Supercharger, or Continuity S™.

The results? Jotunheim 2 now does 7.2W RMS into 32 ohms at 1% THD, up from 5W on the Jotunheim. (We rate it a bit less at 6W RMS, because that's how we do things around here.)

Holy moly.

And there you have it: Nexus, Continuity S…and preamp output switching, and the same crazy big-ass Alps potentiometer, and still an all-linear supply and modular design, the same steel and aluminum chassis, the same made-in-USA-ness…

For the same price.


But What About…

I personally think Jotunheim 2 is pretty much the best thing we can do at its size and price. And Jotunheim 2, at least the final version with Continuity S, has displaced Lyr 3 and Asgard 3 at home. Yes, even Lyr 3. Lyr 3 is a great amp, and, in the final analysis, might be the right amp for someone else. And Asgard 3 is an insane value, a fun and friendly amp that might be the end game for most sane humans, especially if you don’t want to go down the balanced headphone rabbit-hole.

But Jotunheim 2…it’s really, really special. I personally think “the best $2400 amp you can get for $400” isn’t all hype. Again, compare apples to apples, and factor in the discrete design, the differential topology, the insane parts quality, the obsessive matching…and the list of amps gets pretty short.

But of course there are always opinions, and some of those opinions will center around the discrete nature of Jotunheim 2. Some will ask, “Why discrete when integrated options measure better?”

And yeah, we hear you. Magnius measures better than Jotunheim 2. Magnius is also half the price, so if you want measurements, you can save a ton of money.

But here’s the thing: a lot of people like discrete amps. A lot of people like the more bespoke approach, the lower open loop gain, the freedom to do some interesting topologies that may not be available on any IC (like Nexus). And that’s perfectly fine. Some people like Tesla, some people like Subaru, some people like Ferrari.

We personally think there’s room in our line for an affordable uber-measurement amp, and a more expensive discrete design, which also has some distinguishing features like modularity. As I like to say, we’ll see how it goes.

And some people will note that the single-ended outputs don’t measure as well as the balanced outputs. Yeppers, 100% right. That’s what happens when you use one phase of a balanced output and lose all the distortion cancellation from a differential topology.

Aside: it also gives you a distortion profile that’s reminiscent of a tube amp. Hmmmmmmmmmm….

But is this a bug or a feature? Maybe the single-ended output sounds a bit softer and tubier because of its distortion profile. Or maybe all distortion is sufficiently below the transducer distortion that you can’t hear it at all, in which case the argument is moot. Or maybe most people choosing a differential amp will typically be using it with balanced headphones, and the single-ended output is a convenience.

In any case, this is literally the same approach we took with the original Jotunheim, and the approach we used in Ragnarok, and the approach we used in Magnius, because that’s what our customers said they preferred—using one half of the differential output, rather than summing to single-ended.

And it’s not like we’re hiding the difference in performance. The full APx555 report is downloadable, and it covers both balanced and single-ended output.

So, are we cool?

Yes? Great.

No? Well, here’s the thing: if you want to concentrate on maximum measured performance from a single-ended amp, please save $300 and have a look at Magni Heresy. It’s a very nice little amp that won’t send you down the balanced rabbit-hole.

And of course there will be other comments. Some are gonna want the preamp outputs to switch automatically when headphones are plugged in (neat trick with XLRs, so yeah, it’s a manual front switch), or some might want remote control (for a desktop amp, we think that’s kinda weird, for a preamp intended to be used in a 2-channel system, it makes more sense), some will want all-new DAC or phono cards (but the DAC and phono cards we have are very good).

So. Yeah. Sigh.

Remember, we do have a chapter entitled, “You can’t always get what you want.”

Sometimes I wish we could do bespoke stuff. But stocking would be crazy, or everything would be build-to-order so shipping might get super slow, and how do you document all the different variations so we can support it in the future?

Sorry about that. I think we’re stuck doing fun, high-value audio products for the foreseeable future…which is what we’ve always wanted to do.

It’s been an odyssey getting to this day. Even though Jotunheim 2 looks similar to the first from the outside, it’s really a whole new start. It’s really the ultimate expression of our (current) unique analog approaches, the first Nexus™ and Continuity S™ power amp.

Aside: this is “the promised land” alluded to in the title. Many Schiit fans have been waiting for such an amp. Most normal humans don’t care about our buzzword bingo. Both attitudes are fine. Nexus is something I never expected to find, a true differential topology that doesn’t have an n/n+1 gain structure and provides high-impedance inputs for both positive and negative phases (and I still don’t know if it’s unique), and Continuity has been noted by Broskie and Cordell as addressing one of the problems with Class AB amps (but it’s not exactly efficient itself, at least in original form). Here’s the thing: what if there are other promised lands to be discovered (this is pretty much certain, though there’s nothing on my slate for now)? Or what if those lands really did lie in the golden age of tubes past (not so sure about that)?

Beyond our buzzword bingo, Jotunheim 2 is the result of obsessive tweaking across the board…down to really tiny stuff like Schottky rectifiers in the main power supply to further enhance efficiency, to many, many revs of the truly-constant-voltage Vbe multiplier bias to make the amp run even more consistently, to the hidden Gap Pad that increases heatsinking, to the many iterations of the operational point servo, to the adjustments on open-loop gain and new compensation approaches…this amp is one I’m really proud of.

I hope you enjoy Jotunheim 2 as much as I do!
 
Last edited:
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Dec 16, 2020 at 1:57 PM Post #68,290 of 72,779

darkarn

1000+ Head-Fier
Joined
Mar 16, 2012
Posts
1,141
Likes
390
2020 Chapter 16:
The Promised Land?



So now there’s Jotunheim 2.

jotunheim 2 insitu 1920.jpgHere’s what’s the same as Jotunheim: the bottom chassis, the transformer, and the super-duper Alps RK27114 “Blue Velvet” potentiometer.

Here’s what’s different: Nexus™. Continuity S™. Matched and supermatched parts throughout. A whole new linear power supply, with much lower noise. Higher power output. Lower distortion. Better performance. Switchable preamp outputs.

No, wait, I forgot something else that’s the same: the price.

As in, Jotunheim 2 is still $399.

Sounds crazy? It is, a bit. It’s crazy enough that we’re billing Jotunheim 2 as “the best $2400 amp you can buy for $400.”

Oh wait.

Someone’s pissed now.

Crossed arms. Flaring nostils.

“How can you bill Jotunheim 2 as the equal of a $2400 amp!” you shout. “That’s just marketing hype! Not a fair comparison at all!”

Hmm.

Well, okay. Gotcha. But please have a look at what’s available that is
  1. really truly balanced and differential
  2. really and truly fully discrete
  3. using parts like Alps RK27114 “Blue Velvet” potentiometers
  4. has a 100% internal, 100% linear power supply
  5. has insane attention paid to parts quality, including using 1% front-end matched JFETs and 10% matched BJTs throughout—in the input, voltage gain, and output stages
  6. provides tons of power for hard-to-drive headphones AND is super-quiet for the most sensitive IEMs.
And, you know what? Unless you’re talking megadollar amps, there’s exactly nothing out there.

As in zero. Nada. Zip.

Everything else at Jotunheim 2’s price point is simply another IC-based amp. Nothing wrong with that—we do that in Magnius, at $199—but it isn’t an all-out assault on making the best possible product for your desktop.

Go ahead. See what else is out there. Do the research. Take the time. Come back to us.

And ya gotta admit…Jotunheim 2 is a helluva thing, ain’t it?


The Road To 2

The original Jotunheim was a fundamental re-think of every desktop amp we’d done before. When we introduced it in 2016, it introduced the “modular desktop control center” concept that allows you to choose a module (DAC or phono) to tailor the product to your needs, and to help ensure that you’ll be ready for future changes in DAC technology. The modular idea was so successful we took across the line to Lyr 3 and Asgard 3…and eventually even used the same modules in Ragnarok 2.

For a long time, I thought Jotunheim was really the best we could do in a solid-state amp of that size. But I always play with new ideas, including one that led to the development of our Nexus™ topology.

In fact, Nexus was born in a Jotunheim. Or at least kinda. I mean, it was a very hacked-up Jotunheim layout, with cards stacked on top…

Ergh. Let me back up and talk about prototyping.

Prototyping can be a giant pain in the ass, because when you’re operating at the low noise and distortion levels of Jotunheim or Jotunheim 2, you really should be starting with a PC board layout. Because the layout matters. A lot.

But doing a new layout for each prototype, and stuffing the entire thing, including the power supply, the connectors, the controls, etc is a lot of work. And I had four or five ideas on how to improve the performance of the Pivot Point stage in Jotunheim. Which would mean four or five full layouts (or more, if I wanted to do variations). And then even more if I wanted to tweak a few.

So, being lazy, here’s what I did: I ripped out the entire gain stage of Jotunheim and laid out the board with headers so I could just drop small cards into the power supply and I/O functions. Then I only had to lay out one small board, one channel only, and then drop them into the “sled” to see how they worked.

Yeah. I know. I’m lazy.

And yeah, I know. Some of you want a Jotunheim where you can swap out different kinds of gain stages. Let me make this easy: absolutely not.

Why? Not because we hate you, but because that’s simply too many variations. Too many different Jotunheims to stock. Imagine it: choose one of two DACs, or a phono stage, one of two or three gain stages, one of two colors…Alex would have my head on a pike.

So. No. No gain-stage-modular Jotunheims.

Anyway, back to the story. I had several ideas to try to improve on Pivot Point. The first two offered some interesting variation, in terms of distortion profile and perceived sonics, but the third—the most questionable—surprised the hell out of me. As in, it didn’t display the N/N+1 gain structure I expected of the inverting and noninverting inputs, while still offering high impedance inputs on both side. Which made it that mythical “ideal” differential gain stage I never thought I’d achieve.

Super exciting! But also super problematic. Early Nexus stages had very low VAS gain, and tended to drift off its bias center. It would work good for a while, then as the stage differentially warmed, it would drift off and measure (and sound) like ass.

I tried several ways to fix this, including passive approaches that tried to use the thermal drift of the opposite side to cancel the other, and complex operational-point-servo approaches that used up to three servos to try to keep things in line.

Nothing worked.

Well…except sometimes.

Which made no sense. Why did it work sometimes, but not others? I tried some other layouts, trying to play the thermal and operational points against each other, but again, sometimes they worked, and sometimes they didn’t.

The problem was, I thought, if the devices were perfect they’d never be able to get off center…

But to do that, we’d need tightly matched parts.

And matching parts is insane, or maybe impossible. In the old days at Sumo, we had teams of people matching transistors by hand, painting the tops of the TO-92 devices with a rainbow of fingernail polish to denote their grades…but those were thru-hole parts. SMD? Heck, how would you even start with that?

But then I found entire lines of gain-matched transistor arrays, already done, already SMD, and affordable. Suddenly the whole idea didn’t seem so crazy.

The last frontier were the input JFETs. I contacted our purchasing partners and asked if they could match and re-reel them. The answer was yes!

And suddenly, Nexus worked all the time.

But even then, Nexus wasn’t exactly what I thought appropriate to an affordable amplifier. That’s why it went into big dollar stuff, like Ragnarok 2, to start. A low-current iteration for Freya S just barely worked out.

And then, when it was time for Jotunheim R, Nexus made sense. Jotunheim R would never be inexpensive, with its limited production and heroic design for driving ribbon headphones. So it got Nexus too.

But when it was time to look at Jotunheim 2…hmm.

Actually, I’d been looking at Jotunheim 2 since long before Jotunheim R. And I always wanted to get Nexus into it. But with its cost constraints, it wasn’t super appealing. I knew people wanted switchable preamp outputs, which would take a couple more relays and another switch, which would already increase cost. Going to Nexus would increase cost even more.

And…people also started asking for Continuity™, our constant transconductance stage, in everything, once it showed up in Lyr 3 and Aegir.

But Continuity™, while more efficient than Class A, is still and inefficient stage. Trying to shoehorn that into Jotunheim would require more outputs—and, worse, much higher power dissipation (or much lower power output.)

Still, I had to try.

So I laid out a Jotunheim 2 prototype with the whole schmear: Nexus™ and Continuity™.

It did a little over 1 watt into 32 ohms.

Sigh. Yeah, sorry, guys, I’m not sure the world would accept a successor amp with 1/5 the output of its ancestor. Nope, nope, nope. Not going there.

So I did one without Continuity.

This one did the power output, and it sounded pretty good, but it lost something. Yeah, I know, subjective BS and all, but whatever.

What I really needed was something like Continuity…but more efficient.

Aside: the problem with Continuity is the lower the standing bias, the larger the sense resistors have to be…which means the higher the voltage loss, and thus the lower efficiency. In some amps, like Lyr, Asgard, and Aegir, this works great. But if you’re going for an amp that isn’t a room heater and still has good power output, it’s not the first choice.

And that’s what started a more-than-year-long quest to try to get Continuity’s efficiency up. This comprised many new boards, including some truly wacky things with gain on the sense resistor and super-complex output arrangements. These all either:
  1. Didn’t work
  2. Didn’t improve efficiency
  3. Were unstable and unusable
  4. Sounded like butt
  5. All of the above
I was just about ready to give up and do a Jotunheim 2 with a conventional Class AB output stage (it did sound fine, after some tweaking, but you always wonder what you’re missing, right?) when an alternate idea came to me, one that didn’t use the sense resistor in a way that threw away voltage swing. It wouldn’t be exactly like Continuity, but it would counter the transconductance droop…by acting a bit more like a supercharger that came in only when current needs were highest.

Hence, the Continuity Supercharger, or Continuity S™.

The results? Jotunheim 2 now does 7.2W RMS into 32 ohms at 1% THD, up from 5W on the Jotunheim. (We rate it a bit less at 6W RMS, because that's how we do things around here.)

Holy moly.

And there you have it: Nexus, Continuity S…and preamp output switching, and the same crazy big-ass Alps potentiometer, and still an all-linear supply and modular design, the same steel and aluminum chassis, the same made-in-USA-ness…

For the same price.


But What About…

I personally think Jotunheim 2 is pretty much the best thing we can do at its size and price. And Jotunheim 2, at least the final version with Continuity S, has displaced Lyr 3 and Asgard 3 at home. Yes, even Lyr 3. Lyr 3 is a great amp, and, in the final analysis, might be the right amp for someone else. And Asgard 3 is an insane value, a fun and friendly amp that might be the end game for most sane humans, especially if you don’t want to go down the balanced headphone rabbit-hole.

But Jotunheim 2…it’s really, really special. I personally think “the best $2400 amp you can get for $400” isn’t all hype. Again, compare apples to apples, and factor in the discrete design, the differential topology, the insane parts quality, the obsessive matching…and the list of amps gets pretty short.

But of course there are always opinions, and some of those opinions will center around the discrete nature of Jotunheim 2. Some will ask, “Why discrete when integrated options measure better?”

And yeah, we hear you. Magnius measures better than Jotunheim 2. Magnius is also half the price, so if you want measurements, you can save a ton of money.

But here’s the thing: a lot of people like discrete amps. A lot of people like the more bespoke approach, the lower open loop gain, the freedom to do some interesting topologies that may not be available on any IC (like Nexus). And that’s perfectly fine. Some people like Tesla, some people like Subaru, some people like Ferrari.

We personally think there’s room in our line for an affordable uber-measurement amp, and a more expensive discrete design, which also has some distinguishing features like modularity. As I like to say, we’ll see how it goes.

And some people will note that the single-ended outputs don’t measure as well as the balanced outputs. Yeppers, 100% right. That’s what happens when you use one phase of a balanced output and lose all the distortion cancellation from a differential topology.

Aside: it also gives you a distortion profile that’s reminiscent of a tube amp. Hmmmmmmmmmm….

But is this a bug or a feature? Maybe the single-ended output sounds a bit softer and tubier because of its distortion profile. Or maybe all distortion is sufficiently below the transducer distortion that you can’t hear it at all, in which case the argument is moot. Or maybe most people choosing a differential amp will typically be using it with balanced headphones, and the single-ended output is a convenience.

In any case, this is literally the same approach we took with the original Jotunheim, and the approach we used in Ragnarok, and the approach we used in Magnius, because that’s what our customers said they preferred—using one half of the differential output, rather than summing to single-ended.

And it’s not like we’re hiding the difference in performance. The full APx555 report is downloadable, and it covers both balanced and single-ended output.

So, are we cool?

Yes? Great.

No? Well, here’s the thing: if you want to concentrate on maximum measured performance from a single-ended amp, please save $300 and have a look at Magni Heresy. It’s a very nice little amp that won’t send you down the balanced rabbit-hole.

And of course there will be other comments. Some are gonna want the preamp outputs to switch automatically when headphones are plugged in (neat trick with XLRs, so yeah, it’s a manual front switch), or some might want remote control (for a desktop amp, we think that’s kinda weird, for a preamp intended to be used in a 2-channel system, it makes more sense), some will want all-new DAC or phono cards (but the DAC and phono cards we have are very good).

So. Yeah. Sigh.

Remember, we do have a chapter entitled, “You can’t always get what you want.”

Sometimes I wish we could do bespoke stuff. But stocking would be crazy, or everything would be build-to-order so shipping might get super slow, and how do you document all the different variations so we can support it in the future?

Sorry about that. I think we’re stuck doing fun, high-value audio products for the foreseeable future…which is what we’ve always wanted to do.

It’s been an odyssey getting to this day. Even though Jotunheim 2 looks similar to the first from the outside, it’s really a whole new start. It’s really the ultimate expression of our (current) unique analog approaches, the first Nexus™ and Continuity S™ power amp.

Aside: this is “the promised land” alluded to in the title. Many Schiit fans have been waiting for such an amp. Most normal humans don’t care about our buzzword bingo. Both attitudes are fine. Nexus is something I never expected to find, a true differential topology that doesn’t have an n/n+1 gain structure and provides high-impedance inputs for both positive and negative phases (and I still don’t know if it’s unique), and Continuity has been noted by Broskie and Cordell as addressing one of the problems with Class AB amps (but it’s not exactly efficient itself, at least in original form). Here’s the thing: what if there are other promised lands to be discovered (this is pretty much certain, though there’s nothing on my slate for now)? Or what if those lands really did lie in the golden age of tubes past (not so sure about that)?

Beyond our buzzword bingo, Jotunheim 2 is the result of obsessive tweaking across the board…down to really tiny stuff like Schottky rectifiers in the main power supply to further enhance efficiency, to many, many revs of the truly-constant-voltage Vbe multiplier bias to make the amp run even more consistently, to the hidden Gap Pad that increases heatsinking, to the many iterations of the operational point servo, to the adjustments on open-loop gain and new compensation approaches…this amp is one I’m really proud of.

I hope you enjoy Jotunheim 2 as much as I do!

Whew, looks like we finally reached the age of a good and cheap balanced amp

Sounds like lots of us will be asking about it during the Schiitr Meet later. Well done Jason!
 
Dec 16, 2020 at 2:00 PM Post #68,291 of 72,779

Ableza

Headphoneus Supremus
Joined
Jan 18, 2014
Posts
4,655
Likes
16,241
Location
Valley of the Sun
There is now. When lots of people are using the term and everybody agrees about what it means, then it has entered the standard lexicon. Language is a living, evolving entity.
Hah. Yea, and many people don't know the proper usage of "their" vs. "they're" but that does not make the misuse acceptable. :)
 
Dec 16, 2020 at 2:08 PM Post #68,292 of 72,779

Mike-WI

500+ Head-Fier
Joined
Oct 31, 2011
Posts
591
Likes
688
Location
WI, USA
2020 Chapter 16:
The Promised Land?



So now there’s Jotunheim 2.

jotunheim 2 insitu 1920.jpgHere’s what’s the same as Jotunheim: the bottom chassis, the transformer, and the super-duper Alps RK27114 “Blue Velvet” potentiometer.

Here’s what’s different: Nexus™. Continuity S™. Matched and supermatched parts throughout. A whole new linear power supply, with much lower noise. Higher power output. Lower distortion. Better performance. Switchable preamp outputs.

No, wait, I forgot something else that’s the same: the price.

As in, Jotunheim 2 is still $399.

Sounds crazy? It is, a bit. It’s crazy enough that we’re billing Jotunheim 2 as “the best $2400 amp you can buy for $400.”

Oh wait.

Someone’s pissed now.

Crossed arms. Flaring nostils.

“How can you bill Jotunheim 2 as the equal of a $2400 amp!” you shout. “That’s just marketing hype! Not a fair comparison at all!”

Hmm.

Well, okay. Gotcha. But please have a look at what’s available that is
  1. really truly balanced and differential
  2. really and truly fully discrete
  3. using parts like Alps RK27114 “Blue Velvet” potentiometers
  4. has a 100% internal, 100% linear power supply
  5. has insane attention paid to parts quality, including using 1% front-end matched JFETs and 10% matched BJTs throughout—in the input, voltage gain, and output stages
  6. provides tons of power for hard-to-drive headphones AND is super-quiet for the most sensitive IEMs.
And, you know what? Unless you’re talking megadollar amps, there’s exactly nothing out there.

As in zero. Nada. Zip.

Everything else at Jotunheim 2’s price point is simply another IC-based amp. Nothing wrong with that—we do that in Magnius, at $199—but it isn’t an all-out assault on making the best possible product for your desktop.

Go ahead. See what else is out there. Do the research. Take the time. Come back to us.

And ya gotta admit…Jotunheim 2 is a helluva thing, ain’t it?


The Road To 2

The original Jotunheim was a fundamental re-think of every desktop amp we’d done before. When we introduced it in 2016, it introduced the “modular desktop control center” concept that allows you to choose a module (DAC or phono) to tailor the product to your needs, and to help ensure that you’ll be ready for future changes in DAC technology. The modular idea was so successful we took across the line to Lyr 3 and Asgard 3…and eventually even used the same modules in Ragnarok 2.

For a long time, I thought Jotunheim was really the best we could do in a solid-state amp of that size. But I always play with new ideas, including one that led to the development of our Nexus™ topology.

In fact, Nexus was born in a Jotunheim. Or at least kinda. I mean, it was a very hacked-up Jotunheim layout, with cards stacked on top…

Ergh. Let me back up and talk about prototyping.

Prototyping can be a giant pain in the ass, because when you’re operating at the low noise and distortion levels of Jotunheim or Jotunheim 2, you really should be starting with a PC board layout. Because the layout matters. A lot.

But doing a new layout for each prototype, and stuffing the entire thing, including the power supply, the connectors, the controls, etc is a lot of work. And I had four or five ideas on how to improve the performance of the Pivot Point stage in Jotunheim. Which would mean four or five full layouts (or more, if I wanted to do variations). And then even more if I wanted to tweak a few.

So, being lazy, here’s what I did: I ripped out the entire gain stage of Jotunheim and laid out the board with headers so I could just drop small cards into the power supply and I/O functions. Then I only had to lay out one small board, one channel only, and then drop them into the “sled” to see how they worked.

Yeah. I know. I’m lazy.

And yeah, I know. Some of you want a Jotunheim where you can swap out different kinds of gain stages. Let me make this easy: absolutely not.

Why? Not because we hate you, but because that’s simply too many variations. Too many different Jotunheims to stock. Imagine it: choose one of two DACs, or a phono stage, one of two or three gain stages, one of two colors…Alex would have my head on a pike.

So. No. No gain-stage-modular Jotunheims.

Anyway, back to the story. I had several ideas to try to improve on Pivot Point. The first two offered some interesting variation, in terms of distortion profile and perceived sonics, but the third—the most questionable—surprised the hell out of me. As in, it didn’t display the N/N+1 gain structure I expected of the inverting and noninverting inputs, while still offering high impedance inputs on both side. Which made it that mythical “ideal” differential gain stage I never thought I’d achieve.

Super exciting! But also super problematic. Early Nexus stages had very low VAS gain, and tended to drift off its bias center. It would work good for a while, then as the stage differentially warmed, it would drift off and measure (and sound) like ass.

I tried several ways to fix this, including passive approaches that tried to use the thermal drift of the opposite side to cancel the other, and complex operational-point-servo approaches that used up to three servos to try to keep things in line.

Nothing worked.

Well…except sometimes.

Which made no sense. Why did it work sometimes, but not others? I tried some other layouts, trying to play the thermal and operational points against each other, but again, sometimes they worked, and sometimes they didn’t.

The problem was, I thought, if the devices were perfect they’d never be able to get off center…

But to do that, we’d need tightly matched parts.

And matching parts is insane, or maybe impossible. In the old days at Sumo, we had teams of people matching transistors by hand, painting the tops of the TO-92 devices with a rainbow of fingernail polish to denote their grades…but those were thru-hole parts. SMD? Heck, how would you even start with that?

But then I found entire lines of gain-matched transistor arrays, already done, already SMD, and affordable. Suddenly the whole idea didn’t seem so crazy.

The last frontier were the input JFETs. I contacted our purchasing partners and asked if they could match and re-reel them. The answer was yes!

And suddenly, Nexus worked all the time.

But even then, Nexus wasn’t exactly what I thought appropriate to an affordable amplifier. That’s why it went into big dollar stuff, like Ragnarok 2, to start. A low-current iteration for Freya S just barely worked out.

And then, when it was time for Jotunheim R, Nexus made sense. Jotunheim R would never be inexpensive, with its limited production and heroic design for driving ribbon headphones. So it got Nexus too.

But when it was time to look at Jotunheim 2…hmm.

Actually, I’d been looking at Jotunheim 2 since long before Jotunheim R. And I always wanted to get Nexus into it. But with its cost constraints, it wasn’t super appealing. I knew people wanted switchable preamp outputs, which would take a couple more relays and another switch, which would already increase cost. Going to Nexus would increase cost even more.

And…people also started asking for Continuity™, our constant transconductance stage, in everything, once it showed up in Lyr 3 and Aegir.

But Continuity™, while more efficient than Class A, is still and inefficient stage. Trying to shoehorn that into Jotunheim would require more outputs—and, worse, much higher power dissipation (or much lower power output.)

Still, I had to try.

So I laid out a Jotunheim 2 prototype with the whole schmear: Nexus™ and Continuity™.

It did a little over 1 watt into 32 ohms.

Sigh. Yeah, sorry, guys, I’m not sure the world would accept a successor amp with 1/5 the output of its ancestor. Nope, nope, nope. Not going there.

So I did one without Continuity.

This one did the power output, and it sounded pretty good, but it lost something. Yeah, I know, subjective BS and all, but whatever.

What I really needed was something like Continuity…but more efficient.

Aside: the problem with Continuity is the lower the standing bias, the larger the sense resistors have to be…which means the higher the voltage loss, and thus the lower efficiency. In some amps, like Lyr, Asgard, and Aegir, this works great. But if you’re going for an amp that isn’t a room heater and still has good power output, it’s not the first choice.

And that’s what started a more-than-year-long quest to try to get Continuity’s efficiency up. This comprised many new boards, including some truly wacky things with gain on the sense resistor and super-complex output arrangements. These all either:
  1. Didn’t work
  2. Didn’t improve efficiency
  3. Were unstable and unusable
  4. Sounded like butt
  5. All of the above
I was just about ready to give up and do a Jotunheim 2 with a conventional Class AB output stage (it did sound fine, after some tweaking, but you always wonder what you’re missing, right?) when an alternate idea came to me, one that didn’t use the sense resistor in a way that threw away voltage swing. It wouldn’t be exactly like Continuity, but it would counter the transconductance droop…by acting a bit more like a supercharger that came in only when current needs were highest.

Hence, the Continuity Supercharger, or Continuity S™.

The results? Jotunheim 2 now does 7.2W RMS into 32 ohms at 1% THD, up from 5W on the Jotunheim. (We rate it a bit less at 6W RMS, because that's how we do things around here.)

Holy moly.

And there you have it: Nexus, Continuity S…and preamp output switching, and the same crazy big-ass Alps potentiometer, and still an all-linear supply and modular design, the same steel and aluminum chassis, the same made-in-USA-ness…

For the same price.


But What About…

I personally think Jotunheim 2 is pretty much the best thing we can do at its size and price. And Jotunheim 2, at least the final version with Continuity S, has displaced Lyr 3 and Asgard 3 at home. Yes, even Lyr 3. Lyr 3 is a great amp, and, in the final analysis, might be the right amp for someone else. And Asgard 3 is an insane value, a fun and friendly amp that might be the end game for most sane humans, especially if you don’t want to go down the balanced headphone rabbit-hole.

But Jotunheim 2…it’s really, really special. I personally think “the best $2400 amp you can get for $400” isn’t all hype. Again, compare apples to apples, and factor in the discrete design, the differential topology, the insane parts quality, the obsessive matching…and the list of amps gets pretty short.

But of course there are always opinions, and some of those opinions will center around the discrete nature of Jotunheim 2. Some will ask, “Why discrete when integrated options measure better?”

And yeah, we hear you. Magnius measures better than Jotunheim 2. Magnius is also half the price, so if you want measurements, you can save a ton of money.

But here’s the thing: a lot of people like discrete amps. A lot of people like the more bespoke approach, the lower open loop gain, the freedom to do some interesting topologies that may not be available on any IC (like Nexus). And that’s perfectly fine. Some people like Tesla, some people like Subaru, some people like Ferrari.

We personally think there’s room in our line for an affordable uber-measurement amp, and a more expensive discrete design, which also has some distinguishing features like modularity. As I like to say, we’ll see how it goes.

And some people will note that the single-ended outputs don’t measure as well as the balanced outputs. Yeppers, 100% right. That’s what happens when you use one phase of a balanced output and lose all the distortion cancellation from a differential topology.

Aside: it also gives you a distortion profile that’s reminiscent of a tube amp. Hmmmmmmmmmm….

But is this a bug or a feature? Maybe the single-ended output sounds a bit softer and tubier because of its distortion profile. Or maybe all distortion is sufficiently below the transducer distortion that you can’t hear it at all, in which case the argument is moot. Or maybe most people choosing a differential amp will typically be using it with balanced headphones, and the single-ended output is a convenience.

In any case, this is literally the same approach we took with the original Jotunheim, and the approach we used in Ragnarok, and the approach we used in Magnius, because that’s what our customers said they preferred—using one half of the differential output, rather than summing to single-ended.

And it’s not like we’re hiding the difference in performance. The full APx555 report is downloadable, and it covers both balanced and single-ended output.

So, are we cool?

Yes? Great.

No? Well, here’s the thing: if you want to concentrate on maximum measured performance from a single-ended amp, please save $300 and have a look at Magni Heresy. It’s a very nice little amp that won’t send you down the balanced rabbit-hole.

And of course there will be other comments. Some are gonna want the preamp outputs to switch automatically when headphones are plugged in (neat trick with XLRs, so yeah, it’s a manual front switch), or some might want remote control (for a desktop amp, we think that’s kinda weird, for a preamp intended to be used in a 2-channel system, it makes more sense), some will want all-new DAC or phono cards (but the DAC and phono cards we have are very good).

So. Yeah. Sigh.

Remember, we do have a chapter entitled, “You can’t always get what you want.”

Sometimes I wish we could do bespoke stuff. But stocking would be crazy, or everything would be build-to-order so shipping might get super slow, and how do you document all the different variations so we can support it in the future?

Sorry about that. I think we’re stuck doing fun, high-value audio products for the foreseeable future…which is what we’ve always wanted to do.

It’s been an odyssey getting to this day. Even though Jotunheim 2 looks similar to the first from the outside, it’s really a whole new start. It’s really the ultimate expression of our (current) unique analog approaches, the first Nexus™ and Continuity S™ power amp.

Aside: this is “the promised land” alluded to in the title. Many Schiit fans have been waiting for such an amp. Most normal humans don’t care about our buzzword bingo. Both attitudes are fine. Nexus is something I never expected to find, a true differential topology that doesn’t have an n/n+1 gain structure and provides high-impedance inputs for both positive and negative phases (and I still don’t know if it’s unique), and Continuity has been noted by Broskie and Cordell as addressing one of the problems with Class AB amps (but it’s not exactly efficient itself, at least in original form). Here’s the thing: what if there are other promised lands to be discovered (this is pretty much certain, though there’s nothing on my slate for now)? Or what if those lands really did lie in the golden age of tubes past (not so sure about that)?

Beyond our buzzword bingo, Jotunheim 2 is the result of obsessive tweaking across the board…down to really tiny stuff like Schottky rectifiers in the main power supply to further enhance efficiency, to many, many revs of the truly-constant-voltage Vbe multiplier bias to make the amp run even more consistently, to the hidden Gap Pad that increases heatsinking, to the many iterations of the operational point servo, to the adjustments on open-loop gain and new compensation approaches…this amp is one I’m really proud of.

I hope you enjoy Jotunheim 2 as much as I do!
Very cool for multiple reasons.
I have a Jot MB + Jot for pre-amp (to whole house audio) switch.
Nicely integrated.
"Giant-slaying"
 
Dec 16, 2020 at 2:16 PM Post #68,295 of 72,779

banda

100+ Head-Fier
Joined
Mar 28, 2020
Posts
104
Likes
38
Location
UK
2020 Chapter 16:
The Promised Land?



So now there’s Jotunheim 2.

jotunheim 2 insitu 1920.jpgHere’s what’s the same as Jotunheim: the bottom chassis, the transformer, and the super-duper Alps RK27114 “Blue Velvet” potentiometer.

Here’s what’s different: Nexus™. Continuity S™. Matched and supermatched parts throughout. A whole new linear power supply, with much lower noise. Higher power output. Lower distortion. Better performance. Switchable preamp outputs.

No, wait, I forgot something else that’s the same: the price.

As in, Jotunheim 2 is still $399.

Sounds crazy? It is, a bit. It’s crazy enough that we’re billing Jotunheim 2 as “the best $2400 amp you can buy for $400.”

Oh wait.

Someone’s pissed now.

Crossed arms. Flaring nostils.

“How can you bill Jotunheim 2 as the equal of a $2400 amp!” you shout. “That’s just marketing hype! Not a fair comparison at all!”

Hmm.

Well, okay. Gotcha. But please have a look at what’s available that is
  1. really truly balanced and differential
  2. really and truly fully discrete
  3. using parts like Alps RK27114 “Blue Velvet” potentiometers
  4. has a 100% internal, 100% linear power supply
  5. has insane attention paid to parts quality, including using 1% front-end matched JFETs and 10% matched BJTs throughout—in the input, voltage gain, and output stages
  6. provides tons of power for hard-to-drive headphones AND is super-quiet for the most sensitive IEMs.
And, you know what? Unless you’re talking megadollar amps, there’s exactly nothing out there.

As in zero. Nada. Zip.

Everything else at Jotunheim 2’s price point is simply another IC-based amp. Nothing wrong with that—we do that in Magnius, at $199—but it isn’t an all-out assault on making the best possible product for your desktop.

Go ahead. See what else is out there. Do the research. Take the time. Come back to us.

And ya gotta admit…Jotunheim 2 is a helluva thing, ain’t it?


The Road To 2

The original Jotunheim was a fundamental re-think of every desktop amp we’d done before. When we introduced it in 2016, it introduced the “modular desktop control center” concept that allows you to choose a module (DAC or phono) to tailor the product to your needs, and to help ensure that you’ll be ready for future changes in DAC technology. The modular idea was so successful we took across the line to Lyr 3 and Asgard 3…and eventually even used the same modules in Ragnarok 2.

For a long time, I thought Jotunheim was really the best we could do in a solid-state amp of that size. But I always play with new ideas, including one that led to the development of our Nexus™ topology.

In fact, Nexus was born in a Jotunheim. Or at least kinda. I mean, it was a very hacked-up Jotunheim layout, with cards stacked on top…

Ergh. Let me back up and talk about prototyping.

Prototyping can be a giant pain in the ass, because when you’re operating at the low noise and distortion levels of Jotunheim or Jotunheim 2, you really should be starting with a PC board layout. Because the layout matters. A lot.

But doing a new layout for each prototype, and stuffing the entire thing, including the power supply, the connectors, the controls, etc is a lot of work. And I had four or five ideas on how to improve the performance of the Pivot Point stage in Jotunheim. Which would mean four or five full layouts (or more, if I wanted to do variations). And then even more if I wanted to tweak a few.

So, being lazy, here’s what I did: I ripped out the entire gain stage of Jotunheim and laid out the board with headers so I could just drop small cards into the power supply and I/O functions. Then I only had to lay out one small board, one channel only, and then drop them into the “sled” to see how they worked.

Yeah. I know. I’m lazy.

And yeah, I know. Some of you want a Jotunheim where you can swap out different kinds of gain stages. Let me make this easy: absolutely not.

Why? Not because we hate you, but because that’s simply too many variations. Too many different Jotunheims to stock. Imagine it: choose one of two DACs, or a phono stage, one of two or three gain stages, one of two colors…Alex would have my head on a pike.

So. No. No gain-stage-modular Jotunheims.

Anyway, back to the story. I had several ideas to try to improve on Pivot Point. The first two offered some interesting variation, in terms of distortion profile and perceived sonics, but the third—the most questionable—surprised the hell out of me. As in, it didn’t display the N/N+1 gain structure I expected of the inverting and noninverting inputs, while still offering high impedance inputs on both side. Which made it that mythical “ideal” differential gain stage I never thought I’d achieve.

Super exciting! But also super problematic. Early Nexus stages had very low VAS gain, and tended to drift off its bias center. It would work good for a while, then as the stage differentially warmed, it would drift off and measure (and sound) like ass.

I tried several ways to fix this, including passive approaches that tried to use the thermal drift of the opposite side to cancel the other, and complex operational-point-servo approaches that used up to three servos to try to keep things in line.

Nothing worked.

Well…except sometimes.

Which made no sense. Why did it work sometimes, but not others? I tried some other layouts, trying to play the thermal and operational points against each other, but again, sometimes they worked, and sometimes they didn’t.

The problem was, I thought, if the devices were perfect they’d never be able to get off center…

But to do that, we’d need tightly matched parts.

And matching parts is insane, or maybe impossible. In the old days at Sumo, we had teams of people matching transistors by hand, painting the tops of the TO-92 devices with a rainbow of fingernail polish to denote their grades…but those were thru-hole parts. SMD? Heck, how would you even start with that?

But then I found entire lines of gain-matched transistor arrays, already done, already SMD, and affordable. Suddenly the whole idea didn’t seem so crazy.

The last frontier were the input JFETs. I contacted our purchasing partners and asked if they could match and re-reel them. The answer was yes!

And suddenly, Nexus worked all the time.

But even then, Nexus wasn’t exactly what I thought appropriate to an affordable amplifier. That’s why it went into big dollar stuff, like Ragnarok 2, to start. A low-current iteration for Freya S just barely worked out.

And then, when it was time for Jotunheim R, Nexus made sense. Jotunheim R would never be inexpensive, with its limited production and heroic design for driving ribbon headphones. So it got Nexus too.

But when it was time to look at Jotunheim 2…hmm.

Actually, I’d been looking at Jotunheim 2 since long before Jotunheim R. And I always wanted to get Nexus into it. But with its cost constraints, it wasn’t super appealing. I knew people wanted switchable preamp outputs, which would take a couple more relays and another switch, which would already increase cost. Going to Nexus would increase cost even more.

And…people also started asking for Continuity™, our constant transconductance stage, in everything, once it showed up in Lyr 3 and Aegir.

But Continuity™, while more efficient than Class A, is still and inefficient stage. Trying to shoehorn that into Jotunheim would require more outputs—and, worse, much higher power dissipation (or much lower power output.)

Still, I had to try.

So I laid out a Jotunheim 2 prototype with the whole schmear: Nexus™ and Continuity™.

It did a little over 1 watt into 32 ohms.

Sigh. Yeah, sorry, guys, I’m not sure the world would accept a successor amp with 1/5 the output of its ancestor. Nope, nope, nope. Not going there.

So I did one without Continuity.

This one did the power output, and it sounded pretty good, but it lost something. Yeah, I know, subjective BS and all, but whatever.

What I really needed was something like Continuity…but more efficient.

Aside: the problem with Continuity is the lower the standing bias, the larger the sense resistors have to be…which means the higher the voltage loss, and thus the lower efficiency. In some amps, like Lyr, Asgard, and Aegir, this works great. But if you’re going for an amp that isn’t a room heater and still has good power output, it’s not the first choice.

And that’s what started a more-than-year-long quest to try to get Continuity’s efficiency up. This comprised many new boards, including some truly wacky things with gain on the sense resistor and super-complex output arrangements. These all either:
  1. Didn’t work
  2. Didn’t improve efficiency
  3. Were unstable and unusable
  4. Sounded like butt
  5. All of the above
I was just about ready to give up and do a Jotunheim 2 with a conventional Class AB output stage (it did sound fine, after some tweaking, but you always wonder what you’re missing, right?) when an alternate idea came to me, one that didn’t use the sense resistor in a way that threw away voltage swing. It wouldn’t be exactly like Continuity, but it would counter the transconductance droop…by acting a bit more like a supercharger that came in only when current needs were highest.

Hence, the Continuity Supercharger, or Continuity S™.

The results? Jotunheim 2 now does 7.2W RMS into 32 ohms at 1% THD, up from 5W on the Jotunheim. (We rate it a bit less at 6W RMS, because that's how we do things around here.)

Holy moly.

And there you have it: Nexus, Continuity S…and preamp output switching, and the same crazy big-ass Alps potentiometer, and still an all-linear supply and modular design, the same steel and aluminum chassis, the same made-in-USA-ness…

For the same price.


But What About…

I personally think Jotunheim 2 is pretty much the best thing we can do at its size and price. And Jotunheim 2, at least the final version with Continuity S, has displaced Lyr 3 and Asgard 3 at home. Yes, even Lyr 3. Lyr 3 is a great amp, and, in the final analysis, might be the right amp for someone else. And Asgard 3 is an insane value, a fun and friendly amp that might be the end game for most sane humans, especially if you don’t want to go down the balanced headphone rabbit-hole.

But Jotunheim 2…it’s really, really special. I personally think “the best $2400 amp you can get for $400” isn’t all hype. Again, compare apples to apples, and factor in the discrete design, the differential topology, the insane parts quality, the obsessive matching…and the list of amps gets pretty short.

But of course there are always opinions, and some of those opinions will center around the discrete nature of Jotunheim 2. Some will ask, “Why discrete when integrated options measure better?”

And yeah, we hear you. Magnius measures better than Jotunheim 2. Magnius is also half the price, so if you want measurements, you can save a ton of money.

But here’s the thing: a lot of people like discrete amps. A lot of people like the more bespoke approach, the lower open loop gain, the freedom to do some interesting topologies that may not be available on any IC (like Nexus). And that’s perfectly fine. Some people like Tesla, some people like Subaru, some people like Ferrari.

We personally think there’s room in our line for an affordable uber-measurement amp, and a more expensive discrete design, which also has some distinguishing features like modularity. As I like to say, we’ll see how it goes.

And some people will note that the single-ended outputs don’t measure as well as the balanced outputs. Yeppers, 100% right. That’s what happens when you use one phase of a balanced output and lose all the distortion cancellation from a differential topology.

Aside: it also gives you a distortion profile that’s reminiscent of a tube amp. Hmmmmmmmmmm….

But is this a bug or a feature? Maybe the single-ended output sounds a bit softer and tubier because of its distortion profile. Or maybe all distortion is sufficiently below the transducer distortion that you can’t hear it at all, in which case the argument is moot. Or maybe most people choosing a differential amp will typically be using it with balanced headphones, and the single-ended output is a convenience.

In any case, this is literally the same approach we took with the original Jotunheim, and the approach we used in Ragnarok, and the approach we used in Magnius, because that’s what our customers said they preferred—using one half of the differential output, rather than summing to single-ended.

And it’s not like we’re hiding the difference in performance. The full APx555 report is downloadable, and it covers both balanced and single-ended output.

So, are we cool?

Yes? Great.

No? Well, here’s the thing: if you want to concentrate on maximum measured performance from a single-ended amp, please save $300 and have a look at Magni Heresy. It’s a very nice little amp that won’t send you down the balanced rabbit-hole.

And of course there will be other comments. Some are gonna want the preamp outputs to switch automatically when headphones are plugged in (neat trick with XLRs, so yeah, it’s a manual front switch), or some might want remote control (for a desktop amp, we think that’s kinda weird, for a preamp intended to be used in a 2-channel system, it makes more sense), some will want all-new DAC or phono cards (but the DAC and phono cards we have are very good).

So. Yeah. Sigh.

Remember, we do have a chapter entitled, “You can’t always get what you want.”

Sometimes I wish we could do bespoke stuff. But stocking would be crazy, or everything would be build-to-order so shipping might get super slow, and how do you document all the different variations so we can support it in the future?

Sorry about that. I think we’re stuck doing fun, high-value audio products for the foreseeable future…which is what we’ve always wanted to do.

It’s been an odyssey getting to this day. Even though Jotunheim 2 looks similar to the first from the outside, it’s really a whole new start. It’s really the ultimate expression of our (current) unique analog approaches, the first Nexus™ and Continuity S™ power amp.

Aside: this is “the promised land” alluded to in the title. Many Schiit fans have been waiting for such an amp. Most normal humans don’t care about our buzzword bingo. Both attitudes are fine. Nexus is something I never expected to find, a true differential topology that doesn’t have an n/n+1 gain structure and provides high-impedance inputs for both positive and negative phases (and I still don’t know if it’s unique), and Continuity has been noted by Broskie and Cordell as addressing one of the problems with Class AB amps (but it’s not exactly efficient itself, at least in original form). Here’s the thing: what if there are other promised lands to be discovered (this is pretty much certain, though there’s nothing on my slate for now)? Or what if those lands really did lie in the golden age of tubes past (not so sure about that)?

Beyond our buzzword bingo, Jotunheim 2 is the result of obsessive tweaking across the board…down to really tiny stuff like Schottky rectifiers in the main power supply to further enhance efficiency, to many, many revs of the truly-constant-voltage Vbe multiplier bias to make the amp run even more consistently, to the hidden Gap Pad that increases heatsinking, to the many iterations of the operational point servo, to the adjustments on open-loop gain and new compensation approaches…this amp is one I’m really proud of.

I hope you enjoy Jotunheim 2 as much as I do!
Oh my god, yes! I didn't think we'd get this this year. Such a great surprise to see this post tonight.
 

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