Magni+

Frequency Response: 20Hz-20Khz, +/-0.02dB

Maximum Power, 16 ohms: 2.8W RMS per channel
Maximum Power, 32 ohms: 2.4W RMS per channel
Maximum Power, 50 ohms: 1.6W RMS per channel
Maximum Power, 300 ohms: 410mW RMS per channel
Maximum Power, 600 ohms: 215mW RMS per channel

THD+N: 

High Gain: Less than 0.0007% (-102dB) ref 1V RMS, 300 ohms
Low Gain: Less than 0.0003% (-110dB) ref 1V RMS, 300 ohms

IMD: 

High Gain: Less than -103dB ref 1V RMS, 300 ohms, CCIF
Low Gain: Less than -112dB ref 1V RMS, 300 ohms, CCIF

SNR: 

High Gain: Greater than 110dB, unweighted, ref to 2V RMS
Low Gain: Greater than 121dB, unweighted, ref to 2V RMS

Crosstalk: Less than -85dB at 1V RMS out

Output Impedance: Less than 0.2 ohms at either gain

Input Impedance: 25k ohms

Gain: -8dB, 0dB, or 14dB, selectable via front switch

Topology: Fully discrete, fully complementary all-bipolar, symmetrical current-feedback design with driver stage and Vbe multiplier, no capacitors in the signal path and DC servo

Protection: Transparent overcurrent sense and protect, DC correction, failsafe DC power input and muting relay

Power Supply: “Wall wart” style 24VA 14VAC transformer, regulated +/- 16V rails with over 8,000uF filter capacitance

Power Consumption: 6W

Size: 5 x 3.5 x 1.25”

Weight: 1 lb

APx555 Report for Magni+

Magni Heretic

Frequency Response: 20Hz-20Khz, +/-0.01dB

Maximum Power, 16 ohms: 2.8W RMS per channel
Maximum Power, 32 ohms: 2.4W RMS per channel
Maximum Power, 50 ohms: 1.6W RMS per channel
Maximum Power, 300 ohms: 410mW RMS per channel
Maximum Power, 600 ohms: 215mW RMS per channel

THD+N: 

High Gain: Less than 0.0002% (-112dB) ref 2V RMS at 300 ohms
Low Gain: Less than 0.0001% (-119dB) ref 2V RMS at 300 ohms

IMD: 

High Gain: Less than -112dB at 1V RMS into 32 ohms, CCIF
Low Gain: Less than -115dB ref 1V RMS into 300 ohms, CCIF

SNR: 

High Gain: Greater than 115dB, unweighted, ref 2V RMS
Low Gain: Greater than 123dB, unweighted, ref 2V RMS

Crosstalk: Less than -86dB, ref 1V out

Output Impedance: Less than 0.33 ohms at either gain

Input Impedance: 50k ohms minimum in all gains

Gain: -10dB, 0dB, or 15dB, selectable via front switch

Topology: OPA1656 op-amp for voltage gain with local feedback, OPA1656 (6 stages per channel) as output buffers with local loops, no overall loop feedback.

Protection: Transparent current sense and protect, DC sense and protect, ESD protect, failsafe DC power input and muting relay

Power Supply: “Wall wart” style 24VA 15VAC transformer, regulated +/- 16V rails with over 8,000uF filter capacitance

Power Consumption: 6W

Size: 5 x 3.5 x 1.25”

Weight: 1 lb

APx Report for Magni Heretic

I don’t know if I buy this whole “no excuses” thing on a $109 product.
Hey, we did raise the price $10.

Over ten years! Has that even kept pace with inflation?
Certainly not. A $99 Magni in 2012 is $127 today.

And you added a bunch of features! Hell, this one has three gain levels. And a front switch for it!
Go ahead, keep doing our marketing for us.

Sigh. Can I get an answer for this whole “no excuses” claim, which I find hard to believe on a product of this price? And I’d prefer a serious answer, not more snark.
Well, we broke it down a bit in the copy, but here’s the thing: Magni really is a no-excuses amp, no matter how you look at it.

• Overall design and quality? It uses insanely high grade stuff, from 0.5% thin-film resistors to silicon caps, it’s totally DC coupled, the power supply uses a ton of filter capacitance, the power output is no joke. And Magni+ is a real, no-joke, 100% discrete design using exotic current feedback, just like amps that cost hundreds (and thousands) more. Magni Heretic is our own unique op-amp topology with no overall feedback and massively parallel output stage based on one of the best op-amps on the planet, the OPA1656.
• Or do you want to talk flexibility? With 2.4W on tap, and three gain levels, including negative gain for IEMs, you’re set for every headphone out there.
• Or are we talking safety? In which case the overcurrent and DC protection systems—both, by the way, 100% transparent and out of the signal path—mean your most treasured headphones have the highest level of protection.
• Or are we talking ideology, in that our products are made in a country (the USA) with everyone being paid well above a living wage.
• Or are we down to looks, which are subjective, but our new (USA-made) advanced-form steel stamped chassis eliminates visible fasteners and looks way sexier…hell, and we even added a milled aluminum knob.

I mean, holy moly, if all of that ain’t “no excuses,” then we don’t know what is.

I see you still have two Magni models, Magni+ and Magni Heretic.
Yep.

Why?
Long story short: we did like, literally, 20 different Magni prototypes (seriously), trying to bring together the measured performance of Magni Heresy and the sonics of Magni 3+, and, when we (almost) achieved it, we weren’t all that thrilled with the resulting device. A voltage-feedback discrete design wasn’t what we were looking for.

I’m sorry, that sounded like a very long story.
Then let’s leave it at this: there are two Magnis, one for people who want an all-discrete exotic current-feedback design, and one for people who want max measurements per dollar.

How do I choose?
I think we covered this in the product description, but here goes again, with more detail:

• Magni+: choose this one if you want an all-discrete headphone amp. Discrete means its made up of lots of individual transistors (well, actually a lot of paired matched transistors now). It’s essentially a mini speaker amp. In fact, it’s very much like a Vidar. It's a super-advanced amp, and we’re very proud of it.
• Magni Heretic: choose this one if you want a 100% op-amp-based headphone amp that delivers spectacular measurements. Thank the high-quality op-amps used: OPA1656 throuughout—both input and (6) OPA1656 stages per channel for output. Or choose this one if you like red--it has a red bottom chassis.

Which sounds best?
Ah hell no, we aren’t falling for that. You tell us.

At least give us a hint!
We think both Magnis sound very, very good, or else we wouldn’t offer them. We developed the Magni Heretic largely to see what could be accomplished with a simple topology and modern op-amps, but we’re very pleased with the way it came out. At the same time, we think Magni+ provides compelling reasons that you shouldn’t choose everything simply based on numbers. But seriously, you tell us. 

Why the name “Heretic?”
When we started developing an all-op-amp Magni, it was 100% counter to everything we’ve done. We’ve always done fully discrete designs, when we weren’t so cost-constrained that they weren’t practical. Going op-amp was far, far easier, and more typical in today’s world, but it was, well, almost anathema. So to us, an op-amp Magni was heretical. But we’re happy with the way it turned out!

So which one is powerful enough for inefficient, planar magnetic headphones?
All of them have tons of power—specifically 2.4W RMS per channel at less than 1% THD, though both typically perform comfortably above that.

Why is it a “Magni+” and not a “Magni 4?”
No 4s. Oh no, no 4s. Heck no.

What, are you superstitious or something?
More and more every year.

All right then. What’s this about DC coupling?
All Magnis have no capacitors in the signal path at all—that’s what we mean by DC coupling. This eliminates any sonic effect a capacitor in the signal path might have on your system.

So you probably cheaped out and left the protection off these amps, or something stupid like that, right?
No. In fact, this generation of Magnis has the most advanced protection we’ve ever included in an affordable amp. This includes completely transparent current sensing and overcurrent protection (great when someone accidentally plugs in a TRRS headphone with a wonky adapter) and DC sense and protect, or DC correction, which protects your headphones in the unlikely event of a catastrophic failure.

So I bet you don’t have enough power for hard-to-drive headphones.
With 2.4W RMS per channel (the only real way to rate), you’d lose that bet.

And you’re probably not set for IEMs, either.
With a -10dB negative gain setting, you’d lose that bet too. Fun fact: the -10dB gain setting even decreases the inherent noise floor of Heretic, making it even quieter than quiet (because both Magnis have inaudible noise floors.)

These sound so great! Why would I buy any of your other amps?
Seriously, you really don’t need to. Hence the “no excuses.” But, you know, different people like different things, and they may want to try out tube amps, or balanced amps, or Class A/Continuity™ amps.

I want a combined DAC/amp! Why didn’t you put a DAC in here?
We did. They’re just in a different chassis and costs another $129-249. They’re called “Modi+” or “Modi Multibit 2.” Modi Multibit 2 is on hold for a bit while we wait for parts, sorry for the delay. Hopefully by mid 2023.

Hey, so does that mean I can plug in some uber-special, gold-plated, cryo-treated, 85-lb 2000VA wall wart and have even better performance?
Unless you know what you’re doing, we don’t recommend that. Magni uses an AC wall wart. Most are DC. DC won’t work with either Magni. Plus, seriously? This is an affordable amp. You want to use some $599 power supply with it? Nah.

What the hel is a Magni?
In Norse mythology, Magni was one of Thor’s sons. 

Magni+ and Magni Heretic Manual