HIFIMAN Susvara Headphone Review

[Tano]

Not a single DCA headphone on this self-proclaimed "Best headphones in 2023 / 2024" kek

Best Headphones In 2023 / 2024

Audio: Listen to this article. Best Headphones In 2023 / 2024 By Sajid Amit, Founder, Amplify Audio Reviews. Hi everyone! Just casually dropping my top 10 headphones for 2023, here! There are so many excellent headphones in the world, varying degrees of compatibility with musical genres, user pre...

audiophilestyle.com

I don't like that guy. He is pretty esoteric and loves snake oil, but I can't see how a DCA should be on his list. That's a subjective list. I wouldn't put any DCA on my top 10 either...

 

[chosen1ft]

I noticed that someone has been discussing with you frequently about whether a certain type of noise exists or not. I don't think this is a situation that would occur commonly, otherwise there would be widespread reports worldwide. I have personally listened to these headphones twice. The first time was in a store, where they were driven very well, and I did hear a very lifelike sound. The second time, I rented the headphones home and listened to them for a few days, driven by an A90D. I couldn't hear the lifelike sound anymore, but I also didn't hear any noise. What I am sure of is that even the A90D cannot properly drive the Susvara, which is a very picky headphone. I say this because I will never forget the sound I heard for the first time in the store.

 

[Rhamnetin]

I noticed that someone has been discussing with you frequently about whether a certain type of noise exists or not. I don't think this is a situation that would occur commonly, otherwise there would be widespread reports worldwide. I have personally listened to these headphones twice. The first time was in a store, where they were driven very well, and I did hear a very lifelike sound. The second time, I rented the headphones home and listened to them for a few days, driven by an A90D. I couldn't hear the lifelike sound anymore, but I also didn't hear any noise. What I am sure of is that even the A90D cannot properly drive the Susvara, which is a very picky headphone. I say this because I will never forget the sound I heard for the first time in the store.

The A90D delivered 3.7W into 50 ohm into the review here, the Susvara is 65 ohm so the power would be slightly less. Realistically, no one is running out of volume headroom with the A90D + Susvara combo, and the A90D noise and distortion are state of the art driving such a load while the frequency response is flat. The only amps that perform better than the A90D here are the A70 Pro, and the Benchmark HPA4 in THD+N but not in power, from all the data I can find. I can't imagine you encountered any clipping with the A90D + Susvara.

So it doesn't appear to be a matter of the A90D not being able to properly drive it, as this would mean it clipped or came close - hard to imagine unless you are listening at >114 dB SPL which is insane. But rather you may have preferred something in the other system but whether that was added distortion, unflat FR from the electronics, or something else is anyone's guess. But more importantly, you say you'll never forget that sound in the store, but the fact of the matter is that is unreliable and not something to draw conclusions on. You didn't do a level matched A/B test, let alone a level matched A/B blind test.

 

[chosen1ft]

If the Susvara is really that mediocre, I can't understand why Topping would pair it with their flagship headphone amplifier as a Promotional Image

 

[majingotan]

Topping is showcasing that it can power the notoriously difficult to drive Susvara easily! There’s no better way to describe it to customers that aren’t adept on translating power output into how adequately it drives a headphone

 

[chosen1ft]

Topping is showcasing that it can power the notoriously difficult to drive Susvara easily! There’s no better way to describe it to customers that aren’t adept on translating power output into how adequately it drives a headphone

The HE6SE is also difficult to drive, and it has a higher rating here. Why didn't Topping choose HE6se as a match?

 

[majingotan]

The HE6SE is also difficult to drive, and it has a higher rating here. Why didn't Topping choose HE6se as a match?

Susvara is $6K headphones and the more $$$, the better it sounds to an audiophile in the money pit audio gear market. HE6SE is the “bastardized” version of the 6-screw and 4-screw HE6 and it doesn’t scream TOTL thus have poor reception among audiophiles

 

[majingotan]

@majingotan are you going to sell your Susvara now that it has been debunked? Or are you actually going to continue listening to it because despite this review you actually still sorta like it? It does actually temper the aura and mystique around it for me a bit, but if you wanted to offload it for a bargain price (it's worse tuning than a $25 IEM remember) I might be interested. I need to go on holiday soon actually, we have bad pollution coming up here soon, if the price was good enough I would come get it

If you want my Susvara you’ll have to pry it off from my cold dead hands I won’t hesitate buying another one if it ever stops working on me. Hifiman QC lottery be dammed, I’d wager my hard earned money to buy it again

 

[Rhamnetin]

Also you'd want to showcase your new product with something that's strongly relevant. The Susvara has been the most popular and hyped low sensitivity headphone in recent years. The HE6se wasn't a flagship thus lacked cool factor (the Susvara's looks are a bonus). Not many people know what the Mod House Tungsten is. There aren't many other low sensitivity headphones around at any given time.

 

[chosen1ft]

Also you'd want to showcase your new product with something that's strongly relevant. The Susvara has been the most popular and hyped low sensitivity headphone in recent years. The HE6se wasn't a flagship thus lacked cool factor (the Susvara's looks are a bonus). Not many people know what the Mod House Tungsten is. There aren't many other low sensitivity headphones around at any given time.

Why are low-sensitivity headphones worth hyping instead of being eliminated?It doesn't make any sense。

 

[majingotan]

Why are low-sensitivity headphones worth hyping instead of being eliminated?It doesn't make any sense。

See my post here: https://www.audiosciencereview.com/...n-susvara-headphone-review.50705/post-1822878

 

[Rhamnetin]

See my post here: https://www.audiosciencereview.com/...n-susvara-headphone-review.50705/post-1822878

"Zero feedback", I bet it measures poorly like this other amp of theirs even in solid state mode. I'd also expect the Topping A70 Pro to deliver more power into the Susvara before clipping.

 

[majingotan]

"Zero feedback", I bet it measures poorly like this other amp of theirs even in solid state mode. I'd also expect the Topping A70 Pro to deliver more power into the Susvara before clipping.

That's a given of course.

Speaking of feedbacks, Jason for Schiit posted an essay regarding technical descriptions of feedback:

2024, Chapter 1
The Most Abused Audio Terms, Part 4: Feedback

Let’s start with a mind-blower:

All your audio electronics have feedback.

All of them. Every electronic product you love listening to. Op-amp products. Discrete products. Class A and Class AB and Class D and Class S and H and G…all have feedback.

Even ones labeled “no feedback”…have feedback!

Shocked?

Yeah, I thought you would be.

And I’m sure some of you are saying, “No, wait a minute, I only buy no-feedback products! I know they’re no-feedback because the marketing told me so!”

And some are protesting, “Hold on, you guys make no-feedback products, don’t you?”

And some are wondering, “Why does everything have feedback?”

Simple: Every audio electronic product has feedback because if it doesn’t, it probably sucks so much it isn’t a viable product.

Huh? What?

Has Jason fallen to the cult of measurement?

Has he joined the ranks of feedback maximalists who say feedback is great, lots is better, and mostest is bestest?

In short, no.

It’s just that feedback is a complex subject. It has real pluses and real minuses and lots of gray area in implementation. And because it’s complex and misused, it’s gotten a bit of a stink in some circles—specifically, among some audiophiles who think All Feedback is Bad…and, at the same time, it has been portayed as the One True Savior in other corners of audiodom, most particularly amongst some designers who have stated, pretty much, “you can never have too much feedback!”

How can feedback be vilified and celebrated at the same time? And why is the best use of it somewhere in that scary hard-to-define middle?

And what about all this about everything having feedback? That can’t be true, can it?

Well, let’s first back up and define feedback, for the guys out there who are shaking their heads and saying, “What are all these nerds talking about?”


Feedback 101

Want to make a signal bigger?

Of course you do. Whether you’re starting with 0.5mV (5/10,000 of a volt) from a MC cartridge or 2V from a DAC, you need a whole lot more gain to drive a speaker—gain in terms of both voltage and current.

So you want an audio amplifier.

Now, when we’re designing this audio amplifier, we can choose to use a whole lot of different discrete amplification devices: BJTs (“transistors”), JFETs, MOSFETs, tubes, etc. And, if the current requirements are small, you could even choose an integrated circuit, an op-amp.

The problem is: every amplification device is nonlinear.

As in, it’s not a perfect “valve.” So it will create distortion. And noise. And it most likely will have too much gain to be usable. It may not even have enough bandwidth to cover the full audio band.

In audio, negative feedback is a way of trading gain for linearity.

Apply negative feedback, and you get:

• Higher bandwidth
• Lower distortion
• Lower noise
• Lower output impedance

And most amplification devices have plenty of gain to trade. Op-amps can have 100-130dB of gain open-loop. (And with an open-loop bandwidth of 10-100Hz, oh boy they need to trade.) A simple single-transistor undegenerated circuit can have 40dB of gain. A 2-stage discrete amp can have 60-80dB of gain.

Aaannndd…you really can’t use that much gain. So trading some of it sounds like it makes a lot of sense. But there are some gotchas, which we’ll get to later.

Negative feedback has been likened to “comparing the input and the output,” which calls to mind weird electronic structures that exist outside of the amplifier, considering it with cool and calculating eyes like Well’s Martians.

In reality, negative feedback is inherently part of the circuit. There’s no invisible arbiters existing outside of the Holy Topology. The topology itself contains the feedback.

Feedback In classic control systems, it looks like this.

Or, in a simple circuit (op-amp), it looks like this:

In a discrete design, it can look like this:

“Huh? Wait a sec!” some of you cry. I don’t see the feedback here. Where’s the feedback?”

Gotcha. There are actually several types of feedback being used in that diagram…and it can still be labeled “no feedback” for the purpose of marketing.

Mind blown?

Cool. Let's deconstruct this.


Stayin’ Local

The first two diagrams above show negative feedback being applied to an entire circuit. The feedback loop goes from the system output back to the input, encompassing the entire topology.

This is known as “overall negative feedback.”

And, when amplifiers claim “no feedback” or “zero feedback,” this is what they mean:

There’s no overall feedback from the output all the way back to the input.

“Oh hell wait a sec you can have feedback buried inside an amp?” you yell. “Feedback that's feedback but you call it no feedfback? That’s sneaky AF!”

Well, yes and no.

Yes, you can have feedback inside an amp topology—local feedback. There are many kinds of local feedback, from degeneration to local loops to complementary pairs and more. All practical amplifiers, especially no-feedback amps, will have local feedback.

But no, it’s not sneaky. Local feedback is usually necessary to make an amplifier really usable—as in, with high enough linearity and low enough gain that it’s a real product that effectively provides the gain and performance you need.

Without local feedback, and without an overall feedback loop, an audio power amp might have 60-80dB of gain. That’s 1,000-10,000x gain. No matter how loud you listen, or how much you love the opening scene of Back to the Future, that’s wayyyyyyyyy tooooo much gain.

So, internally, you trade some gain for linearity with local feedback…

…and then you can choose to have an overall feedback loop as well.

Let’s look at some of the local feedback options:

Degeneration:

Sounds horrible, doesn’t it? “You degenerate! How dare you use degeneration!”

In reality, this is probably the most commonly used form of feedback, and one that has pretty much 100% positive effects. Both Doug Self and Bob Cordell have written extensively about degeneration and its benefits. In short, it:

• Reduces the gain of the first stage of an amplifier
• Increases the linearity of that same first stage
• Compensates for variability in discrete devices

Degeneration is used in all of our products. And, I’ll bet it’s used in every product labeled “no feedback” as well, because it’s a great way to enhance performance with really no downsides.

“Wait a sec,” someone says. “Is that really feedback?”

In short, yes, this is really feedback. It meets all the criteria for feedback. It is just so localized that it doesn’t look like feedback. And it is so necessary—especially in amps with no overall feedback—that it’s used pretty much everywhere.

Or, in other words: yes, Virginia, your no-feedback amp has feedback.

Re: (No Boom):

Like those resistors in the output stage? They’re doing something similar to degeneration in the input stage—they’re compensating for variations in the output devices (sorry, guys, discrete devices do vary…simulators beware), and they’re usually providing some degree of thermal stability as well.

Also usually found in no-feedback power amps. But yeah, still feedback.

Thermal Stability (Also No Boom):

Oh this is a weird one, right? Yeah, these resistors aren’t technically needed in a diamond buffer, but try getting by without them. You may find it goes up in smoke due to thermal runaway. A different kind of feedback, but still feedback.

And, by the way, current feedback amps like Vidar, Magni, etc absolutely depend on these resistors.

Complementary Pairs:

This is one of my favorites.

Complementary pairs, or Complementary Feedback Pairs, are one of the best ways to get a simple, high-performance circuit from very few discrete components.

• Pair an NPN and PNP transistor, and suddenly you have a much higher-performance device.
• Stack two transistors (BJT, JFET, MOSFET) on top of each other with one acting as a current source, and suddenly the distortion cancels, creating a much higher-performance device.

Heck, a 2-transistor buffer can reach -116-118dB THD+N into light loads. That’s 2 transistors, 2 resistors. Near state of the art performance. No feedback! (LOL)

Local Loops:

Looks like overall feedback, but not overall, right?

Exactly. It’s a negative feedback loop that doesn’t go all the way to the output. Very common in “no feedback” amps, though I’d consider this one kinda sneaky if it went all the way to the drivers, as in this example.

This kind of local loop is super-useful, especially with complex amplifiers that may need some additional compensation options.

“Compensation?” you ask.

Yeah, more on that later, in the downsides of feedback.

Error Correction:

Another local loop, this time around the output stage—and, oh yeah, not technically feedback.

This is error correction, or feedforward, as the breathless pundits told us was the One True Path circa 2016 or so. Actually, this is Hawksford error correction, which predates the pundits of 2018 by about 30 years.

Aaaaaand…for additional confusion, this is not technically feedback.

The equations are totally different. It’s not feeding back the entire signal, it’s feeding back only the difference between input and output.

This is a great one for a no-overall-feedback amp, because it can be both no-feedback AND have low output impedance.

DC Servo:

Another fun one: feedback only at very low frequencies.

Why would someone want to do that? To eliminate DC at the output of an amplifier, without trimming (and possible drift over time) or coupling capacitors. DC servos are widely used to both eliminate DC, and provide correction for input DC, in DC-coupled amps.

Is it feedback? Absolutely. Can it be used in a “no-feedback” amp? Also absolutely.

So is that it for sneaky feedback?

Oh no, there are tons of other techniques. Get Bob Cordell’s book and look into his chapter on how to create a no-overall-feedback amplifier, and he’ll get into much more detail, including stuff like instrumentation front ends.

And, here’s the thing to keep in mind: You can use every single one of these local techniques in an amp—and still claim “no feedback!”

Because what you really mean is “no overall feedback,” and that can be absolutely true.

But even in overall feedback, there are flavors.

Let’s talk about two of them.


Current vs Voltage

You may have heard of amps billed as “current feedback” amplifiers. Heck, you’ve heard it from us, because the vast majority of amps we do are current feedback.

Current feedback is kinda weird, though. Most of the amplifiers on the planet—discrete or op-amp—are voltage feedback amps.

Why?

I can be snarky and say, “Well, it’s because the Lin topology, which evolved into Blameless, and is used as the foundation for pretty much every amp you see in every audio power amp book, is voltage feedback, and so most people start with voltage feedback, it’s what they know, why try anything else, and there you go you have all phones as rounded rectangles and you have pretty much all amps as voltage feedback.”

But it’s more than that. Voltage feedback and current feedback both have their pluses and minuses, and so they both have their place in the world. In brief:

Voltage feedback:

Advantages:

• More gain—allows for more feedback and better numbers
• Higher power supply rejection—you can have a noisier power supply and it will ignore it better
• High impedance negative input terminal means easy overall negative feedback

Disadvantages:

• Lower bandwidth—not affected by feedback
• Slower slew rate, dominated by how much current available to drive Miller capacitance
• More prone to asymmetric slew and ringing—more difficult to compensate

Fun fact: the diagram above also shows nested loops--a local loop inside an overall loop.

Current feedback:

Advantages:

• Higher bandwidth—can be “tuned” with feedback
• Faster slew rate, not affected by front end current
• Very easy to compensate

Disadvantages:

• Lower gain—lower feedback and worse THD numbers
• Lower power supply rejection—getting good PSRR is more work
• Low impedance feedback terminal

In general, a voltage feedback amp will do better in terms of both THD and noise, which shouldn’t be surprising because it has more gain and can use more feedback. This shouldn’t be a surprise, because it has two stages of voltage gain, versus the single stage of a current feedback amp.

Aside: it’s amazing Magni Unity does as well as it does, given the inherent disadvantages of a current feedback amp. It’s uncomfortably close to state of the art measurements, with 100dB less feedback.

So why stick with current feedback when voltage feedback gives better numbers?

In some applications, it’s a matter of speed—rise time needs to be faster than practical for voltage feedback. But these are extreme applications, not audio. In audio, the choice of current feedback is a more personalized one.

“Well, hey you said you like current feedback better because it sounds better,” someone says. And yes, that’s my personal opinion. It’s also the result of much internal blind listening (yes, double-blind, yes, level-matched, no, not DBX, no, not worthy of MIT-level publication).

In addition, we also like the overall simplicity of current feedback, the lack of excessive gain, and its easy-to-compensate nature. Anyone who’s fought with an unstable voltage feedback amp knows exactly what I’m talking about.

Which is a great segue, because I’m sure more than a few of you have been wondering:

“Why all this talk of negative feedback? Is there positive feedback?”

Well, yes, but you don’t want it. Positive feedback creates an oscillator. As in, a circuit that produces a single frequency constantly, forever, as soon as you turn it on. Sometimes this is a good thing—you may want an oscillator to produce a sine at a particular frequency.

Most of the time, it is a bad thing. Heck, you know it’s a bad thing if you’ve ever grabbed the mic of an old-skool PA system and had it shriek you out of the auditorium. That’s positive feedback.

And it’s a very very bad thing if you’re talking about a power amp that can source tens of amps that is suddenly oscillating full scale and torching itself and the speakers it’s connected to.

Huh? What do I mean? And why is this a good segue?

It’s a good segue because compensating amps is all about making sure their open-loop gain goes below 1 by the time the output phase shift has reached 180 degrees.

Huh?

Okay, let's see if we can explain this without math:

• Negative feedback: feedback that’s inverted, or 180 degrees out of phase, with the input signal. This subtracts from the input. Safe.
• Positive feedback: feedback that’s in phase with the input signal, or 0 degrees out of phase. This adds to the input. No bueno.

Now, all amps have phase shift, and the phase shift increases with frequency. So your negative feedback, that safe 180-degrees-out-of-phase feedback, slowly changes. At 10kHz, it might be 160 degrees off. At 100kHz, it might be 90 degrees. At 1MHz, it might be 0.

And, if the amp has positive gain (more than a gain of 1) at 1MHz, it suddenly becomes a power oscillator and things go bang.

So, you compensate the amp (manage poles and zeroes, or, in English, place compensation capacitors at strategic places), in order to ensure the amp never has positive gain when phase shift has turned it into a potential oscillator.

With a voltage feedback amp, it’s not unusual to have complex and nested compensation with half a dozen capacitors or capacitors and resistor combos to get it stable. That previously-mentioned Magni Unity? One capacitor. Done.

Yeah, we like current feedback.

But voltage feedback (and no overall feedback) also have their place.


Feedback Gotchas and Best Practices

Now, some of you aren’t happy. You’re crossing your arms and saying, “You said there were pros and cons to feedback. You’ve talked about the pros. And you’ve talked about the kinds of feedback. What about the cons? What’s the catch?”

Yep yep, I hear you. So here are the catches when you use feedback:

• Gain and phase margin are now critical. Amplifier stability is now something you have to pay much, much more attention to if you want to have a solid, reliable, versatile product.
• Transient response can suffer. Even if you have a stable amplifier, it may still ring, or, in engineering terms, exhibit underdamped characteristics.
• Compensation may entail trade-offs between gain and phase margin and transient response. You want a stable amplifier, and you’d like it to have rapid rise times, but sometimes not all of those are in the cards.
• Using too little feedback can cause different kinds of distortion that aren’t pleasant—re-entrant distortion. To be honest, this isn’t common.
• Using too much feedback can mask problems with the open-loop circuit that should be fixed, like running too low of a Class AB bias.
• On some monumentally slow circuits, feedback can cause transient distortion that is also very unpleasant. This is, like re-entrant distortion, not super common.
• The more complex the feedback, the more difficult it is to get the amplifier stable. Imagine an amp with local loops, a global loop, and error correction. That’s a lot of complexity to manage.

But these are just the technical catches. One of the biggest catches is that, simply, feedback is considered by some to be undesirable. They say things like “Feedback squashes dynamics, amps with feedback sound lifeless,” and “no feedback is the only way to go.”

However, at the same time, feedback is considered by others to be a 100% positive thing. “There’s no such thing as too much feedback,” they say. “More feedback is better, and most is best.”

Yes. There are Feedback Minimalists and Feedback Maximalists.

In reality, both oversimplify. At least in my opinion.

Feedback Minimalists sometimes don't:

• Acknowledge that “no feedback” amps actually contain plenty of feedback
• Realize that “no overall feedback” is really what these amps are
• Understand that making an amp with low output impedance usually requires some loop feedback—or will be very expensive because it will need many paralleled output devices
• Learn that types of feedback may matter—it’s not one size fits all
• Accept that there’s a place for feedback, properly used

Feedback Maximalists sometimes need to:

• Be honest about their assertions: “more feedback is better for better measurements” is typically what they mean
• Acknowledge what feedback might be hiding—nonlinearities in the overall circuit or topology
• Provide enough information about transient performance to assure the negative effects of feedback are managed
• Understand that low- and no-overall-feedback amps can get very close to, or even exceed, the measured performance of high-feedback designs
• Accept that there are other ideologies in audio amplifier design

“So what does Jason think?” someone asks.

Sigh.

As usual, I’m gonna irritate everyone.

Because I think both the drive to zero feedback and the drive to maximum feedback are both a bit bonkers. Both oversimplify the problem.

With zero overall feedback, and minimal local feedback (no large local loops, for instance), it’s very difficult to produce a usable amplifier with decent measurements and low output impedance, at least not without having it cost a beeeeeelion dollars because you have to use 32 paralleled pairs of output devices per channel.

At the same time, with the maximum amount of feedback to aim at the maximum measurements, it’s going to be realllly tempting to do everything you can to get more gain, even if it sacrifices open-loop linearity, and it’s gonna be reaaallly reallllllly tempting to use every feedback technique—local, error correction, nested, and overall—to really get those numbers.

My approach is in the middle:

• Make the open-loop gain stage as linear as possible. This will include degeneration, and, at times, compound pairs or cascoding.
• Use as little overall feedback as possible to reach the design goals. Most of our stuff has 6-30dB of overall feedback. Some have zero. But zero is not a goal in itself.
• Consider local loops and nested loops for difficult topologies. As things get more complex, and power output increases, local or nested loops can improve performance.

Some devices deviate quite a bit from this template—see the appendix below—but that’s the general idea.


Feedback on Feedback: The Good, Bad, and Ugly

I opened this chapter as “The Most Abused Audio Terms, Part 4.”

And “feedback” is certainly abused—usually as in an implication that it’s something best avoided.

In fact, “no feedback” has become a badge of honor amongst some, but as discussed above, it’s really an oversimplification. All audio amplifiers contain some forms of feedback. “No feedback” usually refers only to the lack of overall loop feedback.

Aside: I mean, heck, Magni Heresy and Magni Heretic both qualify as “no overall feedback” amplifiers, but considering the 120dB of feedback in the local voltage gain loop and 130dB in the local output buffers, calling it “no feedback” seemed beyond the pale.

So, yeah. “No feedback,” when seen as a marketing claim, should immediately raise some questions.

• Do they mean “no overall feedback?” Usually yes, but it’s worth asking about.
• Do they mean “no overall feedback, and we try to limit the amount of feedback used, because we’re really most interested in creating very linear gain stages that don’t need a lot of feedback,” because, again, that’s frequently what they’re trying to say.
• Or do they mean, “Yeah, this is a pure tube amplifier that doesn’t use degeneration and has bypassed cathodes so technically it’s running full-out, full-gain, all the device can give, because we need it for a phono stage, oh yeah and by the way you better get used to matching these tubes really close, because gain variance will be a real thing, but hey if you really want no feedback we’re as close as you can get, enjoy,” because yeah, maybe that’s a thing too. I haven’t seen it personally, but who knows? Audio is a wonderful space, full of designers with different ideas.

The reality is that feedback isn’t something that should be considered 100% “good” or 100% “bad.” There are great amps with feedback and terrible amps with no feedback.

“So tons and tons of feedback is the ugly,” somebody says, referencing the title of this section.

Well…not necessarily. You may want something with very high loop gain and a lot of feedback—an op-amp—as the error amplifier on a multiplying DAC. Or you may need the same kind of device due to limited design size or power dissipation. Those devices may perform very well in those applications.

No. The only ugly is insisting that there’s One True Path.

The reality is that feedback isn’t evil. It’s very, very useful. It’s everywhere. And it’s usually required for a truly great product, even if it is “only” local.

The other reality is that moar and more feedback isn’t the singular answer either. It can hide real problems and promote numbers-chasing that doesn’t really advance the state of the art.

The real challenge is figuring out which type of feedback to use where—and how to use it best. At least that’s how I see it. But, as I’ve said before: I may be crazy!

I hope you enjoyed this foray into feedback!

 

[Blorg]

Why are low-sensitivity headphones worth hyping instead of being eliminated?It doesn't make any sense。

What's the point of Topping making headphone amps with ridiculous power levels, if it's not to drive low-sensitivity headphones exactly like this? It makes perfect sense they'd advertise it with the likes of the Susvara. A70 Pro spec is 17W@16Ω, 6W@64Ω... what do you need those sorts of power levels for if it's not extremely low-sensitivity headphones. I would imagine this is way overkill "even for the Susvara".

Hifiman, I believe, recommend 2W@60Ω and it probably does need about that, I have the HE6SEV2 which is same impedance/sensitivity and I think that is about what it needs, but not crazy anything. In the past, there weren't really powerful headphone amps, so people used speaker amps... and then people got funny ideas and start chasing these ridiculous levels of power.

But there is a feedback loop there, if you aren't looking to power one of these ridiculously low sensitivity headphones, why would you buy one of the Toppings with ludicrous power levels? I have the A90 myself, and I justified that to myself "for the HE6SEV2". Because 99% of headphones don't need anywhere near these sorts of power levels and if so, why wouldn't you just buy a $149 Topping L30II (which has even better SINAD and still has 3.4W @32Ω, which is itself pretty ridiculous for 99% of headphones).

 

[alpha_logic]

$60 dollar pair of headphones is a runaway bestseller at $6000 dollars in the world of high end audio. Yeah, sounds about right : )

 

[chosen1ft]

What's the point of Topping making headphone amps with ridiculous power levels, if it's not to drive low-sensitivity headphones exactly like this? It makes perfect sense they'd advertise it with the likes of the Susvara. A70 Pro spec is 17W@16Ω, 6W@64Ω... what do you need those sorts of power levels for if it's not extremely low-sensitivity headphones. I would imagine this is way overkill "even for the Susvara".

Hifiman, I believe, recommend 2W@60Ω and it probably does need about that, I have the HE6SEV2 which is same impedance/sensitivity and I think that is about what it needs, but not crazy anything. In the past, there weren't really powerful headphone amps, so people used speaker amps... and then people got funny ideas and start chasing these ridiculous levels of power.

But there is a feedback loop there, if you aren't looking to power one of these ridiculously low sensitivity headphones, why would you buy one of the Toppings with ludicrous power levels? I have the A90 myself, and I justified that to myself "for the HE6SEV2". Because 99% of headphones don't need anywhere near these sorts of power levels and if so, why wouldn't you just buy a $149 Topping L30II (which has even better SINAD and still has 3.4W @32Ω, which is itself pretty ridiculous for 99% of headphones).

This is what I want to express. It is precisely because these headphones have good sound quality but are difficult to drive that Topping has created such powerful amplifiers. No one would go to such trouble to create such an amplifier for a regular sounding headphone. If they need to use a power amplifier to drive a headphone, it proves that the headphone's sound quality is worth it rather than wasting the electricity.

 

[IAtaman]

Not a single DCA headphone on this self-proclaimed "Best headphones in 2023 / 2024" kek

Best Headphones In 2023 / 2024

Audio: Listen to this article. Best Headphones In 2023 / 2024 By Sajid Amit, Founder, Amplify Audio Reviews. Hi everyone! Just casually dropping my top 10 headphones for 2023, here! There are so many excellent headphones in the world, varying degrees of compatibility with musical genres, user pre...

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What a large pile of crap.

I mean it's obviously a subjective ranking, he says it's subjective if you read his post. Not everyone in the headphone hobby thinks you can rank headphones totally objectively. Even many people who do believe in objective measurements, many here are more sceptical of this with regard to headphones than amps or DACs. It's possible to enjoy different tunings, Crinacle who you referenced obviously believes in measurements and he does tend to prefer something like Harman in headphones, or IEF neutral+bass with IEMs, which is very similar to Harman. But his rankings of headphones or IEMs, he attempts to rank tonality not on compliance to a single target but rather how well it implements the tuning it's going for. So there is a variety of stuff there too.

Well, why then bother to break it down to Tonal and Technical scores and combine them into an overall score to create the perception that those numbers actually mean something?

he attempts to rank tonality not on compliance to a single target but rather how well it implements the tuning it's going for

Yeah okay, I don't know what you think, but I think this is the seal of BS for me

@Rhamnetin

Crinacle's ranking looks more consistent to me. Looking through it, headphones with very similar tonality (especially those from the same brand with more similar characteristics in general) tend to rank more closely with one another. Susvara is right next to the HE1000v2, which is very close to the HE1000se.

Utopia (left) is clearly bass tilted and Susvara (right) is clearly treble tilted. How can both of these be Neutral like HD600 which is actually flat?

Focal Clear (below) is same or even "less" bass tilted than Utopia, but Utopia is "Neutral" and Clear is "Warm"? Makes no sense.

I mean sure, you might not want to stick to a target, but at least some consistency should be expected as minimum in my opinion. And, if you are going to claim neutrality, you need to stick to the research I believe.

 

[Grobbelboy]

This is what I want to express. It is precisely because these headphones have good sound quality but are difficult to drive that Topping has created such powerful amplifiers. No one would go to such trouble to create such an amplifier for a regular sounding headphone. If they need to use a power amplifier to drive a headphone, it proves that the headphone's sound quality is worth it rather than wasting the electricity.

This makes no sense at all. You're just throwing "sound quality" in there for no reason. It's all about the Susvara's popularity among audiophiles and its hard-to-drive notoriety, sound quality isn't a factor in any of this.

 

[Blorg]

@IAtaman Clear is more recessed in the upper mids/treble than the Utopia, certainly subjectively the Utopia sounds brighter. You can see that in Oratory's graph though. Just about anyone who listens to them, will think the Utopia sounds brighter. It's there in Crinacle's measurements as well. Worth noting the worn pads on the Clear but he can only give an opinion on what he heard. I have both of them as well, the Utopia is definitely brighter sounding.

It's actually even more evident in Oratory's graph than Crinacle's.

Oratory's measurement of the Susvara is a bit anomalous, most measurements of it don't have that size of peak over Harman in the upper mids. Most other Hifimans do; the Susvara is the one that is less forward and more neutrally tuned in that region. And most other measurements do show this, including Amir's.

Crinacle, I'm including the contrast with the Arya which is up in that region:

So Oratory has a peak above Harman, everyone else has inline or Amir even a little below Harman. It's not just the scale or normalization either, if you count the dBs, Oratory does have a far larger peak there than is seen in other measurements of the Susvara. Knock that down and Susvara is looking pretty neutral. Compared with HD600 using IEF neutral (flat bass):

You can put far too much faith in a single set of measurements, there is a lot of variability in graphs depending on who measured, seating, and so on. I think it was Oratory who gave an example just of the range of his own measurement, of one headphone, huge variations are possible.

That exact sort of bump in the upper mids, I've seen in a lot of Oratory's measurements, it seems to be something about his setup that tends to emphasise that region. He's clearly the outlier here, but you take his one measurement as gospel to discredit other's subjective impressions, when most other measurements (including Amir, who must surely be closest to measurement Jesus round these here parts) show a different picture. This is not "scientific".

Graphs are a very useful tool, but you can't just take a single graph of one seating of one unit and pronounce that's the absolute truth about a headphone... particularly if you've never heard it. I haven't heard the Susvara, I do have 9-10 other Hifimans and both Clear and Utopia.

 

[IAtaman]

@IAtaman Clear is more recessed in the upper mids/treble than the Utopia, certainly subjectively the Utopia sounds brighter. You can see that in Oratory's graph though. Just about anyone who listens to them, will think the Utopia sounds brighter. It's there in Crinacle's measurements as well. Worth noting the worn pads on the Clear but he can only give an opinion on what he heard. I have both of them as well, the Utopia is definitely brighter sounding.

View attachment 341386

It's actually even more evident in Oratory's graph than Crinacle's.

Oratory's measurement of the Susvara is a bit anomalous, most measurements of it don't have that size of peak over Harman in the upper mids. Most other Hifimans do; the Susvara is the one that is less forward and more neutrally tuned in that region. And most other measurements do show this, including Amir's.

Crinacle, I'm including the contrast with the Arya which is up in that region:

View attachment 341387View attachment 341388
View attachment 341390View attachment 341389

So Oratory has a peak above Harman, everyone else has inline or Amir even a little below Harman. It's not just the scale or normalization either, if you count the dBs, Oratory does have a far larger peak there than is seen in other measurements of the Susvara. Knock that down and Susvara is looking pretty neutral. Compared with HD600 using IEF neutral (flat bass):
View attachment 341391

You can put far too much faith in a single set of measurements, there is a lot of variability in graphs depending on who measured, seating, and so on. I think it was Oratory who gave an example just of the range of his own measurement, of one headphone, huge variations are possible.

That exact sort of bump in the upper mids, I've seen in a lot of Oratory's measurements, it seems to be something about his setup that tends to emphasise that region. He's clearly the outlier here, but you take his one measurement as gospel to discredit other's subjective impressions, when most other measurements (including Amir, who must surely be closest to measurement Jesus round these here parts) show a different picture. This is not "scientific".

Graphs are a very useful tool, but you can't just take a single graph of one seating of one unit and pronounce that's the absolute truth about a headphone... particularly if you've never heard it. I haven't heard the Susvara, I do have 9-10 other Hifimans and both Clear and Utopia.

You are making fair points, some of which I agree. For some others, I have counter points

For Clear and Utopia, I have not heard either of them and I am happy to accept your impressions.

For Hifimans, I have a different view.

I don't think it is a good idea to try and judge tonal balance by eye from the graphs. The reason I refer to Oratory's measurements is because he does calculate the tilt of the error curve which is a good indication of overall tonal balance. Amir's measurements seem to be presenting a less bright picture indeed, but I think that is because of the normalization frequency Amir uses (450Hz I think) compared to that of Oratory. If you take Amir's measurement data and calculate the slope of the error curve (which I did), you'll find that Susvara is bright tilted as per Amir's data too (although admittedly, not as much)

Tilt of the error curve is a more reliable metric, because it is not affected by the normalization frequency chosen (I think).

On the more subjective side, I did hear Susvara. I don't own it, so I can not compare back and forth directly, but I heard it same time I heard Arya and HE1000v2 both of which I own, and can compare to HD600. There is no way in my opinion that both HD600 and HE1000v2 can be both called Neutral. If HD600 is neutral than HE1000V2 isn't and vice versa.

Look at the tilt of the error curve for HE1000v2 above. Mind you, that is calculated from 50Hz to 10K. If you take the full range into account, which you would if you are evaluating subjectively, that would be even more treble titled.

Compare that to the tilt of error of HD600. Flat as a ruler (almost).

How can both these headphones be Neutral?