Do I need an amp? How much power do headphones ACTUALLY need? - Myths about power

Do you need an amplifier? How much power do you really need? And what misconceptions exist about hard to drive headphones in general?
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0:00 - Intro
0:43 - Headphone specs
1:40 - How much power do I need?
4:09 - Myth 1: High Impedance = Hard to Drive
5:13 - Myth 2: Volume knob indicates headroom
7:04 - Myth 3: I need lots of power
7:45 - Myth 4: High powered amps are better at low power than low powered amps
9:59 - Myth 5: Class A watts are better than others

[@brockercheddlie]

would love a vid of an explanation of the differences between class a, a/b, d amps

[@Bhatakti_Hawas]

Yes plz

[@NexusS4GIceJelly]

Only Class A amp that I consider as 100.00000% Class A is a pure single ended triode (no parallel tubes, directly or indirectly heated or triode strapped without any option to switch to pentode) output transformer coupled amp. The rest of them that claim Class A are not Class A in my book since they have tricks to switch to A/B when power requirements increases beyond a certain point or has a push-pull /pentode/ultra-linear mode, or it's a balanced driven triode amp).

[@williamsteven5613]

​@@NexusS4GIceJelly why does it being single ended matter?

[@NexusS4GIceJelly]

@@williamsteven5613 A balanced amp uses push-pull which is Class A/B because each op-amp or tube or transistor only amplifies one set of peaks (positve amplitude peaks for example or R+/L+) and that other tube / op-amp / transistor that amplfies the negative peaks (R-/L-) is momentarily off (50% duty cycle). Manufacturers add something called "Class A Bias" and claim that at a certain power requirements, these transistors can turn on 100% of the time (aka 100% duty cycle) thus amplifying all signals (one tube is R+/R-, complete sine wave in pure Class A) while the other tube/op amp etc amplifies the L+/L-

[@billywindsock9597]

Easy, a, a-b sound different and interesting, d is dull shite. Bit of an overarching generalisation, but an opinion nonetheless.

[@Kuzushi42]

I'd like to see a video on how using an amp vs not using one affects the sound quality of headphones, i.e. what things can I look for to know whether my headphones are underpowered, or how much performance am I leaving on the table by not using an amp on a headphone that is supposedly hard to drive.

[@ManoharSingh-dg8ih]

My phone could only derive DT 770 pro at say around low-half volume, where as Macbook pro was able to derive it to very high volume. As for quality of sound it doesn't change, maybe loudness effect can appear like a change.

[@Phoenix_of_the]

how many ohms @@ManoharSingh-dg8ih

[@ManoharSingh-dg8ih]

@@Phoenix_of_the 80

[@alondite215]

@@ManoharSingh-dg8ih This is flat-out wrong. Rarely is an amp actually required to get adequate listening volumes, the reason you amp is to supply adequate power to properly control the driver through any dynamic swing you may throw at it. A properly-amped driver is faster, more dynamic, detailed, and more controlled as a whole.

[@Lishtenbird]

I'd like the topic of balanced cables for headphones explored in a similar way.

[@maidsandmuses]

There are a lot of myths surrounding the use of balanced cables with headphones, not helped by the different cable topologies different brands headphones have, and whether the headphones are passive transducers or an active (e.g. noise-cancelling) one. For "traditional" topologies where each L/R capsule has its own 2-core cable feed and the "grounds" are tied together at the headphone jack end of the cable, if switching to a balanced cable results in an audible difference that means there is something wrong with the grounding topology and/or termination inside the non-balanced headphone amp. A passive headphone itself (excl. cable) is by definition a balanced device as both "ground" and "live" feeds terminate in the same impedance.

[@maestherc]

Very succinct, very clear and very *needed* tutorial on this subject. I design vacuum tube amplification gear professionally, and the subject matter you cover here is *very* commonly misunderstood by audio enthusiasts. Kudos!

[@ranelime]

I really enjoy your thorough descriptions. You have a way of delivering lots of information in an entertaining way!

[@dangerzone007]

Also you should have mentioned that the impedance of dynamic headphones varies significantly with frequency.

[@GoldenSound]

Yep! This is also an important factor to consider

[@blainelacross5311]

Although it's worth noting that the nominal impedance should be near to the lowest impedance, so that variation in impedance can only make for LESS power draw at some frequencies. For more power to be drawn from a voltage source, impedance must fall (which does happen in some IEMs), and technically the standard is that headphone impedance is "supposed" to be specified at or near the very lowest impedance.

[@markrussellsmith]

There are certainly a lot of misconceptions about this.

[@Joelsfilmer]

@@GoldenSound But since the impedance bump of dynamic drivers are at the same place as the resonance frequency, the power required ends up at plus/minus zero, right?

[@HifiSammy]

Great video. I appreciate your vids and how you cover these topics. You somehow manage to keep it simple while hitting all of the important tech points that we need to understand. Thank you Golden Sound!

[@davidwright2379]

This has to be one of the best videos explaining the spl and amp power requirements I've seen for quite some time, extremely informative and detailed, thankyou, my btr5 dac amp no worries with a 300 ohm drop 6xx or sennheiser 650, cheers mate.

[@richardshevkun7871]

I've been waiting for such a vid to spread around for an eternity. Tanks a lot

[@nunyabusiness3612]

Brilliant as always Cameron, thank you. That was such a clear and succinct explanation of the matter at hand.

[@sy0635]

Wow this video was extremely helpful thank you. More people and reviewers need to see this. Alot more misconceptions about amps out there than I thought.

[@Jack-di6rc]

This is super insightful even for someone who has been in the hobby for 5 years. Thank you golden.

[@joolibreakingmore]

Love every video with goldensound! Such great explanations. Could you explore the topic of what constitutes a well mastered song, and how best to music songs for testing headphones?

[@knightwolf200612]

Very nice, excellent explanation of all power details! Exactly what I needed to know. Thanks!

[@giorgosapo4508]

Amazing video and wonderful analysis/explanation 😁

[@Tarnith]

So many people get tripped up on impedance != efficiency and more refers to voltage vs current driving. This is a great video to send to most people asking about headphones, succinct overview and hits all the main points really well. Cheers.

[@guillermoleoni]

Thank you, it is the clearest explanation on this subject that I have seen!

[@desking8683]

Thanks, that was a knowledgeable and succinct presentation. Very well done! Am wondering if a presentation on this topic with a small assortment of amps and headphones would be appropriate for events such as CanJam or other HiFi shows? There is nothing quite like personally engaging in the points mentioned, (watts, impedance and sensitivity), than through first hand experience for those new to the hobby that is a passion for many. Really enjoy the conversations between and collaborative attitude of the people on The Headphone Show.

[@CostaBatis]

Great info, thank you! Keep up the good work!

[@dl88889]

Great video. Im a beginner and you taught me everything I needed to get my first dac amp. Thank you!

[@force330]

Excellent video! I learn more really. Thanks team!!

[@Buddythunder1]

Excellent vid! I've been vaguely concerned that my 2W Bottlehead amp might be under-driving my HE6SE's. They sound lovely to me though and the amp is easily able to power them beyond comfort-level. With a more nuanced view of power, I now see I needn't have worried.

[@easygoingdude9990]

This was extremely helpful thank you!

[@chrispapa6700]

Very informative video great job.

[@deadline7610]

Nicely Done. Since your asking. How about a video taking tier groups of iems & headphone (well known ) priced from $50- & up and pair them with a dac/amp price appropriate for that specific gear. Showing how an inexpensive stack will handle the iem or headphone just fine and what a tier up in price offers :) Including the info. from this video and the power calculator :) Thanks

[@kellustzall3057]

100% informative goodness I need in my life

[@BobbyDigital6411]

Extremely informative video!

[@peergynt6515]

This helped me a lot, thanks!

[@GadZookz]

Very enlightening video. Thanks! If you were a headphone amplifier, which one would you be?

[@dm41nman64]

Wow! Thank you so much @goldensound and @HeadphoneShow for this more straightforward approach and explanation, another added knowledge.

[@gdemirjian]

Great video, Cameron. I use a digital db meter ($20 Amazon) and shoot for 80-85db at abut 50-60% amp volume at low gain setting (I typically only use high gain for a little more note weight at low listening levels, like the old-fashioned loudness function). After doing this with about a dozen sources I have gotten to know my headphone driving need rather well. Now I can more easily look at the impedance and sensitivity of a headphone and basically know the ballpark power source needed.

[@koustuvkanungo9873]

Just pointing a db meter at a headphone cup isn't a good measure of their SPL, you'll end up underestimating it by a lot.

[@dukdive]

He also literally said % of amp volume is doing it wrong

[@gdemirjian]

@@koustuvkanungo9873 the meter tip inserts between the pads as I press them to seal around the meter tip. It is not meant to be scientific measure. I use this for benchmarking. Very useful to protect me ears too. Thanks.

[@gdemirjian]

@@dukdive Cameron's method is more accurate but my method is a quick way within an acceptable SD to benchmark my listening levels for understanding my headphones power needs and to protect my ears. Thanks.

[@fishinthejar]

This was a topic that needed a good video, and ggood this video is. Thank Golden, good shit!

[@barashkaz]

Wonderful video, thank you.

[@1337sim1]

Great video ! 👏This is what everybody should watch before buying an headphone amp!

[@mrfarax4944]

Lovely video great info, could you maybe explain things like ratio and gain the compressors of amps like power amp in mobile devices

[@lekmannen9990]

Amazing video, I learned alot. How about a video about rise time and slew rate in different classes of amps. Thanks!

[@westernartifact580]

Good one.

[@jianhuang0124]

Great content. If there are more visual demo or flow chart showing, that'd even be better.

[@barlow2976]

Just what I was looking for, thanks.

[@simonzinc-trumpetharris852]

Excellent info.

[@CheapMessiah]

This is a great video, favorited for future reference as it saves a lot of writting time when explaining to people how headphones work. Personally i found out that people tend to understand better the concept of power to sound pressure conversion when you explain to them that the headphone impedance determines the amplifier maximum power, and then sensitivity is how efficiently a driver can convert that power to sound pressure. For some reason explaining it as "steps" makes that information easier to digest.

[@DJ_BROBOT]

I find that most people who arent WILLING audiophiles really don't care about this. Audiophiles care...most people will still buy those crappy Bleats, Bosé and Cowin Headphones off Amazon. I've seen this too many times where most people dont care about better sound and the technical of a headphone as much as we do. They just don't and I'm resigned to say that's okay.

[@enjoshi-godrez8775]

@@DJ_BROBOT we are not taking about those people.

[@Saitama07]

Thank you for this ❤

[@1as130]

would love specific review of the confusing aeon noire power requirements! also recommendations for desktop or mobile amps!

[@keithdunwoody1302]

This was very helpful, thank you. However, I would really like to see you display some various spec sheets from different amps and headphones and stare and compare the voltages and wattage and sensitivity specs so we can take this theory and apply it to a real world shopping situations.

[@louiev.3367]

A lot of my music library of the 80s doesn't get remasters so I have music that's so quite then the next track gets absurdly loud

[@danielhipwell3607]

great video, thank you.

[@mrykhoek]

The thumbnail for this video made me chuckle. I mean this in no disrespect, but the picture reminded me of Elmo St. Peters from The Brave Little Toaster lol. Love your videos!!

[@razisn]

Technically sensitivity should be expressed as a function of voltage not power, the way many (but far from all) speaker manufacturers express it nowadays. If you express 'sensitivity' as a function of power (wattage) what you are actually describing is 'nominal' efficiency. Nominal because it depends on impedance and the quoted impedance is 'nominal' because it often varies with frequency.

[@teqai]

Would be cool if in the calculator you could select the most common headphones, s.t. their values would be filled in automatically.

[@chrislj2890]

Excellent video, but I kept waiting for that vacuum tube to get whacked, lol.

[@fabimesizae]

Would it be possible to have a review of the Schiit Lyr headphone amplifier?

[@EricRosenfield]

This is really useful

[@asan1050]

Thank you

[@michaeljohansson3882]

It's like wine. You enjoy to explore different grapes, taste, and their texture. My reference i HD-600 (open) and DT-150 (DT-100 pads, closed) and Etymotic ER2XR (IEM)

[@Hialeah59]

Golden Sound - great video. I have Audeze LCD-5 headphones. My DAC is the Gustard X26Pro. I'm currently using an iFi iCan Pro Signature amp. Any suggestions on a new amp and or DAC to drive these cans? Thanks in advance.

[@ninja_rabbit_8684]

Just find this video,omg best explanation ever pal.I just start my hifi journey,hifiman sundara and I’m testing it with FiiO 7 and if zen dac,everyone say fiio is better cuz is more powerful but I also like zen dac and don’t feel Like is not loud enough or lack of power.Did you maybe review zen dac?

[@heyguyslolGAMING]

Great video, tyvm. Whats are Whats, no matter watt, lol nice.

There is one sense in which high impedance headphones are hard to drive. A lot of digital electronics, like the output stages of computers, phones, and digital audio players, do not have any form of impedance transformation (such as transformers) in their output stages, nor do they employ any kind of voltage boost in their power supplies. The amount of voltage they can supply on their outputs is strictly limited by the power supply voltage of the device. A device of that type may work well at driving a low impedance headphone, even if it requires a lot of current, but will fail miserably at driving a high impedance headphone because its maximum output voltage is 3.3 or 5 volts.

[@westernartifact580]

Yes, I think he missed this point, along with his outright blunder with his statement about class A/ab/d.

[@wardaug_]

would love some explanation for the formula/equation used in your Headphones Power Calculator. I've just found the equation to convert the sensitivity from dB/mW to dB/V: SV = SP + 20•Log(sqrt(1000/Z)), where Z is the headphones impedance. just wondering about the formula for required Voltage and Current. while Power I believe is the result of V*A Thanks in advance for the explanation!

[@tylerstravis]

What tube do you have in your Vali? I was hoping for a review of that thing :)

[@HiFiInsider]

A good amp with output transformer will have no problems with any impedance load. IMHO, the sensitivity rating is a more important factor to look at when researching headphones.

[@neilsnyder7915]

Plus more caveats. Since most people over the age of 1 and increasing with age, need to adjust balance. I need more wattage at 60 ohms since I attenuate the right channel down 15db. Always better to have enough power and gain reserve so error on the more power side.

[@martinfox2244]

Another suggestion, I have an original version Grado 225. I am considering a 325x but...what about a diy upgrade? Specifically how do diy drivers compare to factory Grados?

[@petercraig389]

Class A sounds better though.....more often then not... Good video !!

[@springersound1844]

Unmatched for my HD58X is my Pioneer sa8800 - haven't found better for black background and simple WEIGHT of sound. I play at very low volumes.

[@megametallifan]

This was great

[@astifcaulkinyeras]

Voltage is voltage and current is current but impedence is not resistance. Ohm's Law in an AC circuit is V=IZ. Impedence also varies depending on frequency. How this factors into a headphone circuit I have no clue.

[@wonjoomin]

Watt’s a Watt, no matter what! Nicely stated 👏

[@TimpBizkit]

High impedance means it doesn't draw enough power (but theoretically you could run lots of them in parallel on one amp so it's not the same as low sensitivity or efficiency). Low sensitivity means it needs lots (comparatively) of power to get loud, although sometimes sensitivity is measured in terms of voltage needed to get loud - which can also mean high impedance cans simply receiving less actual power, not just inefficiency.

[@lukedudgeon8699]

New to the hobby, stiill so much to learn......

[@tincedeng]

the position you put the tube amp and the way you waving you hands when talking really made me anxious.

[@martinfox2244]

Please explain OTL/non OTL tube amps vs hi/low headphone impedance.

[@westernartifact580]

High impedance headphones often sound divine on an OTL tube headphone amp: Dark Voice, LTA MZ, et. al.

[@framestomind7548]

how to choose one for your phone where it is a normal small headphone jack and how to know it will work'? I got the Light Phone 2 and got all my Apple Music and podcasts on it as well some recordings from Logic Pro... Now I use the beyerdynamic DT 1770 PRO and want to use them as well as with my phone to listen to music...

[@renzrulzz]

Does it means that a Focal Utopia 2022 for example will sound fine even with a less powerful amplifier? Or even a dongle DAC/AMP like the iFi Go bar or the AudioQuest Cobalt will be more than enough?

[@zemessargs]

Fantastic and informative, Goldensound. Despite being in the hobby for a bit now, and having nice gear, I learned quite a bit from this video. Thank you!

[@Decenium]

excellent

[@juhanihiltunen6737]

Hi, What you think about pairing Denon ah D 5200 and aune x1s GT pre amp dac`? do you have any recommends for those headphones? i have cables 4,4 mm so i prefer mostly same output amp. thank you. portable i have ifi hip da v3.

[@hmuhmunkunkuapua]

Still waiting for that deep dive into pcm vs dsd.

[@davide_notaro]

i didnt really get the part about planar (9:27) so let me recap if i've understood correctly: so if i listen at 85db the bass region in most song could be at 20db higher due to human hear stuff, so i plug 110 db in the calculator to see if i can drive it in the full range so in planar the bass is particulary hard to drive so the amp will output even more power towards those frequency and therefore i need an amp that drives cleanly even at higher power? so in practice what happens and how i check this? i have a fosi audio q5 that is rated for 400mW @32ohm and i'm intrested in a

[@onepieceatatime]

What's the tube in that little Schiit amp?

[@MrFLORESBR]

What about use a AV Receiver, such as Marantz SR-7013, to drive wired headphones? Is it any good?

[@Spliffstar5582]

Yes, you do!

[@jeroenvdw]

I recently ordered the Ananda BT because it's an open headphone with bluetooth, I expect it to come in a few days. I have 0 experience with open headphones, dacs, amps etc. so I was wondering if I should invest in let's say the Topping E50 + Topping L50 to up my game or wouldn't it do anything? I suppose it won't in BT mode, but when wired should I notice a huge difference? And I've read that this headphone has a build in DAC because that's needed for BT, so maybe just the AMP will be sufficient for it?

[@thewebart]

I can listen you day and night.

[@renflex_themullet]

One thing I dont quite understand is how to know from specs, how much power can put a certain amp in to a 300ohm headphone if the specs are given in mW for an headphone of 32ohm of impedance. Ca someone explain it 🙏 ? (the video is quite useful tho)

[@n0xt]

You can't really. At most you can assume that the amplifier outputs the same amount of voltage at these two impedances and work out the amount from P=U^2/R equation.

[@michaelshaffer4005]

In the context of headphones and IEMs, what does “scales with power” mean?

[@thekaying]

5:30 If anyone's got this down, care to explain? How does higher gain not equal higher output voltage in this description? And how does it not alter power as consequence?

[@markos.5539]

Can we have a database for THD vs Voltage?

[@jerryjones5547]

I don’t see a video on best headphones with glasses. Can you guys make on?

[@ZackMester]

My ZMF Atriums sounded fine coming directly from my iPhone so what is the point of a DAC or headphone amp?

[@matusjurcik6974]

I wouldnt say that higher impedance headphones draw less current. Transducers are moved by current and they need enough of it so higher impedance headphones need more voltage to flow enough current. In other words yes they can draw less current at given voltage, but they can be underpowered when the voltage is too low. I =V/R, where R means load impedance (headphone). The higher the R is the lower the value of the current flow (as u said), so u need higher value of voltage to achieve good amount of current flow to the transducers.

[@SlashThePriest]

So the max voltage of the amp is constant as you change the load (headphones)?

[@matusjurcik6974]

​@@SlashThePriestnot sure if I understood your question correctly, but voltage will be attenuated by the volume knob (so it depends on the loudness you are listening on, using given headphones). I hope I dont say bullshit, though 😅

[@SlashThePriest]

@@matusjurcik6974 Yes exactly, that was what I was trying to say with max voltage. As long as you don't change anything but the headphones the voltage should be the same. The output of the amp is limited by the voltage, so if I wanted to calculate the power of an amp with different impedance (headphones) than the spec sheet of the amp I would be able to do so with Ohm's Law by assuming that the voltage is constant.

[@matusjurcik6974]

@@SlashThePriest ok :) my OG comment was purely, about ohm law though (without consideration of volume adjustability ,,feature,, of an amp). Its alright to send control questions, though. I do it all the time 😁

[@kennetheavey8921]

How can I connect headphones to my amp without the speakers muting? I have a Yamaha A S301. I just need the speakers to play at the same time as the speakers.

[@zacharystokes]

You are defacto teaching people physics. This makes me happy.

[@mikehughescq]

An excellent video in terms of coherent explanation of key concepts but he doesn’t actually answer the question he poses in the title of the video. Do I need an amp?

[@fredmcdaniels2912]

Do a planar get sound from cellphone or dsd

[@twraia]

One thing I still don't understand: Is there a good reason to still buy and use an amp if I am using headphones which can be played at ample good enough volume across all my devices? Or maybe in more concrete terms, would something like Campfire Andromeda or the new Sony MDR-MV1 benefit from amp when both can be driven easily on a smartphone? Lots of people seem to suggest so, but what is the science behind that?

[@westernartifact580]

NOISE! Never mind the science. Isnt it enough for you to be told over and over again that phones and computers are horribly noisy? And we are not just telling you about audible noise (which may actually even be present). Get a separate dac/amp and you will hear for yourself.

[@sameh9310]

came for the reviews, stayed for the hi-fi science, left with no money

[@replacement6386]

I'd love to know what makes a headphone cost more or less? And does it always make it better?

[@blainelacross5311]

This is an excellent premise for a video, and I'll be pitching this to our content lead!

[@VJA74]

Though I respect you for being a great bridge between objective and subjective world, this video, though being quite informative, went zipped past. Would have been lot informative with bit lesser speed and with examples! 👍

[@oliverrevilo7654]

A question for the experts: Is the Ifi Zen Dac V2 powerful enough to power a Hifiman Edition XS? And does it absolutely need an external power pack, or is the power from the USB port sufficient? Thanks :-)

[@Mishael_Agyei-Boamah]

Yes the Zen DAC is more than enough... The Edition XS requires 63.1mW of power to get to the standard 110dB SPL as listed by Golden Sound. The Zen DAC can do roughly 350mW into 32 Ohm so yes it should be able to run the Edition XS no problem

[@MrThejograt]

So if power isn't an issue, then is it safe to somewhat assume that the sound changes from different DAC/Amp setups are more so on the pairing of those to the headphone? I remember trying to power my HD600 on my old Fiio Q1 Gen 1 and it was able to play it but the soundstage felt really narrow and there's a bit of a loss in clarity. Plugging it to a desktop headphone amp with my Topping D20 usually did the trick for me. I'd say that if it was more so the overall performance relative to the gear, then that could explain how different both DAC/Amps made the HD600 sound.

[@dmines25]

Components used can affect the coloring of sound. Since sound is translation of electricity to an audible signal, the parts that affect the signal's cleanness can alter that. It's the same reason not all headphones sound the same

[@KaneAmaroq]

It could be, and it could also be in your head. I'm not saying there's no audible differences between gear, but I found that in my own testing, once I set things up to no longer be able to tell what source gear I was listening to, an enormous amount of the differences went away entirely, and it became EXTREMELY hard to tell. I even did the same tests with a few of my friends who're huge audiophiles and spend thousands on source gear; I won't lie, the face they made when they couldn't tell if they were listening to a Modius or a Holo Spring 3 was a little funny. Hard to say for sure though without proper testing though, your brain is very very good at making stuff up based on your perception and expectations.

[@MrThejograt]

​@@dmines25 hmm makes sense, tuning, design and components do make headphones sound diff from each other so it makes sense too that it works for stacks too. Thanks

[@dmines25]

@tepellin_10 no problem. I actually like the discourse. It's refreshing to share info with others

[@MrThejograt]

​@@KaneAmaroq its a weird thing honestly Like at least in my memory, I tried pairing the HD600 with the Fiio X1/Q1 gen 1 combo, my Moto G 5G Plus connected to a Lake People G109(double amped), and with a G109/Topping D20 The Fiio portable stack powered the HD600 for sure but for some reason it sounded very narrow and because of that, the mids and highs sounded very close, although the hardware bass boost helped out the warmth a bit. Overall it wasn't very good My phone connected to an amp with no dac sounded quite good but the highs were a.bit lacking compared to the desktop dac/amp stack, although i would want to eventually do more testing on it eventually It could be all in my head so I'll also try to ask my other friends how they feel about it if they pass by