Home  Donate  New  Search  Gallery  Reviews  How-To  Books  Links  Workshops  About  Contact

Sennheiser HD 650
Professional Open-Back Headphones

Intro   Specifications   Sound   Bass  

Sensitivity   Mechanics   Ergonomics  

Usage   Compared   Recommendations   More

Please help KenRockwell..com

Sennheiser HD 650

Sennheiser HD 650 (300 Ω, ¼" plug with 3.5mm cable adapter, 9.1 oz./259g, about $500.) enlarge. I got mine at Adorama; Amazon and B&H also have them. This ad-free website's biggest source of support is when you use that or any of these links to approved sources when you get anything, regardless of the country in which you live. Thanks for your support! Ken.


DEAL: HD 650 with free $300 Apogee Groove DAC! I have a Groove on the way to review; it's a $300 professonal Made-in-USA USB DAC & headphone amplifier.


September 2015

All Reviews  >  Audio Reviews  >  Headphone Reviews >  Sennheiser Reviews


Introduction         top

Intro   Specifications   Sound   Bass  

Sensitivity   Mechanics   Ergonomics  

Usage   Compared   Recommendations   More

Adorama pays top dollar for your used gear.

B&H Photo - Video - Pro Audio

The HD 650 are much smoother and warmer than other open-back headphones, and have much deeper bass. They are very well made, comfortable and durable. They tend towards too warm, meaning that the highs are slightly suppressed compared to other headphones. These are ideal for those who prefer big, warm sound (think Rachmaninoff), but less ideal for those who prefer light and bright (think Vivaldi).

Regardless of your preference for overall balance, as one of the world's top headphones they are completely devoid of any coloration; there are no peaks or valleys in their response and they are exceptionally smooth.

The Sennheiser HD 650 have been Sennheiser's top-of-the-line professional headphones since they were introduced in 2003.

Sennheiser has newer and more expensive HD 800 and HD 700 headphones for consumers more impressed by fancy boxes, fancy cables and goofy-looking semimetallic housings, while these professional HD 650 sell for much less today because they have been in the catalog for so long and they are made of more practical materials. Their lack of flashy chrome means we can get professional sound for much less than the consumer models, and they are tougher, too!

Sennheiser has been one of the world's top headphone makers for numerous decades, and invented the open-back headphone in 1968. Today, Sennheiser owns Neumann, and the two of them together make most of the microphones used for professional recording. Most of the music that you'll be enjoying through these headphones probably was recorded through Sennheiser or Neumann microphones.

These HD 650 are so loved because they give us the exact sound that's in our recording, nothing more and nothing less. What's so remarkable is how unremarkable they sound. The HD 650 don't emphasize or remove anything; what you hear is what you've got.

Since they don't emphasize any of the treble, they lack the usual Hi-Fi "sparkle" added by most other consumer headphones. Therefore they aren't as exciting to listen to for music enjoyment; they'll sound duller than more common headphones or the more Hi-Fi oriented HD 800.

These are the real thing for pro use, made in Ireland with a studio-standard ¼" plug.

These 300Ω headphones are optimized for use with pro gear, good home and classic Hi-Fi gear. They work best plugged directly into a good CD or SACD player, Hi-Fi amplifier or receiver.

They also work great — just not very loud — with your iPhone, iPad and iPod. They sound great for portable use, but won't go as loud as 32 Ω headphones. They will sound outstanding, just that you'll have to turn your volume control most of the way up on portable players.

A short adapter cable is included for use with consumer 3.5mm jacks, but the thick plug grip won't poke through some thicker iPhone cases. Likewise, there is no remote control on the cable.


Specifications         top

Intro   Specifications   Sound   Bass  

Sensitivity   Mechanics   Ergonomics  

Usage   Compared   Recommendations   More



Sennheiser HD 650

Sennheiser HD 650 driver. bigger.

Dynamic drivers with aluminium voice coils.

Open-Aire (open-back).

Drivers selected for ±1 dB matching.


Impedance        top

Rated 300 Ω.

I measure about 360 Ω:

Sennheiser HD 650 box

Sennheiser HD 650 on-head measured impedance, left side.


Sennheiser HD 650 box

Sennheiser HD 650 on-head measured impedance, right side.

I've expanded the vertical scale to exaggerate the variation in impedance versus frequency. The impedance varies only ±20% and the phase angle stays within ±10º over the audio band, so these are a very easy load for any source to drive.


Sensitivity        top

103 dB at 1V RMS at 1 kHz.


Power Handling & MOL        top

500 mW per EN 60-268-7.

500 mw at 300 Ω is 12.25v (21.76 dBV) which should produce 124.76 dB SPL


Frequency Response        top

16 ~ 30,000 Hz at - 3dB

10 ~ 39,500 Hz at - 10dB

Diffuse-field equalized.


THD        top

< 0.05% at 100 dB SPL at 1 kHz.


Cord & Plug        top

10' (3m) straight cord.

OFC wire and aramid fibre reinforcement. (replacement part number 092885, about $25.)

¼" plug.

3.5mm adapter cable included.

Sennheiser HD 650

Sennheiser HD 650 removable cable and included 3.5mm adapter. bigger.

There's an optional balanced cable CH 650 S (about $250) for use with Sennheiser's amplifiers. I wouldn't bother with it.


Ear Cushions         top

Foam covered with fuzzy felt.

Replacement part number 050635, about $70 the pair.


Head Pressure        top

2.5 Newtons.


Quality        top

Made in Ireland.


Weight        top

9.130 oz. (258.9g), actual measured, no cord.

Sennheiser rates it as 260g.


Price, USA        top

Usually sells at $500 in 2014 and 2015, but often discounted.

It has sold for as little as $315 in December 2014 at Adorama when I got mine.


Sennheiser HD 650 box

Sennheiser HD 650 outer box cover.


Sennheiser HD 650

Sennheiser HD 650 inner box. bigger.


Sound         top

Intro   Specifications   Sound   Bass  

Sensitivity   Mechanics   Ergonomics  

Usage   Compared   Recommendations   More


I burnt these in at 94 dB SPL with pink noise for 75 hours before I used them.

The HD 650 are very accurate headphones. The low and high ends are not boosted, but the low end is significantly more extended than I'm used to hearing with open headphones.

The HD 650 are smooth and clean, and have great deep bass.

They are a little duller than most headphones. They lack the "sizzle" of Hi-Fi headphones, most of which have boosted high ends. Setting a treble control to about +2 dB at 10 kHz makes these sound closer to other common headphones. These are ideal for people like me who find most headphones, like the HD 800, too bright.

The HD 650 are warmer and darker, or make it sound as if you're sitting a bit farther back in the audience.

They are very neutral, but not sweet like Hi-Fi headphones. There are no audible resonances or coloration.

Nothing sticks out about their sound; they just have loads of big, fat, smooth sound with a fantastic low end.

These have extremely low distortion on voices and woodwinds, with a very fluid tube-like midrange.

As open headphones, there's about as much sound coming out the back. My 7-year old Katie thinks they're broken because the music is coming out the back!

Shine a light through them and you can see through them dimly.

They sound almost the same if you cover the backs with your hands.

The sound doesn't change much as moved around my head.


Bass         top

Intro   Specifications   Sound   Bass  

Sensitivity   Mechanics   Ergonomics  

Usage   Compared   Recommendations   More


I can't ever recall hearing bass this good out of any other open dynamic headphone. It's strong, full-bodied and solid — but not boosted.

It's deep, solid and tight —  but only if its recorded that way. These are great for hearing exactly what you have.

It has very well articulated bass. Whatever's played and recorded is what you'll hear. Other might call this textured or detailed, but what we're all saying is that the transient response is very well damped so it doesn't much up the bass. Bravo!

Unlike most consumer headphones that jack-up the bass so every piece sounds about the same, the neutral bass of the HD650 makes every piece sounds different. It's excellent for evaluating recordings, since what you hear is what you've got.

It's very good for pipe organ, easily reproducing all of the 16 foot ranks. 32 foot ranks sound very good, but you won't quite hear all of the Cs and Ds — but very few things can reproduce sub-20 cycle notes like these.


Sensitivity         top

Intro   Specifications   Sound   Bass  

Sensitivity   Mechanics   Ergonomics  

Usage   Compared   Recommendations   More


Home and Studio

All decent home and studio gear has loads of output for driving these.

These live for real signal levels that come from equipment with ¼" jacks.

Their 300 Ω impedance lowers the distortion from all devices, and their sensitivity is optimum so we won't hear any amplifier noise.

Most equipment with ¼" jacks puts out at least 4 V RMS into 300 Ω loads, so it's easy to deafen yourself with these from any real equipment.



My 27" iMac with 5k Retina Display puts out 2 V RMS from an 0.5 Ω source impedance at its rear headphone jack, which is plenty for driving these headphones for music enjoyment.

For pro music editing you might want to drive them from an outboard amplifier, but for music, most people probably don't realize that the newest iMacs have great headphone amplifiers.


iPhone, iPad & iPod

You may or may not be happy with these as plugged into 3.5mm jacks.

I have no problem enjoying everything on my iOS devices, which only put out 1 V RMS maximum.

Pop music is fine, but I usually have the volume all the way up for classical music.

I have to play movies at 3/4 to full level, where with 32 Ω headphones I play the same things at about 1/2 to 3/4.

If you don't demand the ability to blow your brains out, these work great with iOS devices.

At 300 Ω these will have less distortion than 32 Ω headphones when driven by most real-world portables, so if the levels are enough for you, you're good to go.


Mechanics         top

Intro   Specifications   Sound   Bass  

Sensitivity   Mechanics   Ergonomics  

Usage   Compared   Recommendations   More


Here's another reason I like these so much: they are tough, solid and reasonably light weight.

They are not delicate; they are easy to move around and put down without having to worry about scratching or breaking something. They are made of very tough plastic. These are professional headphones made in Ireland, not disposable consumer garbage from China.

The HD 650 are all plastic, except for the adjuatble spring band.

I'd even call them kid tough; if your kids don't go wiping peanut butter on them, I have no problems letting my kids enjoy Mozart or Schubert when they ask to put them on.

Katie enjoys Schubert over the Sennheiser HD 650 headphones

Katie enjoys Schubert over the Sennheiser HD 650 headphones.


Ergonomics         top

Intro   Specifications   Sound   Bass  

Sensitivity   Mechanics   Ergonomics  

Usage   Compared   Recommendations   More


These feel great. They have firm clicks for sizing, so they stay adjusted. Adjust them once, and you're done.

The gimbals have some stiction, so they tend to stay as you've adjusted them. The gimbals move to cover any shape head I can imagine.

They have reasonably firm head pressure. You can feel the fuzzy thin earpads' elliptical shapes pressing on you. Likewise, combined with their light weight, they stick on my head as I move around.

The left earpiece is clearly marked with three little tits easily felt as you put these on. As we all know, those three little tits are "L" in Braille.


Compared         top

Intro   Specifications   Sound   Bass  

Sensitivity   Mechanics   Ergonomics  

Usage   Compared   Recommendations   More


Versus the beyerdynamic DT880 (600 Ω)

The beyerdynamic DT880 are similar open headphones, and come in 32 Ω, 250 Ω and 600 Ω versions. I own the 600 Ω version. All have the same sound and impedance curves, and vary simply in their voltage sensitivity while the power sensitivity stays the same.

The 600 Ω DT880 have a little less voltage sensitivity than the 300 Ω HD 650. If you are using an iPhone, get the 32 Ω DT880. The 250 Ω DT880 probably is abotu the same as the HD 650, while my 600 Ω DT880 are a little less loud played with an iPhone.

The DT880 are brighter, lighter and clearer than the HD 650. The DT880 also have great deep bass. Both the DT880 and HD 650 are devoid of any coloration; the difference is that the HD 650 sound as if the treble has been turned down a click (2 dB).

The DT880 have mostly metal housings and harps.

The DT880 are made in Germany, while the HD 650 are made in Ireland.

I usually prefer the DT880; I find the HD 650 too dark, although I will tend to play the DT880 louder to make the bass more audible. The HD 650 has plenty of bass at lower levels. Use the DT880 at loud levels, while the HD 650 sound better played softly.


Versus the beyerdynamic T51i

The beyerdynamic T51i are closed, portable 32 Ω, 3.5mm plug headphones.

The T51i are slightly brighter, with a more boosted Hi-Fi response. These HD 650 sound slightly cooler; the T51i slightly warmer.

These HD 650 don't fold; the T51i do.

These HD 650 are all plastic, while the T51i are all sheet metal.

The T51i has more very top end, it opens-up the sound as most Hi-Fi headphones do.

The T51i are sweeter and have more deep bass; the T51i have more "shine," which is as we expect since the T51i are Hi-Fi headphones trying to make our music sound better, while these professional HD 650 are trying to show us our recordings exactly as they are.

THe T51i are made in Germany, while the HD 650 are made in Ireland.


Versus the Audeze EL-8

The Audeze EL-8 ($700) sound darker, while the HD 650 are more present.

The EL-8 are cuppier and less detailed than the HD 650. The HD 650 have far more detail and are still very smooth.

They have about the same deep bass. There is maybe more bass detail in the HD 650 but more thud in the EL-8.

The EL-8 have more sensitivity when driven by the same voltage.

THe EL-8 are made in USA, while the HD 650 are made in Ireland.

I prefer the sound of these HD 650.


Usage         top

Intro   Specifications   Sound   Bass  

Sensitivity   Mechanics   Ergonomics  

Usage   Compared   Recommendations   More


With their 300 Ω impedance, they are easy to drive and ensure you'll get low distortion. That's the advantage of 300 Ω headphones, but it also means they won't play as loud with portable devices as common 32 Ω portable headphones.

These HD 650 sound great plugged into anything. While they sound great with my Benchmark DAC1 HDR, they also work great with my iOS devices — just not as loud.

The included 3.5mm adapter cable has a big grip that won't be able to poke into a protective iPhone case. If you use a thick case you may need an adapter with a special thin grip.

Stiction helps keep the gimbals set. Remember to adjust them deliberately; they won't just flop into place.

If you prefer brighter sound, move them forward on your head. Move them back if you prefer darker sound.

Be sure to set Sound Check to "On" in your Music app or in iTunes if you can't play them loud enough for soft pieces. Sound Check turns up the level of softer songs (and it turns down the level of louder ones). I always leave Sound Check ON. It doesn't compress the levels within any song, it compensates for variations between songs. It helps let us play soft songs or movements loud enough to hear them on iOS.


Recommendations         top

Intro   Specifications   Sound   Bass  

Sensitivity   Mechanics   Ergonomics  

Usage   Compared   Recommendations   More


The HD 650 have been tops for home and professional use for over a decade. I love how neutral they sound, along with great bass, in a tough and durable package at a reasonable price, and they're made in a free country.

They are optimized for use with real Hi-Fi or professional equipment. Ideally use a man's amplifier or any classic Hi-Fi gear.

The HD650 may not be sensitive enough for headbangers, metalheads or drummers when plugged into iOS devices, but for reasonable people, they sound great.

I've enjoyed them for hours plugged into nothing more than an iPod Nano, but if you use these primarily with portables, I'd suggest the beyerdynamic T51i instead.

For portable use, I prefer my Beyerdynamic T51i because their case and design packs and travels better; they also plug directly into my iPhone with its heavy protective case. Soundwise, I prefer the more Hi-Fi sound from my T51i to the more neutral sound of the HD 650.

You probably don't need a dedicated amplifier, but if you want a good one at a bargain price, consider the classic Crown D-75 which can drive the HD650 to deafening levels. It has a regular ¼" headphone jack and volume controls right on it. It's far better to spend $500 on headphones and $100 on an amplifier than to spend $200 on headphones and $300 on an amplifier. Your headphones are much more important than your amplifier.


More Information         top

Intro   Specifications   Sound   Bass  

Sensitivity   Mechanics   Ergonomics  

Usage   Compared   Recommendations   More


Sennheiser's HD 650 User's Manual.


© Ken Rockwell. All rights reserved. Tous droits réservés. Alle Rechte vorbehalten.


Help me help you         top

I support my growing family through this website, as crazy as it might seem.

The biggest help is when you use any of these links to approved sources when you get anything, regardless of the country in which you live. It costs you nothing, and is this site's, and thus my family's, biggest source of support. These places have the best prices and service, which is why I've used them since before this website existed. I recommend them all personally.

If you find this page as helpful as a book you might have had to buy or a workshop you may have had to take, feel free to help me continue helping everyone.

If you've gotten your gear through one of my links or helped otherwise, you're family. It's great people like you who allow me to keep adding to this site full-time. Thanks!

If you haven't helped yet, please do, and consider helping me with a gift of $5.00.

As this page is copyrighted and formally registered, it is unlawful to make copies, especially in the form of printouts for personal use. If you wish to make a printout for personal use, you are granted one-time permission only if you PayPal me $5.00 per printout or part thereof. Thank you!


Thanks for reading!



Mr. & Mrs. Ken Rockwell, Ryan and Katie.


Home  Donate  New  Search  Gallery  Reviews  How-To  Books  Links  Workshops  About  Contact





21 September 2015, December 2014