Sennheiser - HD 650

I have been using HD650 for two years now and this is my experience:

Sound:
This does not have a neutral sound signature - it inclines towards darker tone. The bass, even though slightly more pronounced, sounds amazing – with a solid body albeit a bit slow, and blends beautifully with the mids. The mids are clear, slightly dark. Both male and female voices sound beautiful. Highs are the weakest point of this headphone. They are laid back and not bright. Personally I prefer this, because this allows for prolonged listening sessions without getting fatigued whatsoever.

I primarily listen to western classical music. For specifically classical – string instruments sounds wonderful with intricate details, percussions are good as well – but bit slow. For Piano though – I am not very happy with a rather thin sound. However – this just maybe due to the dac and amp. Indian songs are reproduced with excellent details with a soothing quality. Jazz sounds exemplary in my experience.

Source dependency:
HD650 sound quality is highly dependent on the source. I have high quality 320kbps MP3 which sound surprisingly veiled. FLAC does better, but even a very minute noise in the file is noticeable. WAV sounds the best. I did not notice any significant quality improvement with DSDs.

Different amps and dacs sound very different with this headphone. Better to mix and match depending on music preference. Note that you need a decent set of dac+amp for this headphone – else it will not do justice to the quality of sound HD650 can produce.

I use Fiio X5 II and Fiio E12A (this has a brighter tone which complements nicely with darker tone of HD650) as my all-time-use setup with HD650.

Summary:
Paired with a good amp and dac, HD650 is an amazing headphone for relaxed and lazy listening. This headphone is pure joy to listen to even for a prolonged time. If you just want to close your eyes and enjoy the music without being analytical – HD650 is possibly the best headphon...

This headphone is more refined version of all time classic hd600. Initially it sounded muffled and bass heavy but after about 100 hours with isotek burn in track it sounds extremly clean and detailed. Bass and mid bass are lot fuller and sound has lot more body. Treble is one of the most clean and refined you would ever hear. There are no peaks to frequency response and sound is extremely smooth. I use it with chord mojo and it does full justice to mojo's insane resolution. People coming from beyerdynamic sound may feel the combo with mojo a bit on warmer side but I bet mojo plus hd650 combo is impossible to beat even with much more expensive headphones simply because this headphone has one of the least distortion figures. Impedance of 300 ohm goes very well with mojo and mojo gives plenty of volume and I never needed to go beyond green to light green volume of mojo and still plenty of volume range of mojo left. People looking for high end sound need not to see beyond thid headphone. Only one thing is that to enjoy the music fully with this headphone you need to listen in a calm environment as it is a open back design and easily affected by ambient sound. Overall great buy for audiophile and all music lovers alike.

These sound very flat compared to any other headphones in this price. Perfect for mixing.

Sennheiser - HD 650

Absolutely best headphone you can buy within the price range.

Very balanced and flat sound. One of the best headphones an audiophile can have.

there are always fotm headphones, having heard every flagship from almost every company, i keep coming back to the hd 650, if fed via a good dac and a tube amp, it wud put most modern kilobuck headphones to shame. extremely resolving and mids to die for

Sennheiser - HD 650

Coming from a pair of Sennheiser HD 598s, the 650 is a great upgrade, but needs external amplification due to its high impedance. Running my setup with an external Topping DAC and Fiio amp, the sound was beyond amazing. It was so good that I almost wept when listening to a high res version of Iron Maiden's Senjutsu album. However, my only issue with this product is the clamping force exerted by the headband, which might be attributed to it being new and may decrease with time. It is quite high and makes listening to music for long periods of time slightly uncomfortable. It's also a very scalable pair of headphones, so looking forward to pairing it with better amps/DACs in the future ;)