Sennheiser HD6XX Headphones

The band is Hifiman and the model in Sundara.
I don't think anything beats Sennheiser for quality of build in their price point, but the Sundara sound is more pleasing.

Both are considered 'reference' to compare other headphones to.
The 6xx are dynamic driver and closed back, the Sundara are planar and open back.

If you are going to travel with the headphones I'd go Sennheiser, if they are going to sit on a desk, I'd go Sundara.
The sound difference between the two is significant, but the Sundara and the 6xx are the two kings of their price point IMHO.
Actually the HD650 are not closed back...
 
I love my HD6XX’s! They work great with the Axe, no issue driving them. For casual listening, my iPad drives them well, but the iPhone can be a touch quiet at times. Actually I use them for mixes too when I‘m away from my studio monitors setup, and they work well for that when needed! Personally I would recommend them, but I too am a fan of the Sennheiser “sound”
 
Been using the HD650 for many years. They are great headphones and are easily driven by the axe fx headphone out and my Apollo twin HP out. You don’t need a dedicated amp, though audiophile forums will tell you to buy tube amps. They do have a bass hump and some notches in the 2K region. I have an IR that flattens them, which I use when building presets. They translate remarkably well after that adjustment.

Meaning to try a planar set, either Hifiman Sundara or Arya (this is $$$$) or maybe Audeze.
 
Last edited:
Hearing is a truly personal thing, we all hear a little differently, so YMMV...

but to me the Sennheiser 6XX sound is a little veiled in the highs. Like there is a thin cotton curtain over the speakers. They are good for long listens, they aren't fatiguing, but my ideal response in both the very low end and the higher highs is more aligned to the Sundara. I think this is because it's a planar but again I'm no audiophile. People seem to love Sennheiser for the mid range and I have no argument with that, I hear that too. As I said, it's no coincidence Senn's lasted for so many people. I think they stomp the competition in quality for price.

I actually prefer the new IE600 from Sennheiser, their in-ears, to the 6xx, so it's not a brand thing, we just all like different tunings - and even from the same company there is variance within a line. The 6XX is not the 600 nor is it the 660S.
 
Last edited:
Ax3's headphone jack will power them just fine.

All 4 of Sennheiser’s 6 series are open back, not semi-open back, and this is obvious when comparing their sound stages to that of any semi-open back or closed back headphone. It’s also obvious from the design and it’s stated on their website.

The high end on the 650 and 6xx is more rolled off than on the 600 making them less accurate than the 600. In that price range the 600 was the most accurate headphone I’ve tried, but the Ollo S4X far surpasses it in terms of accuracy / flat response, particularly in the tightness and clarity of the low end, and they’re pretty close to the same price on the used market judging by reverb and what I recently sold mine for (now using Ollo S5X). It really is something else hearing the separation between the kick, synth bass, and bass guitar in a modern track and not just a wall of hyped low end mud.

No experience with the Sundara but the frequency response graph looks quite good if the goal is accuracy, though there are many other variables to consider when choosing headphones so I can’t confidently recommend them based on the graph alone.
 
Last edited:
False marketing? Or some hi tech definition they are not?
Huh?

Look at Sennheiser’s site if you want the full information.

The HD-650 are open back, nothing close to any of the closed-back headphones I have ever had, and they sound great. They’re wonderful for critical listening and mixing, but not for recording because open-back headphones leak sound into vocal or instrument mics.
 
Huh?

Look at Sennheiser’s site if you want the full information.

The HD-650 are open back, nothing close to any of the closed-back headphones I have ever had, and they sound great. They’re wonderful for critical listening and mixing, but not for recording because open-back headphones leak sound into vocal or instrument mics.
Exactly, it seems some just want to differ every waking moment. Sure seem open back to me as well, my post was a response to a mention they were not open back* sennheiser seems to think they are, Not sure why they would sell them as open back if they were not. Maybe there just a shit company trying to rip people off( heavy sarcastic remark)! I'd love to have a set
 
My Sennheiser HD650 just arrived. Well packaging is a bit lackluster but looking forward to trying these out after work
 
Initial impressions with the HD650's connected to my Apollo X6. Very comfortable fit. I can see why many like these for extended listening sessions. My Apollo X6 HP input don't seem to be driving these with ease but not terrible either. Anything under 12 noon on the HP level is whisper quiet. I have to dial in at least 3 o'clock to get decent volumes. Technically I don't think I 'need' a dedicated HP amp but if its taking this amount of level to drive these headphones will I gain a better 'fidelity' /listening experience going through a HP amp? I don't necessarily need louder than it can put out just wonder if I'd be missing anything quality wise...

edit: Comparing to my atomic CLR"s and the 650's they translate very well.

Looked up spec in my manual for the Apollo X6 headphone output:
Maximum Output Power (into 300 ohm load) - 150 mW RMS
the Senn 650's are 300 ohm. On the Universal Audio forum I came across this comment and I will admit I don't understand the implication of UA using a 'IC chip' to achieve the power output.
Here's the quote from the forum: "Even though the headphone amps in the Apollo's now have the current supply capability to drive high impedance phones, they are still using an IC chip to achieve this"
 
Last edited:
Audiophiles will tell you that you’ll get more sub bass slam with more headroom in the power amp but I question if this measures out to be true. I think it’s “hearing with the eyes”
 
I would tell you to get the Hifiman Sundara instead of the 6xx for enjoyment. I own both and the Sundara gives a much more "soundstage" as the audiophiles like to say. They are open back and feel more like a playing in room than playing thru headphones. The low end has more "slam" and the highs are a little more open.
Hifiman Sundara’s are great headphones for the money for sure
 
Here's the quote from the forum: "Even though the headphone amps in the Apollo's now have the current supply capability to drive high impedance phones, they are still using an IC chip to achieve this"
I'd ignore this. Audiophile forums want to run these headphones with tubes and not solid state. Tubes objectively measure worse than solid state and any benefits people think they hear are because of distortion, artifacts and change in the frequency response due to those amps.
I have a headphone amp too. They are no better or worse than the newer Apollo interfaces for driving HD650. I'd rather adjust the eq to flatten the response a bit (bump up the 2K, reduce the bass).
 
Back
Top Bottom