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Sennheiser HD660 S vs HD650 - Which side are you on?

A Surfer

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Output R will be very close to 0.

Without attenuation you might hear background hiss.
You could always make a passive attenuator.
Low impedance much much lower than headphone out on power amps), lower noise floor (because of attenuation), less chance of accidentally blowing up (lower impedance) headphones and possibly even your hearing.

> 300Ω headphones usually can be connected to medium power speaker amps directly.
Thank you, I appreciate the information. I have been using a speaker tap cable for years with many headphones (same amp) that cover the gambit from 16ohm (Onkyo H500M) up to 300ohm HD800S. I was never sure what the R would be at the terminals, but I had always assumed it would be extremely low. Cheers.
 

3125b

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but I had always assumed it would be extremely low.
Correct, near zero. Has to be since speaker amps deliver a lot of power to low impedance loads.
 

A Surfer

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I have been so extremely satisfied with the use of the speaker tap cable and integrated amp to drive my headphones. If I was to list the models I have owned and driven directly from the speaker terminals it would take a little time to type. What a fantastic solution and I am very fortunate in that NAD did a fantastic job with the M3. I don't notice background hiss at all (or the levels are so low that I don't really notice). I had Trevor at Norne Audio build me the speaker tap cable and he did a great job. Nice materials, certainly well made and for what it is worth it is a very nice looking cable. I will never need a dedicated headphone amp again as far as I can tell.
 

*Cihan*

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My message isn't related with the topic but I wanted to write here since I used to ask a comparison between k612 pro here. Now I have both AKG K612 pro and Sennheiser HD6XX. I can say that they're both good but somehow I feel AKG k612 pro has more clear, refined sound. And bass seems better in k612 pro to me by quality. I strangely feel HD6XX has less treble but sometimes I feel a spike in treble. I don't have this feeling with K612 pro. And another thing seems strange with HD6XX is that I feel like I'm hearing some standing wave on some bass notes. I don't know if this is because there's some reverberation or echo inside the ear cups.
I hear the standing waves very well in this record. But I don't know if it's room reverberation. I hear these standing waves more with HD6XX.

They're both good but I can say k612 pro is really good for the price.

Note: I listened both without equalization.
 
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Streamc

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owned both. 660 Keep 660. In 15 percent 650 was better but lack of hi freq. And I stop listen many music on 650 and returen after 660.
I boight HIFIMAN SE and close allmost of 15 percent.
Maybe LCD-X would be better but it is another league. :)
 

AyeYoYoYO

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For me it's 600 > 650 > 660S.
Technically they're all not that different, not enough to really matter (while the 660S has different drivers, that doesn't matter too much).
The 600 is the cheapest and the brightest sounding, somewhere between Harman and DF, wich I like.
The 660S is clearly related to the other two, but with less presence and even worse bass extension, I just don't get why it is the most expensive one. The 58X is clearly the better deal if you want to go in that direction, even with import fees.
The 660S comes with a balanced cable wich is not needed, all of them are fairly easy to drive.
I agree with the bulk of what’s stated here.

The 600’s are the best FR for reference, and the best & most balanced sounding overall to the widest audience. They’re the most true to what was recorded, from amongst the HD6__ line.

The 650 is the darkest, most pleasant/smooth for people overly sensitive to sibilance and treble, and will slightly improve the listenability of older hissy-sibilant 20th century recordings.

The 660S is the first step to modernize such a classic, comfortable/ergonomic, timeless housing/headband design, with the newer lightning fast drivers from the HD700, but IMHO, is lacking the presence, treble and air required to ever be considered for professional use. It’s a great set for those who love the darker presentation of the 650, but wanted more speed and tightness.

I absolutely cannot wait for Sennheiser to finish running this same HD700 driver more to the HD600’s tuning, to create a faster, tighter more modern HD600, and will likely name it HD610S, and house it in a somewhat similar colorway as the classic grey marble 600, to clearly & universally convey the tuning/profile/legacy-continuation.
 

AyeYoYoYO

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My message isn't related with the topic but I wanted to write here since I used to ask a comparison between k612 pro here. Now I have both AKG K612 pro and Sennheiser HD6XX. I can say that they're both good but somehow I feel AKG k612 pro has more clear, refined sound. And bass seems better in k612 pro to me by quality. I strangely feel HD6XX has less treble but sometimes I feel a spike in treble. I don't have this feeling with K612 pro. And another thing seems strange with HD6XX is that I feel like I'm hearing some standing wave on some bass notes. I don't know if this is because there's some reverberation or echo inside the ear cups.
I hear the standing waves very well in this record. But I don't know if it's room reverberation. I hear these standing waves more with HD6XX.

They're both good but I can say k612 pro is really good for the price.

Note: I listened both without equalization.
While AKG’s future in the professional market remains dim and uncertain … what 00’s AKG was able to push forward with its K6__ & K7__ Lines is really important & significant to the overall advancement in the industry.

And as great as each respective model in the K6__ & K7__ lines are, the K612 is the most neutral, and such an incredible value for what it’s able to give in terms of FR, soundstage, placement, detail, imaging, and delectation. Headphones at significantly higher price points, can’t offer what the best of the K6__ & K7__ line do effortlessly.
 

tamask01

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My opinion:

Bass extension: HD58X > HD660S > HD650 > HD600 (with perfect seal of course)
Bass quality: HD660S > HD58X > HD600 > HD650
Mids quality: HD660S > HD58X > HD600 > HD650
Warmth: HD650 > HD58X > HD660S > HD600
Clarity: HD600 > HD660S > HD58X > HD650
Treble quality: HD650 > HD600 > HD660S > HD58X
Treble level: HD600 > HD660S > HD58X > HD650
Smoothness: HD650 > HD600 > HD660S > HD58X
Liveliness: HD660S > HD58X > HD650 > HD600
Neutral sound: HD600 > HD660S > HD58X > HD650

Did you find either the HD650 or the HD660S's unequalized treble harsh and sharp, so much so that it results in fatigue and headache?
I mentioned in a thread earlier that I had a pair of Sundaras that were amazing but had to return them because I couldn't play games on them. The gunshots were terribly harsh even on low volumes and gave me a headache 10 minutes in.
 

NDRQ

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Did you find either the HD650 or the HD660S's unequalized treble harsh and sharp, so much so that it results in fatigue and headache?
I mentioned in a thread earlier that I had a pair of Sundaras that were amazing but had to return them because I couldn't play games on them. The gunshots were terribly harsh even on low volumes and gave me a headache 10 minutes in.

Just as i heard, the Sundara can be really bright and sibilant. The HD650's treble is one of the smoothest treble in the headphone world, the 660s a bit brighter, but still very good. If you are sensitive to treble, the Sennheisers HD6x0 is the idealé choice. Butter smooth, but still really detailed.
 

solderdude

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Did you find either the HD650 or the HD660S's unequalized treble harsh and sharp, so much so that it results in fatigue and headache?

Neither have harsh or sharp treble.
A headache can be caused by a high clamping force. Lowering the clamping force may be what is needed.
The HD660S improves with some slight filtering around 6kHz.

Sundara's have a treble peak at 9-10kHz which is there but not registered by specific HATS so on those fixtures it appears it does not need EQ there but it does. Measurement error as it were.
 

tamask01

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Neither have harsh or sharp treble.
A headache can be caused by a high clamping force. Lowering the clamping force may be what is needed.
The HD660S improves with some slight filtering around 6kHz.

Sundara's have a treble peak at 9-10kHz which is there but not registered by specific HATS so on those fixtures it appears it does not need EQ there but it does. Measurement error as it were.
Thanks, then judging by your earlier experience with these headphones I think I'll try a HD660S.
The clamping force of the Sundaras were perfect for me, very comfortable pair and listening to bass boosted music was not fatiguing at all. Gunshots in games were terrible though :/
 

Paweł L

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One can always use some of the Solderdude's tricks to mellow the treble down ;) I didn't try the Sundara, but I guess there might be a way to filter the offending highs a bit.
Sennheiser 6** series are usually described as veiled or boring by Beyerdynamic or AKG, Grado lovers.
 

tamask01

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One can always use some of the Solderdude's tricks to mellow the treble down ;) I didn't try the Sundara, but I guess there might be a way to filter the offending highs a bit.
Sennheiser 6** series are usually described as veiled or boring by Beyerdynamic or AKG, Grado lovers.
I was about to run out of the return period, it made more sense to just return them and get a refund :(
Note I'm not an actual audiophile like you guys here. I play games, listen to youtube or watch movies only. I just want a decent sound for these, my current Plantronics blackwire just ain't cuttin it :D
 

Paweł L

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I was about to run out of the return period, it made more sense to just return them and get a refund :(
Note I'm not an actual audiophile like you guys here. I play games, listen to youtube or watch movies only. I just want a decent sound for these, my current Plantronics blackwire just ain't cuttin it :D
Solderdude site diyaudioheaven is full of headphone reviews and cheap diy mods. Some toilet paper over the drivers sometimes does the trick. Or RLC filter in line with the cable, if you are able to melt some solder. Worth checking it out.
 

tamask01

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Solderdude site diyaudioheaven is full of headphone reviews and cheap diy mods. Some toilet paper over the drivers sometimes does the trick. Or RLC filter in line with the cable, if you are able to melt some solder. Worth checking it out.
That def sounds interesting and I'll check it out but as long as I have my warranty for these, I wouldn't void it by taking these apart.
 

Paweł L

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The RLC trap can actually made additional female and male plug with some cable. For other mods only removal of pads is needed, which shouldn't void warranty, since pads are parts which are user replaceable. Headphones like DT1990 actually come with two sets of pads to change sound characteristics.
 

tamask01

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The RLC trap can actually made additional female and male plug with some cable. For other mods only removal of pads is needed, which shouldn't void warranty, since pads are parts which are user replaceable. Headphones like DT1990 actually come with two sets of pads to change sound characteristics.
ty, I didn't know that. then again, these will be my first pair of proper headphones (if you don't count having the Sundaras for a short time) :D
 

tamask01

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I got my HD660S, some thoughts on them, running with a Fiio K5 Pro and listening to music on YouTube like the peasant I am -

Out of the box they definitely sound a bit more veiled and damp than the Sundaras, I wouldn't say they are worse though. HD660S is definitely an accurate pair.

I don't have that annoying high pitch crackling and peaks I had with the Sundaras. I could listen to these for hours on end.
For the Sundaras, "S" sounds were terribly painful and loud, so are gunshots in game, as I said before.

The sound is more "in my head" than on the Sundaras for sure. I can still hear the location of the instruments. I guess that is what they mean by sound stage.

I equalized with Equalizer APO to boost bass (tune everything else down), I get a comfortable rumbling.

For me though, for the stuff I use this for, neither this nor the Sundaras were a pair I would lose my mind over so I guess this is kind of my price limit, for the applications I use headphones for.

Would the Sundaras not have those painful pitches and out of order crackling, I'd kept them. But for the particular items I received, the HD660S is a lot more consistent. I might have received a faulty pair of Sundaras.

I need to adjust the clamp force somehow though. Sundaras were very comfortable, the HD660S clamps a bit hard to me with glasses.

Experience for games, namely Overwatch -

The HD660S sounds exactly the same as the Sundaras, apart from that already mentioned sharp and loud high pitch sounds. I hear everything just as clear around me as with the Sundaras.

For some reason even with boosted bass my el cheapo Plantronics Blackwire has more present bass than the HD660S - could someone recommend some Equalizer Apo settings?
 
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Fregly

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The 650 is too euphonic to my ears with an obvious mid bass hump coloring acoustic recordings, especially orchestral. I replaced it with the 600 and these were superior. The graph on the 660 looks good for what I like in sound, with maybe eq on the bass to make it flat to 30hz. I don't see anything problematic with the treble particularely. Even the bass as it is is more helpful in some music. I really do not get the Harmon shelf and think it messes up the sound royally if added.
 
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