[timetolose]

The HD660S2 has the same ohm rating (300) as the 600 and 650, so if those sound good to you the 660S2 should be no different. I actually prefer the S2's to the the 600's, 650's and 660S's.
Of course we all hear differently.

I think they will scale up with a desktop system, but will sound good with your Mac if the 600's did.

PS: The S2's sound great on my tube amps that don't put out a lot of power (Schiit Valhalla 2 and Little Dot MK9).

I hope this doesn't derail the thread too much, but regarding the different impedance I was referring to this post. I remember reading elsewhere that with dynamic drivers, the impedance generally increases towards the lower frequencies, so my concern is that even if the overall volume is high enough, the bass quality might suffer with amplification that is just "kind of ok".
The FT5 probably doesn't have this issue, as iirc planar drivers have a constant impedance across the spectrum. Although, since the FT5's sensitivity rating is lower, shouldn't the 660S2 be actually easier to drive as long as the amp can provide enough voltage?

Also to move the thread back on track a bit, the FT5 was the first planar I've ever had on my head. I didn't expect there to be that sensation of positive and negative air pressure and audible diaphragm crinkling when putting them on or even just slightly lifting a cup off an ear to adjust the position (with the leatherette pads), which is why I returned them kind of impulsively and disregarded the things I liked about them
I don't really see this effect mentioned or discussed anywhere (aside from Audeze's PSA). Is this unique to the FT5 or something that you just have to accept and deal with in the planar world?

 

[Shane D]

I hope this doesn't derail the thread too much, but regarding the different impedance I was referring to this post. I remember reading elsewhere that with dynamic drivers, the impedance generally increases towards the lower frequencies, so my concern is that even if the overall volume is high enough, the bass quality might suffer with amplification that is just "kind of ok".
The FT5 probably doesn't have this issue, as iirc planar drivers have a constant impedance across the spectrum. Although, since the FT5's sensitivity rating is lower, shouldn't the 660S2 be actually easier to drive as long as the amp can provide enough voltage?

Also to move the thread back on track a bit, the FT5 was the first planar I've ever had on my head. I didn't expect there to be that sensation of positive and negative air pressure and audible diaphragm crinkling when putting them on or even just slightly lifting a cup off an ear to adjust the position (with the leatherette pads), which is why I returned them kind of impulsively and disregarded the things I liked about them
I don't really see this effect mentioned or discussed anywhere (aside from Audeze's PSA). Is this unique to the FT5 or something that you just have to accept and deal with in the planar world?

I am currently wearing my FT5's and have not come across any crinkling at all. I recently had a pair of planar's called the Bee's from Nectar Sound and they crinkled as soon as you looked at them. Very off-putting.
My other set of planar's are HiFiman HE6se V2's and I don't find it much there at all. Maybe a bit when putting them on or taking them off.

I get what you are saying about the power required. A headphone like the HD660S2 will not sound its best if under driven. I do find them surpringly easy to drive, but I only use desktop amps.
I certainly wouldn't be using either headphone with a phone or a dongle.

My set-up is my laptop acting as a "jukebox" feeding a Schiit BF2 DAC feeding multiple amps.

When I go mobile, I use my Koss KPH30i's. Great with my phone/dongle or my DAP.

I have NO planar crinkle on my FT5's.

Neither headphone needs a lot of power, but I can't speak to a Mac as your source.

 

[timetolose]

I have NO planar crinkle on my FT5's.

Argh, just as I thought I could decide for the 660S2, it seems I might have to reorder the FT5.
I didn't think my set was actually defective, since the effect seemed very close to what this guy shows here. I of course didn't do what he does there, but I have no doubt I could have provoked this effect on the FT5 I had.

 

[dpump]

You should never put your hand on the earpad forming a seal and push toward the planar driver. You should also never push on the earcup from the outside when you are wearing the phones. If you do either of these you are forcing the planar driver into the magnets and you can damage or rupture the diaphragm. Audeze specifically warns against doing this in their literature. The guy in this video is obviously clueless as to what he is doing.

 

[timetolose]

You should never put your hand on the earpad forming a seal and push toward the planar driver. You should also never push on the earcup from the outside when you are wearing the phones. If you do either of these you are forcing the planar driver into the magnets and you can damage or rupture the diaphragm. Audeze specifically warns against doing this in their literature. The guy in this video is obviously clueless as to what he is doing.

I know and I didn't do it, I just meant that I experienced a less severe version of this with the set that I returned. It was so bad that when (carefully) repositioning an earcup on my head, the sound would briefly cut out completely. Having no other experience with planars, I assumed that it was something that you just have to live with (either on just the FT5 or on planars in general).
@Shane D sharing that his set doesn't exhibit this behavior was the first thing that made me even consider that my set might have actually been faulty.

 

[Shane D]

I know and I didn't do it, I just meant that I experienced a less severe version of this with the set that I returned. It was so bad that when (carefully) repositioning an earcup on my head, the sound would briefly cut out completely. Having no other experience with planars, I assumed that it was something that you just have to live with (either on just the FT5 or on planars in general).
@Shane D sharing that his set doesn't exhibit this behavior was the first thing that made me even consider that my set might have actually been faulty.

The sound cutting out completely would have been the clincher for me. Definitely a bad set.

 

[politel]

@timetolose
Last summer I was looking for a replacement or addition to my K702 and came across the new HD660S2.
After testing for a while, I noticed that both headphones sound very similar. Both headphones are very bright and work like a scalpel that breaks down the music.
The sound was identical on both the strong desktop amp and the good dongle. Or maybe I have wooden ears?

While the stronger bass is an advantage for the HD660S2, the difference between the two was too small for me to spend €500. An EQ helped the K702 very well.

The FT5 is designed completely differently. It is noticeably gentler in the highs and has stronger bass. At first glance it seems a bit gloomy. But in my opinion it works very well on many music genres and better than K702/HD660S2.
I find the FT5 very comfortable for artists such as Loreena McKennitt or Sting. The voices are very good and lively. I can also enjoy the FourPlay CDs for hours.
Another difference can be heard, for example, in some recordings of “Schiller”. With the AKG and Sennheiser I often had the feeling that some recordings were clipped and the highs were screaming. With the FT5 you don't hear any of this and everything is reproduced cleanly and relaxed.

Personally, what I like best about the FT5 is that it has the same sound signature as my Nubert speakers. It's like having your head stuck between the speakers. But that is individual taste.
And: The FT5 is solid and perfectly made of metal. It's a pleasure to pick it up and put it on your head. A pair of headphones for eternity?
Only the cable is a bit short for me at 1.4m.

 

[ballard3]

The cable indeed would be too short for my desktop set up. Any suggestion for a good quality extension cable?

 

[politel]

The cable indeed would be too short for my desktop set up. Any suggestion for a good quality extension cable?

Yes, see this:
AliExpress >> FiiO/LL-RC Dual 3.5mm Interchangeable Earphone Plug Upgrade Cable >> FiiO LL-RC

 

[Ichos]

Full FiiO FT5 Review is now available in my website.

 

[Shane D]

Full FiiO FT5 Review is now available in my website.

Nice write up! Just finishing day 9 on them. I will be going for a radical change tomorrow.

I am Really curious to see how I react to them in several weeks when they go back on. Very happy so far.

 

[Filodream]

I had a quality control issue with my FT5s which I sent back to Amazon for a refund. Something in the right cup was moving and creating a metallic rattling every time I moved my head.
After an inspection I discovered that it was the pin in the photo. It had a lot of slack in its seat and there was no way to fix it.
Really bad..

 

[00headphone00]

I just bought the FT5. Up to now I am very amazed by them.

For more than a decade, I had and still have the HD650. These suited me very well, I really like the very natural sound of them. They are extremely neutral with a slight warmth in the mid bass. The combination of the slight warmth and the highs that are very clear and detailed without being sibilant or grainy at all makes them so great with nearly everything you listen. These characteristics also makes them very hard to beat, especially the upper mids and highs.

Although the hd650 is great, I (and probably many people here) are always wondering how a improved version would sound for me personally. For me an improvement over the HD650 would be a wider sound (not so much between your ears but more around you), a fuller low end and even more detailed and fast highs while remaining the smooth and grainless character.

I tried a lot headphones, but neither really impressed me. They were either just not big enough of an improvement or just plain lacking on some points. The biggest dissapointed was the HD660S2, with I found the worst "expensive" headphone I ever heard.

Up to I found FT5. It does exactly what I looked for in a HD650 upgrade. a very full bodied sound that's wide and fast.

The FT5 has the same kind of mid bass as the hd650 but the bass is deeper, fuller and warmer. People who won't like the hd650 for their "bloath" won't like these probably as it's really that but more extreme.

Its also a mid forward headphone making voices sound full and present. The upper mids are a little less present than in the 650. The highs are fast and detailed, like most planars. It's mostly smooth and grainless, although it's a bit darker than the HD650. It's far from dark like an Audeze LCD2C, but it's defenitely a little bit darker than neutral. I don't mind as it still sounds natural, but some that like a really neutral sound, its something to keep in mind.

The best thing is the soundstage, despite the warm tone they sound wide and lively. I always thought that this is only only possible with a very analytic sounding headphone like an HD800, but I am very suprised these FT5 can sound very wide and "around your head" while having a warm and full sound.

I really recommend these if you like the HD650, but want something that's fuller in the bass, or wider sounding without giving up on the neutral character. It sounds like a warmer and wider HD650.

Some comparisons I made:
LCD2C
My first try in the search to a upgrade. I love the wide soundstage, the "around your head" experience compared to the HD650 that gave an "in your head" experience. I didn't liked the mid-highs at all, it's extremely recessed like there's a big hole. Also the bass was very disappointing, it goes lower and is faster than the HD650 but it's very thin. I found it a bit of a cold sound. It was the fastest sound although.

HD660S2
I compared this one directly with my HD650 with new original pads on the same dac/amp. It sounded terrible, especially the highs are very metallic. Less sub bass, more boomy mid bass and a very small soundstage (much smaller than the hd650). Its by any margin the worst headphone I heard in years from a well known brand. I cannot believe this belongs into the 600 series . . . There are 100 dollar headphones that are much more true to the source and natural sounding. Not a slight warm and inviting sound as the HD650 or very technically correct HD600 at all.

Hifiman Ananda
More V shape sound. Tighter and harder bass with more impact. I found them a little too much in the bass. Tje highs are more pronounced but in a good way, the highs are extremely clean, free of sibilant and sharpness. Just very present. I missed the warm mids from the FT5

Moondrop venus:
More like the Ananda but with sibilant and sharp highs. Very detailed.

 

[00headphone00]

Double posted

 

[jeromeoflaherty]

Looking at the latest headphones.com video about the Modhouse Tungsten - if you look at its frequency response I think it's very similar to the FT5. Couldn't find the Tungsten FR on any squig.link yet but I would guess it's very similar except for the upper treble.