Superlux HD668B Review (headphone)

[ZolaIII]

Not normal usage and a different headphone than the model reviewed

Absolutely the same thing and not a very hard one to fix. However let me further explain. Both cables you get with 668B are rather bad (static picking up) the rubber thingy tiny part of the cable with a jack is only thing which makes them bearable and you really need to invest in ear pads (as those are hard as a rock and hot).

 

[solderdude]

Hmm, same measured bass response as Oratory - wich I simply can't believe to be true. Is it possible that tue Gras just doesn't seal with Superlux pads?

I think the measurements of the HD668b are correct and correlate with other measurements out there and how I perceived them.
The bass deviates because of the Harman target it appears to roll-off sooner than how it sounds (to me) and measures on DF target measurements.
It is a bit sub-bass light and somewhat sharp in the treble in reality as well.

 

[wemist01]

I thought the upper pads were "adjustable" in the sense that they can be pulled out and pushed in to their connecting mounts underneath. So in the image above where we see the cans from the side, the two "dots" above the "L" marker can be expanded to more dots by pulling them out. Mind you, the whole mechanism is fairly stone-age- I'm not saying this helps much at all. But it is "adjustable."

The earcup padding has a plastic feel that begs for replacement. My 12-year-old son claims he likes it fine as-is.

 

[Ron Texas]

It seems that a lot of headphones have a very uneven high frequency response out of the box. Is there a design solution for this behavior?

 

[Rja4000]

@amirm
Do you plan to add some isolation measurements ?

Because that may be an important factor for some applications.

Closed-back HP are meant to isolate (both ways), which has some impact on results...
And not all closed-back will perform similarly in terms of Isolation.
You may find them lacking in some area other, but they shouldn't be compared to open backs...

 

[Blujackaal]

No they can't (MH755) they just act as a slippers to Harman target curve. By the way Superlux is Taiwanese OEM that's why you see so much of they rebrand's on traditional markets.

The MH755 was a $300 IEM that had no QC done to it, it show's more if you EQ it to DF neutral target(Etymotic 4XR). Yet the Superlux seem to do very well despite the drivers seem quite weak like high THD with bass roll off.

It only takes $70 to make a Etymotic ER4S, the rest is high QC and a salary for staff.

It seems that a lot of headphones have a very uneven high frequency response out of the box. Is there a design solution for this behavior?

It measurement limitions, It hard to show anything above 10KHz unless your using TOTL gear. Gras chart's of the ER4S = nearly flat line to 17KHz, Mini DSP ears ER4S = Dips & peaks, only reaches to 15KHz.

 

[BostonJack]

It seems that the use case for adding EQ to, minimally dedicated DAC/Amp units, but even DACs in general, is growing. Perhaps this is the must
have feature for the next generation of devices.
The implementation of EQ isn't hard, but adding a useful UI that makes it easy to use is another matter. Considering the woeful quality of UIs in audio gear, I won't hold my breath on anyone getting this right easily. Auto downloading of EQ settings would be the right answer.

It would be interesting to get a feel for what the requirements for a useful EQ would be. Half a dozen PEQ stages would be a start, but I don't have much of a feel for what would actually be useful.

My impression is that there is room in the XMOS U208 often used (unless someone insists of listening to DSD.) It may not be all that difficult to get the ball rolling here. Moving to a 200 series with even more cores would make things much more easy. It should not add much to the BOM.

Can you recommend an eq software solution? I generally run streaming from Pandora when working, occasionally Spotify. laptop is either Windows10 (work) or Macbook Pro (personal). Something with the PEQ flexibility of Amir's system would be ideal, would settle for less.

Thanks.

 

[sweetchaos]

Can you recommend an eq software solution? I generally run streaming from Pandora when working, occasionally Spotify. laptop is either Windows10 (work) or Macbook Pro (personal). Something with the PEQ flexibility of Amir's system would be ideal, would settle for less.

Thanks.

My post should get you started.

 

[julian_hughes]

I've been an AKG fanboy since the early 90s when I got AKG K240Ms (the original 600ohm version.) I upgraded to 240DF at some point and used those for 15 years or so until they broke.

I bought these Superlux-headphones because there was good reviews online. I was very disappointed with the sound. Harsh and gritty. Nice too see that the measurements confirm what I heard. I quickly gave these to my friend as I couldn't stand listening to them.

I currently have AKG K712s and I'm very happy with the sound.

I gave away mine too, to a charity shop (thrift store in US English?) I just don't need headphones which require EQ & balance correction and then *still* aren't quite right.

Instead I bought a used pair of Sennheiser Momentum (1st gen, circumaural). Now that is a nice sounding closed headphone, requires no correction & is easily driven. Yes, a used one cost 4 or 5 times the price of new Superlux. But I'm not giving away the Sennheisers because they sound great, are beautifully made, and I like them!

Since Amir started doing a lot of headphone reviews this place seems hooked on eq. I think it can be a real mistake to make allowances on the basis of "I can eq it". That *can* work ok on full size kit but most portable/personal playback devices have nowhere near the power required to accommodate a level precut of even a couple of dB. Even a lot of desktop headphone amps are going to run out of power if you need to apply 7 or 8 or 10 dB precut. These are not freakish values!

Life is much, much easier if you buy good quality headphones which fit comfortably and whose sound you actually like!

(edited to correct smartphone tiny screen, tiny keyboard dumb mistakes)

 

[PuX]

In terms of design not only they are knockoffs of AKG K240, they also imitate Audio-Techinca headband.

As for sound, I generally don't get why people bother with these. Yes they are cheap, but everything about it screams poor quality, so not surprised with drivers mismatch.

 

[zberkowitz]

It seems that the use case for adding EQ to, minimally dedicated DAC/Amp units, but even DACs in general, is growing. Perhaps this is the must
have feature for the next generation of devices.
The implementation of EQ isn't hard, but adding a useful UI that makes it easy to use is another matter. Considering the woeful quality of UIs in audio gear, I won't hold my breath on anyone getting this right easily. Auto downloading of EQ settings would be the right answer.

It would be interesting to get a feel for what the requirements for a useful EQ would be. Half a dozen PEQ stages would be a start, but I don't have much of a feel for what would actually be useful.

My impression is that there is room in the XMOS U208 often used (unless someone insists of listening to DSD.) It may not be all that difficult to get the ball rolling here. Moving to a 200 series with even more cores would make things much more easy. It should not add much to the BOM.

I'm working on building something like this at the moment actually, albeit a more DIY approach than a commercial product at this point. It's currently in use in my setup and I hope to get it out there in the near future (source code and documentation). So, glad to see others agree that we need devices with built-in EQ so we can EQ any source with a convenient UI!

It's built on a Rapberry Pi, and the EQ is actually software-based (not a hardware DSP). Digital audio goes into the Pi from an external source (S/PDIF in for now, maybe USB one day), and is processed and sent out to an attached DAC or digital out to DAC of choice. UI is web-based, it's on my home network and I can set EQ parameters in real time from my phone or whatever I have on me.

I think with the UI, I'm going for it to be just flexible enough to implement all of the filters you should need, but simple enough to all exist on one page and allow for intuitive real-time adjustments. Right now that's 10 filters, all can be parametric peak filters and the first and last two can also be shelving or pass. From what I've seen from people like Amir and oratory1990 and the AutoEQ project, that should be enough to do it. I would love to hear thoughts from others on what they'd like to see in a device like this!

 

[the_brunx]

the AKG headband design I guess has a patent on it. but I think the most interesting aspect of the design imo is also implement here with the superlux where they use the two strong metal headband rods instead of wires to pass the + and - voltage to the other side. making the one sided cable headphones very durable and almost immune to headband wire breaks which is a problem which plagues many other headphones using single entry cables (or bluetooth) and thin wires in the headband.

 

[julian_hughes]

the AKG headband design I guess has a patent on it. but I think the most interesting aspect of the design imo is also implement here with the superlux where they use the two strong metal headband rods instead of wires to pass the + and - voltage to the other side. making the one sided cable headphones very durable and almost immune to headband wire breaks which is a problem which plagues many other headphones using single entry cables (or bluetooth) and thin wires in the headband.

I've only ever had one headphone fail in that way, a Sony MDR ZX700 which failed about 3 seconds after its warranty expired I thought "never mind, I can fix this" but when I took it apart it was so flimsy, with such astonishingly thin wires and some really horrible design points that made abrasion inevitable that I gave up right there. I think that was the last full size headphone I bought that didn't have a detachable cable. Mind you, given the choice between a horribly designed Sony and a horrible sounding Superlux I'd go with the Sony and try to work on my rudimentary soldering skills.

 

[the_brunx]

And normally headband pads will not be changeable if they have a wire in them. Big disadvantage. I guess that‘s why most companies chose two sided cable entry.

 

[Jwoooosh]

Being the first "real" headphone I had purchased (back in 2014), I was actually pretty excited to see you review these. I remember finding the soundstage and imaging to be the most impressive aspects with comfort being the primary downside. Overall I would agree that they are still a great buy even today and at a price of $40.

 

[Nango]

A "tear down" of such a Superlux would be nice to see.

 

[solderdude]

Aside from the headband rod shape and the endcap with the dongle wire it looks exactly like the HD681 inside.
The outer side of the cups also has a different pattern in it. The driver looks exactly like that of the HD681 but is not the same one.
A teardown would basically look the same as the modification guide (needs different filter) as the attached pdf.

frontside of the driver is exactly the same as the HD681 (and Samson SR850 is what the picture is from)

 

[Guerilla]

Absolutely the same thing and not a very hard one to fix. However let me further explain. Both cables you get with 668B are rather bad (static picking up) the rubber thingy tiny part of the cable with a jack is only thing which makes them bearable and you really need to invest in ear pads (as those are hard as a rock and hot).

I think you replied to the wrong post. Mine was was a reply to a picture of a broken connector on a different headphone. Ive only used the short cable and ive never heard static. The original pads feels very soft to me, but maybe they were a bit less soft when I got them 10 years ago. Strange to hear soft pads described as ”hard as rock” Are you sure its the 668B model you have?

 

[Guerilla]

@amirm
Do you plan to add some isolation measurements ?

Because that may be an important factor for some applications.

Closed-back HP are meant to isolate (both ways), which has some impact on results...
And not all closed-back will perform similarly in terms of Isolation.
You may find them lacking in some area other, but they shouldn't be compared to open backs...

Are the 668B's closed back?

 

[Guerilla]

From what I've read around, this seems to be the conclusion. A good budget starter headphone in terms of sound after modding and/or EQing. However, I also read that the build, for even the low price that it is, is pretty bad. The argument being that yes it is cheap and not bad after EQ, but just won't last a couple of years.

Interesting review, none-the-less. Thank you.

Its not badly build. Its plasticky because its mostly made of plastic as are most much more costly headphones. I never enjoyed the sound until i EQd by ear and a tonesweep. I would prefer one that doesnt need EQ - Allthough all can benefit some for fitting it to your ears and how you place it on your head. I havent tried Amirs EQ proposal yet, but Im sure it beats mine. Also Im curious to try other drivers in them with less distortion, but Im not sure that would be audibly better.