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Superlux HD668B Review (headphone)

aasearles

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Wouldn't you be looking for a pair of headphones with an included microphone for those Zoom meetings?
One idea is to use a Bluetooth module with built-in mic. Connect to the stereo plug on headphone for a wireless gamer/conference headset.
 

Francis Vaughan

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these are like knock-offs of the legendary AKG K-240 Sextett and DF headphones which were all over almost every studio in the 80's.
Ah, I knew they looked familiar.
What is amusing is how they have decided to use a Sennheiser look alike model number. I guess they think that will attract more buyers.
 

Maiky76

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Hi,

Here are some thoughts about the EQ.
Notes about the EQ design:
  • The average L/R is used to calculate the score.
  • The resolution is 12 points per octave interpolated from the raw data (provided by @amirm)
  • The EQs are starting point and may require tuning (certainly at LF).
  • The range above 10kHz is usually not EQed unless smooth enough to do so.
  • With some HP/amp combo the boosts and preamp gain need to be carefully considered to avoid issues
Fair L/R match.
Two HF peaks to remove
LF boost

I have generated one EQ, the APO config files are attached.
Score no EQ: 81.5
Score with Amirm EQ: 88.5
Score with EQ Score: 92.4

Code:
Superlux HD688 APO EQ Score 96000Hz
January082021-102018

Preamp: -8.9 dB

Filter 1: ON PK Fc 30.8 Hz Gain 9 dB Q 1.1
Filter 2: ON PK Fc 176 Hz Gain -1.5 dB Q 0.57
Filter 3: ON PK Fc 1310 Hz Gain 2.5 dB Q 2.36
Filter 4: ON PK Fc 4061 Hz Gain 5.75 dB Q 2
Filter 5: ON PK Fc 5651 Hz Gain -9 dB Q 6
Filter 6: ON PK Fc 8588 Hz Gain -5.5 dB Q 6
Superlux HD688B Dashboard.png
 

Attachments

  • Superlux HD688 APO EQ Score 96000Hz.txt
    340 bytes · Views: 156
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mshenay

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Thanks for the write up! These are indeed excellent headphones, I did a pad swap on them for better comfort and I always forget that I have them lol but they stay with me as my dedicated 3DS headphones when I don't need a closed back for isolation haha
 

pavuol

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Nice analysis & EQ suggestion once again. One have to stop and wonder when seeing sample tracks at the end of the budget product review - was it a mood or is there something special about this hardware? ;) (pleasant tracks indeed)

What caught my attention in the datasheet - "Voice Coil...copper coated aluminum wire". I'd like to ask, is this more common versus pure copper among headphones? (I suppose the reason for this is lighter weight rather than cost cutting..?) Also, manufacturers usually don't specify this do they?

EDIT: they make also pure copper models (pdf hp cat.)
 
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solderdude

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The HD681 is closest to the K240 in construction.
This one also has a B(alanced) and F(rontrow) version which sound different in the bass.
The HD688B (B stands for balanced) has the K240 style cups and AudioTechnica wing style pads. These don't work for me either.
It is also available as other brands (Superlux is OEM manufacturer) some sound somewhat different.
Owned one (and several other Superlux models) before I had a measurement rig.

Typical problems with this headphone (over time):
A: soldered wires onto the headband (right channel cutting out) getting loose.
B: the 'dongle plug' wire breaks after some time of usage at the entry point of this headphone.
C: the point where the metal wires are mounted on the cups by a thick screw have a tendency to break.
 

pavuol

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Another interesting thing about this chinese company is the fact they are not ashamed to mention where they took inspiration with their particular products. In this case they compare its FR tuning to DT990 (not mentioning manufacturer explicitly, but obviously most probably they reference to BeyerDynamic DT990). Pricewise its almost a scandal because for the price of these you can get (roughly) just the genuine velour pads for Beyer`s HP (EDT 990 VB)

2021-01-08 07_12_19-2014-headphone-all.pdf.jpg


I've searched and written down all the references from their catalogue, in case anyone interested:
HD662 - reference to DT770 (most probable to Beyerdynamic DT 770 PRO)
HD662F - ref.to SRH-440 (~ Shure SRH440)
HD662B - ref. to SRH840 (~ Shure SRH840)

HD681 - ref. to HP890 (~ Philips SBC HP890)
HD681F - ref. to AD500 (~ Audio Technica ATH-AD500)
HD681B - ref. to K240 Studio (~ AKG K240 STUDIO)

HD381 - ref. to CX400 (~ Sennheiser CX 400)
HD381F - ref. to MDREX90LP (~ Sony MDR-EX90LP)
HD381B - ref. to MA850G/A (~ Apple MA850G/A)

HD631 - ref. to HDJ-2000 (~ Pioneer HDJ-2000)
HD661 - ref. to MDR7506 (~ Sony MDR-7506)
HD669 - ref. to HD280PRO (~ Sennheiser HD280PRO)
HD668B - ref. to DT990 (~ Beyerdynamic DT 990 PRO)
 

Veri

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these are like knock-offs of the legendary AKG K-240 Sextett and DF headphones which were all over almost every studio in the 80's.


The Sextett were truly something special... broke mine trying to recable them. Still sad.
 

LearningToSmile

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Interesting, this one of the budget headphones I've seen recommended the most few years back before I really got into hi-fi stuff, and almost bought. Instead I went with Samson SR850(which would be sort of interesting to see measured, even if I found them awful - extremely sibilant out of the box, I never tried EQing them though).

It's weird to me that this distortion is acceptable - so it's high in bass to begin with, has noticeable effects after EQ, but in the end it was still not a problem?
 

solderdude

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Another interesting thing about this chinese company is the fact they are not ashamed to mention where they took inspiration with their particular products. In this case they compare its FR tuning to DT990 (not mentioning manufacturer explicitly, but obviously most probably they reference to BeyerDynamic DT990). Pricewise its almost a scandal because for the price of these you can get (roughly) just the genuine velour pads for Beyer`s HP (EDT 990 VB)

View attachment 104452

I've searched and written down all the references from their catalogue, in case anyone interested:
HD662 - reference to DT770 (most probable to Beyerdynamic DT 770 PRO)
HD662F - ref.to SRH-440 (~ Shure SRH440)
HD662B - ref. to SRH840 (~ Shure SRH840)

HD681 - ref. to HP890 (~ Philips SBC HP890)
HD681F - ref. to AD500 (~ Audio Technica ATH-AD500)
HD681B - ref. to K240 Studio (~ AKG K240 STUDIO)

HD381 - ref. to CX400 (~ Sennheiser CX 400)
HD381F - ref. to MDREX90LP (~ Sony MDR-EX90LP)
HD381B - ref. to MA850G/A (~ Apple MA850G/A)

HD631 - ref. to HDJ-2000 (~ Pioneer HDJ-2000)
HD661 - ref. to MDR7506 (~ Sony MDR-7506)
HD669 - ref. to HD280PRO (~ Sennheiser HD280PRO)
HD668B - ref. to DT990 (~ Beyerdynamic DT 990 PRO)

That Superlux list is total nonsense.
The HD688B sounds nothing like the DT990. (owned both, still own DT990)
The HD662 sounds nothing like the DT770 (owned both) They both have boosted bass and treble though. The HD662 is very wooly in the bass, the DT770 is not.
The HD681 sounds nothing like the HP890 (owned both, still have modified HD681)
There is some resemblance between AD500 and HD681F (both are a bit bass shy and trebly)
The K240 studio sounds ver different from K240 studio.
The HD661 looks like the MDR7506 a bit but sounds different. (owned both)
The plots are literally handdrawn and not based on actual measurements of the headpones.
I have several prototypes (including ones that are bound to be released this year) and have their and my measurements and they look nothing like that of the already finished sale brochures.
The same is true for some other prototypes that sometimes differ a LOT from the actual products.
 

DuncanTodd

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Thanks for the review.
I never liked listening to headphones, but circumstances led me to needing one for a few hours a week. Given that, spending much is not something I'd consider. Something cheap that isn't terrible is.
Possible candidates:
Monoprice has some under $50 headphones that I've seen to be quite liked, and for the non-US readers maybe something like the Oneodio headphones that sell in bucketloads on Aliexpress but also available on Amazon.
 
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VulkanApi

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Please describe the difference between 668b soundstage compared to 400i soundstage
 

VulkanApi

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Alternative equalization, the first 1000hz from rtings due to a problem with measuring bass from other sources, further frequencies are taken from oratory1990 and compensated for harman through the auto eq master, in general it measures most accurately, just 668b has problems with bass consistency, on the headphones who do not have problems with consistency, you can immediately put the profile from oratory1990 from the auto eq branch to git hub (400i, hd 800s)
 

Attachments

  • Superlux HD 668B GraphicEQ.txt
    1.3 KB · Views: 92
  • Superlux HD 668B ParametricEQ.txt
    471 bytes · Views: 88
  • Superlux HD 668B.png
    Superlux HD 668B.png
    43.6 KB · Views: 86

pavuol

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That Superlux list is total nonsense.
The HD688B sounds nothing like the DT990. (owned both, still own DT990)
.....
Well I just cited their documents. Thanks for your insight, quality aside (your first comment) it adds another controversy to this brand's HP portfolio.

It seems like we have triple-hybrid in this product ;) ("has the K240 style cups and AudioTechnica wing style pads" + "pretended" Beyer sound)
 
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dukanvadet

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I have these, i think they sound good at low/medium SPL without EQ but when you turn them up it sounds distorted in the bass fast. Looking forward to see the improvement of the EQ but i think i will leave the bass without boost .
 

djigibao

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I have this headphones and add them this Ear Pads (velvet), now they are very comfortable.
They are connected to the FiiO E10k and the Bass option is turned ON.
For that money I think they are the best buy.

Difference: original vs new pads

pads.jpg
 
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