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Superlux HD668B Review (headphone)

Guerilla

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My conclusion from my own experience and what Ive read is that its a good buy, only if you are prepared to use EQ. Otherwise its a confortable (when you get used to it and adjust it right. - posibly by bending a little), but pretty crappy sounding out of the box
 

samwell7

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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.
Where are you based? I'd recommend the AKG K240 studios for around that price, I've had both the K240 and either the HD681B or HD668B superlux (was a while ago) and the K240 was much better, might just need to boost the bass a bit depending on your listening preferences
 

DuncanTodd

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Where are you based? I'd recommend the AKG K240 studios for around that price, I've had both the K240 and either the HD681B or HD668B superlux (was a while ago) and the K240 was much better, might just need to boost the bass a bit depending on your listening preferences
Thanks for the recommendation. I have one of the Oneodio headphones. As I dislike headphones, I could not justify paying more than $30 for something I use for 2-3 hours a week when the house needs to be silent. Are they good? Probably not, but I haven't used headphones in 30 years so I don't have anything to compare to. I have seen the Superlux on AliExpress when I decided to get a pair of cheap headphones, but ruled them out cause I dislike the big arches design.

These AKG240 cost about $88 shipped to here from Amazon and a lot more in local shops (I've seen a few deal places for as low $65 but it's old listings and not sure if it's still relevant). I would also add I don't do any digital streaming (only CDs and LPs), so all those great EQ tips are not really relevant to me as far as I can tell.

What I meant was that these two are possible candidates for popular cheap headphones to test at some point.
 
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samwell7

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Thanks for the recommendation. I have one of the Oneodio headphones. As I dislike headphones, I could not justify paying more than $30 for something I use for 2-3 hours a week when the house needs to be silent. Are they good? Probably not, but I haven't used headphones in 30 years so I don't have anything to compare to. I have seen the Superlux on AliExpress when I decided to get a pair of cheap headphones, but ruled them out cause I dislike the big arches design.

These AKG240 cost about $88 shipped to here from Amazon and a lot more in local shops (I've seen a few deal places for as low $65 but it's an old listing and not sure if it's still relevant). I would also add I don't do any digital streaming (only CDs and LPs), so all those great EQ tips are not really relevant to me as far as I can tell.

What I meant was these two are possible candidates (for what I believe are) popular cheap headphones to test at some point.

Ahh, I understand what you were saying now!
All good, glad you've got something fit-for-purpose.
 

DuncanTodd

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Ahh, I understand what you were saying now!
All good, glad you've got something fit-for-purpose.
Yep, they'd do for my minimal use for now I guess. If I see some resounding recommendation on something as cheap that works out of the box I may consider getting it.
That's the cheap one I got for now (the "Pro 50" version):
https://www.aliexpress.com/item/32790188098.html?spm=2114.12010612.8148356.10.281b3c6e3Eorop
https://www.amazon.com/OneOdio-Adapter-Free-Headphones-Monitoring-Isolation/dp/B01F59T4HU/
I considered some of the Monoprice ones that someone said sounded good to him (he seems to be as "picky" as me), but not being able to tell which he meant + shipping costs tilted me towards the above. It may have been one of these:
https://www.monoprice.com/product?p_id=8323
https://www.monoprice.com/product?p_id=8324
 
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fairx

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I have the superlux evo with velour pad, which itself a variant of hd681. Tried the supplied eq and its good in reducing the brightness and dip in 4k.

And just updated my pi to moode 7 which now I can set up to 12 parametric eq (from 5 band before) . Nicee...
 

solderdude

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The HD681 and HD681EVO differ a LOT in all aspects.
EVO has different enclosure, different driver, different headband, dongle type headphone connector and very different sound.

HD681 EVO (first production run)
hd681-evo-stock-lr.png


for the interested folks (detailed review + modifications) for the HD681 EVO Here's what you can do with it.
 
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L5730

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Can the balance (left-right) be corrected using APO EQ?
Yes!

You can run two different EQ presets, one for each channel if you really want. You can copy some amount of one channel into another. There are loads of things that can be done.

For example, turn down the left channel by 2dB and also add a peaking filter at 4kHz to boost the left channel 1.5 dB at that spot. Leave the right channel alone, no adjustment.
Code:
Channel: L
Preamp: -2 dB
Filter 1: On Pk Fc 4000 Hz Gain 1.5 dB Q 2

Channel: R
Preamp: 0 dB
 

JoeKickass

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How consistent are cheap headphones manufactured? I would be surprised if we can really apply such a targeted EQ to a random pair fresh out of the box and expect the same sound as the pair amir tested, especially the channel imbalance.

I think for a consumer the pre-EQ measurements are really the most valuable and all that most people should be looking at, if you try to EQ with amir's settings your mind could fool itself into thinking it sounds better.
 

solderdude

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How consistent are cheap headphones manufactured?

2x HD681 manufactured about 7 years apart:
old-brown-vs-new-HD681-teal.png


Have modified a lot of those and aside from 1 of them hat had much less bass they all sounded very similar.
 

JoeKickass

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2x HD681 manufactured about 7 years apart:
old-brown-vs-new-HD681-teal.png


Have modified a lot of those and aside from 1 of them hat had much less bass they all sounded very similar.

Ouch there are significant differences in almost the entire response range!

Judging by this curve it looks like any EQ would be fairly counterproductive above ~100 Hz
Unless of course you have an APx555 and can measure the exact headphones you own
 

solderdude

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You only need to EQ the treble peak. This is the same for both models.
There is a slight difference in clarity.

These are 2 headphones, 1 I own (but is modified) the other one is from a friend, that one also was modified.
modified these, no longer $20.- headphones, measure and sound like this (no EQ)
modified-HD681.png
 

sweetchaos

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Can the balance (left-right) be corrected using APO EQ?
Yes, great question.

In the Superlux HD668B review, Amir noted a channel imbalance. He boosted the right channel by +2.5 dB to fix it.
If you want to try this PEQ profile, use this code instead:
Channel: L
Preamp: -11.0 dB
Filter 1: ON LS Fc 30 Hz Gain 4.0 dB Q 1.0
Filter 2: ON LS Fc 50 Hz Gain 4.0 dB Q 1.0
Filter 3: ON PK Fc 4000 Hz Gain 5.0 dB Q 2.0
Filter 4: ON PK Fc 5380 Hz Gain -7.0 dB Q 6.0
Filter 5: ON PK Fc 8582 Hz Gain -7.0 dB Q 5.0

Channel: R
Preamp: -8.5 dB
Filter 1: ON LS Fc 30 Hz Gain 4.0 dB Q 1.0
Filter 2: ON LS Fc 50 Hz Gain 4.0 dB Q 1.0
Filter 3: ON PK Fc 4000 Hz Gain 5.0 dB Q 2.0
Filter 4: ON PK Fc 5380 Hz Gain -7.0 dB Q 6.0
Filter 5: ON PK Fc 8582 Hz Gain -7.0 dB Q 5.0

Based on this idea, I've added this to my main page. :)
update: fixed incorrect pre-amp
 
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djigibao

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Yes, great question.

In the Superlux HD668B review, Amir noted a channel imbalance. He boosted the right channel by +2.5 dB to fix it.
If you want to try this PEQ profile, use this code instead:


Based on this idea, I've added this to my main page. :)

Is this OK (pictures)?

Clipboard01.jpg


Clipboard02.jpg


On the Right channel Peak Gain is 2.5dB in Red.
 

sweetchaos

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Is this OK (pictures)?

View attachment 105451

View attachment 105452

On the Right channel Peak Gain is 2.5dB in Red.

That's ok.
Feel free to ignore that peak gain of 2.5dB.
We know the right channel is playing at a lower volume than the left channel (at least for the unit that Amir tested).
Equalizer APO doesnt understand that, so it's showing you "Peak Gain of +2.5dB" for the right channel.
 
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djigibao

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Maybe is better tu put Left channel on -10,5dB and Right at 8,5db?

Clipboard01.jpg
 

abdo123

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@amirm Apparently the advertised Peak SPL for these headphones is 98 dB, Could this explain the disturbingly high distortion above 96dB?

If that's the case, then it might be worth it to mention it in the review.
 
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amirm

amirm

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@amirm Apparently the advertised Peak SPL for these headphones is 98 dB, Could this explain the disturbingly high distortion above 96dB?
It may but these max SPL numbers are just taken out of a hat. They are best ignored.
 
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