Superlux HD-681 F

I bought this item because it looked comfortable, for long recording sessions. I now have 2 pairs, and bought another for a friend. The headphones are very comfortable, but was surprised that the claimed frequency response appears to be or could well be a fact.

I happened to be building a soft synth in Pure Data one evening, and decided to generate some frequencies to find out what I could hear at 59 years of age. I managed to take the frequency to about 17k and could hear it still through the headphones. That's higher than a Shure SM58 captures.

Nobody at the time of writing has commissioned me to test the Superlux to full verification (20KHz?), but it's easily done if you know PD or Max/MSP, simply generate 20K, then put the recording (with a good condenser mic) into a DAW that has pitch transposition, EG Cubase, then drop it an octave, and see if you get a 10K pitch which should be more audible and checkable against a reference. Reprocessing the signal (wav or whatever) down another two octaves would make the sound clearly audible. Alternatively doing an FFT on the original signal gained or using a spectrum analyser should confirm the fundamental frequency as generated by PD.

In a few words, if you only need headphones that work, practicably, without a big pricetag, I haven't yet seen how to beat these. I have a pair of Sennheiser headphones with a better mid-frequency separation, but they tend to hurt ears after a while.

The F(lat) version of these headphones sound really good. From the first play I noticed a full and surrounding sound. At this price point you probably can't find a better one. Detailed sound and full of dynamics. The bass comes out clear too, even better than the normal version of the HD681. Keep in mind that it really depends on your sound card. A good one will deliver a great sound through the F version.

The included ear pads feel soft and comfortable too. But you can also buy "Superlux HD-681 Ear Pads Velour" for more comfort and premium feeling. These are a bit tricky to put on but worth it.

I use them for video editing. playing piano and VST instruments, audio editing and listening to music.
I used them for playing an electronic drum kit but for that application I got HD-662.

Pros:
- a very clear and and natural sound without bass being too strong
- feel "light" on my head and are very comfortable for long hours (even better then HD-662, which also got 5 stars from me)
- very good build quality for the price point

Cons:
- the low end is not to strong, so this is not a good option if you need a strong bass (e.g. for playing drums - for that application plain HD-681 is better option or closed design HD-662)
- it is an open design, so the isolation from outside sounds is very weak, it is actually an issue if you intend to play e-drums in another applications I tried it was not an issue.