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New headphones for home and work.


Well-Known Member
I decided to purchase new cans for Home and work and decided on the
Koss Pro DJ 100.

Frequency Response is 10 - 25,000
SPL 99

38 ohms

When at home it has been very good sound and even. Works well with ipod, ipad, as well as into amp or receiver. Comfort to wear is good, with a weight you notice and feel comfortable with, Stays in place without feeling squeezed.

Provides good isolation when in crowded room and loud system running.


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Here's a review from a Head-Fi member. "joker" has a huge review thread which is a good read for anyone looking for a starting point.

http://www.head-fi.org/t/433318/shootou ... ed-10-8-11


Build Quality (8.5/10): Having recently reviewed a number of DJ headphones from big name manufacturers such as Audio-Technica, Denon, and Ultrasone, I was surprised by just how well-built the $80 DJ100 is. Much of the hardware is metal, including the inner headband, rotating hinges, and the outside of the earcups. There is still plastic used on the forks and inside the cups but on the whole the build is quite impressive. The thick coiled cable is on the heavy side but terminates in an iPhone-friendly 3.5mm plug, implying that Koss intended for the DJ100 to be used portably. And of course Koss is willing to back the solidity of their headphones with the usual lifetime warranty and replace the headphones for the cost of shipping should anything go wrong.

Comfort (8/10): The DJ100 is circumaural in size but the cups aren’t very deep on the whole. Clamping force is fairly low and the headphones still remain comfortable for quite a while when worn. A side effect of the low clamping force and loose fit is that the DJ100 is slightly less stable when worn on-the-go than some of the other sets in its class.

Isolation (7/10): The slightly shallow fit limits isolation somewhat but sound leakage is extremely minimal.

Sound (7.75/10): Despite having impedance and sensitivity identical to the ATH-M50 and Denon DN-HP700, the Koss Pro DJ100 exhibits higher dependence on amplification than both - and it’s not just the need for power. Synergy plays a huge role with the headphones and many amps simply don’t mesh well with them. A neutral or slightly mid-centric amp is preferred – I had good results with the Tianyun Zero, iBasso D10 (stock caps), and a mini3. Skipping the amp altogether is a poor idea – the DJ100 only reaches a fraction of its full potential unamped - the ATH-M50, Numark PHX Pro, and even the Denon DN-HP700 sound noticeably better straight out of my portable players. With a proper amp the low end tightens and increases in quantity, the soundstage opens up, and the upper midrange and treble become smoother and less fatiguing. Naturally, the DJ100 does not become a completely different headphone with the addition of an amp but it’s enough of an improvement to make me unwilling to use them without one.

Koss advertises the DJ100 as having ‘Extreme Bass’, which couldn’t be farther from the truth to my ears. The bass is well-balanced and quite linear, with immediate impact and good speed. My well-burned-in set of DJ100s trails the Denon DN-HP700 very slightly in bass quantity and makes the ATH-M50s sound like absolute bass monsters. My usual reference set, the Sennheiser HD25, offers bass that is more tactile, forward, and impactful but also slightly more forward and intrusive than that of the DJ100. The midrange of the DJ100s is completely free of bass bleed but never sounds thin or lacking. In fact, the upper midrange is slightly forward (and becomes more so with the addition of a powerful amp) and most of the headphone’s energy is carried through the mids. Interestingly, the midrange of the DJ100 seems to carry slightly thinner notes than the bass and treble – an odd characteristic for a single transducer but one that makes the headphones sound leaner and crisper. Vocals, especially female vocals, come across very strongly and carry plenty of texture. Those who find themselves easily fatigued by strong upper midrange presence will probably want to give the DJ100s a pass but lovers of forward, slightly resonant vocals will undoubtedly be pleased with the overall balance.

Moving on up into the treble, the DJ100 doesn’t sound perfectly smooth to me, but then headphones with strong treble presence almost never do. It does get slightly smoother with an amp but many of the more laid-back sets still have the upper hand by a mile when it comes to smoothness. Treble clarity is excellent and detail is on-par with the other similarly-priced DJ sets. There is a tiny bit of perceptible treble roll-off at the very top – hardly an issue under normal listening conditions but noticeable in a head-to-head comparison with the HD25-1. On the whole the DJ100 is still slightly brighter and colder than neutral but not distractingly so. The dynamic range is lacking slightly as well – the DJ100 is a bit ‘shouty’ in nature, not unlike a lower-end Grado headphones or the HD25; subtlety is not really its strong suit although it fares more than well enough for an $80 headphone. The presentation, on the other hand, is really quite good for a closed headphone. The soundstage has good depth and width and only gets bigger with amplification. The HD25 sounds positively claustrophobic in comparison. Separation and imaging are good as well but the DJ100 wouldn’t be my first choice for big-band or orchestral pieces. It does work surprisingly well for gaming, however. In addition, the DJ100 is extremely revealing of poor source material – pairing them with an unamped portable player and 128k mp3s is a recipe for major disappointment.

Value (8.5/10). (MSRP: $79.99, Street Price: $80) The Koss Pro DJ100 is a solid mid-range headphone that scores plenty of points for build and sound quality but loses out heavily on portability, partly due to the somewhat heavy construction and low clamping force and partly due to the amplification requirement. There is still much to like about the DJ100 – for a headphone that can easily be found in US retail stores it is priced very reasonably and the lifetime warranty should be a welcome reprieve for those who like to be rough on their gear. As usual, the sound signature won’t be for everyone – the DJ100 boasts tight and controlled bass, mids with a slight peak towards the top, and prominent treble. I think they excel with acoustic and vocal-centric tracks and break down with hard rock and metal, for which they really don’t have the correct tonal balance, and big-band/orchestral pieces, which benefit from a less aggressive presentation. With that in mind, the Koss Pro DJ100 extends the bang/buck of the other Koss headphones featured in this review to a whole different price range – a great proposition for budget-conscious buyers.
Thanks for that review Dane.
malsackj, that review states that these headphones need an amp. These are rated 38ohms. When connected to a portable device , do you find that they need an amp ?
Just checking around...
Barney said:
Thanks for that review Dane.
malsackj, that review states that these headphones need an amp. These are rated 38ohms. When connected to a portable device , do you find that they need an amp ?
Just checking around...

Is that 38 Ohms or 380 Ohms? 38 Ohms should be easy to push. My K107s didn't seem to strain when being driven by my CD changer (that has a variable output) and they were rated just a little over a 100 Ohms. The K240DF were another story (600 Ohms).
it is 38 ohm and I found that I can run very well from Ipod, ipad and computer.

When on the mixers it has a good sound also. I did not notice any difference between computer and mixer. Presonus studio live 24-4-2, and my EV M4 mixers. We were working in a loud show as Pauly will verify. Richards gigs are body shakers. 2 18's per side and mains are 2 15 with horn. triamped with 20,000 watts crown amps.

I also connected to the amp in the house. Sansui B-3000, Sansui C-1000, toshiba Blueray player.
I like a more laid back moderate sound, that would explain his review differences. Along with most of my time on mixer was with a pounding system. Can't judge base response with 4 18's running in the room. They work better for isolation and they don't distort or overload easily on the mixers or the amp. The smaller cheaper Sony, AT, 30 dollar headphones found otherwise were easy to overload and distort. They had smaller pads and lighter construction.
2 18's, 2 15's...20K watts, are you some kind of party animal? :laughing-lettersrofl: :music-rockout:
Just enjoy the tech and work. We will be out for haloween and running more dmx lights.

We will be up in baltimore. We even get paid to make the music loud .
Seeing the article on the head gear inspired me and I took a piece of plywood and cut a small hole to allow the Behringer 8000 microphone to fit in and then placed the headphone on the plywood to create a seal over the mic. Then ran the pink noise test with True RTA and have captured the result with the picture below.


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The output amp was the m-audio Quattro that also provided the microphone input.

No equalizaiton going on on in or out.
Cool! Never tried doing RTA of headphones before...
I purchased at home depot the pine. But I had my gear on a granit slab to reduce the vibrations and jitter.
I tried it initially with out a seal for the cup and the result was a loss in the 200 hz and below.

I also had to ensure the board allowed some space to get the complete open ports on the tip exposed and prevent the tip from hitting the protected cover inside the cup.

If you expose only the tip of the mic you will be changing the omni patern to a cardiod and might create an exagerated base response.
I made my post semi-in-jest, but I have to wonder how much the phone sound changes due to different people's ears, the exact position of the phones on the ears, hair, etc.
I think I posted something about professional ear cleaning (something I have to get done once every four years or so) and how much it changes how things sound, not just speakers/phones but just everyday life. Something else I've been wondering about the past few years, how much "treble response" is being masked by my now-noticable tinnitus... :|
Yes the jest was fun. the granit slab was fun too. I dont think a small headphone driver would be able to generate a accoustic response from half inch pine unless It happend to have a really bad void or knots. I considered 5/8 MDF with a special with an added 5/8 MDF Ring to help seal the cup but the pine was available at the house. Routing and hole saw would have tacken time and the test for the single headphone was not needing tremendous testing.

One thing that does bother me on this test is the response above and below the magazine results. Making me wonder if my test was flawed or theirs.

Maybe I should make a good MDF test rig to run up by Pauly and Bat and test the headphones available with various amps.
That would be fun! Though I really only have a single set of over-ear headphones right now (my modded Denon D5000)...
Ok I will run by hardware store and get a small 5/8 mdf and will cut the 3/4 inch hole for the inner ring. Then cut the outer ring at about 2 1/2 inches. Would this fit the cup seals OK.

Question for the acoustic people would be with the 3/4 inch hole be Ok or would this skew the results? Should I make the hole larger and closer to the cup size to prevent creating a pressure zone like the throat for a horn.