Prelude​

Note:
Please do not read this review if you’re short on time, don’t skimp.
The HD660S2 is not a one trick pony.
Save this review in your bookmarks and read it on the train or in bed at 2am.

Audio gear has been an addiction of mine since I was 14, and I remember undergoing 4 months of research to find a headphone that will beat the Dr. Dre Beats Studios for half the price. Many days of going back and forth between many choices I landed on the ATH-A900x and to this day it still sits on my rack. I soon fell into a rabbit hole of headphones and finally considered the HD600 as my endgame for the past 6 years as I creeped into the age of 28. At this point my listening preferences have solidified and I’m no longer flexible with new sounding equipment. I’ve purchased other brands such as Hifimans to Beyerdynamics with an open mind but they have all been returned.

I’ve been satisfied with my inventory, until well, Sennheiser sent me an HD660S2. I am still unsure of what I’ve done to deserve them, but I’m grateful for having been given a pair. Do note that the following review will be as critical as if I were to purchase the headphone myself. This is the only time Sennheiser has ever sent me anything and I do not expect them to send me anything else, with that in mind I will be following up with an honest review to the best of my abilities as I would for any other headphone.

The reason I’m so picky with gear is that I’ve come to realize after many headphones, the HD600 is the absolute one especially when it comes to mids. The headphones are able to recreate the intricacies of vocal qualities. Such as chesty to breathy vocals, the ability to present vocalists’ tongue and teeth placement, and I use all that information to create a mental rendition as if I were that vocalist in front of a microphone. I love hearing piano keys actuating hammers that strike the strings of a grand piano, creating a ground for a violin to cry and soar into the highs of triangles and cabasas into the empty void of white noise. The Sennheiser HD600 has done this for me for half a decade now, and the HD660S2 is challenging for the oval crown.

On another note, my analysis on the HD660S2’s may seem overexaggerated compared to the average listener. I’ve been told before that X headphone sounds fine, or Y headphone sounds fine, or X and Y headphones sound similar. Which is fine, I’m not one to judge another's perceptions and perspectives to differentiate between gear, but please again do note that my review of course be taken with a grain of salt.

I also play a lot of games semi-competitively. CSGO/Squad/Insurgency, and I listen to Jpop(rock), Kpop, Pop, classical and almost anything involving instrumentals. Majority of my music cannot be found on Tidal, as my listening preferences are found on the asian market.

I see headphones as tools. I put on the HD600’s for music, and the HD660’s for gaming. I don’t switch to X headphone for X song or Y headphone for Y song. That has changed though. Nowadays I use the HD660S2’s for almost everything, as I now have this temptation to bring the HD660S2’s to my bedroom computer setup and the HD660S2’s to my living room setup. Every other headphone seems to have taken a step back and they don’t get my attention as much as the 660S2’s. Before we get to the gritty details, I’m going to start off the review from the very beginning of receiving the HD660S2’s.

It’s day 1.​

The headphones are still in the box, and a rather small one, and they’re in the exact same packaging as the HD560S. Well that was an unpleasant surprise. I’m going to miss the hardbox of the original 660S’s or HD600’s. It’s a shame really, I was quite disappointed by the packaging the S2’s were delivered in. Well, Sennheiser better deliver on sound, because taking out the headphone I’m also greeted by the exact same appearance as my HD660S, save for the bronze accents of the HD660S2. Financially though at least in the long run the S2’s will last at least a decade, as it will be easier to swap in all the other parts from my other HD6* headphones. The official earpads themselves are also available on amazon which is fantastic. As based on hours of swapping earpads with former Sennheiser headphones, no other earpads come close to the original earpads that maintain the original sound I have come to enjoy from their headphones.

Regarding the initial clamp, it’s quite aggressive on S2’s, and this actually hinders my ability to listen to music like my prior Sennheiser headphones where I only focus on the sound. Though the S2’s may clamp, I actually don’t notice any hinge creaking that the HD660S’s had which is great, so that’s a definite improvement. Although I will come back in 2 weeks where the clamp is less aggressive on my ears. I instead decided to opt for a sound source where I could get immersed and focused on something else.

Starting with gaming.​

Opening up discord and immediately being greeted by a few dudes in a VOIP channel, the first thing I noticed was the HD660S2 being absolutely clear for speech. This is great, because in this game I play on a daily basis called Squad, I always take up the role of a Squad Leader. The Squad Leader is essentially a volunteer managerial position where I need to listen to 2-4 voices through my right ear, speak with fellow squad leaders with my left ear, and have a 3rd party application like Discord taking up my center channel.

So was I able to differentiate between voices better than the HD660S or HD600? Yes. The only issue remaining was dealing with information overload. My brain trying to comprehend everyone at the same time and reply to each person in the correct order was a task in itself. Needless to say, whenever I’m in the zone I can reply back to every single individual with ease. Much easier than any prior headphone I’ve owned before.

Speech separation is great on the HD660S2.​

The HD660S2 also features more accurate imaging than the original HD660S. The HD660S’ imaging was already spectacular and laser sharp. I never struggled with pinpointing the location of gunfire based on audio positioning. But now it’s even better. The HD660S2 solidified the center image, and filled in the soundstage with multiple layers for center imaging. I no longer require turning my head of my game character to confirm if the gunshot came from in front of me or behind me. A short preview on tonality for later, the HD660S2’s treble is absolutely realistic, the bass is well textured and mids clear. Add this into the amazing imaging and everything sounds clean. I can look at a vehicle with its rumbling engine, or if a vehicle is on fire I can practically feel the .ogg file just radiating off it.

Sound presentation is great on the HD660S2.​

Forwarding the time to two weeks of ownership with the HD660S2’s, the clamp has finally loosened. If they are anything like my other Sennheisers, it will take about another month for them to adjust to the size of my head. So regarding comfort it will be a total of two months for them to relax and feel better to wear. I do want to point out however that Sennheiser’s oval cups and headphone design itself are the absolutely most comfortable out of all headphones I’ve tried. They are lightweight, they conform to my ears, the swivel cups are spectacular, and the earpads are just the right density.

Let me rephrase my statement from before, since the earpads and headband pads are the same as any other Sennheiser 6 line, these parts are absolutely modular and I have no issues finding them anywhere else on the market. So I don’t doubt for a second that long term ownership is without a doubt in my mind with the S2’s

The other thing I’ve noticed is that the HD660S2’s have a shorter cable than the HD660S’s, and I’ve grown fond of bringing the S2’s with me everywhere I go now. The HD660S’ longer cable 3m cable was great for walking around, but the HD660S2’ 1.8m cable I felt was a lot more manageable to have instead.

​

Daily Comfort and Build Quality is spectacular on the HD660S2.​

So with that we’ll get into music.​

The HD660S2’s have gotten past the grace period and my brain has fully acclimated with S2’s, they are past the new toy syndrome. So let’s get into what it’s like to get into the HD660S2’s after never having experience with higher end headphones. I’ll be honest here, and at the time of writing, HD660S2’s are a tier up from the entire HD6** lineup and it all comes down to microdetails. Anything off to the side of the far edges of the given soundstage is solid and I have zero issues tracking those instruments.

With all other headphones it seems as though instruments would fade away into the distance. Instruments with the S2’s would exist in its own space and direct all their sound towards me in all of its clarity. Instruments in general have greater detail than my other Sennheisers and it gives them that extra bit of realism. Any reverb near the end of a song can be heard, and artists that sneak in a small vocal line are audible. I don’t need to increase my volume to hear it; no detail escapes the HD660S2’s. I’ve never heard detail like this before, and it just blows my mind listening to songs that I had in my library for over 5 years.

HD660S2’s microdetailing and intimate soundstaging is mind blowing.​

Let’s get into tonality starting with treble. The HD660S2’s bring out a smooth and realistic presentation. I can’t say for sure but they could be on the same volume as the Sundaras regarding treble, but they peak in the absolute perfect place in comparison. Sundara’s treble is somewhat grating for me and peaks in the weirdest places that seem to alter speech. Listening to that guy on AfterPrisonShow with the Sundaras is a real problem, I can’t stand listening to him with the Sundaras as the lower treble peak on the headphones emphasize the way he pronounces “S” sounds through his molars. I’ve sold the Sundaras a long time ago and my goodness just typing about that headphone brings me grief again. The 660S2’s treble regarding speech on S pronunciations are smooth in comparison, there is no grain and sibilance.

​

I digress, let’s go back to the 660S2’s treble. Got off topic there.​

The S2 has smooth and delicious treble for high hats and higher pitched instruments. It's done completely different compared to the 600, 660S and 560S. And it's realism. There was an odd familiarity to high hats with the 660S2. High hats in real life aren’t all smooth and sparkly like the HD600, they’re not sucked out and sparkly like the 660S, they’re not splashy and grainy like the HD560S.

The S2’s treble is clean, well defined and solid, they produce air when two cymbals separate. So when a drummer separates two cymbals and taps the top of a cymbal the first thing I hear is the tap, the next thing I hear is the top cymbal dancing on the edges of the lower cymbal and it just constantly creates air. It’s aggressive, and a beautiful evenness between the top and lower treble is where the treble on the HD660S2 takes the cake. This is not to be confused with the HD600’s higher placed treble on the frequency spectrum, the HD660S2 takes a middle approach. Treble extension is absolutely there but not as pronounced.

Well how does the treble on the HD660S2’s perform with the highest of frequencies? If anyone is familiar with synthesizers with jpop and kpop; the artists do not let off on these. They will sweep synths from 7khz all the way up to 14khz and sweep these tones from the left to right channel. Tracking these made me smile as the S2’s are absolutely quick and I can tell if the synthesizers are square or sine waves. Just for giggles I ran a frequency sweep from 20hz to 20khz and apparently I can still hear up to 19khz and feel 21khz. Cool! I used to be able to feel 22khz on an AKG Q701 back when I was 18 but you know what, I’ll take it, good to know my hearing isn’t completely smashed, lol.

The treble on the HD660S2 is absolutely fantastic.​

Admittedly I am not a bass-head, maybe sometimes. I don’t desire oodles amount of it as I am a stickler for bass-bleed. If anything touches my mids you will for damn sure be notified of it. I will inform you of that in a moment but bass comes first.

The HD660S2 has extension and punch. I’ve done a bit of Oratory EQ on the HD660S and I would say the Oratory HD660S is on par with the HD660S2 strictly regarding sub-bass extension. For detail they’re about the same for the Oratory HD660S too. Remove this EQ though from the HD660S and they’re back to sounding rolled off by quite a bit. The HD660S2 extends, punches, and is naturally filled with bass detail without needing EQ. Compared to the HD560S, the HD660S2 has more bass presence and detail by a long shot, it’s not even a competition. The 560S also somewhat lacks that punch as well that the HD660S has. When listening to a heartbeat on an HD660S2, I can hear the flow of blood, ventricle valves opening and closing, the resonant heart thump is all laid out for me. The other Sennheiser headphones don’t really portray this sort of detailed emphasis.

Sundaras are definitely left in the dust, if they couldn’t touch the bass weight of the 660S’s, then they definitely can’t touch the 660S2’s.

Bass is great on the HD660S2.​

If you have been skimming past the wall of text.​

You need to read this word for word when I speak of the mids for the 660S2’s. Senny fans who are all about the mids, if you came from the HD600’s, HD660’s or HD560’s; read closely.

• The HD560’s mids are linear and clear. They just get cut off by their sibilant and grainy treble that occasionally hinders them from a totally smooth vocal presentation.
• The HD600’s mids are warm, smooth, engaging and airy. Yes the upper mids can be slightly aggressive but if you pair the HD600’s upper mids peak with the right solo vocalist, you will be floating in an intimate void of smoothness.
• The HD660S mids are warm, flat, intimate and aggressive with plenty of detail and spectacular vocal separation. Not clear like the HD600’s and HD560S’ though, but if you want to have fun with multiple vocalists the HD660S is the one as the smoothed out and even upper mids allows you to pick and choose the vocalist you would like to listen to.
• The HD660S2’s mids are clear from the middle of the mids, like 300hz-ish, all the way up to the 3.5khz area and are linear like the HD560S. They also feature that technical ability of the HD660 that allow you to selectively listen to individual vocalists.

This is where it stops though.​

The 660S2 has lower mids that are slightly thicks on some tracks, and the upper mid extension is somewhat shorter in airy extension past the upper mids peak. The peak of the upper mids are solid, whereas with the HD600, this upper mid peak is more on the airy side. So no, you won’t be getting the full midrange experience of the HD600 with your solo vocalists.

BUT, HOLD ON. ​

Remember this is the Sennheiser HD660S2, and I said the center imaging on the 660S2 has been improved with more layers over the HD660S. If solo vocalists weren’t your thing, then mayhaps I interest you in tracking harmony vocals? On a track where the harmony vocals are practically cheek to cheek with the main vocalist, you will be able to hear each of them clearly. This is where the lower mids of the HD660S2’s come in, because the clear and lower and upper mids create such a stark contrast for higher and lower octaves that it plays well for vocals. To put the vocals of the 660S2’s in a nutshell. The 660S2’s give up some of the HD600’s vocal air and smoothness, for clarity and technical ability with instrumentals. Although I personally prefer vocal tonality at the forefront of my gear before all else, which is why I’m so picky regarding midrange performance.

I am still conflicted that my cute japanese vocalists don’t get the high upper mid extension though, but it’s not as bad as I’ve described. The HD660S2 has this thing of making everything else sound so wonderful that I find it okay that vocal tonality took a slight step back.

Vocals are an interesting rollercoaster with the HD660S2’s.​

So let’s sum it all up.

• HD660S2’s are the absolute best for instrumentals and present them in an intimate fashion.
• The Treble is absolutely fantastic.
• Bass extends, kicks, full-sounding, best bass in a Sennheiser I’ve heard so far.
• Mids, in every step of the way they are a step above in technical performance
• Tried and true design that the Sennheisers are known for since forever.
• Gaming headphones, forget the competition, this is it. 10 hour gaming sessions no problem.

I’m now almost a month in with the HD660S2’s, my least used cans will stay on the rack, and the headphones I rarely touch and don’t regret letting go will be sold at a garage sale.

In this case:

• The HD560S are a sell.
• The HD660S are a sell.
• The HD600 is a complementary keep for the spectacular HD660S2.

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Extra Stuff.​

Source: JDS Atom Stack in 1x gain, averaging 12 o’clock volume dials.
Look here man, the stack has done me good for 5+ years.

And again, thank you Sennheiser for the 660S2, best gift I’ve received this year outside of my cat bringing me a dead guppy from my fish tank, both were unexpected.

If you have questions about the HD660S2's, DON'T ASK.
I will proceed to crawl back into my cave and enjoy my music and games.

Thank you everyone for reading and for sticking with me on my lengthy review of the Sennheiser HD660S2.

See you all in a decade,
Smugsie

There's not much to say about the H180's, there's a few downsides like a slightly bloated mid-bass and a treble that's a little plastic sounding. However after 10-15 minutes of listening my brain adjusts to it, and when switching off to other earbuds I end up liking the H180 much more. True, the cable is very reminiscent of 2010 standard earbud cables, but they're not bad, they just don't feel durable. Also the cables attached to the earbud don't feel very secure, a decent yank will most likely destroy these earbuds.

They're not the most durable, but if you want to ever use these to sleep on your side with, the H180's would be it, they sit flush and don't stick out like most earbuds.

The full sounding nature of these and the way it presents music makes me play these at lower volumes. Earpods, airpods, nicehck b40's in comparison I tend to increase the volume on as they sound leaner and don't present as much bass as I'd like. True, I do

These also isolate sound a decent amount when playing music. I don't exactly want to shut myself out in the office if someone calls me, but people speaking around me are instantly drowned out.

So yes, buy the H180's, white or black; whichever one is cheapest.

Disclaimer: The IEM was generously provided to me by KB Ear, however I will treat the product as if I purchased it with my own wallet.

Let's jump straight into the review. Other users have posted magnificent photos so look at theirs instead if you want a visual tour of the earphones.

Music (Specialized)

When it comes to music, the KB Ear KS2 is an IEM that excels at bass oriented music with low treble presence in the mix and no vocals. Specifically Lo-Fi. All other genres out the window!

Bass (10/10)

Upon first listen on the KS2’s, the bass immediately stood out. It was like I was discovering car subwoofers again, the surprise on my face definitely showed, there’s no way I was keeping a pokerface when it came to the KS2’s bass.

The lowered emphasis on mids makes room for the bass to shine through in all its’ glory. The bass region effortlessly sweeps through 20hz to 100hz with authority without bleeding into the mids. Personally, the KB Ear KS2 beats my Planar IEM; the Audeze iSine 20, 500USD MSRP out of the box when it comes to bass. It even beats other IEMs like the Sennheiser IE80 250USD MSRP when the bass dial is maxed out. If you’re a basshead, reduce the treble peak at 8khz by -5dB to -10dB and crank up the volume.

The KS2’s bass detail is quite impressive, I can feel the drivers pushing air into my eardrums with no distortion and there’s some decent punch accompanying it. Not only is there’s decent bass quantity, but bass quality too.

Mids (6/10)

Every other genre is thrown out the window as the mids feel thin, compressed and peaky due to the slight emphasis on some parts of upper mids. The IEM’s can present vocals but this is not what you buy the KS2’s for. Given how expansive the soundstage is, I thought the KS2 would do well with Orchestral or Classical music. Unfortunately violins are screechy and the thin mids take away the magic of the majority of string and wind instruments.

Out of the budget IEM’s I own, I prefer smoother mids, whether it be darker like the FAD E3000 or brighter like the Tin T2.

Treble (5/10)
Forget vocals, forget snares, the KS2’s treble might make your ears bleed if you play the wrong track. Stick to Lo-Fi and you’ll be safe.

Although I’d like to mention one thing. Reduce the treble peak at 8khz by -5dB to -10dB (depending on preference) and you’ll discover a subtle sparkly top end. I didn’t discover a sparkly top end until I had to pay 300USD for a Sennheiser HD600, but hey I guess you can find sparkly treble for 35USD now.

Micro-Detailing, Soundstage, Imaging, and Gaming (8/10)

The KS2 does not sound like 35USD when it comes to soundstage. I’ve used these for a semi-professional tournament in an FPS game called Squad (on PC) and the positional accuracy and distance for gunfire was like it came out of my Audeze iSine 20’s. Micro-detailing exceeds my expectations too, it may not sound like there’s much due to the amount of sub-bass, but it really shows in tracks that have multiple layers and the KS2 successfully shows technical prowess here. I’m not comparing the KS2 to budget gear so keep that in mind when I say the KS2 is technically capable.

Amp Scaling (It sort of does)

I was told the KB Ear KS2 are to be driven off mobile devices, and they are right! With more power comes more bass, but the treble end also lifts with the bass. I felt much more comfortable just plugging the earphones into my phone or similar weak sources like the front side of my PC or a Behringer UM2 that fares the treble less aggressively compared to driving the KS2’s off my FiiO X5 or Objective O2.

Comfort, Build, Smell and ASMR (10/10)

Though the design of the KS2 is generic, I believe it’s a tried and true design that many will enjoy as the shape will fit many users. It’s also very light. I had no problem with wearing these for 10 hours at work today. I'm still sitting at my desk using these for ASMR.

The black glossy paint is mesmerizing, the white logo is a nice touch, the plug is L shaped and perfect in my pocket.

The cable is brown and braided which puts $500 earphones to shame, looking at you Audeze! But it smells of incense and smells like my grandma’s house back in 2004. Quite the nostalgia trip.

Should You Buy?

You don’t buy the KB Ear KS2 for a do-all IEM, you buy it for the ability for it to surpass $500 IEM’s when it comes to making Lo-Fi an enjoyable experience. For $35 it’s a must buy, however even better if you can find it on sale.

Unfiltered First Impression:

The KZ ZS6, $40 Quad Driver Balanced Armature IEM's, impressive in build and encapsulated in a simple but minimalist presentation upon unboxing. The second thing I noticed upon insertion is micro-detailing, I’d say this is the best IEM I’ve heard that creates a coherent presentation while putting details as the top priority, and thanks to the quad drivers, instruments separate themselves to boost an already revealing sound signature. True, I’ve never heard quad driver IEM’s before, as they often come in custom shells, and I’ve never really felt the motivation to go for ear impressions; but for $50, I’m genuinely impressed this has surpassed other earphones like my ER4S (single BA) and iSine 20’s (planar magnetic) to reveal this much in music.

Music and Sound Impressions

I would recommend these IEM’s for contemporary music, jazz, soundtracks, refined pop music (Bee Gees for example), classic rock and whatever music you believe has a refined treble mastering. Because believe me, these are not even close to forgiving. If you’re curious as to why I left out classical music, it’s because there’s quite a dip in the lower treble area that’s hard to notice until violins start playing along. In which violins sound congested and listening immersion is broken off at this point. That’s not to say these IEM’s are congested though, these sound very open. The soundstage is very wide with good imaging, vocals extend, bass can extend deep and has a bit of punch, and the treble of course is quite prominent but only sibilant with aggressive tracks. Another thing I’d like to add about the sound is that the ZS6 are flexible with equalization in which they respond well to mid and treble adjustments. Although with the bass... in hopes of adding a little more weight in the sub-bass department strictly to compensate for outside noise, I ended up with distortion, essentially mimicking fart cannons. During quiet listening sessions, I’ve had absolutely no problems with bass quantity. Or quality for that matter.

Efficiency and Amplification

On the flip side, the KZ ZS6 are very efficient and powering them through an amplifier pretty much destroys music with more treble. Ironically I plugged these into my Oneplus 5 after and I would turn my amp's volume knob left and right wondering why the volume wasn't changing. Suffice to say, these sound absolutely amazing powered by a phone and I’m confident enough to say the KZ’s can put my amplifier out of commission with no hesitation. I believe I should thank the 15 ohm efficiency for achieving this feat, and I’m surprised the ZS6 has an extremely low noise floor paired with this efficiency.

Design and Comfort

Design is above average for the cost, I’m grateful that KZ didn’t miss the minor details. Such as an L-shape jack for portability, a sleek design (that looks familiar elsewhere), and memory wire for over-ear. However I seem to have a tad of an issue with the memory wire, it sticks out from the housing quite a bit and isn’t flexible so it’s hard to get a wrap around my ear properly. However if you’re someone with relatively large ears and can wear ear hooks similar to the Monoprice M300 or iSine 10/20, these ear hooks will do just fine.

Thanks for Reading~

The manual says the KZ will benefit from burn-in, and I’m on the fence when stating my opinion to the public when it comes to this. But after my trip with burn-in last year with the Beyerdynamic Custom One Pros, I think I’ll give KZ the benefit of the doubt this time. A 4/5 with my ears at this cost, well done KZ.

The Lear BTC-01 is better than the FiiO X5 Classic in regards to sound. If sound is all you care about then stop there and buy one already.

However I rated the BTC-01 three and a half stars and you should continue reading on why.

Like all products, they come with flaws and the BTC-01 is no exception to that. The bluetooth adapter in my opinion requires at least Bluetooth 5.0, as 4.2 is too weak to keep a clean connection to pass through a winter parka, a hand over a phone antenna and disturbing radio frequencies between the device and the BTC-01.

The noise floor is also relatively high to be used in quiet listening environments, it's very audible especially with music that has quiet moments. This noise floor can be easily ignored in public transportation or on-the-go.

3 hours is also not a long listening session, it's the equivalent of commuting to the workplace and back. Good luck if you forget to turn off the bluetooth adapter as you will probably not have enough power to listen to music on the way home.

I also have a 10000mah portable battery that turns off as a safety feature, and I assume the BTC-01 doesn't accept enough amperage because the battery pack refuses to stay on to charge my bluetooth adapter. Leaving me with the limited option of charging my device at home or through a computer.

Keeping the stock cable is also not a very good solution to the short battery life, as the connection is really stiff on initial insertion for the BTC-01, and after about fifty or more reinsertions; I've noticed a drastic reduction in the stock cable maintaining a decent grip on the IEM.

The cable itself is relatively stiff for the first two weeks, and it's hard to maintain wearing it over-ear so I used the over-ear hook from the IE80's stock cable. The cable softened over time but I found myself twisting the cable inward so the cable would hug my chin; ensuring the cable doesn't fly over my ear.

Fortunately the BTC-01 has very good redeeming features. First off is the sound. Soundstage is slightly more layered than the FiiO X5, and less claustrophobic at that. Second, mids are smooth and vocals are a lot less shouty than the FiiO X5. Treble leaves a lot to be desired, though grainy, it rolls off to prevent any harshness.

Connecting my phone to the BTC-01 is also very easy, and I've had little issues in regards to creating new connections on other devices.

The buttons are solid, and the housing has a very odd but strange rubber coating that's addicting to rub.

Regardless, I hope Lear makes a BTC-02 that addresses the issues of the BTC-01. Now would be a great time to release a new one considering the bluetooth earphones being released for phones with no 3.5mm stereo inputs.

I’ve never been a person who enjoys sound straight out of the box, I tweak everything for my personal enjoyment. Opamps, cables, foam linings, cables, equalization; everything that can get me sweet mids, bass that punches and digs deep, smooth treble that sparkles at the end, and ties together in one nice pleasant presentation.

So how far would one go for tonality, for that extra ten percent of micro-detail, for slightly more controlled peeks, treble sparkle and linear bass response? How about as far as buying an Opamp? I was completely oblivious Burson Audio created an affordable opamp that could replace many of the existing budget opamps as a premium upgrade alternative, and a representative offered me one to try out.




Had I known of this opamp prior to purchasing the NJR Muses02, or the TI LME49720HA, I would have purchased this opamp with no hesitation, as it is a clear upgrade over the NJM2068D on the gain stage of the JDS Labs Objective O2 amplifier.

So what’s wrong with the NJM 2068D?

The 2068D does nothing wrong, but the Objective 02 sounds fatiguing with this opamp. The upper mids are glared, there’s not much weight in the low end and treble is grating. But it’s less than one dollar on the market and easy to replace.

The LME 49720HA is highly regarded, costs a third of the NJR Muses02 why not use this opamp?

The mids are a touch warmer but also clearer than the 2068D for the cost of the upper mids being too bright and shouty even with the Sennheiser HD600. The treble is slightly rolled off, sub-bass still to be desired; maybe the Muses02 will fix the low end.

And you know what, the Muses02 does fix the low end.

The NJR Muses02 is bass reincarnate! Sub-bass digs deep, bass tones in piano and cellos resonate and pronounce themselves in thunderous body, vocals linger and wrap itself in warmth, treble is there but isn’t refined like Burson Audio’s opamp. Slow decay and a darker presentation is why you get the Muses02. The problem with the Muses02 is that bassy ear/headphones can sound bloated, and peeky vocals tend to stay around a little too long due to the slower decay. As of December 19, 2017, the Muses02 is also ten U.S. dollars more expensive than the Burson Audio opamp.

Okay so how do I make the voices go away?




Introducing the Burson Audio Supreme Sound V5i Opamp. Percussions hit hard with speed and definition, treble sparkles, micro-detail in the background is brought forward, and peaks are more controlled than before. The dreaded honk of the Audeze iSine 20 is reduced, the Sennheiser IE80’s bass hump is controlled, the Sennheiser HD600’s treble is brighter. The V5i isn’t a magic cube that does your taxes and makes your problems go away, but the V5i keeps sound under control. A definite upgrade over the stock opamp in my JDS Labs Objective O2, and it will stay in my amp forever.

So if you want to keep your current gear and want the extra ten percent of micro-detail, for slightly more control in peeks, treble sparkle, linear bass response and natural tonality; then I highly recommend the Burson Audio V5i Opamp.

Why 1 Star?

• Right driver died in 6 months, but a certified Audeze repair center replaced these instantly for me.

Why 2 Stars?

1. Toss a tin can (that has both sides cut out) to your favorite vocalist and ask them to sing through that, that's the iSine 20 mids. Less treble and bass presence on the iSine's only emphasize this. I'm disappointed by first impressions. Android and PC users only wish they had a device that had a lightning connector for a Cipher Cable, because yes, the Cipher cable has a DAC with DSP filters that change how the iSine 20's sound.
2. The smaller earhooks are not rubber coated therefore feel and look like dollar store quality plastic you find in sunglasses. The earhooks are not malleable like Sennheiser IE80's memory wire earhooks, thus the iSine 20 earhooks apply a small area of pressure behind the back of my ear since they stick out.
3. The carry pouch has 4 holes on each corner, the size of dime. This wouldn't be very protective if a water bottle leaks in my bag and the iSines are under minimal protection here.
4. Earlocks only come in 2 sizes, small and large. Medium would be nice. Even Bose IE2's provide 3 StayHear tips. Taking these for a walk is a chore, I don't even want to take these on a run.
5. A straight plug cable in a portable earphone, don't expect to have a flagship phone and expect to bend over with a straight plug. I definitely can, but I get a nervous feeling that one day that I'll end up with a flayed cable.

The combination of all the negative aspects of the iSine is enough to justify the 2 star rating for a $600 earphone.

What Makes the iSine 20, 3 Stars?

1. The iSine 20 has very low distortion, thus allowing flexible EQ settings. The iSine can be bass monsters, mid masters, or both at the same time. The instrument separation is amazing after smoothing out the frequency response (even better than Etymotic Research ER4S or the Sennheiser HD600). Scroll to the bottom to see EQ settings on Equalizer APO.
2. Semi-open; these have stayed in my ears for 6 hours at some point at my desk. I only had to adjust them every hour. Closed back earphones/headphones are fatiguing in comparison.
3. Desktop headphone performance in an earphone. Imaging is great, soundstage is great, even slightly better than my Sennheiser HD600 for gaming.
4. The carry case will smell like fresh electronics for a very, very long time. I like the smell.
5. To me, these are aesthetically pleasing and head turns in public transit prove my point. I've only used them in a subway for one day, the lack of isolation from screeching train tracks is disappointing.

What Makes the iSine 20, 4 Stars?

1. It's a planar, an in-ear planar.

Should you buy these?

Sure, if you like fiddling with EQ or seek a desktop solution and dislike headphones. Otherwise... no. Monoprice Monolith M300's probably have a better sound signature. The other option is wait for the second revision of the iSine 20's if there will be one. This one isn't worth full price.

Equalizer APO Settings:

Spoiler: Equalizer APO Settings

Revision 43 (Last Edited: May 22, 2019)

Filter: ON HSC 5 dB Fc 30 Hz Gain -7 dB
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Spoiler: Equalizer APO Settings

Revision 44 (Last Edited: June 1, 2019)
Filter: ON HSC 12 dB Fc 30 Hz Gain -5 dB
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So I finally have my hands on a headphone I never thought I would lay hands on. The Sennheiser HD600. Despite the high amount of positive reviews these get, I disregarded THEM in the past and explored other choices on the market. Even the Veilheiser HD598 that I bought were a slight disappointment. Mids sound too laid back and hidden behind a silk curtain, Japanese female vocals are slightly sibilant friendly from the sparkly treble, the soundstage isn't intimate enough and the bass seeped into the mids without much sub bass extension. But I like the mid bass presence, it is wide and gives any instrument; especially cellos, a meaty and down to earth presentation which was quite opposite of the Q701. Was it not for the Q701, I'd give the HD598 more praise. I know the HD598's are in a different price bracket now (150CAD) but at the time they were a bit more (200CAD) and costed the same as a Q701.
 
The Q701’s. Their Mids are sweet, clear, crisp and definitely haunted by the 2khz peak that introduced artificial tones. The peak is a double edged sword that could also give some fortissimo-like emotion to poprock music, boost metallic textures from string instruments and it's the reason for the sweetness in the mids. The treble has texture and it's easy to tell whether the drummer is using a brush stick, wood stick, crash, splash or riding. But treble lacks sparkle of the HD598. Bass extended deep, and the clean mid bass gave room to vocals that sounds much leaner compared to the HD600. But as much detail the Q701’s have, they're a specialized headphone, Japanese media shamelessly advertise the headphones and there's no doubt their music strives with the Q701. Although the flip side is fatiguing, dry, fast decay and indeed artificial with the wrong recording. No doubt a favorable characteristic for medieval renaissance or drum and bass.
 
The HD600 I believe has so many strengths that it took me 30 minutes  to shelve my Q701’s. There were so many mentions of the HD600’s guilty of the infamous veil, I didn't want the weird mids of the HD598 to touch my beloved vocals. There was so much flak that the entire HD600’s simple truth was the treble recession compared to other headphones. Other than that, all instruments and vocals have such a natural decay, they're smoother and female vocals simply extended into the 1khz area that was overshadowed by the 2khz peak of the Q701. Mid bass isn't just bloomy like the Hd598, but it's thick, detailed and actually so great it's able to cover up the sub bass roll off that I could easily disregard. The HD600 has a hidden sparkle and the treble itself is significant enough to balance out the warmth and not show any sort of sibilance.
 
Ideally I wouldn't be able to recommend the HD600 for competitive gaming because of its lack of forward and rear soundstage. I'd say I recommend it now because valve has created the HRTF headphones setting for counterstrike global offensive. All it does is muffle rear sounds and create a wider soundstage that is not usable with the Q701 because of its already large soundstage. But the HD600’s soundstage and imaging is cohesive compared to a Q701. Some people say the hd600 has a small soundstage, I disagree. I've heard the hd800 before and I can simply say that kind of soundstage is enjoyable, but way too big. Others of course may disagree.
 
One of the absolute amazing feature of the HD600 is that it is modular. I can replace the headband, headband foam,ear cups, the shell, the cable, the driver, the inner foam of the ear cups that I replaced with pantyhose to give the headphone a luxuriously spacious feeling. All without using tools. It feels so much lighter than the Q701 too. But I wish my headphones were new, because I would have liked the stronger clamp. The other name for these are the snapheiser, and for that I won't risk trying to bend these back.
 
The HD600 is not dark and not too warm. Trust me, take it from a bright headphone user who is satisfied with a JDS Labs ODAC/O2 pairing of an ER4S or Q701. I can also gladly run them off my Sony C4 phone and it will not disappoint. However the HD600’s are definitely capable of equipment scaling.
 
My headphone search has ended, so you could possibly end yours with an HD600.

 
     My past headphone experiences with Audio Technica have been a good one. The ATH-A900X being my first 'audiophile' headphone. I loved its thick sweet mids for vocals, sharp treble and slightly big boomy bass that surely impressed me that was still new to audio. I still use it today as a closed back solution. Then came the sweet looking ATH-EW9, and finally the CKM500 for which my dad swapped me for an ATH-CHX7.
 
     I judged the ATH-CHX7 by its’ cover: “with a big housing like that, surely there has to be a big soundstage behind it, and with earbuds similar to the Bose IE2’s; this has to be an IEM made for home usage.”

     And I was right. The CHX7 has a good fit that it never loses its’ optimal position for sound direction no matter what facial expression I make. Unfortunately the Bose IE2 has the CHX7 beat in regards to the initial seating. Except I have a problem with earbuds that rely on the tragus and antitragus for seating earbuds: they hurt. Earbuds that use foam as a cushion are much better at this and don’t make my ears sore like the Baldoor E100 or VE Monk. I’m not a finicky person when it comes to comfort, I love my ER4S, Grados, AKG Q701’s that are infamous for their comfort issues. But the Bose IE2 and CHX7 that relies on expanding the (anti)tragus for fit does cause discomfort after 30 minutes to an hour even with the smallest tips. The CHX7 beats the Bose IE2’s, E100’s and VE Monks in staying in its’ position
 
     The isolation is little to none but leaks little, I can’t recommend to use these at a library if you want to avoid annoying anyone else. They leak less than the Bose IE2’s, even more less than the Apple Earpods. If you wanted isolation, I would suggest smaller drivers (typically balanced armature) that focus on seal.
 
     Though the soundstage is a bit bigger than average for an earbud, I’d have to say cheaper earbuds like the VE Monk and Baldoor E100’s beat the ATH-CHX7 in terms of airiness. Both solutions are much cheaper solutions than the CHX7.
 
     The bass carries itself from the Audio Technica A900X.  It’s a bit boomy and warm, but the CHX7 doesn't have as much extension and rumble. Thankfully, the bass body is not intrusive towards the mids.
 
     The mids here are fairly disappointing, especially upper mids for an Audio Technica product. There’s a dip in the 1-2khz area and the graphs show it. During fortissimo portions of a lyric, it feels as if the vocalists move further away from the mic the higher octave they go. I listen to anisong, japanese pop/vocal pop/pop rock so I’d say I’m a bit sad about this. Rap seems to do fine though! Male vocals are untouched.
 
     I spend a lot of time in the studio, concerts, bars when I get the chance. So what I found in headphones is that there are a few instruments that are very hard to reproduce in the lower price range. Pianos for instance require a nice smooth bass body to an upfront midrange, Sennheiser headphones do this very well.
 
      Except for the sake of reviewing, I will specifically explain the Tom Toms in a drum set. Tom toms require good technical features of a driver to be fast and a flat response in the midrange to treble transition for them to sound good. The CHX7 artificially boosts the tom toms but the drivers lack speed to reproduce the nice smack and cleanliness. I would also like to mention the CHX7 make tom toms sound thick, which doesn’t sound right. This thickness also makes female vocals with lower octaves sound like if they’re singing with cupped hands. I’d rather choose the E100’s that simply smooth out this part of the midrange and try and hide the imperfections of the earbud. It’s not that it’s a bad method, but it really works! This artificial boost also makes synthesizers fairly fatiguing that mixes into the treble.

     So this is where the dreadful lower treble of the CKM500 comes in, the CHX7 has a less grainy version of it. I believe the CHX7 has sparkle, for some songs it’s noticeable but the lower treble washes it out. Here’s an example of the treble:
 
 
     When a label on the box says “Made for iPhone/Smartphone/Android”. It’s not just a marketing technique, but the engineers know what they’re doing. V-Moda also has this label on some of their boxes. Typically it’s saying that the product was made for sources with low impedance outputs. The CHX7 sounded too sharp, fatiguing and had leaner bass from a Fiio X3/X5. The ODAC/O2 boosted the already boosted bass and lower treble, at the same time refining instrument separation. And my Asus Zenfone 2? It sounded pretty darn good compared to the other options. The lower treble wasn’t offensive, tom toms sound snappy but it’s not piercing unlike with more powerful sources. Youtube videos didn’t sound too bad either, the CHX7 matches well with softer recordings.
 
     I’ve always believed Audio Technica does amazing headphones, look at the highly regarded WS99 and their air series. Audio Technica just fails to impress me with IEM’s. With a $20 bill, you can look at better earbuds like the already mentioned Baldoor E100’s (that comes with a good inline mic) and VE Monk if you don’t mind waiting a shipment from China.
 
 
 
     My bias? Headphones as close to neutral in regards to sounding like 18 feet by 27 feet rehearsal studios. If not then nice clean midrange with upper midrange emphasis for japanese vocals, good treble response and tight punchy bass that I don't mind being on the leaner side for less fatigue.

Like all my reviews, I begin with sound and then more into personal experiences. I only write reviews when I'm totally satisfied with a product (2+ years of ownership) or if I've had my final moments with them.
 

 The sound of the Shozy Alien is very delicate and organic and has a soundstage similar to the JDS Labs ODAC/O2. Except the treble is smooth, mids are sweeter and overall clarity sounded better than the ODAC/O2. Each instrument had its' own weight and though the soundstage wasn't very expansive, the imaging on the Shozy Alien is definitely an improvement over all of my sources. It was honestly hard to convince myself that this DAP sounded better than my entire desktop setup.

The UI wasn't complicated as I thought it would be, the only gripes is that the buttons were a bit too easy to press in my pocket. If I sat down with the Alien in my jean pant front pocket, there's a chance that a button would be depressed and pause my song.

Unfortunately that's all I really have to say about the Shozy. Let me begin by saying that despite the 2 stars, the Shozy is an amazing DAP. I thoroughly enjoyed it for the 4 hours of the pre-charged battery that it provided me. I wanted to praise this device as much as I wanted to, but instead the Shozy left a bad taste in my wallet.

The first issue that came up is that it didn't recognize my 8gb micro sd card that all my other devices were able to use. I tried formatting, but then after every first 5 songs a loud buzzing noise would come up and the device would freeze. I tried changing the song order but that didn't work either.
Next I tried charging the Shozy through my USB 3.0 ports. Next thing I know there's a Windows error pop up saying that the USB port had a short circuit; that USB port is actually now fried.
Turns out that something in the Shozy came loose and I was suggested to try re-soldering the Micro-USB port in the device. I used a T1 Pentalobe screwdriver under a microscope to unscrew the Shozy... All the screws are stripped and I'm now left with a dead alien.

I will edit this review when I get the funds to replace the Shozy Alien, because I'm still in love with the sound this thing provided while it lasted.

TL;DR Review of the AKG Q701’s

Accentuated Mids: Enhances most female vocals, also forwards vocals, “livens” synthesizers in electronic music. Can cause vocals to sound uneven due to the 2khz bump.
Grainy/Textured Treble: Gives texture and dynamics to ride cymbals and high hats, may force treble into songs that suffer with treble. i.e. Metal genres. Not to be confused with “sparkly treble”.
Lean/Solid Bass: Bass is solid and fast, impact hits hard but rumble is lean, benefits in most techno, jazz, and classical/orchestra music. Quality of bass leaves the listener wanting more.
Soundstage: Large soundstage that has a 3D Surround better than 5.1 gaming headsets. Suffers from center imaging that relates to “in-your-head” feeling, however it has a prominent forward stage. Soundstage similar to standing in the back 24’x18’ room, 5' away from the wall.
Comfort: Bumps in the headphone gets uncomfortable overtime, earcup placement is crucial in relative to sound perceived. I.e. earcups placed too far backward can cause mids to sound muffled. Velour earpads and ~270 gram weight allows comfort over long periods of time.
Build Quality: Dropped over 5 times at height of 5’ (unintentional), still working. Plastic used for earcups allow scratches to not be visible. After 3-4 years of constant usage, earcup swivel may develop friction and creak.
“Sound Signature”: Somewhat reliant on the source, however most of the time the Q701's sounds dry due to the fast decay of notes. Especially sounds analytic when compared with other headphones, soundstage gives a dynamic feel to songs, but it suffers from center imaging in regards to intimacy.
Amplification: Requires more current than voltage to power them right in my opinion. Performance on Q701’s rely more on the quality of source rather than how much power it can output.

Conclusion: The AKG Q701’s are bright sounding headphones at first without proper amplification and brain burn in.
If you don’t need isolation for gaming, throw away your gaming headsets and get AKG Q701’s. If you’re looking to get serious with your music, like detail retrieval and don’t mind spending an amplifier/dac combo that costs the same as the AKG Q701’s; get yourself a pair. If you want boomy bass, if you want isolation, if you want a smooth experience; look somewhere else, the AKG Q701’s aren’t for you. The Q701’s can be found for cheap now and definitely worth it.
 

Day in the Life with AKG Q701’s

 

Introduction

I got to visit a studio today and it was nothing short of audiophoolishness delight. Upon entering the studio I was greeted with just two tower speakers made by Strauss (Strauss-SE-MF-2). These gave off a very life-like impression in sound and I was quite blown away by how close they sounded to actual instruments.  The only issue I have with the speakers is that I had to be at a certain position in the room for everything to sound just right in regards to soundstage and for the treble to not sound muffled. I guess you could say this is similar to how the Q701’s need to be centered for them to sound right.

Alongside listening to the studio, I got to listen to my friends’ band play in a rehearsal room a while ago, a concert hall, and a venue all with the same song. Though none of you know the song, I used this song as a benchmark for all my tests with the Q701’s.
Cataclysm by Motivated by Foolishness
http://www.youtube.com/watch?v=lJ6NWu8lZ8w
Songs found above.
http://motivatedbyfoolishness.bandcamp.com/releases
 
The Q701’s I have are third hand, pre-burnt in, Austrian made, and so far have about 3000 hours on their mileage, not including the hours used by the previous owners. My review is solely opinion based and I’m not too hard focused on specifications (except for the measurements), and please do take the titles of the review into consideration. As there may be misconceptions of my review if they are ignored. I will assume you already have done research about the Q701’s from other reviews, I’m just providing more insight.
 

Q701's vs Real Life Instruments

 
After an entire day of listening to just instruments. I came to the conclusion that the Q701's:

• Sound a bit dry, instruments seem to not linger around very much (not regarding reverb though)
• Lack a bit of center imaging
• Tom toms don't have enough attack
• Treble is a bit grainy, and needs some more sparkle. However the Q701's have the high hat texture not many headphones have.
• There needs to be a bit more upper mids/lower treble flatness, electric guitars though have the detail and crescendo-like sound, they don't have the smoothness needed during reproduction. This upper mid is what makes pianos and violins sound more solid, the Q701's lack the solidity of piano notes.

 
Needless to say I believe headphones exaggerate sound overall, the only way that reproduction can be saved here are through binaural recordings. In which replicate sound much better in comparison to regular stereo recordings. Unfortunately, most songs that I know of aren’t tuned and mastered for headphones, rather for speakers instead. If I had to mention soundstage, I’d have to say the Q701’s are spot on for an acoustically tuned 24 feet by 18 feet room with musicians playing in it. Nevertheless, soundstage does indeed require a good sound signature to illustrate the distance of instruments. So the only nitpicks or comments I have about that is the flaws I mentioned at the beginning of this paragraph in regards to soundstage.
 

Q701’s vs Strauss-SE-MF-2 Studio Monitors
 

The problem I actually have with listening to reference tuned studio monitors is that they sound a bit bland with my songs. Mids don't stand out enough and bass is a bit too much for my taste.…
 
The Q701’s lean bass allows more detail for the rest of the spectrum, from strings getting plucked to the fingers sliding along the neck of a guitar. As you’ve noticed, I do indeed enjoy a certain part of headphones even BETTER than live performances or studio monitors; and that’s a sense of intimacy. Though these headphones don’t have the accurate reproduction of studio monitors, or the ‘in-your-head’ feeling with other headphones, I can get quite enough of intimacy through the Q701’s. I believe that intimacy can be achieved through:

A) As if you were in the room with the band members
B) Having the band members being shoved into your brain.
So it’s fairly obvious which one the Q701’s strive for. (B)
 
 

Q701's vs Other Headphones in Brief.

 
So why do I still have the Q701's?
Why don't I have DT990's? In which they clearly have more bass oomph and a higher treble spike?
Why don't I have HE-400's? That have a flatter sound signature, extremely solid sub bass, and smoother treble that allows me to turn up music higher?
Why don't I have HD800's?
 

Sennheiser HD800

Well first off, I don’t have the funds for HD800's, if I had the money I'd sell my Q's and own the HD800's. I've auditioned them before and fell in love with them.
 

Hifiman HE400

 
HE-400's yes, are nice, but I prefer the near weightlessness of Q701's. The issue I had in regards to comfort with the AKG Q701’s are indeed the headphone placement and headband. They have to be placed somewhere near center of my head so that sound is directed into my ears and that I get full advantage of the spectrum. As for the headband, I cut off the bumps and replaced it with 0.3mm of foam. The bumps molded into my scalp and eventually I got fairly uncomfortable when I had less hair on my head after a haircut.

Also,  the HE 400 don't offer a big enough soundstage for me. If you’ve heard of ASMR, the enormous soundstage heightens the effectiveness of ASMR videos. Also due to the enormous soundstage of the Q701’s, instruments feel as if they’re just being suspended mid-air, ready to be picked and listened to individually.

Beyerdynamic DT990 250 ohm

DT990’s (250ohm) slightly emphasize bass and higher treble spike, although I didn’t feel the same excitement of music when the mids weren’t quite there. However the DT990’s actually have a bit more detail.

Other Headphone Recommendation that Compliment the Q701

 

Audio Technica ATH-A900X

 
My favourite “fun” headphone would be the A900X. When I switch back to the Q701 after 3 hours with the A900X, the Q701’s sound life-less and I need at least 15 minutes for my ears to burn back to the Q701’s. In which I listen to Flamenco Rumba or a song that takes advantage of soundstage to get myself accustomed to again.
 

Etymotic Research ER4S (Tri-Flange IEM)

If you have the Q701’s, I recommend the ER4S. They have similar sound signatures and the extreme isolation of the ER4S compliments the Q701’s open back nature. Of course both headphones have comfort issues, but if you already have the ER4S or Q701’s, we can already assume you’re a masochist.
 

Sennheiser HD598

 

Powering the Q701’s

 
I’m just going to flat out say, there’s a certain point in which the Q701’s don’t need any more amping. I believe, similar to the music played through these headphones, the Q701’s are picky with its sources and need a good match for them to sound good and taken to full advantage. Heck, if my initial purchase of a mid-fi headphone was an HD650 instead of the Q701’s, I’d probably have about 500 songs in my entire music collection, rather than a tailored 180 songs for the Q701. Although I have no regret, I’m enjoying my 180 songs 6 hours a day, for the past 2 years. Like any headphone, each one has their own pair of songs that just simply sing. I can't emphasize how nice Jazz sounds with the Q701's.
 

FiiO E07K

 
The nature of FiiO products so far is that their soundstage is a bit narrow compared to desktop DAC’s like the JDSLabs ODAC.
The FiiO X3 sounds a bit better than the E07K in terms of clarity and bass solidity (Firmware 3.2).
 

FiiO E12

 
The FiiO E12 cleans up the sound of the X3 or E07K. It smoothens the treble, enriches the mids and the bass is a bit more solid.
 

Odd Devices

Regular devices such as an iPad, Supreme FX III (Asus Crosshair Formula-Z Motherboard/Onboard), Xonar DGX and Sony Walkman E474 (which the Sony could BARELY drive the Q701’s to audible levels) make the Q701’s sound “average”. I would have sold the Q701’s and stuck to my A900X if it weren’t for source upgrade.
 

JDS Labs ODac+O2

The jump from the E07K to the ODAC/O2 by JDS Labs however was the game changer, and which I started loving the Q701’s. Warmth covered the harsh treble of the Q701’s, and bass was there! Mids sounded more intimate, and treble had more texture to it.  Bass wasn’t emphasized too much but it hit hard and it was THERE!
 

Dared MP5 Vintage Tube Amplifier

Now I’m powering the Q701’s with a vintage tube amplifier, the Dared MP5. To be honest the sound didn’t improve very much, if anything it was a change in sound signature. I believe all that changed was that treble is a tad bit more revealing, and a slight hint of natural distortion in the treble peaks exist so that treble is more forgiving. Mids are sweeter, the bass became increased a bit in quantity for enjoyment purposes. The Dared MP5 has some background noise/hiss, but for some reason, these don’t pick up the noise as much as my other headphones even though the Q’s are detail monsters… This is quite a contradictive sentence, but if you have a noisy amp, you’d be glad to pick up the Q’s.
 

Side Notes
 

This could simply be an exaggeration, but if I listened to a headphone long enough, my brain starts burning in to that sound signature. Then once after listening to a new source after a period of time, the difference is evident. The opinions of this new change of source is also biased with emotional opinions. These emotional opinions sometimes get mixed in with facts. When I switched between devices too quickly, my brain doesn’t have enough time to adjust to the new source. So as a result I believe that what I’m hearing with the improved source sounds the same to downgraded source. That’s how minor the improvements are with the Q701’s. However this proves that the Q701’s are sensitive to change in sources.

Gaming with the Q701’s

 
After the upgrade to the ODAC/O2, soundstage felt 3-Dimensional and I could hear the distance of bullets whizzing by in Battlefield 3. If a bullet whizzed across my face 2 meters in front of me, I can tell, if bullets hit behind my feet, I can tell. Out of all the $300+ gaming headphones I’ve tried (Astro A40’s, Razer Tiamat/Kraken/Blackshark/Carcharias)… there’s nothing more immersive than a product just meant for audio like the AKG Q701’s. Headsets are just utility knives, packing devices like a microphone, batteries; they're basically a jack of all trades and a master of none.

In regards to games made by Valve, you’re in for a treat. Games like Counterstrike Global Offensive, Team Fortress 2, Half-Life series all benefit from the AKG’s. Valve already implemented an “around your head” soundstage that’s immersive for regular headphones/headsets. The additional soundstage from the Q701’s are beneficial for sound depth. The only issue with Valve’s audio is that they didn’t implement a very good algorithm for sounds in front and sounds behind. In which the Q701’s falter because it doesn’t have a solid central soundstage. Other headphones I have such as the A900X do better with Valve’s front and rear soundstage due to the angled drivers.
 

Q701’s Modded vs Unmodded

 
This mod is known as the AKG Sticker Mod. The sticker mod is literally a sticker inside the earcups that can be removed to increase sub-bass. All you need is tweezers to stick into the "Q" grill of the earcups, rotate it counter clockwise, unscrew two screws to carefully remove the plate that requires some force to peel off, and finally use the same tweezers to gently peel off the sticker that covers the bass port.

When I did the frequency response sweeps on the Q701’s, it was fairly evident the sub bass came first a lot earlier than the earcup that had the sticker still on. There’s definitely a tad looser bass with the sticker off however, although what you get is sub-bass, and a bit more bass to boot. The downside of the sticker off is less mids, and less airiness in soundstage due to the increase in bass.
The good part of the mod is that everything sounds neutral one might even consider it as an improvement, not an improvement for me; but a possible improvement nevertheless.
Mids are flat, bass is more full bodied, treble is not as grainy and has sparkle to it. Similar to the Etymotic Research Er4s frequency response, except the ER4S sounds more lively with this response than the modded Q701's.

Note: This is a raw measurement of the AKG Q701, usually there would be a compensation chart to simulate sound perceived in the room, but I don't have that unfortunately. That's why the treble seems over-emphasized here.



The stickers off also increase the higher treble area. I don’t notice this at all since the bass balances this out. Also, the graph looks weird, I apologize if this isn't an exact interpretation of the AKG Q701's, because the mids and bass through my ears sound like they're balanced with the treble.

I tried the bass mod but the slight reduction in soundstage (in regards to circumference, not depth) somewhat turned me around back to stock.
I prefer my stickers on, I’m a purist and prefer to use the product as is.
 

Alpha Design Labs iHP-35 Cable
 

The cables indeed do sound similar. The signature of the Q701's are still there; but it just sounds a bit smoother now like my Sennheiser HD598's treble.
I had a hard time justifying a very expensive 1.5m cable. The guy at HeadfoneShop kept telling me for an entire year, "Hey, it's up to you if you want to buy it man, you just have to believe me there's a difference". As he continued to play World of Warcraft on his laptop.

I took up his offer a year later and finally bought it.
Was there a difference? Thankfully yes, I was ready to return these. All my doubts lead to no until I finally got a chance to listen to the overpriced cable.

The cables made my Q701's lean a bit towards the smoother side.
There's a bit more treble grainyness on the green stock cables compared to the ADL cable that sound oh so great with guitars that I miss.
The cables are less sensitive to my amp's hiss but more sensitive to detail somehow.
I would also like to re-iterate that these cables introduce a bit more sibilance.

 

Your Mileage May Vary (YMMV)

 
My audio preferences? Big soundstage, solid bass, forwarded and sweet mids, and treble that could attack fast in electronic music and provide texture for high hats in which the Q701’s definitely provide. The Q701's are not headphones for everyone, since these headphones are only $150-$220 on the market, we can assume that one hasn't gone into the higher end market that already has a headphone tailored for their music preferences. Or an even better headphone that presents music better for a wider range of genres. A place that is not in reach for the near future.

The Q701’s are indeed a hit or miss, and for me they were definitely a pinpoint shot. I believe that one needs brain burn-in equally to driver burn in of the Q701’s for these to be enjoyed. I certainly don’t think these are headphones meant to be enjoyed out of the box.

Thanks to BlueMonkeyFlyer for the In-Ear Microphone!

Unboxing

Upon unboxing, I knew what the Sony MDR-1R MK2's were intended for; luxury. It came with a box very similar to the Sennheiser HD800's packaging, very pleasing to open and everything felt of quality to handle. In the box was a japanese instruction manual, a cordura pouch, 3m cable, 1.2m cable, and finally, the headphones. Oh and the japanese company I bought it from included a cute paper hand fan

Design and Comfort

The headphones in my hands feel very light, with smooth swivel cups, and a somewhat solid plastic build.
On my head, the clamp is fairly light, accompanied with a soft pleather headband, and pillow-like earpads.
The aesthetics of these are just amazing, a very modern look with a simplistic design, glossed paint in the right areas, aluminum matte painted earcups and solid plastic frame.

Unfortunately what these do exhibit is the common jack rattle found in the first MDR-1R headphones, a common fix for this is to slide a piece of paper on the sides of the jack that rattle against the tube holding this. For my fix, I took modelling clay, wrapped it around the base of the plug, and pushed the cable into a jack; forming a seal.
Although the cable also exhibits its' own type of rattle. The strain relief is not a snug fit on the cable, and if the cable hangs straight down; rattling will occur. A fix for this would also be sliding something thin under. These flaws are a factor of why they may not be a suitable portable headphone if the issues are not addressed.
Like most cables under cold weather, these will tense up and may rethink your decision on having these has earmuffs.


Sound
 
Although looks do play a part as a portable headphone, the sound accompanies it well.
I've given these headphones over 100 hours of playback, so they should be well burned into my brain and driver wise.
Sadly to say, I do not have the original 1R's and won't be able to compare the updated version to them.
 
The sound signature of these are warm and relaxing, due to this, poorly recorded tracks or lower bitrate files are forgiving. Although, these cans are midrange centric that benefits piano based recordings and some female vocals. The lower treble faces a dip, and for the better. My japanese poprock recordings are quite enjoyable and quite forgiving to the typical sibilance. I think the higher treble is very interesting, it actually sparkles above the warm mids, which benefits the already sweet and warm sounding mids.
In my opinion though, I think the mids are too tinny with the 1-2khz presence that destroys some of my younger female vocalists due to their higher pitched voices.
I think Sony could have done better with the bass, it doesn't feel it extends, it punches a bit, but overall it's just "there". This might be due to the warmth.
In outdoor environments, the bass does get lost, and does not isolate very well. On the flip side, these don't leak too much sound at moderate volumes so it was usable in libraries.
 
The soundstage of the Mk2's are typical of small headphones, it is small, but not congested. Despite the small soundstaging and warmth, instrument separation is quite impressive on these cans.

Conclusion

Like all headphones, I need to wear them for at least 10 minutes with playback to get accustomed to the sound signature.
The 1R Mk2's are not an exception, it's quite picky on some recordings. Working best with jazz, poprock, punkrock, rock, pop, and hip hop. Genres that sound full and warm already, will feel muddy.

Would I recommend these to the regular consumer? No, because some tweaks would be needed for the jack rattle issue. However, get past this defect, and it's an interesting, and VERY comfortable portable headphone to own.
 

         As of 2013, I could only find one pair of these on the internet. It's a shame because from my experience, cheap earbuds are oriented around the muffled bass emphasis and exhausting higher mid ranges. I myself came from the Audio Technica a900x and Bose IE2's which sound darker compared to these $10 earbuds. I love rich vocals and acoustic music, so it's only natural I loved these earbuds.
       
         The E811LP sounds very transparent and clear on the mids, almost as if music is just floating to my ears rather than being pushed by large headphone drivers. Due to the open nature of these earbuds, I would even like to say they are less exhausting with female vocals better than my a900x, especially when the singer begins to shout at the top of their lungs. They sounded great with acoustic music and pop rock involving female vocals. Forget about electronic music, metal, classical, and pop; these earbuds are JUST midrange, no bass and textury highs to support those genres. Since it's just midrange, any instruments or vocals around the same frequency will become muddled in the shallow soundstage.The bass sounds like a door knock, similar to smacking a mallet on cement. The highs roll off a lot, high hats are smooth and present. Though transparent, these do leak sound at higher volumes and begin to distort starting with the midrange. We could say these are cheap open back earbuds made for quiet environments to listen in.
 
         What else do I like about these earbuds? Well, they are old! What I like about old stock earbuds that came with a cd walkman player is that they are tuned right. These aren't marketted with the newer digital walkmans that emphasizes EQ'ing. The E811LP don't extend at all from both ends, but they are smooth and roll off at just the right points to justify themselves as Acoustic Earbuds.