[Hotspringseeker]

Late to the thread here but since threads go on forever in cyberspace, I'll chime in too..

I just received a pair of Q701's today and spent many hours listening to my music an really loving the sound, while immediately realizing they lacked bass as they all say.
As a Sennheiser HD6xx fan, and a fan of 1980's Fostex T50RP planar headphones, these AKG's are surprisingly excellent sounding and these aren;t even "300 hours" break-in used.

I'm old fashioned and drive my cans with a 1980 Luxman R-1120 receiver, which has a better sound for cans than any headphone amp I;ve been able to afford.
So I don;t mind giving the bass and treble a few DB's bump or drop as needed according to source and speakers. I listen to alot of vinyl and different carts have a different sound..

I thought I was happy with the stock "Quincy Jones sound" then I did the "bass mod" and these cans opened up immediately.

There is not "too much bass" as all. If anything, i can run everything flat and they have a natural sound. Like the HD600's, but a bit better and more airy high end.

It's so easy to pop the caps and mode these I will be experimenting further with wool felt and cotton inside the cups until properly tuned.
I Love cans that can be modded and tuned.
A good example are my Fostex planars modded with felt and clay.
they totally smoke the new Audeze and Monolith planars with twice the size drivers.
I sold my Monoliths to get these Q701's knowing they could be modded.

Listening to the Vangelis Blade Runner soundtrack right now and this mod took these cans to a higher level.

I wonder why they put the tape over the hole to begin with?
Maybe they are a little "tighter" with it, an the bass is a little "sloppier" without it..
But I listen to tubes an vintage gear with a <100 damping factor so "loose" and "flabby" bass are pleasant to my ear...
And with the Bass mod, it still doesn;t break up on the bottom...

Listening to the Blade Runner soundtrack will prove this right away how good it works!!..

I'm a new fan of these AKG cans.. they are a welcome addition to the headphone stable!!

 

[mikaelmark]

Many people can´t understand why AKG (Harman) choosed to assemble those two stickers at the back of the drivers, but I´m pretty sure why; As all those headphones are intended for use in studio with mixing/recording, it´s preferable to have the detailed sound with extended treble, and they do not care if they have the harsh/cold sound with the high treple peak around 7 kHz.

So, I just see it´s rather logic to remove those stickers, for those of us using those headphones for listening to HiFi music.

Another problem with those headphones, are the headband that´s used as conductors to the right side, as I believe it´s not made of any kind of pure copper. If it´s some iron or steal, it should be horrible for use as a conductor in HiFi!

My solution was to cut all wires soldered to the headband and then soldered a twin cable glued to the headband while using four small cable ties to holding them in position (maybe I will remove those, as the glue will however hold the cable on it´s own). Otherwise, I can not see any postive aspects if one will upgrade to a better cable! Remember; A chain is not stronger than it´s weakest link!".

An while I had the grills removed, I glued som very thin filter from a breathing breathing mask, inside the grills. This I imagine will work a bit as the HD800´s white reflectors.

Also, my K701 had the black foam in front of the drivers and I used a scissor to cut the areas in front of the reflectors surrounding the drivers.

I also washed both the cushions, foams and leather head band with soft soap and after drying, I used a leather balsam, same as used for leather sofas, car seats and leather shoes.

My earlier (now broken) K702 had the leather head band with the nuckles, and I agree it´s really giving headaches! So I´m happy those K701 are having the straight leather band without the nuckles!

Below are some pictures of the mod;

 

[MrPhilicorda]

Many people can´t understand why AKG (Harman) choosed to assemble those two stickers at the back of the drivers, but I´m pretty sure why; As all those headphones are intended for use in studio with mixing/recording, it´s preferable to have the detailed sound with extended treble, and they do not care if they have the harsh/cold sound with the high treple peak around 7 kHz.

As someone who uses the K702 in the studio for mixing I think they get way more useable after the mod. Thing is, for studio work you must hear EVERYTHING, or as close to it as possible. I can't make decisions on stuff I can't hear, I was constantly messing up the low end of the mixes because of the lack of bass on the K702. Later I switched over to the Sennheiser HD600 which have a much flatter frequency response and consequently are better for mixing. However, after the bass mod the K702 were back in business in the studio, now I can pretty much hear everything and compared to the HD600 the benefit of the AKG's is a more detailed treble and wider soundstage. So I keep switching back and forth between the two.

 

[mikaelmark]

My modded K701 have just beenburned in with white and pink noise/sine waves for two days now, at around 70 - 80 dB. Then compared with a pair of HD650, and both me and my father considered that the K701 sounded softer, more open and clearer with a stronger/heavier bass than the HD650 which sounded harder/drier and more confined. We both considered however that the AKG were the best sounding and not too bright/sharp, as they are otherwise known for. Keep in mind that the Sennheiser costs 2-3 times as much.

 

[Mellowship]

Did someone mention "cable mod" on the K701?

I got these for a bargain a few months ago.

Did the bass mod (removed the sticker), changed the internal cables to canare wire and put some 3.5mm panel plugs (this is tricky as a lot of plastic must be filed inside to fit the plug).

A new set of pads and internal foam tuners and a pair of DIY balanced cables (a 4 pin-XLR for the big amp and a 2.5 for the small one), and these play astonishingly well.

 

[mikaelmark]

Nice work!

I also realize they has black cushions and the leather headband having those knockles resting to your head. Do you remember if yours also had black or grey foam in front of the drivers? (I suppose black has higher density than the grey one´s)

It seem´s AKG/Harman has made a lot of different mixes/changes in their K70x -series!

Just a shame those headphones has rather bad build quality, for example if I open my mouth there´s a crackling sound from the plastic housing - however the price/sound/comfort value are very good!

 

[Mellowship]

Nice work!

I also realize they has black cushions and the leather headband having those knockles resting to your head. Do you remember if yours also had black or grey foam in front of the drivers? (I suppose black has higher density than the grey one´s)

It seem´s AKG/Harman has made a lot of different mixes/changes in their K70x -series!

Just a shame those headphones has rather bad build quality, for example if I open my mouth there´s a crackling sound from the plastic housing - however the price/sound/comfort value are very good!

Thanks.
I bought mine second hand, in original state, with totally rotten foam inside the once light grey pads, and completely tired rubber bands. For 35 euros.
The original tuning foams were also rotten.
The new pads and foams are OEM from AliExpress.
The headband has that very uncomfortable padding that pushes down the skull.
These are first or second generation 701, made in Austria.
The build quality is indeed nothing to write home about, but I've seen much worse.

 

[kornel221]

I just have tried the mod on my k702 after reading all the positive responses and recommendations.

I regret doing it , yes it has more bass but the soundstage becomes smaller , the bass seems uncontrolled and the instrument separation is not as good as it used to be I will try to reverse it although I see it difficult to place the stickers exactly as they were placed from factory.

I wouldn't recommend this mod , the k702 are great for their soundstage , detail and instrument separation , after the mod they become different headphone and all their benefits are lost imo.

 

[akilablat]

Interestingly I find this bass mod works best with the foam disk removed from the earcup. The foam disk already muffled the sound quite a bit and if you further remove the sticker on the bass port it might be too much for some people. But for me remove the sticker and foam disk worked the best.

 

[Petrasescu_Lucian]

I have two original Made in Austria AKG K701s and decided (out of boredom) to apply the "bass mod" to one pair.
The mod adds a low frequency rumble to the sound, much like the extra oumph of an uncalibrated subwoofer. Unfortunately, this extra oumph doesn't carry additional information (sound detail if you will) and will muddy the texture and clarity of the bass. Keep in mind that I tested by swapping the two pairs of headphones for every test that I've made so my evaluation doesn't rely on memory nor placebo (I've made a modification so it "must" sound good or else I've wasted my time and energy).
In short, don't do it, it will ruin your excellent mastering headphones.
If you think it sounds better you are either delusional or have corrupt tastes.
If you want more bass regardless of its quality, look to other more "audiofool" or "hi-fi" headphones.

 

[akilablat]

I have two original Made in Austria AKG K701s and decided (out of boredom) to apply the "bass mod" to one pair.
The mod adds a low frequency rumble to the sound, much like the extra oumph of an uncalibrated subwoofer. Unfortunately, this extra oumph doesn't carry additional information (sound detail if you will) and will muddy the texture and clarity of the bass. Keep in mind that I tested by swapping the two pairs of headphones for every test that I've made so my evaluation doesn't rely on memory nor placebo (I've made a modification so it "must" sound good or else I've wasted my time and energy).
In short, don't do it, it will ruin your excellent mastering headphones.
If you think it sounds better you are either delusional or have corrupt tastes.
If you want more bass regardless of its quality, look to other more "audiofool" or "hi-fi" headphones.

And if you care so much about bass quality rather than quantity why not remove the foam disk as well? That thing does the same thing like you said. If you can't handle that you have no right to judge othet's taste as well.

 

[Petrasescu_Lucian]

And if you care so much about bass quality rather than quantity why not remove the foam disk as well? That thing does the same thing like you said. If you can't handle that you have no right to judge othet's taste as well.

Who said I didn't test that either? That circular foam that sits in front of the driver impacts the sound as well but not to the degree of this "mod".
This mod completely destroys the bass quality of the transducers (after all, that sticker was glued there for a reason). It's exactly like an out of phase or uncalibrated subwoofer.
Instead, the circular foam alters only slightly the upper bass and lower midrange section. The foam makes the sound somewhat warmer while this mod destroys the bass in both fidelity and transient response.
I can understand that some people like the headphones with and others without the circular foams (after all sound is a subjective thing and AKG deliberately left the choice to use the foams or not to the users) but we're comparing apples to oranges here, as this mod destroys the very quality that makes the k701 such awesome headphones.

 

[akilablat]

Who said I didn't test that either? That circular foam that sits in front of the driver impacts the sound as well but not to the degree of this "mod".
This mod completely destroys the bass quality of the transducers (after all, that sticker was glued there for a reason). It's exactly like an out of phase or uncalibrated subwoofer.
Instead, the circular foam alters only slightly the upper bass and lower midrange section. The foam makes the sound somewhat warmer while this mod destroys the bass in both fidelity and transient response.
I can understand that some people like the headphones with and others without the circular foams (after all sound is a subjective thing and AKG deliberately left the choice to use the foams or not to the users) but we're comparing apples to oranges here, as this mod destroys the very quality that makes the k701 such awesome headphones.

Not agree at all, it also depends on what you using to drive this headphone. This thing can sound like a orange and apple just on a different set so your point is worthless. I did the experiment as well using 2 different amps and have different preference. But I never liked the stock sound on any of them. It's harsh and dry doesn't have any kind of immersive feeling and the vocal is too close. Kind of reminds me of balanced armature sound. The fully open mod on one amp sound too loose to me and with cotton tissue cover it sounded the best, better than stock. On the other amp the fully open sounded the best. I'll just suggest everyone to try fully open and different materials, if you like it you keep it if no you can always go back.

 

[Petrasescu_Lucian]

And we're are talking about apples and oranges here !
You are talking about frequency response, me about dynamics and transient response.
This mod destroys the latter. If you want the former, try experimenting with different ear pads or foam pads or, better yet, find a better dac/amp combo.
Speaking of which, I drive my K701s through the Lynx Hilo:
https://www.thomann.de/gb/lynx_studio_hilo.htm
The sound is extremely dynamic, loud, punchy, analytical and faster and more detailed than the K812 and HD800s that I've also tried on the Hilo.

 

[akilablat]

And we're are talking about apples and oranges here !
You are talking about frequency response, me about dynamics and transient response.
This mod destroys the latter. If you want the former, try experimenting with different ear pads or foam pads or, better yet, find a better dac/amp combo.
Speaking of which, I drive my K701s through the Lynx Hilo:
https://www.thomann.de/gb/lynx_studio_hilo.htm
The sound is extremely dynamic, loud, punchy, analytical and faster and more detailed than the K812 and HD800s that I've also tried on the Hilo.

Bruh I don't like to comment on someone's taste but once you said it's faster and more detailed than k812 and HD800 it's not a good sign for me. I tried these headphones before and they were already right on the edge for me. Not everyone like overly fast and analytical sound you should respect other's taste. And like I said your driving device matters a lot not everyone gonna use that kind of crazy expansive device with 150$ headphone like you did.....I don't know how it sounds but I only bought this headphone because it's one of the best budget options out there. With that being said I don't have much budget for Dac/Amp as well. I believe this is also the case for lots of other people. And this mod does work well for my cheap devices that's all what matters to me.