M-Audio Q40 vs. Equation RP-21 vs. AKG K240 quick review
Aug 24, 2008 at 8:54 PM Thread Starter Post #1 of 24

ounkchicago

100+ Head-Fier
Joined
Jun 28, 2007
Posts
239
Likes
0
Here is my quick review of these three cans. I was supposed to post an in-depth review a few months back, but I haven't had the time to do the careful listening.

Cans reviewed:
1. M-Audio Studiophile Q40
2. Equation Audio RP-21
3. AKG K240 Studio (stock cable, Stefan Audio Art Equinox cable)

Sources used:
1. Apple iMac G5 headphone out
2. Sansa Clip
3. E-MU 0404 USB (headphone out)

Benchmark System:
Cambridge 840C--> LD MKIV SE --> M-Audio BX8a studio monitors / AKG K701 / Beyer DT880


1. M-Audio Studiophile Q40. Price paid: $125 street

The Q40 is a closed headphone designed for studio use. It has the highest SQ (sound quality) of these 3, with a very flat frequency response. It sounds the most realistic and least colored, and it seems like M-Audio didn't try to imbue it with any special "audiophile" powers. The Q40 is also the bass monster of this group. It has the deepest, loudest, and most accurate bass. In fact, its bass performance also exceeded that of my K701 and DT880.

This headphone doesn't need amplification at all, and is efficient enough to use straight out of the headphone jack of a computer or an DAP (digital audio player). The SQ will scale only slightly when using an amp... using a very powerful amp will produce absolutely thunderous bass.

The Q40 is comfortable for the first 20 minutes of listening, but after that the high clamping force becomes noticeable. It clamps the hardest and provides the best isolation of the 3, but has the lowest long-term comfort. The headphones look very modern and attractive, definitely the best looking of the bunch here. It has a screw-type detachable cable which has a good length and is not microphonic. The headphones also fold up and come with a handy carrying case.


2. Equation RP-21 Price paid: $100 street

The RP-21 also seems intended for studio application, with a closed design. It aims for a flat frequency response rather than an audiophile experience, but it comes up short. While the bass and the lower mids are fairly accurate, the treble has a persistent inaccuracy to it that significantly degrades the listening experience.

Like the Q40, the RP-21 is efficient enough to be used straight out of most headphone jacks. It benefits the least from amplification of these 3.

The RP-21 clamps hard out of the box, but as you stretch out the headband it becomes more comfortable. Its clamping force is more comfortable than the Q40, but the headband isn't well padded. Still, for long listening periods, the RP-21 should be slightly more comfortable than the Q40. It doesn't isolate as well as the Q40... I found these cans to provide insufficient isolation for train use. Also, when you wear these, you will look somewhat like an alien to other people. The cable is detachable, but it has a locking notch going into the headphone. This means that aftermarket cabling would be difficult to find. The drivers rotate 90 degrees for portability, and the cans seem to be able to take a beating. However, as some other Head-Fiers have noticed, the headband quality seems to be rather poor, and after a month or so you may notice the sticky part of the headband beginning to show, where the top piece of the headband meets the adjustment for head size.


3. AKG K240 Studio Price paid: $100 street

The AKG K240 Studio is the oldest and the most popular of these three headphones. While it is marketed as a studio headphone, it does not have a conventional closed design. Instead, it utilizes a semi-open design. This means that you will have very little isolation, and sound will leak out of these slightly at moderate to high listening volumes.

I have a love-hate relationship with the K240's sound. By far, the best feature of the K240 is its life-like reproduction of mids (a.k.a. the "AKG mids"). This makes most of the focal lead instruments, such as guitar or piano, sound exceptional. But the frequency response is not flat, even though this is supposed to be a studio headphone. Its main problems are a bloated, inaccurate, and slow bass reproduction that can't keep up with fast music. It also has rolled off treble response, which reduces the high-end detail but also virtually eliminates sibilance and listener fatigue.

The K240 requires amplification to sound right. Out of a DAP or computer headphone out, the K240 may disappoint. Although are not particularly inefficient, they do seem to require large amounts of power to sound their best.

The K240 is the most comfortable headphone here by a longshot. It employs a self-adjusting headband, and the clamping force is low. But as noted before, isolation is near zero. They have a retro style to them that may draw attention to them, but they don't look as dorky as the RP-21. They have a detachable cable which uses a mini-XLR plug, which allows for aftermarket upgrades.

Rumor has it that the stock cable for the K240 contributes to the muddy, bloated, inaccurate bass that plagues these headphones. One solution to this problem would be to replace the stock cable with a Stefan Audioart Equinox cable (price paid: $90 used for a 6-foot cable). The Equinox cable is compatible with the entire Studio series (basically anything with a mini-XLR connector) and is voiced specifically for AKG.

So the big question is, does the Equinox cable solve the K240's sound problems? The answer is yes, but not without compromises. The Equinox cable results in a huge increase in SQ... treble is less rolled off, mids are still as excellent as ever, and bass is now tight, although not very impactful. So if you like the classic AKG sound you would probably like this upgrade a lot. But you pay a price for this. The first price is, well, the price.... this cable costs over $100 new, which is more than the K240 itself. So altogether you're looking at a setup that exceeds $200. The second price is the thickness and microphonic nature of the Equinox cable. While not a dealbreaker, it is pretty annoying that every time I move I hear the friction of the cable through the headphones.


Conclusion

Sound Quality: The Q40 is the clear winner here, with its balanced sound and its powerful bass. The K240 has the most "fun sound," with its killer mids and non-fatiguing, rolled off treble, but with bloaty inaccurate bass. The RP-21 is the least satisfying of the 3 but is more accurate than the K240.

Comfort: The K240 is the clear winner here... the only can that can be used for hours without discomfort.

Isolation and Portability: The Q40 has the best isolation and is very portable. The RP-21 comes in a close 2nd. The K240 doesn't fold and leaks too much sound to be used as a portable.

Overall Pick: I think the Q40 is the clear winner in this roundup, but it still has its flaws. It may be uncomfortable to wear for a long period of time. While it has a very accurate sound, audiophiles may find this "flat" frequency response curve to be too dull and unembellished.

The RP-21 does everything reasonably well, but doesn't excel in any areas. Because of this, I would choose the Q40 over the RP-21.

The K240 is the troublemaker of the bunch. From an objective standpoint, it comes up short. It doesn't have a very accurate sound, its bass can't keep up with fast music (such as techno), it won't sound very good without amplification, and it's not portable at all.

But despite all its shortcomings, I refuse to part with my K240. These cans are supremely comfortable for their category, both in terms of physical comfort and having a non-fatiguing sound signature. And although they leak sound, under low to moderate listening volumes, you could still use these in a cubicle farm (but not in a library). So the K240 Studio wins an honorable mention for dutiful service, and they will continue to be the cans I use most at work.
 
Aug 25, 2008 at 12:22 AM Post #2 of 24
In regards to the clamping force of the Q40s: It can be rectified by bending the headband. There are two metal bands that run inside the headband. They are not plastic. Therefore, you can stretch them open little by little.

The other thing for me that makes the Q40s an outstanding value is their build. I have worked on a lot of different headphones and the build quality of the M-Audios is second only to Beyerdynamic. For example, the hinge where the ear chambers fold into the headband is metal. You just don't see this. Even the uber expensive Ultrasone Edition 9 is all plastic.

Glad to hear there's is another fan of the Q40s.
smile.gif
 
Aug 25, 2008 at 2:01 AM Post #3 of 24
Quote:

Originally Posted by warrior05 /img/forum/go_quote.gif
The other thing for me that makes the Q40s an outstanding value is their build. I have worked on a lot of different headphones and the build quality of the M-Audios is second only to Beyerdynamic. For example, the hinge where the ear chambers fold into the headband is metal. You just don't see this. Even the uber expensive Ultrasone Edition 9 is all plastic.

Glad to hear there's is another fan of the Q40s.
smile.gif



In this comparo, the Q40 seems like it has the highest overall build quality. I expect it to be as durable as my Beyers. But the K240 also has exceptional build quality. The RP-21 seems to have the worst build quality of the 3. There is a part on the headband where some adhesive compound is showing through... not a good sign for a headphone that hasn't logged many hours. Additionally, the hinges that rotate the drivers are made of plastic, and they will probably be the first to break.

One minor issue so far with the Q40. I have already developed one small tear on one of my earpads. I cannot determine the exact cause, but i have treated the cans the same way as my K240. I have also logged about 10x as many hours on my K240. So as far as the earpads are concerned, I think that the AKG earpads appear to be more durable than the Q40 earpads.
 
Aug 25, 2008 at 2:54 AM Post #4 of 24
Quote:

Originally Posted by ounkchicago /img/forum/go_quote.gif
In this comparo, the Q40 seems like it has the highest overall build quality. I expect it to be as durable as my Beyers. But the K240 also has exceptional build quality. The RP-21 seems to have the worst build quality of the 3. There is a part on the headband where some adhesive compound is showing through... not a good sign for a headphone that hasn't logged many hours. Additionally, the hinges that rotate the drivers are made of plastic, and they will probably be the first to break.

One minor issue so far with the Q40. I have already developed one small tear on one of my earpads. I cannot determine the exact cause, but i have treated the cans the same way as my K240. I have also logged about 10x as many hours on my K240. So as far as the earpads are concerned, I think that the AKG earpads appear to be more durable than the Q40 earpads.



Totally agree. One of my first changes to the Q40s was replacing the earpads with a pair of Beyer's. One of my gripes about the M-Audios is they did use cheap thin pleather for the earpads and the headband. My other gripe is the stock cable. Hated it and made one to replace it the first day I had them.
 
Aug 25, 2008 at 1:17 PM Post #5 of 24
While I haven't heard the other two, I must agree that it is a fine headphone, especially considering how inexpensive they can be.

Complaints? Well, I'll second the original cable is junk and needs to be replaced A.S.A.P. Other than that, I find they tend to rub on the ears a bit with the original earpads on. Haven't tried those Beyer pads yet, though.
smily_headphones1.gif
 
Aug 25, 2008 at 4:37 PM Post #7 of 24
I love my Q40s. I had the chance to listen to some Grados and Audio Technica phones this weekend at the Audio Cubes store. In my opinion, the Q40 is overall better than all of them, even the higher end ATs (or rather, I prefer the Q40 sound sig over the Grados and ATs).

In terms of cable, do you guys mean it's junk in terms of build quality or sound quality? Should I find a way to replace my stock cable, and would that improve on the already awesome sound?
 
Aug 25, 2008 at 4:52 PM Post #8 of 24
Quote:

Originally Posted by fuzzylogic76 /img/forum/go_quote.gif
In terms of cable, do you guys mean it's junk in terms of build quality or sound quality? Should I find a way to replace my stock cable, and would that improve on the already awesome sound?


The build quality does not match the headphones they attach to at all. One of the jacks on mine went out within a week, and it's stock replacement did the exact same.
 
Aug 25, 2008 at 8:00 PM Post #10 of 24
I have not experienced ANY problems with my stock cable. I wonder whether this is a quality control issue rather than a design issue (maybe my cable came from a batch of good ones, whereas yours came form a batch of bad ones, etc.).

When you replaced the stock cable with an aftermarket one, did you notice any increase or change in SQ?
 
Aug 25, 2008 at 8:02 PM Post #11 of 24
I've also ordered a pair of Denon AH-D1001 because they are so inexpensive now. I am hoping they outperform both the RP-21 and K240 in terms of SQ, comfort, and portability. I do not expect them to beat the Q40 in SQ, but they are much lighter and supposedly more comfortable for long duration and portable use (less than 6.5 ounces).
 
Aug 25, 2008 at 8:19 PM Post #12 of 24
Quote:

Originally Posted by ounkchicago /img/forum/go_quote.gif
I've also ordered a pair of Denon AH-D1001 because they are so inexpensive now. I am hoping they outperform both the RP-21 and K240 in terms of SQ, comfort, and portability. I do not expect them to beat the Q40 in SQ, but they are much lighter and supposedly more comfortable for long duration and portable use (less than 6.5 ounces).


Keep in mind that the Denons are not meant to be monitors like those in your initial comparo. They definitely bring a colored SQ to the table which may or may not float your boat. Comparing them to the three monitors is a bit apples and oranges IMO. Though most tend not to pay attention to the distinction.

I'm babbling. Ignore me.
rolleyes.gif
 
Aug 25, 2008 at 8:24 PM Post #13 of 24
Quote:

Originally Posted by warrior05 /img/forum/go_quote.gif
Keep in mind that the Denons are not meant to be monitors like those in your initial comparo. They definitely bring a colored SQ to the table which may or may not float your boat. Comparing them to the three monitors is a bit apples and oranges IMO. Though most tend not to pay attention to the distinction.

I'm babbling. Ignore me.
rolleyes.gif



Of the headphones in my comparo, I think only the Q40 deserve to be called Studio monitors. The other two may have the form factor of a studio monitor, but I would advise against having them used as such. I've always wondered why the K240 has had such a longstanding role as being one of the "giants" of the studio monitor headphone kingdom. In my mind, I thought that the highly colored nature of the K240 would lead to bad post-production products.

Then again, there is a lot of theory about what makes a good studio monitor, and it's true that not everyone agrees on what good qualities a studio monitor should have. For example, one camp seems to believe that a good studio monitor should have a flat frequency response, whereas another camp seems to believe that a good studio monitor should be close to the average/median headphone/speaker. Clearly these two are not the same.
 
Nov 17, 2008 at 2:31 PM Post #15 of 24
Quote:

Originally Posted by john5220 /img/forum/go_quote.gif
its bass performance also exceeded that of my K701 and DT880.


DUDE ARE YOU SERIOUS?



Yes I'm serious, considering I was never really impressed with the bass of my K701 and DT880.

Don't get me wrong though, I still prefer the K701 to the Q40 for overall listening (open design, lower clamping force, pleasantly colored sound, great soundstage). I was just focusing on one attribute -- the bass, and using the K701 and DT880 as benchmarks to put the Q40 in perspective.
 

Users who are viewing this thread

Back
Top