MMCX vs 2 Pin Cables for IEM | IEM 101

Latest IEMs feature detachable cables with two different types of connectors, MMCX and 2-Pin. The MMCX connectors provide a more strong connection, the cable snaps into the ports with a producing a clicking sound. It locks in the cable and earpieces securely. Two-pin connectors are of two types, straight pin, and angled QDC pin. As evident from the name straight pin features two straight pins, the QDC variant has angular 2-pins with a covering. Two-pin connectors are of two sizes, 0.75mm, and 0.78mm. Users should always check the connector type on their IEM first before ordering a cable. Even though they don’t affect the sound quality of your earphones in any way, they surely have their own pros and cons.

2Pin 0.78mm

  • Two-Pin connectors are of two types, straight pin and angled QDC pin. Both the variants come in two different sizes, 0.75mm and 0.78mm. Users can buy the one matching with their IEMs. There is no lock-in mechanism and the pins are delicate. They are so light that one can turn the pins with their fingers by applying a little pressure. These connectors are very prone to get damaged, even while putting the IEMs in cases some pressure might get applied at the connector points and they might get damaged. But this issue got solved with the introduction of QDC two-pin connectors as they have a covering around the angled connectors. The main issue with QDC two-pin connectors is since the connectors are angled, these are not suitable for IEMs that are worn in the “Cable Down” way. Two-Pin cables can be connected in reverse polarity mode, connecting the left side of the cable to the right Earpiece and vice versa. Reverse Polarity affects the sound output in most of the cases as the current gets mirrored. This messes up the sound quality heavily and makes the pair sound weird.

Pros of Two-Pin Connectors:-

>The connection is firm, earpieces don’t rotate around on the cable.

>Cheaper than MMCX connectors.

>Easy to change cables without any hassle.

Cons of Two-Pin connectors:-

>Delicate and prone to get damaged easily.

>Could be connected in opposite points, Right side of the cable to the left earpiece and vice versa, resulting in reverse polarity that might damage earphone driver.


  • MMCX connectors provide a more secure connection between the cable and the earpieces with a snap-in locking mechanism. Mostly new IEMs have gold-plated MMCX connectors. Even though they are preferred mostly, they are more suitable with IEMS that are supposed to be worn in the “Cable Down” way, probably due to the aforementioned Lock-in mechanism that prevents the weight or strain to pull out the cable from the earpieces. But this lock-in mechanism is not always good, sometimes it is very tight and it becomes very hard to change the cable. Applying force might result in a breakage of the connector ports on the cable or earpieces.

mmcx connector

Pros of MMCX connectors:-

>Safe and secure connection.

>Suitable for IEMs with any wearing method, around the ear or cable down.

>Earpieces can rotate around while connected.

>Can only be used with the proper right sides, reverse polarity is not possible.

Cons of MMCX connectors:-

>Costly as compared to Two-pin connectors.

>In some cases the lock-in mechanism is very tight and trying to pull out the cable sometimes damages the connectors on both ends.

Even though these two are entirely different from each other, there is no difference in sound quality output due to different connector types. Here are a few aftermarket cables to look for while upgrading.

More to explorer

Audio Terms Defined

Audio Terms Defined and Explained When entering the audiophile world or even if you’ve been in it for a while now, you’ll most likely come

Read More »

Kinera Tyr Review Round Up

China-based Kinera has made waves with their range of earphones over the years ranging from super budget to premium with their electrostatic flagship Nanna. With

Read More »


There is nothing laid back about the Nanna sound but neither does it sound edgy or harsh with just a slight hint of upper-most treble

Read More »