Upgrade Cables for Moondrop, Truthear, 7Hz and Other Budget IEMs

Almost every current Moondrop, Truthear, 7Hz, Kiwi Ears and Simgot model among today's budget IEMs uses a 0.78 mm 2-pin connector, often in a recessed socket. A standard 0.78 mm 2-pin cable fits them all. Watch for two exceptions: older MMCX models, such as the original 7Hz Timeless and most Tin HiFi T2 versions, and qdc-style extended sockets on many KZ models.

Budget IEMs have become very good, and their stock cables are usually the weakest part of the package: thin, springy and prone to tangling. This guide is for owners who want a better cable without guessing. You'll find a connector chart for popular models, what a replacement cable really changes, and which Null Audio cable fits which use.

Which connector do budget IEMs use?

A connector is the plug-and-socket joint where the cable meets each earpiece. On budget IEMs it is usually 0.78 mm 2-pin. The chart below covers popular models from six brands.

Manufacturer pages confirm several of these, including the Moondrop Blessing 3, Truthear Hexa, Kiwi Ears Cadenza and 7Hz Timeless II, released in 2025. Makers sometimes change connectors between versions. If your model isn't listed, look it up in Find My Cable, which covers over 400 IEMs, or send us a photo of the socket.

Do recessed sockets need a special plug?

No. A recessed socket is a 2-pin socket set slightly below the shell surface, while a flat (flush) socket sits level with it. Our standard 2PIN (0.78) plug is made to seat fully in both.

The plug to avoid is a qdc-style "extended" 2-pin. Its pins sit inside a raised shroud designed for a different socket shape. Headphonesty's Simgot EA500 review notes that a qdc plug won't seat on a standard recessed 2-pin socket. Our IEM cable connector guide explains every type in detail.

MMCX and qdc-style exceptions

MMCX is a snap-on coaxial connector that lets the earpiece rotate. It has a reputation for wear and loosening with frequent swaps. Audio-Technica lists loose fit, overly tight fit and dropouts when rotating as common MMCX problems (Audio-Technica). If your budget IEM uses MMCX, choose MMCX in the configurator and avoid swapping cables more than you need to.

KZ's "C-pin" is a qdc-style extended 2-pin used on the ZSN Pro, ZSN Pro X and ZS10 Pro (ConceptKart). The Simgot EM6L uses a qdc-style socket too. For these, contact us before ordering. Older UE and Unique Melody models use a related legacy plug, listed as UE/UM/QDC 2PIN Legacy.

Is an upgrade cable worth it on budget IEMs?

Often, yes, but mainly for practical reasons. A replacement cable improves how budget IEMs wear, handle and connect. Here is what actually changes.

Comfort and handling

A softer cable with good ear guides sits better and tangles less. It also transmits less rubbing noise into your ears. That noise is called microphonics: sound carried up the cable when it rubs or moves.

Durability

Stronger strain relief, better plugs and a tougher jacket last longer than most stock cables. Every Null Audio cable has a 1-year warranty against defects in materials and workmanship. Arete, Ethos Ultra and Lune bought within 3 years also qualify for flat-rate repair at USD 30. Brevity is not covered by flat-rate repair. See our warranty page.

The right plug

You can switch to 4.4 mm balanced for a dongle or player with a balanced output. You can also choose a USB-C DAC plug for a phone without a headphone jack. See 3.5 mm, 2.5 mm or 4.4 mm balanced? and using IEMs with your phone.

Resistance

A typical IEM cable measures under about an ohm. Rod Elliott measured a normal cable at 0.2 ohms against a deliberately resistive one at 10.9 ohms (Elliott Sound Products). With low-impedance multi-driver IEMs, extra series resistance can slightly shift the frequency response. A thicker cable keeps it closer to how the IEM was tuned. We explain why in Do IEM upgrade cables make a difference?

Which Null Audio cable suits budget IEMs?

Match the cable to how you'll use it rather than to the IEM's price. The table compares our four most popular choices for budget IEMs.

• Brevity Pro is soft and light, with little memory and a slim 3.5 mm plug that fits most phone cases. The default 2-pin version ships within 2 working days.
• Ethos Ultra is a coaxial cable with a detachable player end. Its 3.5 mm, 4.4 mm balanced and USB-C DAC plugs all come in the box.
• Arete MKV is the second longest-running cable in our range. We describe its sound as dynamic, with deep bass.
• Lune MKVIII has been a best-seller for 15 years running. It uses 53 strands per wire in a custom Litz configuration.

Curious about materials? Our guide to copper vs silver IEM cables explains what each conductor really changes.

How to fit a new cable safely

A few habits protect both the IEM and the cable.

• Pull the plug straight out of the socket. Don't lever it sideways.
• Match polarity on 2-pin plugs. Line up the marked side on both earpieces; reversing one side puts it out of phase.
• Push 2-pin plugs in until they seat fully, including in recessed sockets.
• Swap MMCX cables only when you need to, since frequent swaps wear the joint.

Find the right cable for your IEM

Every Null Audio cable is built to order in Singapore with the connector and plug you choose. Shipping by FedEx is free worldwide from USD 250.

Start with Find My Cable to confirm your connector, or browse all IEM and headphone cables. Not sure? Ask us with your IEM and player, and we'll suggest a match.

Frequently asked questions