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What is the difference between A-Series and U-Series?

A-Series is our line of custom in-ear monitors, specifically made to the shape of your ear. U-Series is our line of universal-fit earphones that fit to anyone's ear. Our universal earphones come with various ear tips to fit different size ears.

I've never worn Custom In-Ear Monitors, how do they feel?

If you've never worn custom earphones, it may take a little while for your ear to get used to something being in it. What to look for is discomfort or pain from wearing them. If you don't feel any sharp pain, just give your ears a little time to get used to them and you'll forget that you have them in.

If the pain or discomfort continues, try the troubleshooting steps from our support page, or open a support case from you Customer Account. We will work with you to adjust your custom in-ears monitors accordingly.

Who is an Audiologist?

An audiologist is a professional who diagnoses and treats hearing and balance problems. An audiologist has received an Au.D. (Doctorate in Audiology), or a Master's or Doctoral degree from an accredited university graduate program in audiology. They are also trained to take deep ear impressions. This kind of "deep" ear impression is required by 64 Audio in order to build your custom set of in-ear monitors (see our How to Order page).

All service fees are paid directly to the audiologist and cannot be billed to 64 Audio.

What happens to my ear impressions after I send them to 64 Audio?

Each ear impression is scanned, electronically filed, and matched to its corresponding order. Once the order is shipped, the ear impressions are properly disposed of by 64 Audio.

Because your ears grow and change over time, you may need to get new ear impressions every few years to maintain the perfect fit.

How long do you make the canal on your Custom In-Ear Monitors?

The length of the canals on our custom earphones goes past the second bend in the ear. We make them as long as possible without causing discomfort to your inner ear.

What material are your Custom In-Ear Monitors made of?

The shells are made of hypoallergenic, hard acrylic plastic for durability and longevity.

Do you offer custom artwork? Which format do you require?

If you would like artwork printed on your IEM faceplate, we accept high quality PNG, JPG, or GIF files. For best results, use PNG files with background removed (transparency layer). Artwork cannot be uploaded on certain faceplates, which are indicated in the Designer. File sizes must be smaller than 2 MB. We recommend using Chrome, Safari, or Firefox web browsers with the custom artwork function. You can upload your custom artwork in the Designer when placing your order. Custom artwork is an additional cost per side.

What are recessed sockets?

Recessed sockets help the cable and connector to last longer. The recessed connectors are deeper into the shell and the cable is held more securely thereby limiting wear and tear on the connectors. This improves the durability of the connection and prolongs the life of both the socket and cable connectors. All A-Series models come standard with recessed sockets. There are some cases where recessed sockets are not possible due to shape and size of ear, we will continue to make your product with the normal socket. This doesn’t affect the sound or function of the product.

How long is the build time for Custom In-Ear Monitors?

The build time is an estimate and varies depending on the product and the number of orders currently in the queue. You can check the build time for your particular model by visiting the product page.

Please note that the build time begins once we receive your ear impressions and they are approved. For more information, visit our How to Order page.

Can I get my Custom In-Ear Monitors faster?

We offer a rush build for an additional fee. This can be selected in the Designer as you're building you Custom In-Ear Monitors.

Can I remold a pair of 64 Audio Custom In-Ear Monitors that I got from someone else?

No, we only remold 64 Audio CIEMs for their original owners. This is to minimize the chance that CIEMs are stolen and remade without the original owner's knowledge. Note that we do not remold in-ear monitors from other manufacturers. Visit the support page for more information.

All service and repair work is now done as a flat fee, which varies depending on the model of IEM.

Can I remold my U-Series into Custom IEM?

No, we are only able to remold the A-Series Custom IEMs.

I have an issue with my earphones, where can I troubleshoot the problem?

You can troubleshoot the issue by going to our Support page. If you’re not able to troubleshoot and solve the issue, you can create a support case from you Customer Account. If needed, you'll be instructed to send your IEM to the 64 Audio lab for further diagnosis and repair.

I have a fit issue with my Custom In-Ear Monitors and need an adjustment.

Because of the many variables that take part in creating a custom product, sometimes the need for a fit adjustment is inevitable. We will refit your product or rebuild your earphones at our discretion.

Create a support case from you Customer Account and send your IEM or earplugs to our lab within 30 days post receipt of your order to be covered by the 30 Day Fit Guarantee. 64 AUDIO covers the labor costs and shipping the refitted earphones from the lab back to the customer. The cost of shipping your product to our lab is NOT covered by 64 AUDIO.

I need a refit, can a local audiologist make the adjustments?

64 Audio cannot cover the fit of your product under warranty after an audiologist has altered it. In regards to the internal components, your warranty will still be in effect, EXCEPT for any damage the audiologist may cause. We cannot warranty any damage done by the audiologist, including the external shell and the internal components.

What shipping service do you use for international orders?

We use FedEx International Priority (2-3 business days to most countries).

How do I fix a fit issue as an international customer?

Please email us at before working with a third-party, so we can let you know how it may impact your warranty and what we recommend to resolve the issue.

If the issue just involves trimming down a section that is causing discomfort, you can save on shipping time and costs by taking it to your local audiologist. If they have apex tools available to make adjustments to hearing aids, they'll likely be able to make small adjustments to your CIEM.

What is apex®?

Apex is a pneumatically interactive vent that relieves pneumatic pressure (also known as air pressure) caused by miniature speakers in a sealed ear canal. With apex, this pressure is greatly reduced, the sound quality is improved, and the stereo image is much wider. This technology minimizes ear fatigue and provides a safer listening experience as well as a richer, more spacious sound when compared to conventional in ear products. In addition, instrument separation is more distinguishable because the sound is delivered to your eardrum in a more natural way. Learn more on our apex technology page.

Is apex® compatible with my A-Series or U-Series earphones that I purchased earlier?

If you are the owner of an original A-Series or U-Series product, we thought that you might want to experience the benefits of the new modules. We’re glad to say that the new apex modules are backwards compatible with all previously shipped A-Series & U-Series in-ear monitors (IEMs).

What are those orange solid plugs in the Custom Earplugs?

The orange solid plugs is used in our Custom Earplugs to achieve maximum isolation, -26dB. Although it looks like an apex module it does not contain the pressure relief function of our apex modules and is not intended for use with any of our IEMs. All of our Custom and Universal IEMs are designed with the apex technology and achieve their intended sound signature and optimal function with apex modules installed. If you need to replace a solid plug or otherwise acquire one, please contact customer support.

What is the warranty on my product?

Please see our Warranty page.

What are your terms and conditions?

Please see our Terms and Conditions page.