How are iems tuned?

Submitted by BWJackal t3_126unnd in headphones

I recently watched this video and it was stated that iems are usually tuned using dampeners and that the KZ ZVX is tuned using chip capacitors. In what other way(s) can iems tuned?

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Egoexpo t1_jeb36hk wrote

Yes, they can use some analog EQ inside the IEM (with or without multiple drivers, Crossover=EQ) to change the sound or a DSP (digital EQ).

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BWJackal OP t1_jeb4zg5 wrote

Replying to Egoexpo (#2,495,547)

Are analog eq, crossover, and using chip capacitors the same? If not, can you explain what analog eq and crossover are?

 

Edit: I think I figured it out. Just to clarify, both crossover and using chip capacitors are forms of analog eq, but the latter only applies to hybrid iems?

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TagalogON t1_jebucr0 wrote

Crinacle recently (this just passed its 1 year anniversary, lol) did an interview about how his collaborations (KZ CRN/ZEX Pro, Moondrop Blessing 2: Dusk, etc.) kinda came to be: https://www.youtube.com/watch?v=-2PrHgoU0Q0&t=249s

Search up Delta Fyre, Hi-Fri Audio, etc. Those people on Facebook that do teardowns/dissections/etc. of IEMs. They'll show you the drivers being used, the dampening measures, the crossovers, etc.

Right now the Simgot EA500 is receiving a lot of hype and due to the removable nozzle, some people are doing tuning foam mods and so on. Some people are also using the removable nozzle of the Moondrop Kato and so on with the EA500.

To replace the filter/mesh/et cetera, usually those are like $2-5+ from AliExpress. So just need to wait a few weeks. Maybe they're on Amazon too, check around there sometimes, you might need to use specific keywords for them to show up.

Usually people use say 400-500 for the size/etc. of the meshes/etc.

See here for a bit more info about tuning foams/meshes/et cetera: https://www.reddit.com/r/headphones/comments/vpljd3/dioko_update_good_to_see_crinacle_taking_a_more/iekb7li/ and https://www.reddit.com/r/HeadphoneAdvice/comments/11wu2qo/losing_volume_in_left_earbud_after_only_2_months/jd3q92t/. Check RikudouGoku's posts/threads on Head-Fi and HiFiGuides.

Some companies are also producing DSP versions of their IEMs, but people say there's inherent delays/interferences/etc. with playback and like buzzing/static/etc. with them. See here for some threads about those DSP IEMs: https://www.reddit.com/r/headphones/comments/11xvoqu/moondrops_dsps_defective_quarks_dsp/ and https://www.reddit.com/r/headphones/comments/1164nep/moondrop_quarks_dsp_not_quite_as_good_as_we/

Here's Timmy from Gizaudio talking about the DSP IEMs issues: https://www.youtube.com/watch?v=wKs_-d26WXA

Don't forget ear tips. They can make or break the sound quality due to the treble resonances from the insertion depth, et cetera.

These days a lot of ear tips are medical grade silicone and they are often so thin/etc. that the bass is noticeably altered or reduced.

Info about the Moondrop Spring, TRN T, ear tips that can warp easily to break the seal/fit, et cetera: https://www.reddit.com/r/HeadphoneAdvice/comments/11spulp/believe_in_audio_improvement_claims_of_eartips_or/jcfo5z1/

Click this sentence for more info on the importance of ear tips sizing, dimensions, et cetera.

Click this sentence for more info on foam ear tips durability and sound changes.

Click this sentence for comfort and everything with ear tips.

Click this sentence for how to put ear tips on wide nozzles (basically aim it at different angles and force it, be careful not to overdo it as it can damage the core/stem/stalk/etc. of the ear tips).

This is how you should use Etymotics or really any IEM or TWS earbud to make sure you have that good/perfect fit for that vacuum seal (necessary for the bass to be properly produced): https://www.youtube.com/watch?v=8KwXEqe6Gq4

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dantatata t1_jeca3zk wrote

i’m not an expert but i’ve tinkered with iems and have made my own. heres a simplified version of what i’ve learned in order of increasing complexity (take it with a grain of salt):

  1. adding resistance in front of the driver, i.e. filters and dampers - these tend to affect high frequencies more. a thicker filter dampens the treble more

  2. front and back volumes - allowing air to more freely flow behind the driver allows the driver diaphragm to move. so adding a vent behind the driver can increase bass. you can also add filters in front of the vent hole to fine tune the amount of air you want to let in. adding a vent in front of the driver rolls off the bass, kind of like having a bad seal, but in a controlled manner

  3. tube and nozzle dimensions - longer tubes/nozzles shift peaks to the left. larger diameters increase those peaks. diameter also plays a role by affecting resistance—narrower diameters lower the treble. this is why you see bass drivers have long, narrow sound bores

  4. multiple drivers - drivers have their own properties and resonance frequencies. you can take advantage of this by combining them and tuning them further using the methods above. you may also use a crossover to divide the frequencies

  5. helmholtz resonators and acoustic side branches - for example, the sennheiser ie900, which has helmholtz resonators to absorb certain frequencies. these are side chambers in the sound path. a cool way of thinking about this is considering the properties of the chambers as acoustic analogues to electrical components. the chamber acts as a capacitor, the length and diameter of the channel impact impedance, and dampers act as resistance. by combining and tuning these things, you can approximate the acoustic version of RLC circuits, kind of like a crossover

of course, there’s also DSP and tips, like others have mentioned. i’ll also add that tuning balance armature drivers is more accessible to DIYers since there are fewer things to worry about. with dynamic drivers, there are more factors such as diaphragm material, housing material, cavity shapes and sizes, reflections, etc.

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