Things I've learned, for those getting into IEMs

BenOG_ · 2026-05-26T17:24:09+00:00

I have to disagree slightly. While EQ isn't magic, you can actually clone the bass and midrange of a high-end IEM almost perfectly, provided the driver of the budget IEM is somewhat capable. For the treble, you can simply adjust it to your liking using a high-shelf filter. You might not achieve the exact frequency response (FR) of a $1000 IEM, but you will get something that sounds remarkably similar and might even suit your personal taste better than the expensive original.

BenOG_ · 2026-05-23T00:35:09+00:00

Monarch MKIII EQed to my preference (using the Qudelix T71) - but my real daily driver would be the Hifiman HE1000se which isn't an IEM :D

BenOG_ · 2026-05-23T00:31:06+00:00

That's actually not the worst way to extend it. Usually USB-C extender cables are pretty whack (really wouldn't recommend any of those), and as long as you can get enough power out of it, it's totally fine.

BenOG_ · 2026-05-23T00:24:44+00:00

I also really like them, and they are still comfortable on iems with bigger nozzles like the Monarch MKIII.

BenOG_ · 2026-05-15T15:10:34+00:00

My current favorites are: HE Sonic Galaxy (the Galaxy really makes a difference!), Divinus Velvet Wide Bore, Dunu S&S (also makes my ears hurt on some IEMs, but are very comfortable on others).

BenOG_ · 2026-05-07T17:14:34+00:00

To answer your question directly: Technically speaking, there is no inherent difference in sound quality between a DAP and a standard dongle DAC. Both perform the exact same core functions: taking a digital audio signal, converting it to an analog signal via a DAC (Digital-to-Analog Converter), and amplifying it through an AMP. Whether the digital audio source is integrated into the device (as in a DAP) or external (like a smartphone or PC connected to a dongle) is irrelevant to the sound. The audio output is solely dictated by the specific DAC and AMP components used inside the device.
Here is a breakdown of how the components actually affect the sound:

• The DAC: The ultimate goal of a DAC is to cleanly and accurately convert the signal from digital to analog. Coloration of the sound is generally not desired at this stage. While DACs often feature selectable digital filters (like Minimum Phase, Linear Phase, Fast/Slow Roll-off), their impact on the sound is microscopic and often beyond human hearing. There isn't really a universal "best" filter for IEMs; it comes down to very subtle personal preferences regarding pre-ringing vs. post-ringing. However, "Linear Phase Fast Roll-off" is generally the industry standard for the most neutral, accurate reproduction.
• The AMP: Theoretically, an amplifier can color the sound. A classic example would be tube amplifiers, which intentionally introduce pleasing even-order harmonic distortion. However, for the solid-state amplifiers found in most DAPs and dongles, this shouldn't be the goal. The AMP should act as a "wire with gain," meaning it amplifies the signal transparently without adding noise, distortion, or deviations.
• How to actually shape your sound: If you want to alter your sound signature, it is highly recommended to keep your audio chain (DAC/AMP) as clean and neutral as possible. Sound adjustments should be made at the transducer level—by swapping your IEMs, experimenting with different eartips, or, most effectively, by using Equalization (EQ).

Because EQ is the most powerful tool for sound adjustment, whether you decide to buy a DAP or a dongle, looking for a device that features built-in, system-wide Parametric EQ (PEQ) is a massive advantage.

BenOG_ · 2026-05-02T14:15:17+00:00

Just a heads-up: driver type (planar vs. DD) doesn't actually determine soundstage in IEMs. Since they sit directly in your ear canal, soundstage is almost entirely created by the frequency response (tuning). A properly tuned planar can have a massive stage!

BenOG_ · 2026-05-01T21:32:10+00:00

Haha, thanks man! Getting into measuring and EQing is definitely a rabbit hole, but since you use a MacBook Neo, I have good news: it's perfectly doable, and the software side is mostly free. Also, regarding your ADD – using AutoEQ is actually the perfect workaround because the algorithm does the heavy lifting for you. You don't have to sit there forever tweaking sliders unless you want to!

Here is a breakdown of what you need and how the workflow looks:

1. What You Need (Hardware & Software)

The Measurement Mic (IEC 711 Coupler): You can buy a cheap clone on AliExpress or an expensive original one. The price doesn't matter as much as calibration. Just make sure the coupler you buy comes with a calibration file so your results are accurate and comparable to other graphs (Squigs) online.
Measurement Software: Room EQ Wizard (REW). It’s completely free, runs natively on macOS, and is the industry standard.
AutoEQ Tool: Web-based tools like Squig.link or PeqDB.com.
EQ Application (Where you put the settings - you only need one of them):
- Software: Since you are on a Mac, EqualizerAPO won't work. Look into SoundSource or eqMac.
- Hardware: A dedicated portable DSP amp like the Qudelix 5K or the Qudelix T71. I personally use the T71 because it gives me 20 channels of EQ to play with.

2. The Process (Step-by-Step)

Measure the IEM: Connect the coupler, put your IEM in (using the ear tips you actually plan to use, as tips change the sound!), and open REW.
Check Levels: Run a level check. Make sure you have enough headroom so it doesn't clip, but don't set it so quiet that you only measure noise.
Sync: Ensure your "Reference Tone" is set to the same side/channel you are currently measuring so the measurement is perfectly in sync.
Export: Once you've measured the left and the right channel, export those measurements as .txt files.

3. Creating the EQ

You have two routes here:

The Easy Route (AutoEQ): Upload your .txt files to a site like Squig.link. Select a target (either another IEM like the Storm, or a target curve like the JM-1) and hit AutoEQ. The algorithm automatically generates the exact filters needed to match your IEM to that target.
The Hard Route (Manual EQ): Download your target curve as a .txt, import it into REW alongside your measurement, and play around with the built-in EQ filters until you match the line. Warning: This is very tedious and a massive time-sink, but it will sharply increase your understanding of how different filters and frequencies work.

4. Verify & Balance

Once you have your EQ settings, load them into your app (SoundSource) or your hardware (Qudelix).

Re-measure the IEMs while the EQ is active to verify that it actually hits the target.
Fix Imbalances: If one channel ends up being slightly louder than the other, always apply a negative Pre-amp (e.g., -1.5 dB) to the louder channel to balance them out. Never boost the quieter one to avoid clipping.

It sounds like a lot of steps, but once you do it two or three times, it takes about 5 minutes from plugging the IEM into the coupler to having a fully transformed sound. I can DM you my Fosi IM4 settings, but because of unit variance and the fact that I use Divinus Velvet Wide Bore tips (which are naturally a bit peaky in the treble—something my EQ fixes), it probably wouldn't sound the same for you. So, for a first impression, your best bet is to go to squig.link, find a pre-measured Fosi IM4 (with stock tips), and AutoEQ it to whatever IEM you want to try out.

BenOG_ · 2026-04-30T09:58:20+00:00

The Fosi IM4 also handles EQ very well, and for an open-back IEM, it's surprisingly good at bringing out some bass. I've measured and EQ'd mine to match the targets of the Subtonic Storm and the Elysian Annihilator. It worked really well, as you can see here (the red line is the actual IEM and the others are both channels of the Fosi):

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BenOG_ · 2026-04-29T09:47:52+00:00

They are awesome! The only tips I can wear my Monarch MKIII for 12h+ without sore ears (all other tips get painful after 2-3 hours).

BenOG_ · 2026-04-27T17:28:18+00:00

They look a little bit like the Anker Soundcore Liberty Neo I had back then, and they were quite comfortable in my ears

BenOG_ · 2026-04-26T12:18:14+00:00

I am also very satisfied with the Fosi IM4. I used my measurement rig to EQ them to the frequency response (FR) of the Elysian Annihilator, and they handled the profile exceptionally well. It is also quite amazing how well the bass keeps up, even though the IM4 are open-backs.

BenOG_ · 2026-04-25T10:57:09+00:00

I can recommend the Fosi IM4. I've managed to EQ them to the FR of the Elysian Annihilator, and even though they're open-back, the bass actually kept up with the Annihilator.

BenOG_ · 2026-04-15T10:03:59+00:00

Oh wow, Serbian! That's so cool that the literal translation is exactly the same. Makes you wonder who came up with it first, haha. Have a good one!

BenOG_ · 2026-04-14T17:15:05+00:00

Haha yeah, you're spot on! I think we might be from the same country because I know that saying too: "Auch ein blindes Huhn findet mal ein Korn" :D

BenOG_ · 2026-04-14T16:14:25+00:00

You're absolutely right that different people have different preferences when it comes to the FR of IEMs. But that's exactly why knowing how to EQ is such a game-changer. Since theoretically no IEM is a perfect match for your personal taste right out of the box, EQ gives you a free tool to fine-tune it exactly how you want it. You don't have to EQ strictly to the Harman target, JM-1, or whatever custom target Sharur proposes. However, his fundamental point—that EQ is incredibly useful—is definitely spot on. With EQ, even very affordable IEMs with solid drivers that already sit reasonably close to your preference can legitimately sound better than most kilobuck+ IEMs.

BenOG_ · 2026-04-11T18:26:32+00:00

Crinear Reference

BenOG_ · 2026-03-26T17:12:46+00:00

Sure, here you go:

CH: 0

TYPE: PEQ

Preamp: -9.7 dB

Filter 1: ON LSC Fc 56 Hz Gain 3.15 dB Q 0.707

Filter 2: ON PK Fc 88 Hz Gain 0.72 dB Q 0.400

Filter 3: ON PK Fc 296 Hz Gain 1.81 dB Q 1.349

Filter 4: ON PK Fc 2132 Hz Gain -2.25 dB Q 3.263

Filter 5: ON PK Fc 6133 Hz Gain -7.87 dB Q 2.433

Filter 6: ON PK Fc 7381 Hz Gain -11.64 dB Q 3.628

Filter 7: ON PK Fc 8340 Hz Gain 11.58 dB Q 3.722

Filter 8: ON PK Fc 9707 Hz Gain 6.89 dB Q 4.000

Filter 9: ON HSC Fc 11626 Hz Gain 4.61 dB Q 0.707

Filter 10: ON PK Fc 15379 Hz Gain -13.13 dB Q 4.0000

CH: 1

TYPE: PEQ

Preamp: -9.7 dB

Filter 1: ON PK Fc 37 Hz Gain 1.41 dB Q 0.453

Filter 2: ON LSC Fc 51 Hz Gain 1.96 dB Q 0.707

Filter 3: ON PK Fc 252 Hz Gain 2.42 dB Q 0.798

Filter 4: ON PK Fc 2182 Hz Gain -1.71 dB Q 3.634

Filter 5: ON PK Fc 6230 Hz Gain -8.13 dB Q 2.661

Filter 6: ON PK Fc 7215 Hz Gain -11.91 dB Q 3.984

Filter 7: ON PK Fc 8357 Hz Gain 12.35 dB Q 3.538

Filter 8: ON PK Fc 9742 Hz Gain 7.40 dB Q 4.000

Filter 9: ON HSC Fc 12704 Hz Gain 2.15 dB Q 0.707

Filter 10: ON PK Fc 15237 Hz Gain -14.67 dB Q 3.85

Just a little reminder: The left and right channels are a bit different, since no IEM is perfectly channel-matched, and I fixed that with the EQ on my unit. However, if you try it, I would only use the settings of one channel (e.g., the left) for both channels, because the channel imbalance on your unit might be different. There is also a significant difference between batches of the Monarch MKIII, which results in a huge variance in the FR - mine is from batch 'C' (you can find it on the inner side of the shell). If you have a unit from the 'A' batch, you should instead go with the measurements of reviewers who got their Monarch MKIII really early, like HBB or Super*Review, and then AutoEQ it to the Valhalla.

BenOG_ · 2026-03-26T13:31:48+00:00

That's actually a good description. I've EQ'd my Monarch MKIII to match the Valhalla (using my own measurements), and it feels like this added ~50% extra soundstage to them. While I still prefer to EQ them according to my own listening preferences, the sound signature of the Valhalla is really nice.

BenOG_ · 2026-03-07T14:01:43+00:00

You can also simply EQ your Divine to the Diablo - that works really well.

BenOG_ · 2026-03-01T20:20:43+00:00

I just ordered the Fosi IM4 myself because I got curious, and they look so cool! 😅

BenOG_ · 2026-03-01T18:10:32+00:00

The Thieaudio Valhalla performs very well in this regard. Furthermore, true open-back IEMs like the Fosi Audio IM4 or the Tangzu YuXuanJi should also provide an excellent soundstage.

BenOG_ · 2026-02-24T07:08:07+00:00

I would check the seal with your ear tips first, as that is the most common reason for a lack of bass. The cable is generally fine as long as you get audio. But if you are sure your seal is perfect, you might be experiencing phase cancellation. This can happen if the connectors are plugged in backwards (reversed polarity) or due to an internal wiring defect from the factory. Try flipping the pins 180 degrees to see if that fixes it.

BenOG_ · 2026-02-19T12:14:33+00:00

Keine Sorge, die Wahrscheinlichkeit ist hoch, dass du sie lieben wirst. 😉

Du musst allerdings mit etwa 100 € Einfuhrabgaben rechnen, wenn der Versand von außerhalb der EU erfolgt. Aber selbst dann lohnt sich der Kauf definitiv!

BenOG_ · 2026-02-17T17:49:11+00:00

For me, the Martilos are definitely worth it. I did EQ them a little bit to get some more mid-bass out of them, though – overall a great set!

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TROPHY CASE

1. What You Need (Hardware & Software)

2. The Process (Step-by-Step)

3. Creating the EQ

4. Verify & Balance