IM4

Fosi IM4 should be everyone's sub-$100 pick.

The Septet is really disappointing, not because it's bad, but because my $85 Fosi IM4 does the same thing for much cheaper.

I'm listening to my first song on these as I type this (Ring of Past by Men I trust) and I'm pretty impressed! I like the detail up top and, like you said, the punch of the bass isn't as soft as I expected. I probably will mess around with long light EQ on my Protocol Max just to see how it goes, but overall I'm pretty happy for the price. Then again, I'm one song in haha

For me, out of all IEMs I have tried so far, KZ ZEX Pro, KZ DQ6 and Fosi IM4, all with those internal bumps in the higher part of the IEM, close to the cable.

I just picked up a set of the IM4s and am quite surprised at their sound for the $ I paid. I’m running it though my ZH3 as well, and for my old ears is fantastic. How do you find the KA11? I’m looking for something on the go as well.

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): https://preview.redd.it/11qs86ovpayg1.jpeg?width=1524&format=pjpg&auto=webp&s=176ce9b6a8d92d3d2b68e3a409f61bf350e250c4

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**](http://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) 1. **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. 2. **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. 3. **Sync:** Ensure your "Reference Tone" is set to the same side/channel you are currently measuring so the measurement is perfectly in sync. 4. **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](http://squig.link), find a pre-measured Fosi IM4 (with stock tips), and AutoEQ it to whatever IEM you want to try out.

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.