The Sennheiser IE series fit differently from most IEMs. There are two grooves on the stem that hold the eartips. One is right next to the earbud, the other is a few millimeters up the stem. (It's shown on the front page of the booklet.) Be sure you try multiple eartips in both positions...

https://www.amazon.com/Sennheiser-IE-300-Audiophile-Headphones/dp/B08QDNX7S1 Free returns. Check the conditions.

All the Sennheiser IEMs have a small shape, from IE200 to IE900.

Good luck with that.

For a stopgap while you look for high end IEMs, you could do worse than the Sony MH750, which are the size of a fingernail and only cost $15. They're cheapies: hardwired with a short, thin cord that's asymmetrical to go behind your neck, Japanese-style. You might want to add an extension...

Final Type E were too small for me. The BGVP W01 were the only ones that made the Zero 2 fit...almost. I see that Penon Liqueur L are 14mm and XL are 15.5mm... that's promising.

After recently being flummoxed trying to get a fit on 7hz Zero 2 IEMs, I'm wondering if anyone has found good eartips wider than 13mm, the typical L size. Silicone or foam, preferably not ridiculously expensive. 14mm? 15mm? Bring 'em on. Links appreciated.

I just noticed that my (free) Onkyo HF Player app for Android has an 11-band EQ.

You'll get far more audible improvement by upgrading the headphones than by upgrading the source. The R9 seems to be around $1500--you could get some spectacular headphones with that budget.

I just looked at Ali again. If you put your cursor on the store name, ratings pop up -- and also when the store was opened. Choose a store that's been around for awhile that has ratings very near 5.0. No one's going to get a perfect score, but it's harder to gimmick the ratings on longtime...

I've gotten a lot of IEMs from AliExpress with no problems. The only counterfeit one was a Sony MH755 -- but it was $5 and they are widely known to be counterfeited, so I should have known better. Counterfeits tend to be big-name brands, to make it worth the trouble. Yanyin is pretty niche so...

Alas, I'm in the minority that can't get a good fit on the much-praised 7Hz Zero 2. Arrived today, tried all my eartips, no seal. They are definitely working, though. So here they are at just half the Ali price, shipped to USA. In the original box and outer sleeve, just unwrapped today, with...

Unfortunately that has been my experience. Dozens of tips -- foam, silicone, double-flange, triple-flange, bullet-shaped, igloo-shaped, conical -- and I can only get a good seal in one ear. I usually have to do a little tip-rolling and I have years of assorted tips, but this is the very first...

After reading all the hype here about the Zero:2, I got a pair when they dropped under $20 -- my first budget hype train in a while. Turns out they are not for everybody. For me it seems that the short nozzle makes it almost impossible to get a good seal -- and I tried dozens of tips: silicone...

What are your priorities? Comfort, dialogue clarity, action-film rumble, spatial effects? Do you need closed back for isolation? Also, what's your prospective budget?