A set of 3D-printed headphones, alongside a DAC/amp/EQ board powered by a Raspberry Pico. - GitHub - ploopyco/headphones: A set of 3D-printed headphones, alongside a DAC/amp/EQ board powered by a R...
I've got the closed back classics - SRH440, ATH-M50, MDR-V6. Subjective listening tests are not great in my opinion. The Ploopy sound great, but they also sound different due to being open back and the drivers being further apart. Do they sound great because they sound different? I can't tell. Their frequency response does sound accurate overall. I can't tell if there's distortion and how much it is. There was some distortion due to overly amplified input filter gain that I helped them fix a few months back. I can technically put them on my MiniDSP EARS and measure them, but the EARS isn't a great measuring fixture. The idea of sending them to Amir from ASR crossed my mind. 🤭
Good to know there isn't noticeable distortion then. The frequency responses I have seen look good to me. I definitely hope to see some in depth measurements come out for them! I assume some audiophile creators are getting their hands on them, and I would expect to see reviews in the near future.
Here's another bad measurement I did just now on my EARS. Bad because there are known problems with the EARS like the giant hump at 4.5K which is not due to the headphones but a resonance in the "ear canal" of the EARS. The red is SRH440, and the blue is the Ploopy. One of the graphs has psychoacoustic smoothing applied. The other has no smoothing.
There's a hump at 43 which is EQed down and a trough at 420 which is EQed up. They get a lot better in the psychoacoustic view. Again, ignore the gore at 4.5K, that's strictly a measurement problem.
My noise floor is bad so the overall noise level is useless but humps in THD are somewhat useful. Here it is:
There's a small hump around that trough at 420. Nothing ridiculous overall. The gore at 4.5K is again due to the measuring equipment.
So I saw an HE400se on sale and that's supposed to produce pretty great sound with just a couple of PK filters. So I grabbed a pair. Well it's pretty good but there's treble missing that exists in both the SRH440 and Ploopy. It's the kind of treble that is often attenuated in standard EQ presets with a high shelf like this:
I just checked the latest firmware of their DAC and it has a bit of distortion when driven at the default settings. There's now an app that allows to adjust the pre gain to eliminate it but then the final output is not very loud. I think this is the reason why they keep the pre gain as high by default. There isn't a lot of distortion but if you know where to pay attention, you can hear small pops here and there. I'm driving mine with a set of Topping gear. The output is Topping E30 II and that can drive them loud enough without distortion. I've dialed in their default PEQ into PulseEffects's EQ. To be clear, these cans cannot be used without PEQ. That's part of the trick making a physically imprecise driver to sound good. If you want to use alternate DAC/amplification, you have to replicate the PEQ somewhere along the signal chain.
Good to know that it's not to hard to recreate the EQ. I'm already using EasyEffects convolver effect for my current headphones. I was planning to give the included DAC/AMP a try, but I'd definitely prefer to use my own Schiit stack in the long run. Are you able to share the PEQ you are using?