@Don Troubles the LCD-X is really easy to drive. From looking at Amir's review of the Motu Ultralite Mk5 it's not exactly great headphone performance for the price of the thing, there are dongles that do better, but the LCD-X sensitivity is 103 dB/1mW which is super sensitive for an over-ear. Amir measured 77mW on the Motu into 33Ω, presuming it does similar into 20Ω (theoretically, should be more, but some amps have issues with lower impedances) that's 122dB. That's very loud. At 5mW Amir got the best THD+N, at around -93dB. 5mW = 110dB. Still very loud. So to be honest for these specific headphones they could well be just fine.
I'm honestly regularly surprised by how loud these are, even in low gain with volume below the 12 o'clock I plug them in and it's, wow, these are loud.
If you did want to get something else, the likes of the Moondrop Dawn Pro dongle at $50 has more than enough power for them balanced, and a bit more than the Motu (Dawn Pro does around 120mW balanced). It should also have much lower noise and distortion. I mention that one as I have it, and can confirm from trying it, it's more than enough. Fiio's new $29 KA11 claims 245mW, and that's single ended, so you wouldn't even need a new cable. Fiio are generally honest with power claims. I think that might be a good pick and what I'd get if I was looking for a portable solution for it now. But I haven't heard it, while I have the other stuff, so can't say for sure.
You need EQ for the LCD-X, Qudelix 5K is a good option for them and more than enough power-wise. Oratory's profile is a good starting point, I found I had to modify it substantially (I don't on other headphones), possibly as Audeze has absolutely huge batch-to-batch variation, so all you can really say is you have something with the same general shape, it's very unlikely Oratory's sample is particularly close to yours. Subjectively, my ones seem to have quite a bit more upper mids stock so Oratory boosts too much there, makes them very intense and shouty.
My favourite headphones are Hifiman, like HE1000, Arya, followed by Focal Utopia or Clear. All of these are far more forward in that area, so it's not that I'm not used to forward upper mids, I am very used to them and the LCD-X is extremely dark and muffled stock. But Oratory has a HUGE boost in the upper mids, almost 10dB cumulatively at 3.8kHz vs the lower mids. It does need a significant boost, but for me that was too much.
View attachment 353129
I started with his profile and then adjusted that down, taking 2-4dB off between the high shelf and the 3,850Hz peak. So same general shape but just less of that 3,850Hz boost.
View attachment 353125
I actually ended up using most of the time a simpler profile:
Code:
Preamp: -3.5 dB
Filter 1: ON LSC Fc 105 Hz Gain 6.5 dB Q 0.71
Filter 2: ON LSC Fc 300 Hz Gain -3 dB Q 0.71
Filter 3: ON PK Fc 700 Hz Gain -1.5 dB Q 1
Filter 5: ON PK Fc 3800 Hz Gain 3.5 dB Q 1.5
View attachment 353126
I'm using sine sweeps and my ears to try to figure this out, I don't have a measuring rig for over-ears. I do for IEMs, and I have the Audeze Euclid... which confirms typical Audeze variability, these have comical variations, like they can be 6-7dB off. So Audeze, you sort of need to DIY, ideally if you have a rig, I did get the Euclid
just right with that but if not just use your ears and try to figure out what sounds good on your specific sample.
If this was my only headphone, I would go higher on the upper mids boost. But's it's not, and most of my other headphones are tuned with much more there. So with the LCD-X I'm OK with it being a bit darker and more relaxed in the upper mids, like what's the point of having all these headphones if I am going to EQ them all back exactly to Harman.
One of the advantages of this lesser EQ is that it only needs -3.5dB pre-amp vs -9.5dB on Oratory. The LCD-X is very easy to drive so this is much less of an issue than harder to drive headphones but with that sort of pre-amp you are effectively reducing the sensitivity from 103dB/mW to more like 93dB/mW and that is comparable to stuff like Hifiman. If you have a lower power source, could be start to be a limiting factor.