As I saw this, I had to respond, so that people do not take erroneous information as fact..../QUOTE]
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and
@DavidA I noticed your reply a while back, haven't had time to respond, I just get these e-mail notifications which I skim through, had a horrible year and the situation ain't over yet, I'll PM you when things settle down.[
As 400i has the same efficiency as 4XX?)
---- For some reason the 4xx with the Focus pads requires more volume in MY case compared to my 400i with aftermarket pads, it could be the ears being closer to the drivers with one set of pads vs another. It's the first thing I noticed when I got the 4xx after I had the 400i for months.
the Grace m9xx doesn't run out of steam with the 400i, even when factoring various listening levels people have, period.
---- I feel that I could use a bit more power when I want to play at higher volume with the 4xx and Focus pads for my taste with the 400i, not so much as those seem to play adequately, though I might run as high as 90 on the 100 scale. I find myself switching to my Audio GD NFB-12 just to get a bit more power and I feel that it has a bit more control when tracks get complicated at higher volumes. For casual listening at normal volumes, I can use either the Grace or the Audio GD with my Hifimans.
Full volume doesn't blow out the driver, but indeed is enough to cause damage to your hearing with continued listening.
This begs me to ask a question, is your source volume to the max (O/S volume/software player volume, and by max I mean just a notch under the max due to inter-sample peaks/clipping, if you're that paranoid
)
---- On my Mac Pro, the system Volume when running the Grace m9xx already set to max by the OS, so I can't adjust it via software settings, basically the m9xx takes over and I can only adjust the gain via the knob. On the Audio GD, I can change volume settings via volume control. I'm not using additional software to boost the volume. As of note, not all of my music is recorded at the same levels and with a couple thousand songs on my library, I have not normalized the volumes. I also notice this with youtube content. Sometimes I wish for a bit more volume.
I sat at 50-75 of the volume on the Grace unit, and that's with a -6dB attenuation from EQ:ing, and pushing over 75 would require a tremendously high dynamic range/low volume content; or to be drunk and show off the combo to a friend for quick test.
Additionally, it's been reported over and over again how extraordinary pairing the m9xx and 400i are, over the years in this thread.
---- It might be a personal preference thing, but I get more dynamics through my Audio GD than the m9xx with the HifiMans. I do however prefer the m9xx with my AudioQuest NightOwls, they seem to have better synergy. The m9xx also seems to run my Audeze LCD2 just fine, but for some reason in my case, not as good with the HE400i / HE4xx. I probably also play music a bit on the louder side, but not to the point my ears hurt or ring after long sessions.
I like both of my Hifiman headphones and might even get the HE-500 later on. I also like the Grace m9xx, but it might be a case that the Audio GD just has more control with planar magentics. I also prefer the m9xx with my Grados and my IEMs. So I don't hate on my m9xx, I'm just saying that I wish it has just a tad more power and perhaps someone else might run into playing headphones at loud levels, which I do at times and wish for a bit more power.