Nazo
100+ Head-Fier
- Joined
- Aug 24, 2008
- Posts
- 190
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- 11
I'm not sure if this is the best place to ask, but here goes. I just got an HD650 hoping its sound signature would be more like what I got from the HD555 I modified the heck out of but with the higher quality, lower distortion, etc etc of a higher end headphone. After looking at a lot of things (particularly sound response curves on HeadRoom) it seemed like the HD650 might be about the right balance of things for me with a response curve not so terribly different from the HD555. I guess I was wrong. To me it really did end up feeling like it really does have the so called "Sennheiser veil" which I never took seriously before with that modified HD555 (mind you, I never heard the HD555 stock. I got it on sale for $80 on a whim and without even thinking seriously about it did the soundstage mod before it was even burned in without listening. I never imagined I'd become a Sennheiser convert after it was fully burned in, but I definitely did.) I have a pretty decent (if perhaps not the best of the best, still good) setup with a Fiio D3 acting as an external DAC (using optical output from my soundcard, so I still get the benefits of a soundcard that plays well with games and such and less CPU usage while having an external DAC essentially) feeding directly to a CmoyBB 2 (with the bass boost turned off... Yuck.) The CmoyBB 2 is being fed by a very good lithium ion battery (probably around 2800mAh for the usable range I'd guesstimate) running through a DC-DC converter. I'm sure this isn't ideal, but any noise it may produce is well beyond my hearing capabilities and frankly it sounds almost completely silent even if I turn it all the way up to me (plus my custom case enclosing all this together is kind of a hodge-podge mess right now.) I'm not an expert on these things, but the noise I think is supposed to be in the really really high frequency ranges (I think MHz even?) so probably gets pretty easily and thoroughly filtered out in audio equipment. Oh, and the D3 is powered directly by lithium ion (no converter needed it seems. I guess it works down to around 3.3V or something in that sort of range and it doesn't use a lot of power, so I just stuck in a thin li-po that just barely fit and I'd personally swear it gets rid of all the problems of powering it via USB while lasting a surprisingly long time. For reasons I don't understand with my clearly insufficient electronics knowledge it did not work when I tried to use the same battery going to both the DC-DC converter and the D3 in parallel -- I'm sure it's something blatantly obvious and silly to those with more knowledge of such things than myself.) Anyway, one advantage of that DC-DC converter is basically any voltage within from about 4.6 or so on up to 35V or so is possible. I was using 12V which seemed to be just fine, but I went ahead and upped it to 18V a bit ago. It didn't seem to really help though.
Anyway, background aside, I was using an AD8620 which to me seemed to really make that amp sound amazing with the HD555. To me it made both the HD555 and the CMoyBB each sound like far more expensive equipment than they really were. Somehow it just doesn't work with the HD650 -- at least not for me. It sound a bit more dull and lifeless. Even after I upped the voltage it still just didn't really have the enjoyment factor that the HD555 had. Well, the CMoyBB 2 came with a JRC 4556AD OPAMP that I didn't really use originally, so I popped it back in there. Much much better. Still, it feels a bit harsh or something with maybe too much bass and definitely too much in the highs I think. I'm not audiophile or analytical enough to put it exactly into words. It really helps a lot though. It's kind of odd that the AD8620 seemed so much more lively with the HD555...
So I'm kind of wondering: what sort of OPAMP should I be considering for the HD650? Maybe something a bit more in between those two sound-wise? Particularly it would be nice for something with a bit of warmth to the mids, but I guess I want mostly neutral-ish highs and lows (I happen to love bass, but I want it to be relatively flat, low distortion, and accurate, not pounding my skull. That's one of the things I really loved about those HD555s as they could go quite low without distortion but weren't so fatiguing or recessing other ranges to emphasize the bass like so many things do these days.) Also, highs are a bit tricky with me. My ears are pretty sensitive to certain frequencies (I assume related to hearing damage from my speaker times as I do have some Tinnitus even) and anything sparkly often outright physically hurts (one of the reasons I've been finding myself leaning so much towards the Sennheiser sound.) So mostly neutral or perhaps even a very slight recess across the lows and highs with maybe a bit of warmth in the highs is probably the sort of thing I'm looking for.
Yeah, I know I should probably be using a higher end amp, but at this point it has become pretty integrated into my setup (plus I kind of blew all my money on the HD650 thinking it would still sound as amazing with that CMoy + AD8620 setup without any need to change the amp.)
EDIT: I did a lot of searching around and found one person talking about a few OPAMPs for the CMoy. I rather liked the description of the OPA2228, so I ordered one and am currently giving it a shot. More testing is needed, but it does already sound like it might just be the sort of thing I'm looking for here.
Anyway, background aside, I was using an AD8620 which to me seemed to really make that amp sound amazing with the HD555. To me it made both the HD555 and the CMoyBB each sound like far more expensive equipment than they really were. Somehow it just doesn't work with the HD650 -- at least not for me. It sound a bit more dull and lifeless. Even after I upped the voltage it still just didn't really have the enjoyment factor that the HD555 had. Well, the CMoyBB 2 came with a JRC 4556AD OPAMP that I didn't really use originally, so I popped it back in there. Much much better. Still, it feels a bit harsh or something with maybe too much bass and definitely too much in the highs I think. I'm not audiophile or analytical enough to put it exactly into words. It really helps a lot though. It's kind of odd that the AD8620 seemed so much more lively with the HD555...
So I'm kind of wondering: what sort of OPAMP should I be considering for the HD650? Maybe something a bit more in between those two sound-wise? Particularly it would be nice for something with a bit of warmth to the mids, but I guess I want mostly neutral-ish highs and lows (I happen to love bass, but I want it to be relatively flat, low distortion, and accurate, not pounding my skull. That's one of the things I really loved about those HD555s as they could go quite low without distortion but weren't so fatiguing or recessing other ranges to emphasize the bass like so many things do these days.) Also, highs are a bit tricky with me. My ears are pretty sensitive to certain frequencies (I assume related to hearing damage from my speaker times as I do have some Tinnitus even) and anything sparkly often outright physically hurts (one of the reasons I've been finding myself leaning so much towards the Sennheiser sound.) So mostly neutral or perhaps even a very slight recess across the lows and highs with maybe a bit of warmth in the highs is probably the sort of thing I'm looking for.
Yeah, I know I should probably be using a higher end amp, but at this point it has become pretty integrated into my setup (plus I kind of blew all my money on the HD650 thinking it would still sound as amazing with that CMoy + AD8620 setup without any need to change the amp.)
EDIT: I did a lot of searching around and found one person talking about a few OPAMPs for the CMoy. I rather liked the description of the OPA2228, so I ordered one and am currently giving it a shot. More testing is needed, but it does already sound like it might just be the sort of thing I'm looking for here.
