DrSheep
Headphoneus Supremus
- Joined
- Nov 17, 2012
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That's one short interconnect, very cute.
miceblue: those frequency response variations are typical of high output impedance combined with non-flat impedance curve from the IEMs, which is very common with BA IEMs.
To avoid those variations (which distort the audio), you want to plug them into a headphone out with an output impedance that is lower than 1/8th the impedance of the IEMs. With your 32Ω Shures, that would be 32/8=4Ω.
Well, I suppose. But it's always better to hear from users than trust marketing talk. ^^
Actually I have a question for @jseaber regarding amplifier designs. What design challenges are presented when trying to drive earphones with multiple balanced-armature drivers?
I've seen objective measurements done on portable media players with different in-ear earphones and the frequency response almost always turns out differently when driving an earphone with balanced armatures compared to one with dynamic drivers.
Here's one for example:.......
Heh, I am personally responsible for every product specification and description. I wrote the C5 description in 2013 to convey the amplifier's intended usage. Around its Feb 2013 release, a few people assumed C5 would easily drive orthodynamics. The lengthy release article explained that was not a feasible goal for C5, but not everyone takes the time to read my essays. Hey, I understand. Who has time to find and read an engineer's 10 page product report? Anyway, I slightly revised the description after release to be as accurate and as concise at possible. Accurate claims keep people happy. Why disappoint?
@miceblue: skamp is correct. Balanced armatures have particularly wide impedance fluctuations. Low output impedance is critical here. As with other highly efficient drivers, it's also important to minimize Noise.
Interesting. I use my C5D with both the Hifiman 400 and 400i. Now I don't sit and seriously pick apart the sound, this is for "sort of" portable use around the house and yard. The C5D seems to do a quite adequate, if not very good job in that role. Of course, both the 400 and 400i are considered to be relatively easy to drive for planars. If we are talking HE 6, I can see why you would say it may be a no go.
It's unfortunate that when the my c5 is set on max on high gain, the treble distort quite badly.
It clear stuggles to drive my hd25 with a sensitivity of 120dB to high volumes.
Innerfidelity measured the HD25-II to require 0.04 mW of power to reach 90 dB SPL at 74 ohms. The C5 should have absolutely no problem driving that. From here, the C5 outputs about 60 mW of power at 62 ohms.
Why are you setting the volume level to maximum on high gain anyway? Are you purposely trying to make yourself deaf? o.0
Innerfidelity measured the HD25-II to require 0.04 mW of power to reach 90 dB SPL at 74 ohms. The C5 should have absolutely no problem driving that. From here, the C5 outputs about 60 mW of power at 62 ohms.
Why are you setting the volume level to maximum on high gain anyway? Are you purposely trying to make yourself deaf? o.0
No, they are at 600 ohm but the sensitivity is 120 dB which should be very efficient.
On max setting, I find some tracks aren't loud enough particular even in a noise free environment.
It's only about 20% louder than playing directly off my phone.
I guess the c5 doesn't provide a whole lot more voltage than most standard daps.
That is very strange.
The C5 drives my 669-ohm AKG K240 Monitor just fine even with DR18 music, and the K240 M is rated at 88 dB/mW of power. I think it's pretty much impossible to have a headphone with a sensitivity value of 120 db/mW as even in-ear earphones don't accomplish that to my knowledge. I certainly have PLENTY of volume left to spare on the C5 with the iPhone line out (as in I get plenty of volume at volume level 11/63 with low gain) compared to straight out of my iPhone, which basically runs at >50% volume.
What's your source/DAC? Maybe it doesn't produce enough voltage for the C5 to amplify.