[Simon Linke]

I'm using a MacBook Pro connected to a Fiio E17 via USB and from there to a HeadRoom Micro Amp out to the K550's.
With gain set to 0 on the Fiio and medium on the HeadRoom I have to turn the volume up high on iTunes, the Fiio and the HeadRoom to get a reasonable and engaging sound.
Previously I was using IEM UE10's with the same amp/DAC combo and low to mid volumes produced a loud volume.
I've discovered that turning the gain to high on the HeadRoom makes the volume on the K550's really loud and the music becomes much more alive as opposed to seeming slightly far away and less engaging.
Not really understanding what gain is I've tried to read up about it but have been defeated by the more technical explanations. What I did read was that a 32 ohm headphone doesn't benefit from an amplifier and that using high gain can overpower headphones in this class. Now I'm wondering if I shouldn't be using these amps with the K550's. Does anyone have any advice around this question please?

 

[arcticears]

I do not understand why you are using two amps in series.  You should not need an amp necessarily to drive 32 ohm headphones but the K550's may benefit from one.  Try just using the E17, turn the volume on itunes up to 100% and control the volume with the E17.
 

 

[Can Junkie]

My home tower and sometimes my laptop feed my udac2 which technically has an amp in it. The udac portion of the udac2 does add seperation and clarity to my M50's (32ohm cans) but the amp of the udac2 does not add anything. I therefore let the udac feed my little ramsey SHA-2  amp. The amp has its issues. (a little low level hiss and you have to remember to unplug the cans before you turn the amp off and turn the amp on first then plug the cans in. Otherwise your cans produce a nasty pop) It's a kit I built. Anyway, the amp has volume, bass and treble control knobs and a loudness buttion that makes all the difference in the world. I simply shake my head every time I see a thread saying m50's do not need to be amped. Do m50's and most 32 ohm cans "need" to be amped to use them,....no. Can they benifit tremendously from an amp? Yes,...but..... Guess it all depends on how the amp stamps it's "signature" on the cans. This is true for 32 ohm cans and do not let anyone tell you different. (with the right amp that is) The SHA-2 simply opens up both the top and bottom ends of my M50s. I would not consider not using it despite all its issues.

 

[PurpleAngel]

Quote:

I'm using a MacBook Pro connected to a Fiio E17 via USB and from there to a HeadRoom Micro Amp out to the K550's.
With gain set to 0 on the Fiio and medium on the HeadRoom I have to turn the volume up high on iTunes, the Fiio and the HeadRoom to get a reasonable and engaging sound.
Previously I was using IEM UE10's with the same amp/DAC combo and low to mid volumes produced a loud volume.
I've discovered that turning the gain to high on the HeadRoom makes the volume on the K550's really loud and the music becomes much more alive as opposed to seeming slightly far away and less engaging.
Not really understanding what gain is I've tried to read up about it but have been defeated by the more technical explanations. What I did read was that a 32 ohm headphone doesn't benefit from an amplifier and that using high gain can overpower headphones in this class. Now I'm wondering if I shouldn't be using these amps with the K550's. Does anyone have any advice around this question please?

32-Ohm headphones can benefit from the right kind of headphone amplifier.
Technically with a 32-Ohm headphone, you want a headphone amplifier with a low impedance (4-Ohm or less)
I know the Fiio E17 comes with an impedance of under 4-Ohms, not sure on the Headroom Micro Amp.
How do the AKG K550 sound hooked directly to the E17's headphone amplifier?

 

[Simon Linke]

Thank you all for your replies, I very much appreciate your help. @arcticangel and @purpleangel I took your advice and just connected the Fiio E17 and this has worked very well and I'm really enjoying how it sounds. @arcticangel, I thought having the amps in series was not right but I felt the HeadRoom amp was better than the E17 but the DAC on the E17 was so much better than the 3.5mm headphone connection to the HeadRoom from the MacBook. So I tried using them both not wanting to waste either. Perhaps this was not so sensible. But thank you @Can Junkie for letting me know how you approached what I take to be a similar dilemma, two devices each doing something better than the other one. And thank you for your views on amps with 32ohm phones. I'm not even sure that the HeadRoom is that much better on reflection because I realise I'd been listening to it with gain switched to medium (there is no off) and had took the urgency of the sound to be better. But the highs seem very bright, almost painful, and when I switched the gain to low I wasn't really able to identify such a significant difference on a short listen. Maybe because the HeadRoom cost x3 the cost of the Fiio I wanted to believe there was a difference.
Thanks again for your help.

 

[arcticears]

Glad we could help.  It is never good to feed one amp into another no matter how good they are.  You can get a Fiio L7 dock cable for the E17 that will give you a line out signal.  This will pull the signal from the dac of the E17 and bypass the amp section.  You can feed this to  the headroom amp.  This will allow you to see if the headroom amp is any better than the E17.  One other thing, it should always be best to run an amp at the lowest gain setting that will give you the volume you want.
 

 

[Simon Linke]

Thank you arcticears.
That's a great suggestion using the L7. I'm going to order one today. And thanks for clarifying the question of serial amps and gain vs. volume. I feel I'm sailing in calm waters now!