With the ODAC, a high gain is interesting too when you're applying digital attenuation, like with Replaygain and a subtractive EQ, or simply when using digital volume control. You can easily "lose" 6-12 dB that way, which you might need with power hungry headphones.

Quote:

skamp said:

With the ODAC, a high gain is interesting too when you're applying digital attenuation, like with Replaygain and a subtractive EQ, or simply when using digital volume control. You can easily "lose" 6-12 dB that way, which you might need with power hungry headphones.

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A poorly-implemented digital or analog volume control may distort the sound. This is completely independent of the ODAC.

How is this related to that? I don't know what you mean.

Anyone here tried it with the Beyer dt990 600ohm to specific?

Hey Random,i did purchase a pair of normal batteries and the amp is working with no problem,and i did change the adapter which now has a different plug size,and connected right away with the O2 and it's rechargeable batteries still working strong,Thank you for the responsive advise!!
see ya all
Antonio

Quote:

skamp said:

Quote:

miceblue said:

does the DAC really make a difference in sound quality? I only have 1 dedicated DAC (ODAC) and it doesn't sound significantly better than my on-board computer DAC to me. The amp certainly makes a much larger difference to my ears.

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Indeed, onboard DACs are often able to deliver fine 16 bit performance these days. The main problem is the high output impedance of the headphone out (my laptop measures at 74Ω), which can be fixed with a decent headphone amplifier such as the O2.

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Oh yeah the output impedance could be a problem. Apparently my computer's output impedance is around 24 ohms.
 
 
Quote:

skamp said:

Quote:

miceblue said:

iPods tend to have a high output impedance (something like ~7 ohms)

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5.5Ω (iPod Classic) and less (the latest iPod Touch was measured at 0.75Ω).
Quote:

miceblue said:

I don't know what happens when the output/source impedance ratio is less than 8)?

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Poor/inexistant damping, and possibly frequency response variations if the headphones' impedance varies with certain frequencies.

Sansa Clip+ (0.5Ω) with Ultimate Ears Triple-Fi 10:



iPod Classic (5.5Ω) with Ultimate Ears Triple-Fi 10:



Hifiman HM602 (11.4Ω) with Ultimate Ears Triple-Fi 10:

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Woah jeeze that HiFiMAN output looks pretty scary with those IEMs. I'm guessing the Triple-Fi's multiple drivers and odd impedance response is partly responsible for that curve?
I read from Voldemort's blog of the Clip+ vs iPod Touch 3G that the Clip+ has an output impedance of 1.02 ohms at 1 kHz, whereas the Touch was measured as 7 ohms.

Quote:

antberg said:

Hey Random,i did purchase a pair of normal batteries and the amp is working with no problem,and i did change the adapter which now has a different plug size,and connected right away with the O2 and it's rechargeable batteries still working strong,Thank you for the responsive advise!!
see ya all
Antonio

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Glad it all works fine, come back with impressions when you can

miceblue said:

I'm guessing the Triple-Fi's multiple drivers and odd impedance response is partly responsible for that curve?

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Yes, it's the combination of a high output impedance and a non-flat impedance curve on the IEMs.

Well,i guess i can now share some fun (i hope) thoughts within this thread,now that everything ,or almost,is working.
 
Like i sad before,i have been waiting something to drive properly my HD650 since September,i were more prone to listen some Rock'nRoll from my Clip Zip via HF5 rather then plug my Sennheiser directly to my old Samsung laptop..
It has been a little bit an endurance of waiting because i wanted as much as soon to have some good sounding listening session for myself,deserved,and i have never been a person with the virtue of patience,sadly for me,more the contrary,a hyperactive and nervous cook who like to listen from Metal to Bossa Nova,from Jazz to Symphonies.
 
A chronological marathon in trying to achieve my health trough the gym,going every sacred morning Monday to Saturday ,unwilling to put more weight to lift up.Then go back home to a quotidian dish made of unsalted and un-fatted chicken and sweet potato.It is a miracle i have now been on this routine since October,and honestly sometime i feel i start to grow feathers and clucking.
But i can't deny i feel the positive results ,paradoxically even that i am taking this seriously i can work better and with more stamina everynight.
A Sunday off work with some great traditional barbecue accompanied with a German Weiss bier is more than welcome,more then ever,haha!!
 

 
Not that surprising i did had more time to listen to music on my oldye and very noisy hometown buses going and returning from work then on my computer;i have never been a long number poster on Head-Fi,and now even less.
 
And right now i am taking advantage of my own coincidental short free time,because of what has been happening in the last few days:

Well to start today i have been to the hospital having a liver biopsy operation routine due to my chronic pancreatic pathology (Which now is completely regular- lousy dried sponge between my stomach and spinal cord..would say Homer), so i knew i would have a day off from work because i knew,even if this is the first time,the doctor told me i could not make any physical effort -Bye work and gym,mhuahah..-and consequently some extra time to listen to AC\CD,Nile,and well,even some Jazz At The Pawnshop.Some affordable strippers maybe next week...
 
But yesterday ,when cleaning the grill at work some dust split off right on my left eye,and quickly i realized i had suffered an injury because i was seeing quite unfocused ,even with my glasses on.So today early before the biopsy i have been on my town public opthamologist to some advise ,so i did spent from 8.30 to 12.30 to having the relieved news that i just need some optical pomade for about 10 days and my left eye vision would restore to normal (I hope,at least).Then i have been from 13.00 to 18.00 for the biopsy and one more hour to come back home feeling like shiit with a bandage on the eye and another on the right back side.So another misfortune:
 
I had to hurt myself on the eye right now that i received my long projected collection of professional and casuals cookbook!
 

 

I guess you can never had it all in just one time,eh?At least my palate still enough sensible...
 
So right now what just left me is a few hours to listen to some tracks and testing my new rig capabilities.That's some awful photo to you to see how asparagus rubber feet can put firmly together  an amplifier,a DAC and their much confused cable very bad managed.
 
 

 
 

 
 
So ,now that i have been listening to Vader-Welcome To The Morbid Reich,AC\DC-Highway To Hell,and Daft Punk-Human After All,i can see,even in those little physical conditions ,and considering i have some kind of Lead Ears ,that differences between with and without additional related audio devices are (Very ,sometimes) noticeable ,but i guess i have to gain some more hours of experiences with this technological mass produced devices to affirm for sure i can define where quantity and the quality of those achievement sound wise.
 
One thing for sure i know,after some day-to-day adventures and coincidental obstacles ,stress testing situation and running fast time living,my ears now are happier then ever ,Angus Young
is a demon ,always get my hearing possessed through Rock'N'Roll.
 
Sorry guys to derail the thread enormously ,especially to the thread started!!  and Happy O2-Odac to everyone.
Best
One-eyed Antonio

That's one hell of a story, enjoy your listening time while you can, and get better soon mate as melhoras

That's one hell of a story, enjoy your listening time while you can, and get better soon mate as melhoras

That's one hell of a story, enjoy your listening time while you can, and get better soon mate as melhoras

Randomkid is in fact a vinyl record...with some groove.

hahaha  lol.

Quote originally Posted by lorriman /img/forum/go_quote.gif

Randomkid is in fact a vinyl record...with some groove.

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Dodgy internet connection, although the groove may be real