[mikeaj]

Quote:

Comparison "with" and "without"O2 when listening to K550.

 
I don't mean any offense at all, but right now I seriously can't figure out whether to blame myself or you for wasting both of our times, even if it's just a couple minutes.  

 
Without the amp, you would be plugging the headphones into what?  An amp isn't like an effects processor, EQ, or something like that.  To get sound out of headphones, you're running them out of some type of device.  To gauge the performance of another amp (here, the O2) relative to that, you need to know the characteristics of the original device, how good or bad it is (and in what ways) it is for driving headphones like that.

 

[placebo-fi]

K550 has pretty awful distortion in the bass so not sure if anything can fix that? Google "K550 measurements". I do not have any experience with these cans by the way, just talking from observation.

 

[cyberalpha11]

I don't mean any offense at all, but right now I seriously can't figure out whether to blame myself or you for wasting both of our times, even if it's just a couple minutes.  :mad:

Without the amp, you would be plugging the headphones into what?  An amp isn't like an effects processor, EQ, or something like that.  To get sound out of headphones, you're running them out of some type of device.  To gauge the performance of another amp (here, the O2) relative to that, you need to know the characteristics of the original device, how good or bad it is (and in what ways) it is for driving headphones like that.

Sorry for not putting my statement clear. Basically the comparison is as below:

CASE 1: ipod classic + k550 (no amp, no ext. DAC)
CASE 2: ipod classic + k550 + O2 (no ext. DAC)

Even though k550 is easy to drive headphone, but I found the bass is a bit soft.
By adding this O2 in the equation, will it further enhanxe the sound quality especially the bass.
This is what I would like to find out.

 

[adydula]

the audio out that u plug your cans in the apple device has been converted from digital and amp in it.
 
Adding another external amp like the O2 etc may make things worse depending on the quality of the audio out of the device.
This is like amplifying the stuff twice...
 
Most of us take the digital bits out to a external dac, then amp for the best possible conversion and amplification.
 
Alex

 

[stv014]

Amplifying the headphone output of an iPod (and many other devices) with the O2 can easily improve the overall performance, as the O2 itself degrades the audio signal only by a small (normally not even audible) amount, and it can drive headphones better than the iPod. Basically, what you gain by the iPod having to drive only the input of the O2 (which is an easy load compared to a headphone) is greater than what you lose by having the O2 in the signal path. However, using the O2 on an already very good headphone output might not make any useful difference.

 

[adydula]

It wont improve the overall performance, it will just amplify the signal....if thats what you mean about improving "overall" perfromance then i agree....but overall usually implies more that just amplification.
 
If the source is a stellar signal, then it comes out amplified wonderfully....with no audible additions or subtractions...if the souce is less than stellar, the sound out will be just than that...less than stellar...
 
I am starting my third 02 DIY....this is a great little device.
 
Alex

 

[mikeaj]

Read again what stv014 wrote.
 
The key point is that the signal the iPod "sends" depends on what it's sending to (even with all the same settings, configuration; this is a matter of hardware performance).  If it's connected to one headphone, the signal will be different than if it is connected to a different headphone, which will be different than if it is connected to an amp—the amount of imperfections manifested depends on the load.  When connected to an amp, the imperfections will be smaller.
 
This isn't so much true for an iPod, but many devices (those not intended for headphones) will sound terrible with headphones but will sound just fine connected to an amp.

 

[adydula]

combine that with double amplicaction and it can make things even worse....
 
Alex

 

[mikeaj]

Quote:

combine that with double amplicaction and it can make things even worse....
 
Alex

 
Double amping was already considered.  And for what it's worth, there really shouldn't be too much distinction between having a preamp and power amp (double amping?), multiple stages in one amp (which almost all do unless you're talking about a CMoy), multiple amps strung together, and so on.
 
As a quick and dirty example, RMAA IMD test results:
 

 
Test is 60 Hz tone and 7000 Hz tone together, so everything else is bad (higher is worse, aside from at 60 Hz and 7000 Hz).  White line is single amped.  Green line is double amped, where the second amp is better than the first amp.

 

[sling5s]

O2 with dacport or O2 with Odac for Lcd-2 and grado magnums?

 

[sling5s]

How would the Dacport as amp/dac combo compare to O2+ODAC

 

[mikeaj]

Quote:

How would the Dacport as amp/dac combo compare to O2+ODAC

 
O2 is more powerful, which is a statement about output power levels and not any impression about sound quality.  Aside from that, different people are going to have different opinions.  Personally, I'd rather have something all in one and not as clunky as O2+ODAC.
 
If you listen to very quietly-mastered classical / jazz recordings at a loud listening volume, DACPort is not quite going to be powerful enough for the LCD-2 (maybe; if it's the Rev2, at least according to Tyll's measurements at InnerFidelity, are a little quieter).  i.e. it will not get loud enough.  Sound should still be fine.  Leckerton Audio UHA-6S-MKII, if you have a S/PDIF source or just go with 16/48 max, has similar output levels—actually, a little less into lower impedances and a little more into higher impedances.  I mean, there's a certain power limitation if you're running off of USB.

 

[adydula]

I have one ODAC in a seperate enclosure that I can insert into my high end 2 ch setup so I can compare the dac with other dacs....works well.
 
I have an integrated O2amp and ODAC in one enclosure for just cans listening that I can move around easlily....to one of my five desktop pcs, notebooks, tablets etc...
 
The integrated solution is still less than $300....just in this solution no batteries....but this can be done in a larger case...
 
Alex

 

[themoddingden]

wood aww man .
do you make them?

 

[sling5s]

Placed order for O2+ODAC combo.  With so much hype on both I'm kind of excited but I fear I will be underwhelmed.
Why? Well I'm kind of on the "warm, musical, and colored" camp.  That's just my preference.  Can't help it. 
But I'm hoping I'm pleasantly surprised.