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O2 AMP + ODAC - Page 107

post #1591 of 3396
How does the odac stand up to the bifrost any hear both
post #1592 of 3396

Just finished up my first O2/Odac combo and thought I would share. I'll post pics with the Odac tomorrow when I have a chance. I'm going to be dimming the led soon, that is for sure, lol.

 

 

 

post #1593 of 3396

Looks like... a blue LED?

 

In case you missed it, the voltage drop across the LED on the O2 part is used as a reference for the power management circuit. If you swap the color and thus get something with a different forward voltage drop, funny things could happen like things not turning on. But if it works, no problem.

post #1594 of 3396

Hi Guys,

 

I'm getting a Beyer DT770 250 ohm soon, and planning to get JDS Labs O2 amp for it. But I'm wondering if its worthy to get the ODAC too.

 

I've never used a DAC before, and I'm not sure if the ODAC will make much difference to what I'll be listening.

 

I usually listen to FLAC from my laptop or my portable player (iRiver H320)

 

Please advise.

 

Thanks!

post #1595 of 3396
Quote:

Originally Posted by deejay220989 View Post

 

I've never used a DAC before, and I'm not sure if the ODAC will make much difference to what I'll be listening.

 

I usually listen to FLAC from my laptop or my portable player (iRiver H320)

 

That unfortunately does not really tell much, laptops and portable players have quite variable sound quality, about which often little to no reliable information is available. In terms of measured performance, the ODAC is very likely to be an improvement, but if you are lucky with the laptop/DAP, it might still sound good enough (that is, not noticeably different from the ODAC, other than volume) anyway. But it could also be audibly noisy, or have some other problems.


Edited by stv014 - 8/7/13 at 6:14am
post #1596 of 3396
Quote:
Originally Posted by mikeaj View Post

Looks like... a blue LED?

In case you missed it, the voltage drop across the LED on the O2 part is used as a reference for the power management circuit. If you swap the color and thus get something with a different forward voltage drop, funny things could happen like things not turning on. But if it works, no problem.

It is actually a white led. I changed the stock led out for a 1.8v diode, then hooked into the 12v rail for the white led with a resistor inline. I'll probably change the resistor today or tomorrow so you can see the white a little better, lol.

-Erik
post #1597 of 3396
Quote:
Originally Posted by conheo View Post

Can i use the headphone out of O2 (as gain 1x) as a preamp ? Cause the output of ODAC feed my other headphone amplifier is too loud for my sensitive headphone (like AD v.v...). So im willing to use it as preamp but not sure if it will ok ?

 
Yup! I use it as a preamp for my speaker amp all the time, because the output of the ODAC is too high for it too. However, why not just plug your headphones into the O2?
post #1598 of 3396
Figure this is probably the best place to ask this.



So I got an Odac in the mail today, Already owned the O2amp.

Threw them all in the same case / etc. Hooked it up to my PC and everything works great, Sound is amazing.

But whenever i try to change the Bit depth to 24bit, It just doesnt work.

If i hit "Test" on windows, it says "Failed to play test tone"
If i hit apply on 24bit, I get absolutely no sound.


I've tried different Usb slots, Different usb cables, Restarting


No clue why 24bit will not work.


Any idea guys?
post #1599 of 3396

So, I just got to know about Schiit's Magni/Modi. Anyone tried them with DT770?

Magni/Modi or O2/ODAC? 

post #1600 of 3396
Quote:
Originally Posted by Rikuo View Post

Figure this is probably the best place to ask this.



So I got an Odac in the mail today, Already owned the O2amp.

Threw them all in the same case / etc. Hooked it up to my PC and everything works great, Sound is amazing.

But whenever i try to change the Bit depth to 24bit, It just doesnt work.

If i hit "Test" on windows, it says "Failed to play test tone"
If i hit apply on 24bit, I get absolutely no sound.


I've tried different Usb slots, Different usb cables, Restarting


No clue why 24bit will not work.


Any idea guys?


Sampling Rate - what is that set to? The max for the ODAC would be 96 khz. Also, make sure that you have the ODAC selected when making the adjustment.

post #1601 of 3396

amidst the chaos of purchasing the amp/dac i made the rookie mistake of not being sure of the connections, i just assumed the o2 had rca connections on it as it seemed most amps did and so i got the odac with rca to connect but upon receiving both i come to find out the o2 doesn't have rca.

 

doh!

 

now i have to wait to ship out a proper cable so i can start listening, what type of cable would be better to go with? thanks in advance

 

there's a "fiio l2 3.5 to 3.5 cable" or there's a "mediabridge 3.5 to rca cable" around the same price.

 

would there be any difference in going straight from 3.5-->3.5 vs 3.5--->rca ??

 

oh and would i be able to plug headphones directly into the odac plugged into the computer through usb and listen to music while waiting for my new cable? or is that a big no go, do not enter area.


Edited by Nowhere - 8/9/13 at 6:07pm
post #1602 of 3396

There have been a lot of questions around here about the o2 vs magni so here are my impressions of the two. Excuse the awkward transition into the article as it was written for my blog which can be found here http://musicandlistening.wordpress.com/

 

So apparently I was lying a while back when on an audio subreddit, I said that I wouldn’t do a blind abx test. To provide a bit of context, a friend of mine purchased a Schiit Magni, so we decided to compare it to the o2 since one of the things that we’ve seen around some audio sites a lot is the idea that all “transparent” gear should sound the same or at least in a blind abx test. The results were interesting.

 

As far as our method goes, we decided to make all parts of the setup identical (same set of Denon D2000 headphones, cables, and ODAC) except the Magni and O2. Then we started abx testing in two methods. For both methods, we took 30 seconds of listening in which we knew which amp we were listening to based on verbal confirmation (before this we had only spent about 15 minutes on each other’s amps). After that, we started blind testing and left the song playing pulling out the headphone cable between each declaration of an answer until 10 answers were recorded. For the first test, after each pull out of the cable at which either a change or no change could occur, we had to name which was the Magni and which was the O2 based on the 30 second preview that we had. Both of us got between 4 and 6 correct in each of our 3 sets of 10 trials. For the second method (fourth set of 10 trials), we simply had to declare if the amplifier switched. I scored a 9 out of 10 correct and my friend scored a 4 out of 10 correct.

 

I’m sure you’re saying at this point that because the results of the blind abx were inconclusive, that there is no sonic difference. That’s not the case though. During most of the trials, we both had moments in which we knew (and usually exclaimed it out loud in the form of expletives) that we had screwed up which was which and the data showed it in that once the switch got made in our mind, we guessed correctly that there was a change, but got confused on which was the O2 and which was the Magni. The other thing that we noticed was what exactly we were listening for was different — after we finished abxing we debriefed as far as what in the tracks we were listening to for the giveaways of which was which. For a certain track, one of us would say vocals and the other bass kick or one of us guitars and the other piano. Upon re-listening to the track without commenting on which differences we heard, we were able to understand where we had gone wrong. On some tracks there was no difference between the vocal presentation, but there was in the bass and vice-versa. The other problem that we noticed with abxing is the mental pressure aspect. The idea that there could be no change (and the subsequent desire to not look like an idiot by getting it wrong) created a scenario in which the test was not necessarily about what was being heard — it was about the game being played. I had many times in the test where I detected a change or no change — and then the second guessing started. Would he really put a no change there? Would he really switch? Once the doubt in what you heard becomes apparent, the awfulness of auditory memory shows up and you begin to invent differences all in the name of not of the inherent desire to not want to look as if your ears are inferior in terms of detecting differences. It’s equivalent to taking a scantron test and noticing that every single correct answer is A except you aren’t detecting differences on something reliable like knowing a fact. We found that with sighted listening, since the mental game was out of the equation, we were better able to focus on differences in general sound signature and individual details at the same time instead of attempting to focus on mind games and sound at the same time.

 

So without further hesitation, here’s what we heard during our abx trials and sighted listening. Keep in mind that these are generic impressions based on listening to both amps on the same track set of tracks and that these impressions might not apply for every single track that one listens to.

 

1) The O2 has a much cleaner presentation as far as detail retrieval

 

2) On certain songs, the Magni suffered as far as sub bass. It was almost non-existent on some tracks and on others it appeared as a fuzzy fwump noise while the O2 delivered a precise thump

 

3) The Magni’s vocals almost have a veiled warm and thick quality while the O2s were somewhat brighter

 

4) The O2 has more sparkle on instruments such as guitars and piano

 

5) The O2 has a better soundstage as far as width and better placement of things within the soundstage

post #1603 of 3396
Quote:
Originally Posted by Nowhere View Post

amidst the chaos of purchasing the amp/dac i made the rookie mistake of not being sure of the connections, i just assumed the o2 had rca connections on it as it seemed most amps did and so i got the odac with rca to connect but upon receiving both i come to find out the o2 doesn't have rca.

 

doh!

 

now i have to wait to ship out a proper cable so i can start listening, what type of cable would be better to go with? thanks in advance

 

there's a "fiio l2 3.5 to 3.5 cable" or there's a "mediabridge 3.5 to rca cable" around the same price.

 

would there be any difference in going straight from 3.5-->3.5 vs 3.5--->rca ??

 

oh and would i be able to plug headphones directly into the odac plugged into the computer through usb and listen to music while waiting for my new cable? or is that a big no go, do not enter area.

There shouldn't be any audible difference between 3.5->3.5mm vs 3.5->rca, but i prefer rca simply because it seems to be more robust.. I'm using BJC MSA-1 and I can only highly recommend it.

And yes, you can use your headphones directly from odac.. true, it's far from being ideal, as odac has way too high output impedance, but you won't damage anything.. only audio quality may suffer a bit.

Hope this helps:)

post #1604 of 3396
Quote:
Originally Posted by Dano91 View Post

There shouldn't be any audible difference between 3.5->3.5mm vs 3.5->rca, but i prefer rca simply because it seems to be more robust.. I'm using BJC MSA-1 and I can only highly recommend it.

And yes, you can use your headphones directly from odac.. true, it's far from being ideal, as odac has way too high output impedance, but you won't damage anything.. only audio quality may suffer a bit.

Hope this helps:)


thanks!

 

i might have to go with the mediabridge, that bjc is out of my price range. $34.50 for a 4 foot cable before shipping... the mediabridge has 900+ ratings on amazon and overall good rating... should be good enough for me.

post #1605 of 3396

Finally I've finished my o2 amplifier. This was my fist DIY audio project and I've learned a lot. 

It took me some time to put everything in place, but I am very happy with sound and how it looks smile.gif

I really enjoyed building o2 amp and hopefully my next project will be a tube amp.

Hope you like it smily_headphones1.gif

 

 

 

photo o2amp_09_zpseb9ae20c.jpg photo o2amp_03_zps0786f1f8.jpg photo o2amp_06_zpsc0102a98.jpg

photo o2amp_07_zps4db36951.jpg photo o2amp_10_zpsce39f4f7.jpg


Edited by aleksa - 8/11/13 at 5:21am
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