Hey I have SigDJs and I'd like to get a good dac + amp combo. Could someone tell me if its a good match? I'm not sure what I should check except amp output impedance which seems to be fine if I'm not completely lost :D

Quote:

Originally Posted by Stratok 

Hey I have SigDJs and I'd like to get a good dac + amp combo. Could someone tell me if its a good match? I'm not sure what I should check except amp output impedance which seems to be fine if I'm not completely lost :D

What's a SigDJ?

Unless there's something very unusual about them, the ODAC+O2 combo will work just fine.

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Originally Posted by HamilcarBarca 

 

What's a SigDJ?

 

Unless there's something very unusual about them, the ODAC+O2 combo will work just fine.

Ultrasone Signature DJ sorry.

Quote:

Originally Posted by Currawong 

 

I agree with what you guys say. I pinched a friend's ODAC while we were in Tokyo for a while so I could give it a run. On sonic merit alone (ignoring everything else) the ODAC + O2 combo is great. The closest I've come across would be the Dragonfly or Audio-gd NFB-16 (not currently available) which are, respectively, a little flatter and a little-less-clear-but-more-musical sounding.

 

Some observations:

 

The ODAC isn't the first to use the output straight from the DA chip. The Metrum Octave does the same trick. The downside of this is that it depends on the amp used having a good input stage. Likewise, the ODAC sounds better with better power feeding it. The slight harshness in the sound disappears if I plug it into my Vaunix USB hub (designed for their lab-use signal generators). If I then feed the output into my Phoenix, which makes most DACs sound excellent, I could just about fool myself into thinking I'm listening to my main DAC + digital accessories.  Other amps I've tried don't fare as well. The ODAC and O2 were designed for each other, so, not surprisingly, work perfectly together.

 

The O2 doesn't seem to deliver the dynamics of music as well as much more expensive amps, so the overall O2/ODAC combination sounds a little flat in comparison but does a lot better than quite a few more expensive amps. I'd rather listen with the combo than a lot of other gear I've had pass through here that didn't impress as much, but cost a lot more.

Really agree. In the category of transparent and flat, it performs way beyond it's price point.     But I wish the O2 was a little more dynamic and musical.  Sometimes it's just little too flat and sterile with my headphones. 

Quote:

Originally Posted by cubusmybro 

Don't want to start a new thread so I thought I will post here. I bought an O2+ODAC yesterday and I am looking to buy some headphones to use with it. Originally I was thinking of buying the ATH-M50 for $109, but I heard amping it wouldn't do much and if I get something more expensive I could really unlock the full potential of the amp.
If I get something under $300 I will be able to buy the headphones by Christmas. If I wait I can get something up to $400 but not over. I have seen a lot of talk about the HE-400 and it looks pretty sweet. The only thing is that is was designed to not need an amp.
With a nice amp and DAC I think I could drive quite a few sensitive headphones quite easily.
$300 or less would be great but waiting after Christmas for the HE-400 makes a substantial difference I will wait.
If anyone could weigh in it would be great.

What?  You bought an amp and want to buy 'phones to match it?  Why?

A bit like saying you have a tank full of hi-octane fuel and now you're looking to buy a highly-tuned car to unlock its potential...

As an aside, sensitive phones generally benefit less from amping.  Having an amp will allow you to drive higher-impedance phones, as a rule.  What sort of sound signature do you like, anyway?  You'll also want to make sure you're using decent source material (FLAC, IMO, or at the very least 320kb/s MP3)

Quote:

Originally Posted by Smoke Signals 

Does anyone know how many watts the O2 can push at around 32 ohms?

Approximately up to 0.6W on AC power, 0.5W on batteries (half-full charge), per channel.  Listed measurement is 613 mW into 33 ohms on AC and 534 mW into 33 ohms on batteries at 1% THD—with a sharp knee, so under 0.01% until just before that point.

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Originally Posted by mikeaj 

 

Approximately up to 0.6W on AC power, 0.5W on batteries (half-full charge), per channel.

Hmm, so it falls very short in delivering 1 W per channel, man I'm getting a lot of mixed message about the O2 + HE-500.  Some are saying the O2 won't power it and it gives poor dynamics and others are saying it works fine and delivers plenty of power.  This is pretty frustrating.

Quote:

Originally Posted by Smoke Signals 

Hmm, so it falls very short in delivering 1 W per channel, man I'm getting a lot of mixed message about the O2 + HE-500.  Some are saying the O2 won't power it and it gives poor dynamics and others are saying it works fine and delivers plenty of power.  This is pretty frustrating.

I think the mixed message comes from that: the O2 has enough power to give it all the volume you need.  But it does not have the power to give it the headroom and dynamics.

Quote:

Originally Posted by sling5s 

I think the mixed message comes from that: the O2 has enough power to give it all the volume you need.  But it does not have the power to give it the headroom and dynamics.

Go to his blog, find "O2 summary" article and search for "LCD-2" or "Hifiman"...

O2 is powerful enough to drive LCD-2, HE-500 and even HE-6 (according to nwavguy). Especially if you use SIPs that allow you to change gain resistors to fit your needs better. Of course DO NOT USE BATTERIES FOR POWERING HERE...

HE 400 is definitely worth the extra cash.

HE 400 does need to be amped no matter what people say.

I am listening to my pair right now on a Fiio E7 and it doesn't really cut it.

I am looking to get an O2/ODAC over Christmas unless someone special rises from the grave and mentions the ODA.

If you can wait and spare the cash I would definitely jump on the HE 400 bandwagon.

Quote:

Originally Posted by cubusmybro 

With a nice amp and DAC I think I could drive quite a few sensitive headphones quite easily.
$300 or less would be great but waiting after Christmas for the HE-400 makes a substantial difference I will wait.
If anyone could weigh in it would be great.

Dude -

Get the HE-400s + Velour pads and don't look back. They are truly awesome.

I use mine with an O2. It is true they don't "need" an amp, but I promise they will love you for having one. The O2 will drive them loud and hard.

In terms of SPL / Volume, I got my O2 with the stock 2.5X gain and 6.5X gain. More than enough for my music, and plenty for movies / music DVDs and the like. Because the O2 can do a solid half-watt (and I estimated 700 mWs plugged in @ 50 Ohms), you would need a full watt for the next 3 dB in SPL, 2 watts for 3 more, etc. In short, you won't find more (clean) power for that sort of price. Major diminishing returns after that first half-a-watt.

If you decide to get some highly efficient headphones, you may be pissed you got the amp (if gain settings aren't like, 1X and 2.5X). You can barely twist the knob before threatening to blow up some phones.

I think that's what I'll do but I just saw another set of headphones, the Beyerdynamic DT 880 Premium 600 OHM and with the O2+ODAC it looks like these will really shine. Do you still think the HE-400 will be the best bet?