[skamp]

NwAvGuy, like any other objectivist, would say that the differences you hear would probably vanish in a proper double blind test. Haven't you read his blog?

 

[tdockweiler]

Quote:

NwAvGuy, like any other objectivist, would say that the differences you hear would probably vanish in a proper double blind test. Haven't you read his blog?

Yes, and you'd also probably fail a blind test between an E9 and O2.
I guess we should just go out and buy an E9 since it's cheaper...
 
EDIT: ok i'm partially joking, but I wouldn't be surprised if 75% of us would fail that. No I'm not kidding.
 
Honestly I could not live with silver wire on anything that's bright. If that's me hearing things, then so be it..
If someone could live with the K702 with silver for a month, i'll personally mail you a check for $500. Not even a K702 fan could do it!
It'd drive me crazy. The O2 or Magni would even make it worse.

 

[skamp]

The E9's high output impedance (that's measurable!) would probably have caused a high frequency spike of several decibels (that's measurable too!) with my balanced armature Shure SE425 IEMs. I wanted an amp/DAC combo that would work well with any headphones/IEMs, and with good build quality. My FiiO E7 developped contact problems on both headphone outs after only a couple of months, so I didn't want to risk buying anything more from FiiO.

Now that I have my O2/ODAC, I don't need anything else. And yeah, I probably couldn't differentiate it from some other, cheaper gear that measures well (e.g. a FiiO E7), but I don't claim that I could, and I don't care. It's fully transparent, and that's exactly what it was designed to achieve. Also, it gives me a warm fuzzy feeling of overkill.

 

[tdockweiler]

Quote:

The E9's high output impedance (that's measurable!) would probably have caused a high frequency spike of several decibels (that's measurable too!) with my balanced armature Shure SE425 IEMs. I wanted an amp/DAC combo that would work well with any headphones/IEMs, and with good build quality. My FiiO E7 developped contact problems on both headphone outs after only a couple of months, so I didn't want to risk buying anything more from FiiO.

Now that I have my O2/ODAC, I don't need anything else. And yeah, I probably couldn't differentiate it from some other, cheaper gear that measures well (e.g. a FiiO E7), but I don't claim that I could, and I don't care. It's fully transparent, and that's exactly what it was designed to achieve. Also, it gives me a warm fuzzy feeling of overkill.

 
I agree with that, but it's a bit annoying how people claim every headphone under say 80 ohm is going to magically be altered. The Q701 doesn't change a bit with the E9's 10 ohm output impedance. I can't even get that to change with even my 330 ohm receiver. My 38ohm DJ100 is perfect too. I know the E9 is no transparent "wire with gain".

It still sounds pretty good, but the Magni is more accurate. Sometimes I don't need 100% accuracy.
 
I know this sounds nuts, but I'd probably fail an extended blind a/b test with my Magni and E9, but am pretty confident i'd pass one between a headphone using silver wire and say Canare. Crazy right? To me the difference is like comparing an O2/Magni to a tube amp

It all depends on the amp/dac too. I've noticed it was easier to tell the difference between cables with my HRT MSII compared to the ODAC. Not sure why.
 
The difference between my Micro Amp, E9 and Magni sure isn't very huge, but that's obvious. I still am tempted to try the O2 and compare it.
 
I know this will annoy someone, but I do wonder if the O2 has maybe an ultra tiny touch of warmth. The Magni seems pretty cold and analytical. Well I guess they're both dead neutral/transparent.
Some amps that are still very transparent still seem to have a little bit of warmth. I mean not enough to really change ANY headphone. My Micro Amp sounds very slightly warm compared to the Magni (and probably O2) and I thought that was impossible. It's actually less warm than my Clip+. I also never thought an amp could make my E9 sound warm.

 

[skamp]

I agree with that, but it's a bit annoying how people claim every headphone under say 80 ohm is going to magically be altered. The Q701 doesn't change a bit with the E9's 10 ohm output impedance.

That's not speculation on my part, I've measured it, though with a lower output impedance (5.5Ω). The variation in frequency response that I will witness with my IEMs as output impedance grows, is a boost in the high frequencies. Also, there's nothing magical about it, it's just basic physics. It might or might not be annoying, given that there's little content past 10 kHz or so. But what if I buy new IEMs later on, and their impedance varies in a region that's more problematic, like in the mids? I would hate overemphasized mids.

Also, the 10Ω impedance is on the 1/4" jack, which would require the use of an adapter for no good reason. The 1/8" jack's impedance is 43Ω!

 

[tdockweiler]

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That's not speculation on my part, I've measured it, though with a lower output impedance (5.5Ω). The variation in frequency response that I will witness with my IEMs as output impedance grows, is a boost in the high frequencies.

Also, the 10Ω impedance is on the 1/4" jack, which would require the use of an adapter for no good reason. The 1/8" jack's impedance is 43Ω!

 
Oh I know..I totally wouldn't use an IEM with it I think. It's just that i've yet to have anything not work well with the E9. I guess i'm lucky.
 
I get super annoyed when people seem to think like the Q701 is TERRIBLE with the E9 without trying it, when it fact it's VERY good.
 
The E9 is still a steal for $88..yeah the Magni (or O2) is technically better. If I had to pick between the Magni and E9 for just the Q701..I don't know what i'd pick. The E9 does sound a bit more colored and "musical". Ugh..am I calling the E9 musical?
 
For some reason I find the 1/8" jack to sound a bit worse and not just due to the 43 ohm output. Probably hearing things. Seems like I get a reduced soundstage(!) and a warmer sound.
Why is it that when a headphone gets warmer, my soundstage shrinks?

Stupid brain tricking me!
 
BTW I tried my 36ohm KRKs with my 330 ohm output impedance receiver..now THAT was amusing. It sounded almost cave like. Totally ruined it. My DJ100, HD-650 and Q701 were fine though

 

[adydula]

The E9 with a 10 ohm output will degrade the sound with some headphones.
 
Cans having a high impedace greater than 80 ohms are the best to use with it.....
 
Other than that nwavguy has done a review of this amp and gave it a very good writeup....
 
Wait...wasnt this an JDS O2 Black edition O2/ODAC discussion???
 
Alex

 

[tdockweiler]

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Originally Posted by adydula /img/forum/go_quote.gif
 
Wait...wasnt this an JDS O2 Black edition O2/ODAC discussion???
 
Alex

 
Nothing wrong with comparing the O2/ODAC to other amps..
 
Maybe the O2 isn't the world's most transparent amp after all.
 
It's the E9!!!

 
I still need to get the O2 to compare to the Magni. Maybe the Magni is really not as good as the O2 (to my ears).

 

[miceblue]

Quote:

The E9 with a 10 ohm output will degrade the sound with some headphones.
 
Cans having a high impedace greater than 80 ohms are the best to use with it.....
 
Other than that nwavguy has done a review of this amp and gave it a very good writeup....
 
Wait...wasnt this an JDS O2 Black edition O2/ODAC discussion???
 
Alex

Isn't the general rule of thumb to have a load/headphone impedance at least 8 times that of the source's output impedance?
If so, does that still apply to every-day earphones with a typical impedance rating of 16 ohms? And if yes, from what I recall, iPods tend to have a high output impedance (something like ~7 ohms), wouldn't the earphones be....not optimal-sounding (I don't know what happens when the output/source impedance ratio is less than 8)?

 

[xnor]

Quote:

 
Nothing wrong with comparing the O2/ODAC to other amps..
 
Maybe the O2 isn't the world's most transparent amp after all.
 
It's the E9!!!

 
I still need to get the O2 to compare to the Magni. Maybe the Magni is really not as good as the O2 (to my ears).

NwAv also 'reviewed' the E9, but I guess you already knew that. It can output more power into low impedance headphones (I guess no or higher current limit), has a higher noise floor, and well the higher output impedance.
 
You can always increase the output impedance by adding a resistor in series with each headphone driver. On the O2 you can also replace the output resistors (2x 1 ohm in parallel = 0.5 ohm output impedance) to pretty much any higher value you like.

 

[xnor]

Quote:

Isn't the general rule of thumb to have a load/headphone impedance at least 8 times that of the source's output impedance?
If so, does that still apply to every-day earphones with a typical impedance rating of 16 ohms? And if yes, from what I recall, iPods tend to have a high output impedance (something like ~7 ohms), wouldn't the earphones be....not optimal-sounding (I don't know what happens when the output/source impedance ratio is less than 8)?

If it's a dynamic driver the bass will become a bit looser/boosted. If it's a multi-driver IEM with crossovers you have to look at the impedance curve to see what happens. Could be anything from bass to treble boosts. But we're talking small differences here.

 

[Satellite_6]

Wow the new version looks stunning, I just missed it unfortunately. :| I am very much enjoying my boring silver one tho. 
 
Some additional stuff I wanted to say after reading the thread, not very organized: 
 
It was in fact designed as a portable amp.
 
The HD 650's sound great out of the O2. They are smooth an muscial and the O2 doesn't add anything to that obviously.
No "synergy" is necessary to get the most out of them.
Calling them inaccurate and veiled is ********. Do not claim everything is subjective and then say they are inaccurate crap. 
For that you would have to break out frequency plots and a lot worse looking ones than the HD 650's exist for sure. 
Not everyone likes their sound signature and that's fine. . . 
 
The LCD-2's are not that hard to drive so the O2 can surely dive it "to its full potential in the bass department."
 
You should not use the high gain mode with the ODAC, so 2.5X is probably a better idea than only 1X just in case. i.e. 1X would be marginal to get the HD 650's very loud.
 
Oh god it's that cable guy. No comment. 

 

[tdockweiler]

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Oh god it's that cable guy. No comment. 

 
Are you referring to me? Please don't tell me I hurt your feelings because I actually have an opinion about cables that's different from yours.
 
 
I must be really stupid for buying $5 Monoprice snake oil! What was I thinking...I knew I should have went to the dollar store danggit.
 
If synergy wasn't important you could buy any crappy mis-matched amp and dac and be done with it. The HD-650 sounded awful with the wrong DAC IMO.
Yes, transparent gear seems to be best for it. I haven't heard the veil yet on this HD-650. I've been through 3 amps just for the HD-650 and Q701. This was before the O2/Magni though.
 
As much as I love the HD-650 I don't find it dead accurate. Fairly accurate but they make everything sound good. I won't say they dramatically change my music, but it's very obvious everything sounds a bit too good.
This is with the Magni+ODAC. This is not news to anyone..

 

[miceblue]

This is probably going to end up sounding like a really dumb question, but 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. It's not what an audiophile would consider "good", but aren't most DAC's these days actually pretty decent in terms of audible differences, not measurements? My iPod Video has pretty good sound quality compared to the 2nd gen iPod Touch, but I don't know if that's due to the DAC (Wolfson vs Cirrus) or if it's due to the amp....I should really get one of those LOD's in the near future, shouldn't I?
 
The whole Objective theme for Voldemort's projects is really intriguing to me. It boggles my mind how companies can charge so much for a product that doesn't even perform at its maximum potential (relating to Voldemort's process of getting the most out of the components). I mean, the most expensive part of the O2's circuit is the push switch (a whole whopping $1.60 per piece), it can't possibly take that much money to make a solid state amplifier. I was really surprised at how the O2 performed against other "bigger" and more expensive amplifiers at the last Head-Fi meet. If you can't tell by now, I think I'm pretty much set on my "journey" to find an amp. It was the quickest one yet!

 

[tdockweiler]

Quote:

This is probably going to end up sounding like a really dumb question, but 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. It's not what an audiophile would consider "good", but aren't most DAC's these days actually pretty decent in terms of audible differences, not measurements? My iPod Video has pretty good sound quality compared to the 2nd gen iPod Touch, but I don't know if that's due to the DAC (Wolfson vs Cirrus) or if it's due to the amp....I should really get one of those LOD's in the near future, shouldn't I?
 
 

 
The onboard sound you have is probably very flat and accurate. I know this sounds hard to believe, but my "crappy" Realtek HD sounds better than the Fiio E10 and a lot of other DACs. Mine is even labeled as having a headphone amplifier built in(!). This is on my MSI motherboard! Bizarre.
Based on my experience, some of my headphones have benefited very little from DAC upgrades. It seems that my HD-650, DJ100 and Q701 have the most. My HD-598 doesn't seem to change a bit with anything. Not even my HD-600 does much as long as it's properly amped.
 
To me the Ipod Video sounds a bit warmer than the Ipod Touch 2G. The Ipod Video 5.5 supposedly has slightly forward upper mids and rolled off low bass.
 
The Ipod Touch 2G to my ears sounds very similar to my Magni+ODAC. Even brighter at times, which is weird.I think the Ipod Touch 2G is ruler flat, but sounds like it has sort of edgy treble.
Despite bypassing the onboard amp, they still seem to have the same exact signature when using the LOD cable. What's interesting is that even the Ipod Docks have a DAC chip built inside of them. Not sure why..
 
Sometimes I think this LOD cable = better sound is hogwash. I can't hear any distortion from using my Fuze's headphone out to amp. I'm sure it's there.
 
One thing I noticed about the ODAC is that it's treble seems way smoother than 5-6 of my full sized CD players. Not sure why, but it's hard to believe all those are that much worse..
It's not coming from my amp..my amp has no rolled off treble or anything. I highly doubt the ODAC has rolled off treble..