[PurpleAngel]

Quote:

RCA to mini? Hmm, would Radioshack maybe have such a cable? 
 
Also, would using the RCA outputs on the card vs the headphone out outputs offer better fidelity? 

The RCA outputs on the Titanium HD should give you a slightly cleaner analog audio signal over plugging the amp into the headphone jack.

 

[spaark]

Quote:

Interestingly, the O2 does seem to sound better than the E9K, but the E9K seems to have higher volume potential 

The E9K has two gain levels, 10 dB and 18 dB, or 3x and 8x respectively. The O2 has a lower gain. That's why it's louder.

 

[Aelemar]

Thank you very much for all your replies. I switched to the RCA outputs, and the slight hiss (its like a slightly hiss/pitched sound) still shows up at maximum volume. 
 
The O2's knob has to be between 75-100% of the way to maximum volume for the sound to be noticeable. 
 
At the most, with the computer audio at 100%, I only need to take the O2 to around 40-50% (at the 2.5x default gain, even less with higher gain) for comfortable gaming/music (as in, loud, but not too loud)
 
I am not sure it'd be possible to gain absolute silence. The sound card is close to the PSU (unable to place it anywhere else) plus well, bunch of components nearby (2x GPUs). 
 
I don't know much about audio, but I'd say that it's probably just a bit of interference. 
 
No idea, though I will never need to run the amp at 75% of higher volume (unless I want to blow up my eardrums), so the sound is inaudible to me at my normal listening levels. 

 

[Heretic817]

Ha. Sorry OP. You did not ask about the O2. But you should have

TBH I cant say that I have heard the O2 yet. Just that 20 Hz is fine for a low end but perhaps the ODA might have further bass extension like a low end response that starts at 10 Hz or something. I am not really interested in bass boost so much.

You are right I can't blame him for taking his time. Still if he does finish it and JDS picks it up it will probably be a better choice for a desktop amp.

That being said I almost ordered parts for the O2 last night. I wanna build it myself.

 

[Heretic817]

Oh. Hell. Well I have seen it but that was six months ago. I just thought I saw a published freq response of 20 Hz on the low end. Well whatever if you have heard it and it goes deep as in bass you can feel when its called for I take you word for it. All I know is I trust his numbers and I know other have preferences of their own but I want accurate reproduction above all else. I think you probably can't get better for the price. By better I mean look up electrical amplifier....see perfect theoretical amplifier.....then see design goals of O2. I am just not interested in the soul of a tube amp or whatever others are into. At any rate you don't have to sell me on it. I already want it or the ODA and at this point we have hijacked the OP's thread. So I won't say anymore about it.

 

[Heretic817]

As he pointed out above and he is probably right the 5x gain of the magni is probably excessive and could represent some sq problems. Also the 10ohm output impedance of the E9K is high and could cause base dampening problems. However it seems both are well liked for the Q701. So if I had to choose the lesser of two potential problems I would go with the FiiO as the output Z is at least near the reccomended 1/8 impedance of the headphone. You still might want to consder the O2 which would eliminate both potential issues. Don't get scared off though you would probaby be happy with any of the three for the price.

For the record I have not used any of these myself. I am in the exact same boat with trying to chose an amp for my Q701. I just have been doing a lot of reading and research and getting advice from this forum and others. So far I think I am just going to get the O2 because at least there is lots of data to prove that it is a good choice.

 

[Heretic817]

Just wanted to share my excitement. I just ordered all of the components including some upgrades from Mouser to build my own Objective 2 Amp.
I also ordered the chassis, front plate, knob, and PCB from JDS Labs. All done shipping and all for about $80!!

 

[Heretic817]

Yes, great... My list of upgrades on my unit:
 
 
1) Soldering silver (ODAC - O2 internal connection)
2) Cryo Silver OCC 24AWG (ODAC - O2 internal connection)
3) Better resistors
4) SIPs
5) Gold plated 8pin dip switches
6) Switchcraft RCAs
7) Switchcraft 1/4 output
8) long lasting capacitors
9) 15-650 wall transformer
 
It's a fully-desktop version of O2/ODAC combo, with 3 options of inputing signal to O2 (1/8 in, RCA in, internal connection from ODAC). However, I am not the builder so I do not know all the stuff accurately. The unit hasn't arrived yet but it is intended to let it last for years as I am pretty amazed what this amp and DAC can do for the price.

Not changing any resistors or caps though. Too worried about effecting noise by messing with design. Then again the schematic is open source and simple so if it fails I know I can repair it.,

 

[Heretic817]

And whats with the silver stuff????

 

[ostewart]

i use silver cables for interconnects, and silver plated for headphones, i can hear a slight difference in clarity and high frequency response "flame suit on"

 

[Heretic817]

Ok if you say so. As an engineering technician all I can say is that the best conductors are (OOPS!....fixed my error here) silver, copper gold. in that order but copper and silver have a common problem which is that they oxidize. Gold on the other hand does not but the prohibitive costs of gold and silver make copper the defacto conductor used in electronics. That being said the difference in electrical conductivity is a negligible amount especially at the low power levels in something like a headphone amp. No flames here but I cant explain why one wire would sound different than another other than bad connections, interference which can be a function of length, or under sized wire gauge.

 

[Heretic817]

oops! I can't believe I remembered this incorrectly. (As did two of my colleagues) Yes. Silver is best for outright conductivity but we commonly use gold flash on any important current pathway because of the corrosion problem. Still though we are talking about incredibly low amounts of lead resistance in short runs and low currents. I think you should invite some friends to take a "blind taste test" on this one. I think you will find your skepticism warranted.

In the end most of your signal path is going to be through copper anyway.

 

[MatsudaMan]

Fiio products break down after just a couple years.  They are cheap and unreliable Chinese crud.  Go for the Schiit - made by real people who actually care about their product and the buyer.

 

[ostewart]

Fiio products break down after just a couple years.  They are cheap and unreliable Chinese crud.  Go for the Schiit - made by real people who actually care about their product and the buyer.

Not so harsh mate, Schiit have had some problems, when turning off the Asgard, the first model used to push a surge of voltage through the headphone driver, which could damage it.
Fiio have some great products, yes they are not top of the market, but they make good products at an available price.

 

[MatsudaMan]

Quote:

Not so harsh mate, Schiit have had some problems, when turning off the Asgard, the first model used to push a surge of voltage through the headphone driver, which could damage it.
Fiio have some great products, yes they are not top of the market, but they make good products at an available price.

They are sub par products at best that take saturate the market and take away from great companies like Schiit and hardworking individuals like Ray Samuels and others.  Their products are very unreliable and are incredibly cheaply made - typical cheap Chinese labor and cheap plasticky parts.  
 
As for the Asgard, I'm sure you could send it back for a replacement, no questions asked and actually talk to a real person who knows a thing or two about customer service.  
 
I bet if you call a Fiios customer service line, you'll end up talking to someone in Bangladesh.  
 
Really sick of this cheap Chinese crap flooding the market.  And all the people who just eat it up without thinking of the consequences.