[adydula]

701's can and are in my case, very well even with batteries only.....not all small portable amps can do this well at all.
 
The O2 and 701/2's is not an issue.
 
I have three transformers of all sizes and have switched back and forth and compared to just batteries and there is no audible difference to
me at all.
 
I ususally listen to just batteries until they need charging and charge overnight and start the process all over again.
 
Alex

 

[HamilcarBarca]

Quote:

Quote:

If I can impose on you again, I have three questions. Both the Late, Lamented Lord and you mentioned low-impedance, low-sensitivity headphones. AKG rates their K701 at 62Ohms (and 105dB which seems efficient to me.) HiFiMan rates their HE-500 at 38Ohms (and 89dB.) 

If I recall correctly the AKG rating you listed is dB SPL/ V while the HE-500 rating is 89 dB/mW. The AKG is ~ 94 dB/mW but I'd double check that as it's off the top of my head.

 
I recall now, after looking at specs for six or so headphones, that some were rated in using dB SPL/V and some with dB SPL/mW. It didn't register with me at the time.

 

[Uberbob102000]

Yea, it got me at first too.

There's a formula to convert the two, but I don't have it on this computer and after being up for 32 hours of airports and planes I'm not sure I'll even copy pasta the right formula.

EDIT: Since I'm in the market for a DAC/amp again, how does the O2 drive the HD650? I know it drives the two Hifiman headphones I have/want but I haven't found a solid answer on the HD650.

 

[HamilcarBarca]

Quote:

There's a formula to convert the two, but I don't have it on this computer and after being up for 32 hours of airports and planes I'm not sure I'll even copy pasta the right formula.

 
V = IR & P = I²Z if I remember correctly. My question was academic, not interesting enough for me to compute even a few data points.
 

EDIT: Since I'm in the market for a DAC/amp again, how does the O2 drive the HD650? I know it drives the two Hifiman headphones I have/want but I haven't found a solid answer on the HD650.

 


It's the best setup I've heard yet. Assuming the HD-650 is to your liking, I recommend the setup highly.
Currently, my ODAC+O2 is at work and the HD-650's are at home. They were paired for a couple of weeks, and they made beautiful music together <3. Unfortunately, they didn't give me any kittens.
 
Tomorrow, the Beyer T70's, which I've now had for almost thirty minutes, goes to work where my ODAC+O2 lives.

 

[TunneLVisioN42]

Got my ODAC, Wondering what kind of 3.5mm cables you guys are using for Output/Input? Looking for something 8 to 12 inches?

 

[proton007]

Quote:

Got my ODAC, Wondering what kind of 3.5mm cables you guys are using for Output/Input? Looking for something 8 to 12 inches?

I just got a standard cable, nothing fancy. You can get the monoprice cables with gold plated jacks.

 

[TunneLVisioN42]

Yeah I was looking at the monoprice 1.5FT gold plated cable but its a bit long, the FiiO L2 is a bit short.

Also ODAC sounds great but I often use Teamspeak and my USB Microphone absolutely refuses to work along side my ODAC, I have had this issue before with another USB DAC, it only happens when I try to use USB devices for both MIC and Output so its a software issue.

Anyone know why this is?

Edit: Seems its not limited to Teamspeak but windows is causing it.

2: Yeah If the ODAC is in use, and I enter the recording panel in the sound options the control panel will freeze, If the ODAC is not in use but still selected as default playback and I enter the recording section once more it shows it is working fine and picking up my voice.

Quite frustrating

 

[proton007]

Quote:

Yeah I was looking at the monoprice 1.5FT gold plated cable but its a bit long, the FiiO L2 is a bit short.

Also ODAC sounds great but I often use Teamspeak and my USB Microphone absolutely refuses to work along side my ODAC, I have had this issue before with another USB DAC, it only happens when I try to use USB devices for both MIC and Output so its a software issue.

Anyone know why this is?

Edit: Seems its not limited to Teamspeak but windows is causing it.

2: Yeah If the ODAC is in use, and I enter the recording panel in the sound options the control panel will freeze, If the ODAC is not in use but still selected as default playback and I enter the recording section once more it shows it is working fine and picking up my voice.

Quite frustrating

 
I'm not completely sure, but does this occur on your computer, or have you duplicated it on some other system? It may be a power issue.

 

[HamilcarBarca]

Quote:

Got my ODAC, Wondering what kind of 3.5mm cables you guys are using for Output/Input? Looking for something 8 to 12 inches?

 
I just received, from Amazon, a 1.5' extension cable made by Cables to Go (~$4.)
 
We have a local mom-n-pop shop which sells no-name Chinese cables and some Monoprice cables. The tech will assemble custom cables even with customer-supplied parts.

 

[TunneLVisioN42]

I've had this same issue with 2 other USB based DAC's, my friend has never had this issue, I don't know if its power though what would the issue be stemming from? USB power output? I guess that could be it I will try to replicate it on another computer and share the results

Edit: Cannot replicate results on another computer, I suspected it was my computer anyways not the actual devices, I have scoured google and have only found 1 person that had the same issue and  the poor guy did not get a reply, anyone have an idea of how to start troubleshooting this? I have not had any issues with non audio USB devices.

 

[proton007]

Quote:

I've had this same issue with 2 other USB based DAC's, my friend has never had this issue, I don't know if its power though what would the issue be stemming from? USB power output? I guess that could be it I will try to replicate it on another computer and share the results

Yeah, possibly your USB ports cannot power two of these devices at once.

 

[Uberbob102000]

Yeah, possibly your USB ports cannot power two of these devices at once.

Good way for him/her to test that would be to get a powered USB hub and see what happens.

 

[TunneLVisioN42]

Here is my motherboard http://www.asrock.com/mb/Intel/P55%20Extreme/ It lists a "Powered eSATA2/Usb Port" I was wondering if this was powered separate from the other USB ports on my motherboard? By the way I also have an older but competent 600w PSU with 40amps on the 12V.

Is there anything anyone can suggest in the meantime before I purchase a powered USB Hub?

 

[DairyProduce]

Having a O2/ODAC combo, I was wondering. What would be considered an upgrade for this combo?

 

[proton007]

Having a O2/ODAC combo, I was wondering. What would be considered an upgrade for this combo?

Depends on what kind of upgrade you're looking for. I feel an inbuilt power supply would be good for start.