iFi Audio Nano iDSD discussion + impression

[ClieOS]

  I made a video to send ifi check it out https://www.youtube.com/watch?v=rRc39BLoTQg

 
What you have described in the video (which is much clearer than what you have written so far) is a strong indication of ground loop. Basically there is a voltage/current difference (that isn't supposed to be there) between the amp (plus the DAC) and the PC and causes the current to 'flow' in a way that it isn't designed to, and the result is the humming noise. The fact there nothing is actually connect to a ground isn't helping either.

 

[natra084]

   
What you have described in the video (which is much clearer than what you have written so far) is a strong indication of ground loop. Basically there is a voltage/current difference (that isn't supposed to be there) between the amp (plus the DAC) and the PC and causes the current to 'flow' in a way that it isn't designed to, and the result is the humming noise. The fact there nothing is actually connect to a ground isn't helping either.

iFi told me that a shouldn't connect to a ground connection so I didn't but in my home I have grounded and unground connections so I wanted to show iFi that I had connected as they told me so I connected to the unground otherwise I always use ground connection

 

[Pwnsaur]

 
Here's a better option for you....   having all of the equipment your asking about I think I can answer you pretty well...  
For the 7XX...    the Nano does "just" drive them...  I can turn the volume control all the way up and can listen at that level all day...  its loud but not too loud... but...      
I also have mounted an O2 with my Nano...  in that configuration you turn the volume knob on the Nano to full on power and it turns the output to a Line Out just like a pre amp...  
With this Nano/O2 the 7XX are driven much better...   you can use high gain or low gain and have plenty of power...  more than enough power..   
The way I mounted the two...   the O2 case can be purchased with rubber end bumpers...  they look great and work very well...  
The Nano sits on top of the O2 and then two bands hold it all together...   a super nice package that not only works with computer/laptop but also Iphones...  
Now to the question of the DAC...   the ODAC was an after thought to the original O2.. its a pretty nice solution for folks that wanted a O2 DAC combo...  there are two downsides though that you might consider...   when the DAC was added to the O2 there wasn't any room for the batterys...  so you have to run the O2/DAC off of main power...  so your portability goes away..  and the DAC itself is not a world class updated DAC as that used in the Nano...  it will not work with DSD files....  
So your playing only FLAC and say you don't think you need a DSD DAC....   well you don't need to have DSD files to use a DSD DAC... using JRiver Media Center 20 you can take all of your songs and have it upsample all of your songs to DSD output into the Nano...   it will even make your MP3 songs a little better during playback...  
And if you ever do deside to get DSD files (some are free) then you would have the Nano for those songs...  thats not an option for the ODAC ever..  
So,  Start out slow...  get a Nano...  than later add the O2 ...   you'll enjoy the 7xx with the Nano and have a good upgrade path to look forward to later...   

Thanks for the advice, I'll probably give the iDSD a spin... now to scrape the cash together >.< 

 

[Kane Williams]

If you run just a phone into the Nano, with headphones plugged in, is there any hum? If so, this cannot be a ground loop, as everything is battery powered.

 

[iFi audio]

If you run just a phone into the Nano, with headphones plugged in, is there any hum? If so, this cannot be a ground loop, as everything is battery powered.

 
Hi,
 
We looked into the support ticket Natra kindly opened with us.
 
As TF1296 said, try another DAC.
 
Natra did - he tried another DAC - the noise was much worse with the other DAC. Therefore we immediately ruled out the nano iDSD from the equation.
 
We are trying to work through the electrics-something is at odds.
 
If anybody would like some background on tracking down ground loops, we can upload that information here for future reference.
 
Cheers.

 

[technobear]

 

What you have described in the video (which is much clearer than what you have written so far) is a strong indication of ground loop. Basically there is a voltage/current difference (that isn't supposed to be there) between the amp (plus the DAC) and the PC and causes the current to 'flow' in a way that it isn't designed to, and the result is the humming noise. The fact there nothing is actually connect to a ground isn't helping either.

iFi told me that a shouldn't connect to a ground connection so I didn't but in my home I have grounded and unground connections so I wanted to show iFi that I had connected as they told me so I connected to the unground otherwise I always use ground connection

Can you leave out the DAC and just connect an analogue source to your tube amp. You could try the analogue output from a phone or a laptop perhaps. Does the noise still occur? Sounds like your tube amp may be faulty.

 

[h1f1add1cted]

  Hi guys why is this nano draining my phone's battery

Thats "normal", the nano iDSD runs on battery yes, but a USB signal still consums some energy, it would drain much faster if the devices would not provide a battery.
 
My Sony phone runs with the nano iDSD easily 15 hours connected with USB.

 

[natra084]

Hi guys I make a YouTube video https://www.youtube.com/watch?v=aVROnJ5N-P8 it isn't the best one.

 

[h1f1add1cted]

The nano iDSD has "only" 130 mW @ 16 ohms, the volume knob is more like a attenuator. If you need more power (and still the same size and price range), the nano iCAN would be with 150 mW @ 32 ohms with up t o 18 dB gain the better option. Or if possible go for the micro iDSD still portable but extremely powerful AMP and great DAC with a tons of other nice features in one single device. And I fully agree with you - really good support by iFi

 

[technobear]

The nano iDSD has "only" 130 mW @ 16 ohms, the volume knob is more like a attenuator.

At the risk of being pedantic, ALL volume knobs are attenuators.

 

[natra084]

The nano iDSD has "only" 130 mW @ 16 ohms, the volume knob is more like a attenuator. If you need more power (and still the same size and price range), the nano iCAN would be with 150 mW @ 32 ohms with up t o 18 dB gain the better option. Or if possible go for the micro iDSD still portable but extremely powerful AMP and great DAC with a tons of other nice features in one single device. And I fully agree with you - really good support by iFi

the only reason I took up the volume question is because there are people out there the think that is going to be a big improvement on the volume but that isn't the case.

 

[natra084]

At the risk of being pedantic, ALL volume knobs are attenuators.

That's true but the average guy doesn't know that. they know it as a volume knob

 

[Kane Williams]

I don't believe all volume knobs are simply attenuators. Only passive ones are. For instance my Denon amp displays -dB or +dB values so any + is surely adding gain. However my SM Pro Mpatch2 will only attenuate as it is passive, so it goes from 0dB to -50dB (or something like that).

 

[ClieOS]

There are many ways to implement volume control schemes. Though not all volume control are used for attenuation, most are. Sometime it can be a bit of both, sometime it can be a gain control (which I often find not to be great).

 

[Kane Williams]

There are many ways to implement volume control schemes. Though not all volume control are used for attenuation, most are. Sometime it can be a bit of both, sometime it can be a gain control (which I often find not to be great).

Good to know. I wonder why in Pro Audio then, passive controllers such as my MPatch2 are not that common, most monitor controllers (volume controls) are active, as in need electricity to power them? If a device only has to be able to attenuate a signal, why aren't they all passive and thus add close to zero colouration to a signal? Sorry, this is off topic.