[a-LeXx]

I measured this with a timer, in stand-by DFC actually consumes 2.5x more power than a DFR.
On my iPhone 6, an average battery discharge in idle with DFR connected is 4% per hour. With DFC connected it's 10% per hour.

I did some research and found out the reason for this. Apparently, according to Gordon Rankin, DFC is operatig on USB in a High-Speed-Mode, vs. DFR in Full-Speed-Mode.
High-Speed-Mode needs A LOT more power just for the USB, as it allows transfer rates of up to 480 Mbps vs 12 Mbps in Full-Speed-Mode, has shorter latencies, more complicated packet structure and so on.

So, the question is: WHY?
At it's highest rate, DFC can work at 96/24, which means around 4.6 Mbps. This is almost 3 times less, than Full-Speed-Mode would allow to transmit. Conclusion is, Audio Quest must be planing to make higher sampling rates possible, up to 384 Ksps, which indeed would require High-Speed-Mode.
However, another question, why didn't they do it from the beginning? Why letting DFC running in a High-Speed-Mode (and this was the only reason for them to switch to a new MCU, because the old one was not power efficient/fast enough to run High-Speed-Mode, again according to Gordon Rankin, I'm not making this up) even though no higher sampling rates have been implemented? This unnecessary increases power consumption, and is doing NOTHING for audio quality, the energy is just wasted on USB protocol overhead...

Questions, questions....

 

[Chikolad]

I measured this with a timer, in stand-by DFC actually consumes 2.5x more power than a DFR.
On my iPhone 6, an average battery discharge in idle with DFR connected is 4% per hour. With DFC connected it's 10% per hour.

I did some research and found out the reason for this. Apparently, according to Gordon Rankin, DFC is operatig on USB in a High-Speed-Mode, vs. DFR in Full-Speed-Mode.
High-Speed-Mode needs A LOT more power just for the USB, as it allows transfer rates of up to 480 Mbps vs 12 Mbps in Full-Speed-Mode, has shorter latencies, more complicated packet structure and so on.

So, the question is: WHY?
At it's highest rate, DFC can work at 96/24, which means around 4.6 Mbps. This is almost 3 times less, than Full-Speed-Mode would allow to transmit. Conclusion is, Audio Quest must be planing to make higher data rates possible, up to 384 Kbps, which indeed would require High-Speed-Mode.
However, another question, why didn't they do it from the beginning? Why letting DFC running in a High-Speed-Mode (and this was the only reason for them to switch to a new MCU, because the old one was not power efficient/fast enough to run High-Speed-Mode, again according to Gordon Rankin, I'm not making this up) even though no higher sampling rates have been implemented? This unnecessary increases power consumption, and is doing NOTHING for audio quality, the energy is just wasted on USB protocol overhead...

Questions, questions....

We need Gordon in here

 

[McCol]

I wonder if drain is different on Android, I'm not seeing anything like 10% drain per hour via my Samsung handset.

 

[a-LeXx]

I wonder if drain is different on Android, I'm not seeing anything like 10% drain per hour via my Samsung handset.

Well, first thing, iPhone 6 has a really small battery, android devices usually have a battery which is 2-2.5 times larger.
Second factor is, that iPhones don't have USB. USB is provided as 'emulation' by an MCU on a CCT. And of course it's also more power consuming to emulate USB High-Speed-Mode than Full-Speed-Mode, this is also havin a share in increased power consumption...
Bottom line is - DFC is running in a High-Speed-Mode while even the Fast-Speed-Mode wasn't even remotely exhausted, without real technical need for that.

As Gordon pointed out, the whole DFC concept was even brought to life by AQ's attempts to use the High-Speed-Mode. They failed with an original MCU and were ready to abandon the project (power budget violation for iOS devices), but then they've got a new MCU and were able to make it work without a power budget violation. So, why the whole fuzz, if DFC still only accepts 96/24 max? Currently, it's a perfect example for over-engineering, which only introduces negative aspects (high battery drain) without any benefits at all...

 

[Chikolad]

I wonder if drain is different on Android, I'm not seeing anything like 10% drain per hour via my Samsung handset.

Drains my LG v20 very quickly, especially if I'm using it at the time. But it's an old phone...

 

[Chikolad]

So 2 days ago it finally happened. Something clicked.
I don't know if it's in my brain or in the unit itself, but all of a sudden things fell into place and I could hear what everybody was talking about.
The highs are smoother now, and everything blends together instead of having a detailed sound where the details feel detached from the rest of the image.
What's more, I no longer feel the need to EQ my i3 and can use bit-perfect playback on UAPP and enjoy MQA.

Using a PC / laptop some albums can still sound too harsh. Through my phone that harshness is reduced. But it's the same using the Mojo (even with using a Jitterbug).

Overall I'm happy now and I don't have to limit myself to LG for my next phone!

 

[a-LeXx]

So 2 days ago it finally happened. Something clicked.
I don't know if it's in my brain or in the unit itself, but all of a sudden things fell into place and I could hear what everybody was talking about.
The highs are smoother now, and everything blends together instead of having a detailed sound where the details feel detached from the rest of the image.
What's more, I no longer feel the need to EQ my i3 and can use bit-perfect playback on UAPP and enjoy MQA.

Using a PC / laptop some albums can still sound too harsh. Through my phone that harshness is reduced. But it's the same using the Mojo (even with using a Jitterbug).

Overall I'm happy now and I don't have to limit myself to LG for my next phone!

I guess it‘s more a brain burn in. You see, Mojo is using a brick-wall filter, DFC a minimum phase filter, that as a downside introduces some minor phase shifts at certain frequencies. However, a human‘s brain is very sensitive to phase shifts. So, probably your brain had to ‚learn‘ first to accept those minor phase shifts.
And yes, tidal with MQA is really nice sounding, never harsh, sometimes better than uncompressed hires versions of the same tracks. I guess they are applying some additional filtering at mastering stage when mastering for MQA...

 

[Chikolad]

I guess it‘s more a brain burn in. You see, Mojo is using a brick-wall filter, DFC a minimum phase filter, that as a downside introduces some minor phase shifts at certain frequencies. However, a human‘s brain is very sensitive to phase shifts. So, probably your brain had to ‚learn‘ first to accept those minor phase shifts.
And yes, tidal with MQA is really nice sounding, never harsh, sometimes better than uncompressed hires versions of the same tracks. I guess they are applying some additional filtering at mastering stage when mastering for MQA...

Yes, I also lean towards my brain being the culprit. My brain is used to Mojo and Hugo 2. Chord DACs also take some adjusting of the brain (they sound good to begin with, but better after adjusting). Not sure which filter the LG uses.

 

[a-LeXx]

Yes, I also lean towards my brain being the culprit. My brain is used to Mojo and Hugo 2. Chord DACs also take some adjusting of the brain (they sound good to begin with, but better after adjusting). Not sure which filter the LG uses.

I thought you can even select a filter on LG. Or is it only on G7? It's a pity you cannot adjust it on any dragonfly model, all ESS dacs offer a wide selection of filters plus custom filters...

 

[soundblast75]

Got mint one for sale, PM if you like, thanks

 

[Chikolad]

I thought you can even select a filter on LG. Or is it only on G7? It's a pity you cannot adjust it on any dragonfly model, all ESS dacs offer a wide selection of filters plus custom filters...

Not on the V20. I didn't even know that option existed.

 

[118900]

I kept my HD600 in a cupboard for years and years because it was so unexciting and undynamic to listen to. Then I got the DFR and, wow that was the first time I started to appreciate the strengths of the HD600!

just goes to show how personal preferences and variables in pairing influence things.

I am always wary when people ask me for my impressions about a "sound" (although I'm also the first to ask the same thing LOL). What sounds like gold to me may sound like rubbish to the person asking. Nothing ever beats listening for yourself and, if possible, borrowing equipment for a few days, especially if its new.

One thing I don't recall from your previous comments, have you tried the DFR with your LCD-i3s? could that give you the sound you are looking for?

 

[drykoke]

What sounds like gold to me may sound like rubbish to the person asking. Nothing ever beats listening for yourself and, if possible, borrowing equipment for a few days, especially if its new.

One thing I don't recall from your previous comments, have you tried the DFR with your LCD-i3s? could that give you the sound you are looking for?

Hi, yes, headphone pairings are particularly personal and there's no substitute for testing it yourself because shape of the head and ear canals can make a huge difference.

Sorry, but I think McCol is the guy with the LCD-i3; I bought my DFC from him on another forum (assuming same person based on username). I would love to have a pair of Audeze to try; I wasn't too happy with Oppo PM-3 planars but perhaps DFR and DFC are more capable than the equipment I previously had.

 

[mantsm]

Is anyone using DFC with Hifiman Ananda headphones? Just wondering what were your experience?

 

[a-LeXx]

I wouldn‘t use a dragonfly with any planars. The problem is, the output buffer is very weak. It can deliver voltage, but not much of a current. Which means, you are very likely to get some audible distortions due to clipping. A DFR/DFC is ok to drive IEMs or efficient dynamic headphones that do not drain much current.