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D7 Sidewinder....Initial impressions - Page 34

post #496 of 664


 

Quote:
Originally Posted by uelover View Post

It may be curious to question how a peripheral device could draw more power than the source could supply.

 

The USB port could only supply up to 5v (or any other maximum value). So, when the error message says that the USB device is drawing too much power, does it mean that the D7 is drawing more than 5v from a USB port that could only supply up to 5v power?

 

It would only be possible only if the D7 (or any USB device) has the ability to reach into the USB port on our computer and suck out (by an act of force) more power from other components and channel them into the USB port.

 

A better way to make sense off the error message is that the 5V output from our USB port is insufficient to power the D7 fully which might require more than 5V power. Thus, the computer may disable other USB devices just to ensure that a stable 5V of full power is being supplied.

 

But still, that doesn't make sense because all the other devices would still continue to work normally, including the D7.


Actually it has nothing to do with voltage. It is the current that matters. In electricity, power is the product of voltage and current and is given in watts. If the D7 draws 0.5A at 5v, then it uses 2.5 watts. The USB device cannot change the voltage that is supplied to it, but it can pull as much power as it wants. Unless the USB hubs can actively limit the current they transport.

 

USB divides power as "unit load", each having 100mA in USB 2.0. For example, if the D7 draws 500mA, then it uses 5 "unit load". The problem is, any USB device, when originally connected, is given only 1 unit load, or 100mA. It can then ask the root hub for more units and the root hub will allow it more if it can.

 

It's not easy to build a USB device than can manage this properly. To work with only 100mA, the D7 would have to shut down it's amp and as much features as possible. Class A amps are not known for their power efficiency. I don't know if a root usb HUB can actually limit the current it supplies to any given USB device, and I would be very surprised if it did. That said, if the D7 doesn't care about the unit load system and the rule that at start-up, any USB device must draw no more than 100mA, then it might explain why the OS complains that the D7 draws too much power. It shouldn't be a problem, as long as the D7 stays under 0.5 amps.

post #497 of 664
Quote:
Originally Posted by KimLaroux View Post

USB divides power as "unit load", each having 100mA in USB 2.0. For example, if the D7 draws 500mA, then it uses 5 "unit load". The problem is, any USB device, when originally connected, is given only 1 unit load, or 100mA. It can then ask the root hub for more units and the root hub will allow it more if it can.

 

It's not easy to build a USB device than can manage this properly. To work with only 100mA, the D7 would have to shut down it's amp and as much features as possible. Class A amps are not known for their power efficiency. I don't know if a root usb HUB can actually limit the current it supplies to any given USB device, and I would be very surprised if it did. That said, if the D7 doesn't care about the unit load system and the rule that at start-up, any USB device must draw no more than 100mA, then it might explain why the OS complains that the D7 draws too much power. It shouldn't be a problem, as long as the D7 stays under 0.5 amps.


So, is there an assigned upper limit cap at how much current our USB port could output? In order words, will the D7 be able to be so demanding as to instruct the computer to give him more current than what the computer could, thus sucking up current from places other than the USB. If not, then there is no worry about the concern posted by Posam below.

 

This is the gist of what I was trying to ask in my previous post but pardon me for my lack of electronic knowledge. Swap the 'voltage' for 'current' and there's it! =)

 

Quote:
Originally Posted by Posam View Post

This is not one of those USB 3.0 devices and will suck the power out of my laptop causing it to implode (exaggeration)?



 

post #498 of 664


 

Quote:
Originally Posted by uelover View Post

A better way to make sense off the error message is that the 5V output from our USB port is insufficient to power the D7 fully which might require more than 5V power. Thus, the computer may disable other USB devices just to ensure that a stable 5V of full power is being supplied.

 

But still, that doesn't make sense because all the other devices would still continue to work normally, including the D7.


 

Although for me, it does affect the usage of the D7.  I'd say now that when I turn it on and I get the warning, there's a 50/50 chance that it will appear as a usable device.  It always shows-up in the OSX System Information device tree, but half the time it never shows-up as an audio device (for instance, if I Option-click on the volume icon of the Menu Bar, it is never an option, etc).  In all, I'd say roughly 50% of the time it just works without any warning at all, about 25% of the time I get the warning but it still works, and about 25% of the time I get the warning and it never works until I reboot--regardless of whether I turn it off-and-on several times or try a different USB port on a different USB bus (which makes me think more that it's an overall USB system/driver issue, rather than a specific power/bus issue).  It always works after a reboot, though, which at least is fast on a MBA.

 

My ongoing theory is, rather than actual power fluctuations, the OSX USB driver, or its interaction with the XMOS functionality, is simply not properly keeping track of power use and I suspect that sometimes when I turn it off (which is almost always before I close the lid and it goes into sleep mode) it isn't "releasing" that power from its ongoing bookkeeping total for the bus, which is likely done via manual function call rather than an actual power reading.  Kind of like the power equivalent to a memory leak.  I try to wait a minute or so after shutting-off the D7 before closing the lid, but it doesn't seem to make a difference--I think sleep mode in general may mess-up the USB driver sometimes.  The only other device on the bus I normally use is the internal card reader, which for all I know could be disabled when I use the D7--but since I don't have any cards, I never use that reader to know either way, and the System Information utility doesn't seem to indicate whether anything is truly disabled.

 


Edited by bluishgreen - 3/8/12 at 6:58pm
post #499 of 664

Just to add a bit more to this discussion of mA a port can supply more mA than is dictated by the standard, it is the device's job to regulate how much it draws. Just like you can use a 12v 5amp charger on a 12v 1amp device. Going the other way causes problems since the device won't get enough power. I'm glad my gigabyte board has "3x power" usb ports, although the d7 has worked in more than just this pc flawlessly.

post #500 of 664

So is this only an issue with people using the D7 with macbooks? No Windows 7 laptop issues?

post #501 of 664

^ I have no issue with my window 7 laptop

post #502 of 664

Thank you everyone who has posted good information about this device.  I ordered one earlier this week and it reached my home in Seattle, WA in 2 days.  I am really impressed by that shipping speed (why did DVD's from Blockbuster take longer?).

 

It came with 2 usb cables (1 shorty and a long one), a soft bag for transporting the unit in, a warranty card that looks like a credit card and is filled in with information on the back in neat handwritting, and a small bag of screws that appear to be the same as those that secure the front and back plates on the unit.  I can't imagine why those came with it.  Anyone know?

 

Right out of the box it sounded very sharp and clear.  I've been using a Hifiman EF2A, so some of the difference may be tube sound versus solid state, but the Sidewinder just flat out seems to have more detail.  It sounds more...  real.  I am very pleased with it.  It's sounding better the more I listen to it.  I've tried my Grado SR-225's, ThinkSound ts-2's, and some AblePlanet active noise canceling headphones (surprisingly good for the price, but just a fill in until Amazon sends me the Philips Uptowns I've had on order for awhile).  It drove all of them quite well.  It doesn't seem to have as much power as the Hifiman, but it has more than enough.  I'd be concerned about using this for more difficult to drive headphones, but I don't have any to test with, nor have I seen anyone mention trying it with anything like 600 ohm planar magnetics.  I doubt it would have any difficulty with the vast majority of headphones out there.

 

The DAC is simply the best I've heard, in headphones anyway.  This weekend I'm hoping to do some A/B testing with the Sidewinder vs my hometheater pre-amp, the Integra DHC-80.1 vs Oppo BDP-83 through my home theater setup, not headphones.  I'll try hooking the Sidewinder up to the Integra via it's digital output and RCA stereo jacks.  I'll reply back to this thread with my results.  Please forgive me if I don't get around to it though, family comes before hobby.  I'm hoping my sharing the plan stimulates others to try similar comparisons.

 

Integra DAC specs (found here):

Burr-Brown (x6) - 192K / 32-Bit Audio DAC

Vector Linear Shaping Circuitry (VLSC)

32-Bit DSP Chip for Advanced Processing - TI Aureas (x3)

Ultra-Low-Jitter Circuitry to Improve Audio - PLL


Edited by Clayton72 - 3/9/12 at 2:05am
post #503 of 664
Quote:
Originally Posted by Clayton72 View Post

Thank you everyone who has posted good information about this device.  I ordered one earlier this week and it reached my home in Seattle, WA in 2 days.  I am really impressed by that shipping speed (why did DVD's from Blockbuster take longer?).

 

It came with 2 usb cables (1 shorty and a long one), a soft bag for transporting the unit in, a warranty card that looks like a credit card and is filled in with information on the back in neat handwritting, and a small bag of screws that appear to be the same as those that secure the front and back plates on the unit.  I can't imagine why those came with it.  Anyone know?

 

Right out of the box it sounded very sharp and clear.  I've been using a Hifiman EF2A, so some of the difference may be tube sound versus solid state, but the Sidewinder just flat out seems to have more detail.  It sounds more...  real.  I am very pleased with it.  It's sounding better the more I listen to it.  I've tried my Grado SR-225's, ThinkSound ts-2's, and some AblePlanet active noise canceling headphones (surprisingly good for the price, but just a fill in until Amazon sends me the Philips Uptowns I've had on order for awhile).  It drove all of them quite well.  It doesn't seem to have as much power as the Hifiman, but it has more than enough.  I'd be concerned about using this for more difficult to drive headphones, but I don't have any to test with, nor have I seen anyone mention trying it with anything like 600 ohm planar magnetics.  I doubt it would have any difficulty with the vast majority of headphones out there.

 

The DAC is simply the best I've heard, in headphones anyway.  This weekend I'm hoping to do some A/B testing with the Sidewinder vs my hometheater pre-amp, the Integra DHC-80.1 vs Oppo BDP-83 through my home theater setup, not headphones.  I'll try hooking the Sidewinder up to the Integra via it's digital output and RCA stereo jacks.  I'll reply back to this thread with my results.  Please forgive me if I don't get around to it though, family comes before hobby.  I'm hoping my sharing the plan stimulates others to try similar comparisons.

 

Integra DAC specs (found here):

Burr-Brown (x6) - 192K / 32-Bit Audio DAC

Vector Linear Shaping Circuitry (VLSC)

32-Bit DSP Chip for Advanced Processing - TI Aureas (x3)

Ultra-Low-Jitter Circuitry to Improve Audio - PLL



Thanks for posting your impressions

 

So in your opinion it's a step up from the EF2? 

post #504 of 664
Quote:
Originally Posted by djevoultion View Post



Thanks for posting your impressions

 

So in your opinion it's a step up from the EF2? 



The EF2A is only capable of 16-bit sound and I've been ripping my vinyl records at 24-bit / 96kHz in the last couple months.  So yes, it is definately an upgrade.  I'd still recommend the EF2A though, it's a very high-quality device and offers a warm tube sound and may be more capable of handling high ohm / "hard to drive" headphones.  I tried running the line out from the sidewinder through the EF2A's amp and love the softening / warming effect of the tubes, but the sound is more clear when the headphones are driven from the amp in the sidewinder.  All that said, I'll be selling the EF2A and just using the sidewinder from now on.  The crystalline clarity of the sidewinder is more pleasing to my ear than the tube warmth that shaves off the details.

 

post #505 of 664
Quote:
Originally Posted by Clayton72 View Post



The EF2A is only capable of 16-bit sound and I've been ripping my vinyl records at 24-bit / 96kHz in the last couple months.  So yes, it is definately an upgrade.  I'd still recommend the EF2A though, it's a very high-quality device and offers a warm tube sound and may be more capable of handling high ohm / "hard to drive" headphones.  I tried running the line out from the sidewinder through the EF2A's amp and love the softening / warming effect of the tubes, but the sound is more clear when the headphones are driven from the amp in the sidewinder.  All that said, I'll be selling the EF2A and just using the sidewinder from now on.  The crystalline clarity of the sidewinder is more pleasing to my ear than the tube warmth that shaves off the details.

 


I'm Guessing you can't use the EF2A as an amp only or there's not much benefit to combining the two in that way?

 

post #506 of 664

I had a little bit of hassle getting it up and running on Windows 7 but after a some messing around it worked fine.  Now that I have Windows 8 it does not work and I get an error message that says the device is drawing too much power from the USB port.  I'm hoping to fix this with a powered USB hub. 

post #507 of 664

@the power problem on macs. did anyone tried to measure if the mac's usb indeed giving  power as per standard usb specifications?
 

Quote:
Originally Posted by Posam View Post

So is this only an issue with people using the D7 with macbooks? No Windows 7 laptop issues?


so far never see a problem with Win7 or even XP.

 



Quote:
Originally Posted by Clayton72 View Post

It came with 2 usb cables (1 shorty and a long one), a soft bag for transporting the unit in, a warranty card that looks like a credit card and is filled in with information on the back in neat handwritting, and a small bag of screws that appear to be the same as those that secure the front and back plates on the unit.  I can't imagine why those came with it.  Anyone know?

 


iirc, those screws is there because some the product before D7 have interchangeable opamp or batteries. thus people often lose or break their screws when they opening an closing the case and complain to ibasso. and now most of the product come with spare screws I think.

 

post #508 of 664

I want to apologize in advance if this issue has been clarified at some earlier point in this thread, but at 35 pages, I'm frankly just going to hope someone answers.

 

Ordered the D7 on a Thursday in NY, got it on Monday, so major kudos to iBasso.  Anyone wavering over the $22 shipping fee, please don't, it's worth it.

 

Right, driver downloaded off of iBasso's site, promptly installed, no issue.

 

I listen to a few tracks at various bitrates to break this suave little bugger in; 24/88, 24/96, no problem.  Great!

 

Off I go to HDtracks to celebrate the entry of my new toy into the home.  I buy The Rolling Stones Hot Rocks at 24-bit/176kHz, fire it up, aaaaaaand...no sound.

 

NO SOUND?!?! *#*#!!*%! 

 

Why, oh why??

 

Mediamonkey set to WASAPI Output, Windows 7 x64 set to output at maximum 24/192kHz, so the system recognizes the DAC's capability.


Edited by oneway23 - 3/10/12 at 2:55pm
post #509 of 664

D7 Doesn't support 176 sample rate on OS X either. When I enquired of iBasso, they said:

 

 

Hi,
I think this only can be answer by the driver supplier, Thesycon.
We dont know the reason as well. Sorry about this.
 
Sincerely
iBasso Audio

Quote:
Originally Posted by oneway23 View Post

I want to apologize in advance if this issue has been clarified at some earlier point in this thread, but at 35 pages, I'm frankly just going to hope someone answers.

 

Ordered the D7 on a Thursday in NY, got it on Monday, so major kudos to iBasso.  Anyone wavering over the $22 shipping fee, please don't, it's worth it.

 

Right, driver downloaded off of iBasso's site, promptly installed, no issue.

 

I listen to a few tracks at various bitrates to break this suave little bugger in; 24/88, 24/96, no problem.  Great!

 

Off I go to HDtracks to celebrate the entry of my new toy into the home.  I buy The Rolling Stones Hot Rocks at 24-bit/176kHz, fire it up, aaaaaaand...no sound.

 

NO SOUND?!?! *#*#!!*%! 

 

Why, oh why??

 

Mediamonkey set to WASAPI Output, Windows 7 x64 set to output at maximum 24/192kHz, so the system recognizes the DAC's capability.



 

post #510 of 664

Thanks for the prompt reply...Man, that really does stink.

 

I don't understand the issue at all.  I mean, both the operating system and the media player display 24/176 as a viable option, and the D7 itself lights up to indicate signal reception.

 

 

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