[sarora]

 
That's dramatic. Maybe you should share your findings with John Atkinson from Stereophile, who was unable to measure any differences with/without the Jitterbug.

I checked a bit into it - looks like the JitterBug isn't directly compatible with the C5D. With my MacBook which normally recognizes it natively, the JitterBug causes the audio input to (sometimes) depending on - I suspect power usage - to appear as "Bravo-X Audio" which is the controller inside the DAC/AMP. Most of the time, however, it shows up as IO GENERIC BUS and that's what that output FFT (second graph, first is normal) was, hence the odd pattern and unrecognizable waveform. AudioQuest says this is a known issue on "a few DAC's" -- however, I tried two controller boards that have built in DAC's (my DDJ-SX2 and a Traktor S4 MK2) -- both were not recognized with the JitterBug. I guess anything that requires power at the USB hub gets kicked by the filters in this device. Already don't like the vibe with it because it seems so artificial for a passive device.
 
That second FFT graph (I listened to the output just to see what it'd sound like and it sounded like gargled microphonics) is the result of the IO GENERIC BUS output. They recommend using a powered hub in this case, which I have but have not tried. Nevertheless, from what I can find online, it just seems to be a common-mode choke and maybe a low pass filter; it's sort of suspect with their usage recommendations IMO. I have yet to see any improvement, mainly because my DAC's don't work out of the box with this. But I will plug in my powered hub and see how it goes and re-run the FFT's from the scope.

 

[Mediahound]

FYI- I posted my review/impressions of the Jitterbug here:
 
 
http://www.head-fi.org/products/audioquest-jitterbug-usb-filter/reviews/14053

 

[castleofargh]

 obviously after 2 days you had all the knowledge, understanding and experience needed to write a proper review...

 

[Mediahound]

   obviously after 2 days you had all the knowledge, understanding and experience needed to write a proper review...

After just 2 minutes actually. The difference is noticeable right away when you plug it in, and then when you unplug it. 

 

[Youth]

 
After just 2 minutes actually. The difference is noticeable right away when you plug it in, and then when you unplug it. 

 
Does GMB have external powersupply or is it USB powered?

 

[Mediahound]

   
Does GMB have external powersupply or is it USB powered?

External. According to the Schiit website: " two transformers (one for digital supplies, one for analog supplies) with 8 stages of regulation, including separate local supplies for critical digital and analog sections."

 

[Youth]

 
External. According to the Schiit website: " two transformers (one for digital supplies, one for analog supplies) with 8 stages of regulation, including separate local supplies for critical digital and analog sections."

 
Interesting. I tried it on my Audio-gd DAC 19 which also has external power supply and didn't notice any difference at all.   

 

[zilch0md]

Interesting. I tried it on my Audio-gd DAC 19 which also has external power supply and didn't notice any difference at all.   

I've returned my Jitterbug, but I still believe it could do a lot of good in a system that needs it.

 

[stuartmc]

I've returned my Jitterbug, but I still believe it could do a lot of good in a system that needs it.

Mike, I'm still struggling with the Jitterbug used with the Regen connected with hard adapter to my Tanly USB-DDC.  It does slightly effect the sound, but I'm still not sure it is all good.  It seems to be a little quieter/blacker around and behind images, but this may come at the expense of hearing some of the atmosphere - the subtle higher frequency soundscape cues.  It is difficult to tell if these "cues" are real or a high frequency haze or distortion artifact.   Changes in USB cables seem to dwarf the effect of the Jitterbug and my preferred cable, the Audience AU24, doesn't play well with the Jitterbug at all.  I actually prefer the sound of the Au24 Cable, sans Jitterbug, to the sound of the Supra cable with Jitterbug. I have a Forza Audioworks cable coming that is very similar to the AU24 in construction. I will wait and try the Forza with the Jitterbug before I make a final decision.   Geesh, who  have thought this little device was so finicky.

 

[zilch0md]

  Mike, I'm still struggling with the Jitterbug used with the Regen connected with hard adapter to my Tanly USB-DDC.  It does slightly effect the sound, but I'm still not sure it is all good.  It seems to be a little quieter/blacker around and behind images, but this may come at the expense of hearing some of the atmosphere - the subtle higher frequency soundscape cues.  It is difficult to tell if these "cues" are real or a high frequency haze or distortion artifact.   Changes in USB cables seem to dwarf the effect of the Jitterbug and my preferred cable, the Audience AU24, doesn't play well with the Jitterbug at all.  I actually prefer the sound of the Au24 Cable, sans Jitterbug, to the sound of the Supra cable with Jitterbug. I have a Forza Audioworks cable coming that is very similar to the AU24 in construction. I will wait and try the Forza with the Jitterbug before I make a final decision.   Geesh, who  have thought this little device was so finicky.

 
Hey Stuart,
 
You sound as frustrated as I was. Good for you on being so tenacious with giving it chance to prove itself. 
 
There's a lot to be said for judging a subtle component like the Jitterbug in various combinations with other gear. I tried it "every which way" to no avail. On someone's recommendation, I even tried plugging the Jitterbug into an empty USB port on my TiVo DVR and again, into an available USB port on my smart TV - to no advantage that I could see - despite the other party having seen a big improvement in picture quality. 
 
In the end, at a cost of $50, it wouldn't take much of an improvement to justify keeping the Jitterbug, but everyone who is in the least bit curious should ignore what other people are saying about its efficacy in their systems.  Get a Jitterbug and try it in your own system.  It could actually do some good. Then again, it might not, in which case you can return it or sell it.  It did nothing advantageous for me, no matter where I tried it.  
 
Mike

 

[bikutoru]

If it somehow it does not work in your setup, you forgot to use a drop of: http://goo.gl/App7PI
It will most definitely help! It will help even more if you use a drop in each of your ear or any other part of your body you choose.

 

[conquerator2]

And people say it's not a thing!

 

[Mediahound]

My Jitterbug is going back.
 
While this does seem to improve vocal clarity a bit, I also noticed it slightly decreased overall dynamics and bass impact. If you don't have any issues with your current USB audio, or have another device already such as the Schiit Wyrd which is cleaning up your USB, I would skip this.

On the plus side, if you don't have anything cleaning your USB yet, the cost of entry of this is low so you can see if it makes any improvement for you without too much risk.
 
Overall, it just made the sound a bit unnatural and not necessarily as musical with some types of music such as heavy metal/hard rock. 

 

[DEANO2]

My Jitterbug is going back.

While this does seem to improve vocal clarity a bit, I also noticed it slightly decreased overall dynamics and bass impact. If you don't have any issues with your current USB audio, or have another device already such as the Schiit Wyrd which is cleaning up your USB, I would skip this.


On the plus side, if you don't have anything cleaning your USB yet, the cost of entry of this is low so you can see if it makes any improvement for you without too much risk.

Overall, it just made the sound a bit unnatural and not necessarily as musical with some types of music such as heavy metal/hard rock. 

 

[DEANO2]

So it would cure people from listening to heavy metal music, usually played at insane levels with the resulting hearing loss in later life. That is a good thing, I'll buy two and give one to my 14 year old neighbour. If it stops him playing that garbage at 12 o'clock at night the rest of the neighbourhood will give me a medal.