First off, under most circumstances, there is pretty much zero technical merit to regenerating a USB signal in some special way. The USB audio signal is a sort of "packetized signal" - which, for the non-technically oriented, means that the audio is sent in little chunks, which are then reassembled into a continuous data stream in the DAC. The USB interface in the DAC does the job of regenerating the data stream, and most of them do a pretty good job these days (ours certainly do), and, if the DAC is doing its job correctly, then it ignores slight variations in when the packets arrive and other similar "anomalies". (Strictly speaking, with an asynchronous USB connection, the DAC controls the majority of the timing rather than the sending device, then it ignores any small variations that remain.) Incidentally, all USB hubs, even the $10 ones, "regenerate the signal" - and do so to meet USB spec - they're just claiming that their $175 one somehow "does it
better". Since many DACs do "lock onto then incoming data", at least to some degree, it's possible that some few DACs do their job so badly that providing them with a "cleaner" USB signal might improve their sound, but they are in the minority these days.
Second, the "jitterbug" is
NOT a regenerator, and doesn't claim to be; it is simply a
FILTER, which is claimed to both remove noise from the USB data lines themselves, and from the power lines that are part of the USB signal (a USB-powered DAC, like our Egos, gets both its signal and its power from the USB connector). This puts the JitterBug in the same class of usefulness as a power line filter; it probably won't hurt anything, and it might even occasionally help, but I wouldn't
assume that it will make any audible difference.
Many audiophiles don't seem to understand some things about basic electronic theory. Devices like noise filters are designed to
ELIMINATE SPECIFIC PROBLEMS. If you actually have a noise problem, then a noise filter is an excellent way to solve it. However. most noise problems are in fact audible; while it's possible that you may have some subtle degradation of audio quality due to some interaction between the audio signal and some mysterious noise that isn't itself audible, like ultrasonic or RF interference, it really isn't that common. Not surprisingly, even though the various types of noise filters sold by many companies may do an excellent job of eliminating noise
IF YOU HAVE A NOISE PROBLEM, they would very much like you to believe that, even if you don't hear any problem, you should still purchase their product to reduce or eliminate some rather more subtle problem anyway. (It's sort of like someone trying to sell you "low flicker light bulbs" because, even though you don't notice your current bulbs flickering, they're still producing enough flickering you can't see to give you a headache. There may in fact be some truth to their claim..... or maybe not.)
It has been my personal experience that
SOME USB powered DACs are very sensitive to power supply noise (and so they will actually make odd little chittering noises in the background when there's no music playing). In that case, I would agree that the noise would audibly degrade the listening experience. I've even heard a few where you could actually "hear" when you opened and closed Windows on your computer screen as a change in the noises coming from your speakers. This will vary depending on the DAC itself, and on how noisy the power source on your computer is, and on how you have things connected together. (I haven't noticed this with our Egos on any computer I've tried them with, and I've never noticed it with any AC wall powered DACs I've used... but I can't rule it out.)
However, my point is that,
IF you have this sort of noise happening, then it's
POSSIBLE that something like a JitterBug might help reduce or eliminate it. Or it may not, in which case you may need to move up to a real USB isolator. Likewise,
IF you have a DAC, especially an older one, or one with an unusual design, which is unusually sensitive to USB packet timing, then something like the USB Regen
MIGHT make it perform (and sound) better. However, as you've probably noticed, there are a lot of IFs and MAYBEs there... so, unless you're the kind of person who buys volcano insurance, I would strongly suggest putting your expectations of an improvement on the shelf, and testing it yourself, on your system (with
NEUTRAL expectations firmly in place), before spending any money. And, please, keep it firmly in mind that, even if such a device actually did improve the sound of some other system, it may or mat not improve
YOURS. (And any claim that such a device will "improve the sound of any system" is an egregious exaggeration.)
And, please, keep in mind that, while it's certainly possible that "your system doesn't have the resolving power to detect the difference", or that "your ears aren't good enough", or even that "your source material isn't good enough quality for it to matter", it's also quite possible that it simply really doesn't make any difference - either because it's actually pure snake oil, or because it does solve a real problem that your system simply doesn't have.
I bought an Audioquest Jitterbug but ended up returning it after a week because I just could not notice any improvement or difference. I assumed that either my system did not have the resolvng power to warrant a USB regeneration component, my ears are not capable of detecting the improvement or there's just not much noise in my data chain.
