UpTone Audio USB REGEN

Device Type: USB Signal Regenerator
Input: USB Type-B
Output: USB Type-A
Dimensions: 57 x 46 x 18mm
Weight: 1.8 ounces (52 grams)
Availability: Direct Online
Price: $175.00
Website: uptoneaudio.com

REGENerator
Unlike the AudioQuest JitterBug we looked at last week (see review) that plugs into your computer, the USB REGEN is designed to be placed at the other end of your USB cable, between it and your DAC. Where the REGEN also differentiates itself from the JitterBug (and others) is the guys from UpTone Audio are completely REGENerateing the data, delivering a cleaned up impedance matched signal to your DAC.

image credit: UpTone Audio

I'm going to let UpTone Audio explain the REGEN in detail (get comfy):

To explain how the UpTone Audio USB REGEN works and why it is so effective with such a wide range of USB input DACs, we first need to define some technical terms and some problems inherent in USB audio interfaces—hopefully in not-too-technical language:
PHY: PHY is an abbreviation for the electronics that interface to the physical bus. PHYs exist in most every type of data interface (Ethernet, FireWire, optical, etc.) A USB PHY serves two primary functions: to convert the analog voltages used on the Data-plus and Data-minus wires into a digital format normal logic can understand, and to convert the high speed one-bit-at-a-time serial data stream into a slower parallel set of wires to be sent to the USB protocol engine (XMOS processor, FPGA with USB core, etc.). The lowly PHY chip is actually a tremendously noisy and complicated device containing multiple PLLs and clocking at various phases—and there is no such thing as an optimized-for-audio PHY. The PHY part of a DAC’s USB is highly susceptible to the condition of the USB signal, its "Signal Integrity" (SI).

SIGNAL INTEGRITY: A high-speed USB signal runs at 480 mega bits per second, which is fairly high. SI is comprised of the rise/fall times of the signal edges, amplitude of the signal, noise sitting on top of the signal and jitter of the edges. Variations in any or all of these can decrease the SI. The computer determines this initially, and then it can get significantly degraded by running through cables and connectors.

The decrease in SI can be so large that it becomes difficult for the PHY to determine the actual bits. Thus the PHY contains several methods used to pre-process the analog signals in order to make it easier to determine the bits. When the SI is very good, the PHY can turn off the pre-processing steps and easily determine the bits. As the SI degrades the PHY turns on different parts of the pre-processing as needed. Each of these steps takes a fair amount of power to operate, thus creating noise on the power and ground planes. The more processing the PHY needs to use to determine the bits, the more noise is generated. Thus part of the packet noise is directly related to the signal integrity of the incoming signal. The higher the SI, the lower the noise.

PACKET NOISE: In a DAC the data packets coming in on the USB bus are not continuous—there is significant time in-between each packet. Thus the processing of these packets produces noise on the power supply and ground plane that come in bursts, and we refer to this as "packet noise". Since the rate of USB packets is 8KHz there are strong components of this noise in the audio band. This noise can cause jitter in clock oscillators, re-clocking flops, and DAC chips. It can also go directly into noise on the output of DAC chips.

Part of this noise is determined by the USB protocol engine (chip after the PHY) and is going to be constant for a particular DAC.

POWER DELIVERY NETWORK (PDN): In order for a power supply to properly respond to instantaneous load variations, it needs to have a low impedance over a very broad range of frequencies. For digital audio this is from low Hz to hundreds of Mhz range. The entire supply flow from mains AC to board layout and capacitors on the board play a role in getting this right. The process of frequency optimizing the PDN is something that is done in expensive high-speed network equipment, but is almost never done in consumer products, especially audio equipment. (And our experience with the REGEN points to this being quite important for digital audio.)

Okay, now that some definitions and issues have been set forth, let’s look at how the UpTone Audio USB REGEN addresses them.

To recap the issue:

The lower the signal integrity (SI), the harder the PHY has to work, which produces greater packet noise. If the SI is very good, the packet noise from the PHY is less than that from the protocol engine. As the SI degrades the packet noise from the PHY can dominate.

Again, the packet noise consists of two parts: noise from the USB protocol engine and from the USB PHY. The protocol engine noise does not depend on the input signal quality, just the data, so its impact is always going to be the same no matter what is done with the input. The PHY is the part that actually connects to the electrical signals on the bus, ITS contribution to packet noise IS dependent on the quality of the input signal.

It is very important to keep in mind that all this is what happens INSIDE the DAC by its own operation, it is NOT noise on the USB bus that is somehow getting into the DAC as is commonly thought.

At this point there aren't any DACs that have been specifically optimizing their USB inputs for SI and impedance match, it's too new as a specific concept to design to. But the best DACs do optimize this to some degree, whether by trial and listening or as a byproduct of optimizing for something else.

So tell us how the darn thing works already!:

The REGEN is at its core a single-port USB 2.0 hub. All hubs actually contain two USB interfaces and a full-blown USB protocol engine. It is not just working at the analog level, it is actually receiving the data from the DAC, putting it in a buffer and retransmitting (and the other way for the packets from the DAC).

It uses a selected USB hub chip to create a new USB stream to deliver a very high signal integrity to the DAC's USB PHY, thus decreasing the PHY’s contribution to packet noise. It is called “REGEN” since it completely REGENerates the data signals that cables are messing up—it’s not just a re-clocking. Because it uses clean power and a low jitter clock, the output of the hub has low noise and low jitter. To be most effective, and to maintain best signal integrity and ideal impedance matching it is best positioned right at the input to the DAC, thus its small size, low weight, and included male>male USB ‘A’>’B’ adaptor.

The result is that the PHY in the DAC doesn't have to use any of its pre-processing circuit arsenal so the packet noise is as low as it is going to get.

Does the REGEN eliminate the need for a good USB cable and other computer optimizations?:

No. The hub chip inside the REGEN has its own PHYs and protocol engine, which themselves generate packet noise on ITS power and ground planes. So the REGEN itself is also sensitive to the SI of the signal fed to it, which is why good USB cables and specialty USB host boards feeding it still make a difference—maybe just not as much. A lot of time was spent on the design and board layout to minimize this packet noise but it is still there. The impedance of the "Power Delivery Network" (PDN) over a broad range of frequencies determines the amplitude of the packet noise produced by the hub chip. The REGEN’s frequency optimized PDN is what makes it such a good sounding source.

The ideal solution would be to figure out how to prevent all this noise from crossing out of the USB input system and getting into the DAC chip and clock. Unfortunately this is really tough and nobody has completely figured out yet how to do so. Thus every DAC ever built will have some level of susceptibility to external influences, some more some less.

The question everybody asks then is:

Well what about DACs that have full galvanic isolation after the USB system and reclocking on the DAC side? Unfortunately USB input noise of all sorts still makes it through to some extent and reaches the DAC master clock. Exactly how this works is complicated, John Swenson has written in-depth about this elsewhere [see Part 2 of our Q&A with John]. The upshot is that neither galvanic isolation nor re-clocking completely get rid of it. They help attenuate it some, but don't get rid of it.

The REGEN’s secondary function is to ignore the 5V USB bus power coming down the cable from the computer (or other host) and to provide—to DACs that require it—a very clean and isolated 5V supply. The REGEN has a separate ultra-low-noise regulator for this. (For DACs that don't use the 5V wire, that regulator in the REGEN is not used for anything.)

Lastly (unlike another hub-chip based device out there), the UpTone REGEN uses a 4- layer board, primarily to allow a proper impedance match. With a standard thickness 2- layer board it is impossible to attain a proper impedance match to the hub chip. The pins on the chip are small and close together, this necessitates very thin board traces. With a two layer board the distance between ground plane and these traces (this is called a differential micro-strip configuration) produce an impedance that is much greater than the spec. With a 4-layer board the ground plane can be much closer to the top layer, and that allows for appropriate impedance with the very narrow traces. The REGEN also uses surface-mount USB jacks that allow for appropriate trace width and spacing to continue the impedance matching through to the USB jacks. The result of this is that there will be very minimal reflections at the REGEN side. Even if the DAC does not have good impedance matching—which is pretty common and which WILL cause a reflection at the DAC end— it will be absorbed at the REGEN because of the proper impedance matching.

On to the review!

As you can see, the REGEN is a small black aluminum-covered device with rounded sides about the same size as one and half Zippo lighters. On the input side resides a USB Type-B port which is where you plug in your USB cable of choice from your music server/computer, and on the other end is a USB Type-A output where you can connect the included (and recommended) male/male USB A/B solid adapter plug or the included 6" male/male USB A/B cable. You can obviously also roll your own. On the input side resides a 5.5mm x 2.1mm barrel jack for the included Mean Well 7.5 volt / 22 watt SMPS which plugs into your wall outlet with an included, detachable, 18" Volex power cord.

Some people have experimented with switching out that SMPS with a linear power supply ("...in the range of 6-9V/1.5A is fine; or even 12V if you are certain that your DAC is not deriving much power from USB bus") over on Computer Audiophile and report positive sonic results. I happen to have the LH Labs LPS4 linear power supply here along with the REGEN so I'll talk about that pairing shortly.

I'm going to run the same scenarios I used for the JitterBug reviews using both the Lampizator Lite-7 DAC and the Auralic Vega in my main system, as well as the Audeze Deckard in my desktop system (system details can be found below in the Associated Equipment link).

Let's REGEN USB!
I ran through my usual routine of sticking the REGEN into my system upon its arrival and just listening to music for a few weeks. Most of this time saw the Lampizator in action converting my bits to music. When it came time to take the REGEN out, I was listening to Omar Souleyman's latest scorching soulful burner Bahdeni Nami streaming from Tidal through Roon. Wow! Is it really going to be this obvious?

Yes, it is. Souleyman is joined on Bahdeni Nami by saz player Khaled Youssef and Rizan Said on keyboards. The saz, or bağlama, is a stringed instrument resembling a lute and it's got a very unique sound. Said's keyboards are overdriven and raw. When I removed the REGEN, hit play, and sat back down to listen, everything sounded as if it had just come back from a week at weight loss camp. Really? Is it going to be that easy?

Yes, it is. The REGEN's affect on the system with the Lampizator DAC most noticeably was an increase in the music's weight—bass response improved and the midrange sounded richer adding up to something akin to a loudness control (if you can remember back to those days). Only cleaner.

Let's move on to the Auralic Vega. REGEN in, the same results as with the Lampizator. Another improvement with the REGEN in was an increase in image focus and an opening up of the overall sound picture. If I were to rate these changes on a scale of sonic amount of 1 to 100, where 100 is buying a new pair of speakers, I'd rate the REGEN around a 20. I also want to stress that using the REGEN does not change the overall character of my system, rather it enhances and improves existing qualities.

This is an important distinction, especially when building a hi-fi. Let's say you have $500 to spend on a DAC. I would recommend finding the DAC you enjoy most in your system, even if that DAC costs $500, and live happily ever after. As one's DAC budget increases, I wouldn't change this approach—buy the DAC you enjoy most and live happily after.

If, and in the land of audiophiles "if" is usually "when", you have your system sorted and you'd like to see if you can squeeze some more performance out of it, my experience says the REGEN offers an incremental improvement that's worth the asking price. YMMV. Sermon, over.

Fitting the REGEN into my desktop setup using the review sample Audeze Deckard DAC/Headphone amp, I immediately heard a more refined sound from Johnny Cash's American Recordings. His voice had more weight and there was also a sense of less of what I'd call digital hash surrounding the sound. Perhaps the best way to describe the sound of my desktop system with the REGEN out of the picture was a thinner less engaging sound. This difference became even more evident over time. REGEN in; better. REGEN out; worse. Simple.

Through the wonderful Audeze LCD-X 'phones powered by the Deckard, I heard the same improvement in terms of refinement; music sounded fuller, clearer, and more natural. Of course the improvement in spatial queues I mentioned with the REGEN in my main system were not applicable here since the room is longer in the picture. This also applies to my desktop system where this same sonic improvement relating to the overall sound image was not as dramatically improved as compared to my main system. My desktop listening is very much of the nearfield variety so I do not get the same sense of physical space here as I do in-room. I often wonder why some people feel they can easily translate a review using speakers in a room to listening through headphones and expect that all of the traits described will cross over. That's not the case in my experience.

Last but not least, I put the REGEN back in my main system coupled to the Lampizator DAC and instead of powering the REGEN from the included SMPS, I powered it from the LH Labs LPS4 linear power supply. I noted a subtle difference mainly in spatial presentation with improved image stability and an increased dimensional quality to the sound picture. While I certainly would not recommend spending the LPS4's $799 asking price, you can certainly explore less expensive options if want to eek even more out of your USB playback. Me? I'd leave the REGEN as is.

REGEN'd
The Uptone Audio USB REGEN improved the sound of both of my systems through three different DACs. I found the REGEN consistently added greater weight, clarity, and refinement to my music reproduction which led to a more musically engaging experience. The greatest benefit came through my main system, listening in-room, where the music has a chance to breath in real space. The REGEN adds a more natural voice to that breath which is a very welcome improvement in my book.


Associated Equipment

COMMENTS
DH's picture

I'm one of the early adopters - I had faith in the product based on knowing Alex and John via Internet fora.

With my Mytek 192 DSD DAC, the Regen made a noticeable positive impact. The USB SQ was - for the first time - better than the SQ when using Firewire. In previous setups - even using other devices for improving USB sound - the USB SQ had, at best, equalled FW, but had never surpassed it. Now it does.

I think Michael put it well in the review: the Regen doesn't change the character of the sound, it just improves it in all sorts of small, but audible ways. Definitely worth the relatively low price.

Cohnaudio's picture

DH, did you have a problem when you used the Regen with the Mytek? When I plugged it into the Mytek, I got some messages re the drivers and the Mytek stopped recognizing the JRMC. It just say no lock. Do you use JMRC? I tried redoing the drivers, but that didn't work. I think it changed something in JRMC, but I can't figure out what. Any help would be most appreciated

DH's picture

You can't hotswap USB items connected to the Mytek. If you don't have recognition/signal, then turn off the Mytek, remove the Regen completely from the Mytek USB port, turn the Mytek back on, and only after the Mytek boots up - re-attach the Regen.
The Regen is essentially a specialized USB hub, but it meets spec. No reason the Mytek shouldn't work with it.

andrasszamek's picture

Thanks for the review Michael! What happens when you combine this with the jitterbug? or with the totaldac cable? is that something one would want to do? there are so many options, my head spins. :)

Michael Lavorgna's picture
I've decided to approach these reviews individually first, the Schiit Wyrd is next, and then write a separate article talking about the various combinations. It seemed to be the best way to keep from confusing things.

I also have the totaldac USB filter/cable here so I'll throw that into the mix as well. While I have not tried the totaldac cable with any of the other devices yet, I would think it best to steer clear of using two filters, i.e. the totaldac cable + JitterBug. We shall see.

andrasszamek's picture

awesome, thank you!

maelob's picture

Similar question on my side, wonder if I could combine it with a Wyrd. I guess we will have to wait for your review. Great review, I am all about improving a system for little money.

fmak's picture

My Wyrd packed up after a couple of months. Emailing Wyrd with serial no produced no response, even though it was bought direct from them.

My sample also had a defective screw and very sharp corners that cut through skin.

Disappointing.

DH's picture

And it improved SQ a bit more. Stopped using the Wyrd b/c I didn't want so much cabling involved in my small space.
It's also reported that the Regen in combination with a specialist PC USB card like the SOtM, PPA or the JCat is even better.
The explanation is that feeding the PHY of the Regen itself a clean, quiet signal reduces the "self-noise" of the Regen.

fmak's picture

results! This may shed some light on what the important parameters are?

It will also be useful to assess the effect of the usb cable.

Frank Hardly's picture

Nice review. I particularly appreciated your scale of magnitude assessment- ie speakers equaling 100. I didn't notice a similar evaluation of the jitterbug... Any thoughts on this?

Michael Lavorgna's picture
...in the final write up where I'll focus on the comparisons. I will say that there will be a point spread between using one or two JitterBugs in my MacBook and iMac ;-)
GLP's picture

Just wondering your thoughts and comparison of these two products that you just reviewed? I know they are different in what they do, just wondering the difference in sound quality.

Thanks, Gary

Michael Lavorgna's picture
I'm going to get into comparisons in the last article. Since I'm reviewing three devices (JitterBug, REGEN, Wyrd), and now adding a fourth (totaldac USB cable/filter) into the mix, it makes sense to take them one a time and do a roundup at the end.
mcullinan's picture

I like to know, is the effect cumulative, does the region have more of an effect and you could forgo the others. Whats the best value?

2_channel_ears's picture

...the means to connect at the 'Regen' side? Or do you need to get a cable or adapter to put it in the altogether?

Michael Lavorgna's picture
...the USB cable that goes between your computer and the REGEN. From the REGEN to your DAC, UpTone has you covered.
2_channel_ears's picture

..more closely. But riddle me this naturally audiophile question. Are there any similar products worth considering?

Michael Lavorgna's picture
I just reviewed the AudioQuest JitterBug, I provided a link to my review in the first paragraph here, which addresses some of the same issues. I'm also in the process of reviewing the Schiit Wyrd which addresses similar issues albeit in a different manner.

I also have the totaldac USB cable/filter which I'll be talking about in my wrap up on all of these devices.

So the answer to your question is a resounding yes!

akeg's picture

Hi Michael,

I have talked to Alex Crespi at Uptone Audio and he advices that the supplied extension USB cable is not the best cable. Do you (or any one else reading this) have a suggestion for a short extension cable of very high quality that I can use instead?

Venere 2's picture
Venere 2's picture

Just plug the solid USB A/B adapter you get with the Regen into the Dragontail. The Dragontail is about 4 inches long and is a mini Carbon USB cable.

akeg's picture

Thank for your reply. However, I think the Dragontail is A/A. If so, it will only work between the computer and the Regen, but I need the extension between the Regen and the dac, i.e. a male/male A/B.

Venere 2's picture

You can plug the included Regen USB A/B adaptor onto the Dragontail. That way you have USB cable-Regen-Dragontail- Regen USB A/B adaptor (the hard one, not the cable).

akeg's picture

Yes, that's correct. Thanks. It would be interesting, however, to know the effect of introducing one extra link (including two extra connectors) in the signal chain from the Regen to the dac compared to running only a very short, very high performing USB A/B cable.

akeg's picture

Hi,

I will not be able to fit the REGEN to my DAC using the solid adapter and since I will be using a very good USB cable (Audioquest Diamond) from the computer to the REGEN, it seems like good idea to have an extension cable of similar quality between the REGEN and the DAC. I therefore talked to JPLAY and they agreed to make a 6-inch JCAT USB cable using the double-shielded connectors they have on their dual-lead Reference USB cable.

hifial's picture

in my system was better then each alone.
I had used the Totaldac usb cacble before I got my Regen. I tried them separately and each made its own worthwhile improvement but together the they made more of an improvement then either alone. I love what my Regen does for the sound in my system. As a reference my system besides the above: exaSound DAC>Merrill Audio Veritas Amps>B&W 802D Speakers.

I have a friend who uses his Regen with his top of the line Synergistic Research USB cable with the same outcome as mine above.

YMMV

Michael, I will be looking foreword to the combined review.

PS Michael, you must try Uptone Audio's Mac Mini fan/power supply kit with their JS-2 power supply. Really worthwhile, not a subtle improvement.

judmarc's picture

I was one of the purchasers who got an early version of the Regen (called Green for the color of its LED light; the second, current version is called Amber for similar reasons), then updated to the current version courtesy of a low cost upgrade program provided by UpTone. This left me with an Amber Regen and the bare circuit board from the Green Regen. So I plugged the latter into the aforementioned into my DAC, and now I can't get the smile off my face.

Michael Lavorgna's picture
Very interesting. I'll be digging into the various combos this week. But I only can REGEN once ;-)

Cheers.

grawhi80's picture

Have you tried this or the Jitterbug attached to a streamer on media player such as the Auralic Aries or Aurender device? Does this give the same sort of gains?

mlgrado's picture

I think I am already benefiting from something similar. I am using a corning optical USB. It takes the regular USB signal, converts to optical, then at the other end 'regenerates' a standard USB signal from the optical signal. Idea is to isolate from the computer USB bus. Yes, you still have the 5v power to deal with, but I am injecting clean(er) power with an iFi iUSB before the Corning cable, so ideally the Corning is being run on clean power.

hmasoni's picture

Can you comment on efficacy of using the REGEN between the Computer and a USB-XX converter??

foreverzer0's picture

Hi MIchael,

I also have the Regen on order and also have a LPS4.

Were the power connectors from the LPS4 compatible with the Regen? Also, did you use the 12V with no issues?

Thanks,
Edward

Michael Lavorgna's picture
The LPS4 connectors are compatible with the REGEN. I'll refer you to UpTone's Questions and Answers page for more info on using the LPS4 with the REGEN.
Chad Hord's picture

The product looks great. The article seems clear and technically sound. Yet the question I keep asking myself is, why isn't the goal to start with a better source than an on-board USB port. Like a PCI card that's been designed to send a better USB source. Products like this seem great, but I hate the idea that I am just buying a USB band-aid.

louisxiawei's picture

what do you think a combination of an aduiophile PCIe card (e.g. SOtM's hub/PCIe card) and Uptone regen will have any significantly big difference from using Uptone regen alone from the stock motherboard? Since Uptone aims to minimize the difference between different PC configurations. I might assume that the merit of your PCIe card or USB hub will be somehow diminished if using together with Uptone regen like product.

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