Another new USB regenerator: Lightspeed Revive

[audioarcher]

Received my Revive today in the mail today. It was easy to install. I plugged the charge cable into my Teradac U9 linear power supply, which has a USB A connector on the back. Then connected the supplied USB A to C cable from the computer to the Revive. Next I connected my Lightspeed USB cable from the Revive to my ( exaSound e20 mk III with femto clock ) DAC.

I am very impressed with the sound! There is more focus and a deeper soundstage than before. Also a lower noise floor. I was using the Uptone Audio Regen and two Audioquest Jitterbugs before I got the Revive, and the Revive is much better using the same linear power supply! Highly recommended.

 

I will post more impressions when I get more time on it.

 

Sean

 

 

[johndoe21ro]

Received my Revive today in the mail today. It was easy to install. I plugged the charge cable into my Teradac U9 linear power supply, which has a USB A connector on the back. Then connected the supplied USB A to C cable from the computer to the Revive. Next I connected my Lightspeed USB cable from the Revive to my ( exaSound e20 mk III with femto clock ) DAC.

I am very impressed with the sound! There is more focus and a deeper soundstage than before. Also a lower noise floor. I was using the Uptone Audio Regen and two Audioquest Jitterbugs before I got the Revive, and the Revive is much better using the same linear power supply! Highly recommended.

 

I will post more impressions when I get more time on it.

 

Sean

 

 

 

Hi, Sean! Make sure you keep your promise!

[uncola]

I'm very impressed with my revive too, powering it with external regulated LPS. Much more noticeable improvement than using my schiit wyrd

 

Personal comment removed - Editor

[esimms86]

learn to read tone you autist

 

Very witty. And socially tone deaf. I hope that no one, even making a poorly considered and crude joke, ever refers to you by name as a "has been" on a public forum where you have a professional reputation. No need to respond as, after 7 years on this forum, you are the first person here to make my Ignore List.

[marce]

I am amazed at the rhetoric surrounding what are basic USB hubs and the magic they seem to perform... I would like to see some decent information such as eye diagram etc...

Gavlanic Isolation...

https://en.wikipedia.org/wiki/Galvanic_isolation

 

Unless the layout is done very carefully with extra filtering then galvanic isolation does NOT stop noise, noise will still couple through. none of the layouts I have seen so far show this concern. Again without data you don't know whether your USB output is that bad...

 

Impedance matching... LOL the USB guidelines state all USB to be 90 ohm diff pair routed, nothing special and most if not all layouts follow the guidelines...

 

Signal Integrity, show me plots and data that show this is greatly improved and that the signal before was so bad...

This proliferation of USB hubs (the same chips can be found in many self powered USB hubs that are no different, just don.t have pages of rhetoric to market them) has come as no surprise as more manufacturers jump on the cash cow that has been created, unnecessarily.

[YashN]

OK, I ordered one to compare the Regen and Schitt Wyrd.

 

It would be interesting to compare to the corresponding iFi device and Intona, Mutec devices (if at all possible).

[YashN]

Signal Integrity, show me plots and data that show this is greatly improved and that the signal before was so bad....

 

Why don't you do some plots and data gathering yourself instead of asking other, Marce?

[johndoe21ro]

Why don't you do some plots and data gathering yourself instead of asking other, Marce?

 

That would be a good idea!

[marce]

Why don't you do some plots and data gathering yourself instead of asking other, Marce?

 

 

I see the data for USB hubs etc regularly, covered by NDA's... Its not me blindly using them though and to be truthful an honest manufacturer would bombard you with graphs and data if they showed anything... i do believe one producer said they didn't have the equipment to do certain measurements!!! It aint me making the super claims about a product with no supporting data, just saying.

Oh one thing about impedance matching for digital signals, even if the USB hub has correctly done 90 ohm diff pair traces, any other device with incorrect routing will cause an impedance mismatch.

[mmerrill99]

It seems to me that the critics of these USB hub devices cite lack of measurements in support of their criticism. But what is their argument exactly? Is it that these USB hubs don't improve USB audio as is reported by many? Is it that these USB hubs are no different to the non-audiophile USB hubs sold in the computer marketplace? Or is it that they see that the inability of existing measurement to show this audible improvement is upsetting their objectivist stance?

 

Nothing wrong with being sceptical.

[marce]

It seems to me that the critics of these USB hub devices cite lack of measurements in support of their criticism. But what is their argument exactly? Is it that these USB hubs don't improve USB audio as is reported by many? Is it that these USB hubs are no different to the non-audiophile USB hubs sold in the computer marketplace? Or is it that they see that the inability of existing measurement to show this audible improvement is upsetting their objectivist stance?

 

Nothing wrong with being sceptical.

 

 

 

In my opinion they are not required in most cases if not all...

No measurements of USB interfaces before the devices is used or after just rhetoric... A chance to make money has been seen and everyone is now jumping on the bandwagon, the measurements I have seen say they do nothing and nothing I have heard has either.

And we are talking about digital data here...

[mmerrill99]

In my opinion they are not required in most cases if not all...

No measurements of USB interfaces before the devices is used or after just rhetoric... A chance to make money has been seen and everyone is now jumping on the bandwagon, the measurements I have seen say they do nothing and nothing I have heard has either.

And we are talking about digital data here...

"Nothing wrong with being sceptical." but being cynical is a different matter

 

What have you listened to? On what systems?

What digital data are you talking about?

[marce]

The USB data stream that goes to the DAC its digital data in packets so it is read or it isn't read and USB interfaces are pretty solid so the data is going to get through so account for the difference you percieve....

[mmerrill99]

The USB data stream that goes to the DAC its digital data in packets so it is read or it isn't read and USB interfaces are pretty solid so the data is going to get through so account for the difference you percieve....

Why does this statement come up every time these & similar digital audio devices are discussed as if it hadn't been explained a hundred & one times already on this forum?

 

Please read Swensons' & others premise for the operation of these devices & the difficulty in measuring the differences before rehashing the same discussion yet again!

[marce]

Don't talk daft man I spend all day getting digital signals from a to b and we don't get hung up on all the BS sprouted. have to read the stuff put up there, already read and dismissed a lot of it, just do the job properly, that includes measurements, its you who is rehashing the same defences, provide evidence, convert on sceptic by true facts and figures then, instead of anecdotal evidence based on easily fooled perceptions. Read plenty of the stuff put up there, a very strong audiophile bias and a hint of BS, but then you have to promote a product you are selling.

It is digital data, what else could it be herds of elephants carrying packages of data on their backs.

Why don't you stop pushing the audiophile biased stuff and look up and learn the true facts. If you are going to design a USB hub or even copying the circuit for the EVB-USB2412 you could at least measure and produce evidence (or just to help through the design cycle). There is nothing hard to measure, the digital data, look for noise before and after, what else.

Stop fooling yourself over a basic digital transport system, that's all it is, these are basic USB hubs that's all, nothing special and USB data is digital as is a lot of data these days, not rocket science.

There is nothing special about this, why don,t you try a basic USB hub you'll get the same benefits.

[mmerrill99]

Don't talk daft man I spend all day getting digital signals from a to b and we don't get hung up on all the BS sprouted. have to read the stuff put up there, already read and dismissed a lot of it, just do the job properly, that includes measurements, its you who is rehashing the same defences, provide evidence, convert on sceptic by true facts and figures then, instead of anecdotal evidence based on easily fooled perceptions. Read plenty of the stuff put up there, a very strong audiophile bias and a hint of BS, but then you have to promote a product you are selling.

It is digital data, what else could it be herds of elephants carrying packages of data on their backs.

Why don't you stop pushing the audiophile biased stuff and look up and learn the true facts. If you are going to design a USB hub or even copying the circuit for the EVB-USB2412 you could at least measure and produce evidence (or just to help through the design cycle). There is nothing hard to measure, the digital data, look for noise before and after, what else.

Stop fooling yourself over a basic digital transport system, that's all it is, these are basic USB hubs that's all, nothing special and USB data is digital as is a lot of data these days, not rocket science.

There is nothing special about this, why don,t you try a basic USB hub you'll get the same benefits.

 

I'm not saying that there is anything special about these USB hub implementations except some attention to the power supply & that should give you some clue as to what is being addressed - it's giving more energy to the herd of elephants carrying the packets of data.

 

I won't waste my time with your rehashed arguments unless you can give a possible way to measure the energy of a herd of elephants?

[alubis]

I'm not saying that there is anything special about these USB hub implementations except some attention to the power supply & that should give you some clue as to what is being addressed - it's giving more energy to the herd of elephants carrying the packets of data.

 

I won't waste my time with your rehashed arguments unless you can give a possible way to measure the energy of a herd of elephants?

Hifi News did measurements when reviewing the Melco and the Aurender units and showed improvements on the a weighted s/n ratio and jitter on the dacs attached to these units. Maybe that's a good start for measurement wise.

 

Sent from my LG-D802 using Computer Audiophile mobile app

[marce]

I'm not saying that there is anything special about these USB hub implementations except some attention to the power supply & that should give you some clue as to what is being addressed - it's giving more energy to the herd of elephants carrying the packets of data.

 

I won't waste my time with your rehashed arguments unless you can give a possible way to measure the energy of a herd of elephants?

 

My main concern is lack of isolation for any noise, no layout that I have seen takes noise coupling into account, so even though adding a decent 5V is to be lauded, the HF noise from a PC will still couple down the USB cable and across the USB hub layout, mainly by capacitive coupling. You need a defined moat crossed preferably by a pi filter consisting of caps and a FB or inductor for power, the USB lines can use a device similar to this...

http://www.coilcraft.com/pdfs/0603usb.pdf

 

As to elephants, male African are the best as they can carry larger packets of data.. As to the energy level of a herd of elephants, easy bomb calorimeter, they produce plenty of burnable matter... job done, extrapolate the total energy from the results....

[marce]

Hifi News did measurements when reviewing the Melco and the Aurender units and showed improvements on the a weighted s/n ratio and jitter on the dacs attached to these units. Maybe that's a good start for measurement wise.

 

Sent from my LG-D802 using Computer Audiophile mobile app

 

Looked at the Melco unit, what worry's me is that what looks like a solid well designed bit of kit has a basic digital interface so bad that some add on USB hub can improve things!!! I will try and find the measurements... unless you have a link.

[mmerrill99]

My main concern is lack of isolation for any noise, no layout that I have seen takes noise coupling into account, so even though adding a decent 5V is to be lauded, the HF noise from a PC will still couple down the USB cable and across the USB hub layout, mainly by capacitive coupling. You need a defined moat crossed preferably by a pi filter consisting of caps and a FB or inductor for power, the USB lines can use a device similar to this...

http://www.coilcraft.com/pdfs/0603usb.pdf

Ah right, you are discussing noise issues on digital data transmission & not whether the data arrives intact or not - good!!

 

Yes CM noise is an issue in USB transmission & few, if any USB audio devices address this. Agreed that most USB hubs don't directly address this (one device that I know of has CM chokes in it's output lines) but they may indirectly be addressing this CM noise & other issues from affecting the USB input of the audio device.

 

What are the other possible issues? Well USB is a differential signal which means that the accuracy of the balance between the two signal lines, D+ & D-, is paramount in achieving effective noise cancellation. Differential lines operate on the principle that equal & opposite signals travel down both lines & they are tightly timed to each other. In this way the advantages of differential noise suppression can be realised. This often isn't fully appreciated & some people think that differential line will solve all sorts of noise & speed issues. This is true only if an accurate balance between the signal lines is maintained.

 

So do these USB hub devices offer a better balanced differential USB signal on their outputs?

 

Yes, according to John Westlake's eye diagram measurements of without/with Regen

The Analogue scope measurements of the USB direct and ReGen USB revealed the truly "horrid" nature of the USB traffic from a PC with heavy "CPU Process" jitter modulation - and I've been trying to think how to graphically capture it so I can post it here on PFM.

 

So I dug up a Digital scope - rearranged the lab to make space for it... I think its the first time I've really used it - I hate them, but it proved useful to capture the data.

 

 

Above is a colour graded eye pattern of the Direct PC USB connection to an XMOS based DAC (streaming 1KHz, 0dB FS) High speed USB.

 

Note the multitude of lines, but more importantly that the background is not black (Black means no data points fell in this area) - the background its dark blue because during the acquisition low frequency "Runt" waveforms where sampled in this area - these "Runt"waveforms occurred as the PC / operating system processed other applications / Operating system house keeping tasks etc. On the Analogue scope it was a horrific mess...

 

 

Now

with the ReGen USB Data, notice not only the much cleaner waveform but far more importantly that there is very little "Runt" data

- the background is Black. The USB Hub IC in the Regen has for the most part cleanly repackaged the data.

 

The colour grade data sample hit size is the same for both plots (20K Hits on the Red).

 

Those plots clearly show that the Regen gets its primary job done (reducing USB jitter which should lead to reduced PHY noise). What is more John basicly validated Regen's concept by saying:

 

Yes, I strongly believe that the USB Packet jitter cause "second order" effects in the MDAC (PSU, Ground plane and RF modulation).

 

I realise that the MDAC's USB device (the TAS1020B) not only decodes the USB, but its also the house keeping processor on the MDAC mainboard - so its directly connected to the ESS DAC (via the ESS's I2C MCU configuration port) allowing multiple RF coupling paths between the external USB Host device (PC / Computer) and the ESS DAC.

[The Computer Audiophile]

I like discussions of this stuff, but keep it civil folks.

[juanitox]

I am very impressed with the sound! There is more focus and a deeper soundstage than before. Also a lower noise floor. I was using the Uptone Audio Regen and two Audioquest Jitterbugs before I got the Revive, and the Revive is much better using the same linear power supply! Highly recommended.

 

what is impressive is a first post like this one from a fresh member,for a new product and nobody seems to notice it ?

it is summertimes times too much relaxing

[audioarcher]

what is impressive is a first post like this one from a fresh member,for a new product and nobody seems to notice it ?

it is summertimes times too much relaxing

 

Oh yeah. How could you forget to haze the new guy?

 

Anyway, I plan on doing some more in depth comparisons between the Regen and Revive when I get some time. Also plan to use them in combination to see if there is a benefit. Already using the Jitterbugs passively and that seemed to be a good thing.

[markwb]

Tried the Revive for a bit and my Mcintosh and Brooklyn had a hard time seeing it. When it did work, like the others, I couldn't hear any audio improvement. To recap, I've now tried...

 

Revive

BMC Dac1

Regan

 

PS Audio now has one that I could see using in my business for certain clients/situations as it runs over ethernet up to 300'. I'll test it. LANRover USB Transporter | PS Audio

[YashN]

The USB data stream that goes to the DAC its digital data in packets so it is read or it isn't read and USB interfaces are pretty solid so the data is going to get through so account for the difference you percieve....

 

That's an overly simplified and even erroneous view of how async USB audio in audiophile system works...

 

I suggest you take some time and read everything that John Swenson has written about the subject here and also in his interview over at Audiostream.

 

You're not getting it right at all. It isn't about getting the data through or not.