Uptone Audio Regen - Clock Mod

[HenSch]

Dear USB Regenerators,

 

I've decided to raise up this new thread, so that we can share our experiences and hints around modding the clock of the Uptone Audio Regen without having to find it all over the original Regen thread.

 

I'll start with the original postings to bring all already published information here.

 

All the best, Henning

[HenSch]

This is where it started:

 

I've recently upgraded the clock of my Regen Amber:

 

[ATTACH=CONFIG]19781[/ATTACH]

 

[ATTACH=CONFIG]19782[/ATTACH]

 

The clock I've chosen is a NewClassD Neutron Star Reference Clock with 24.000 MHz. The clock features an own separate low-noise power supply and galvanic insulation towards the Regen. For further Information check out here: www.newclassd.com

 

The careful disassembly of Regen's clock was a quite easy job to do.

 

The clock upgrade resulted in a further, significant increase of SQ. Definitely greater than I've expected when I decided to take this experiment. Subjectively said it is about doubling the positive impact Regen Amber brought to my system!

 

There is again an instantly noticable portion of increased air, room information, realism and emotion in the overall sound. Quite unbelievable and breathtaking. Sending a chill down my spine during listening to already well-known tracks.

 

So I would just like to encourage the diyers around here to take this step. It's more than worthy the efford and extra costs and it literally takes the Regen into extremes.

 

All the best, Henning

[HenSch]

John Swenson's comment and thoughts about it:

 

Something very strange happened, I actually have a few minutes free so I can talk about this.

 

First off on REGEN clock jitter in general. The whole purpose of the REGEN is to improve the signal integrity so the USB PHY in the DAC generates less noise. Jitter is a PART of the signal integrity, but as far as I know not a very large part. Meaning going into ultra low jitter territory should not make much of a difference. I have designed a few USB PHYs and none of those would have much of any noise difference when the incoming jitter goes from really good to really really good. But that doesn't mean all PHYs behave the same way.

 

Note that the clock in the REGEN is not the same as the clock in the DAC that feeds the DAC chip(s). THAT clock is very important. The REGEN clock is not even the clock that is in charge of the timing of the I2S signals to the DAC chip, that is part of the DAC again. It is not even in charge of the USB processing in the DAC's USB receiver, that is controlled by the clock connected the USB chip in the DAC. About the only thing it can possibly affect is the PG noise from the PHY.

 

The Neutron Star looks like a well implemented external clock but I have not seen a phase noise plot for it so it is hard to tell how good it really is. If anyone has actually seen a phase noise plot I would like to see it.

 

The connection of the Neutron Star to the REGEN shown earlier in this thread shows an unterminated connection. The coax is just connected across the original clock pads. This is not necessarily the best way to connect a clock. The BEST way is to have a termination resistor at the destination side that matches the impedance of the cable, which I presume is 50 ohms. But in order for that to work the output impedance of the clock also needs to be 50 ohm. I did not see anything in the documentation which specifies the output impedance. There is an output transformer but no information on its characteristics or the circuit driving it. So given the unterminated connection and non-specified output impedance, there are likely to be reflections at the connection to the board. Given the fairly short length of the cable they may not have any impact on the hub chip, but who knows, I certainly have not done any analysis on the SI sensitivity of the hub chip clock input.

 

All my previous experimentation with DAC clocks has shown that the external clock REALLY has to be much better than the on board one it is replacing to make any significant difference, the connection from board to board almost always adds enough signal degradation to partially counteract the "goodness" of the external clock.

 

Because of all of the above I was surprised by the amount of improvement heard with the Neutron Star. I would have assumed some small improvement, but not doubling the improvement of the REGEN. The only thing I can think of is that if this was a system that was already highly optimized, so the SI was already very good, the SI improvement of the off the shelf REGEN would not be all that large, so maybe in that case lower jitter may have larger percentage of the total improvement.

 

I want to emphasize that I am NOT recommending that everybody go out and spend $600 upgrading the clock. There is not nearly enough information to know how effective this is going to be on most systems. If you REALLY want to spend the money trying this you are of course free to do so, (it does void the warrantee), but be prepared that it may not double the improvement in YOUR system.

 

John S.

[HenSch]

A few fellows have already PM'ed me about some further instructions for performing the clock mod.

 

So here we go:

 

The 5V pad on the Neutron Star Reference Clock must not be soldered, the standard configuration of the NeutronStar is 3,3V and this fits with the USB Hub Chip on the Regen which is a SMSC USB2412, datasheet is available online.

 

I've started the disassembly of Regen's original clock with a small file, carefully filing away a good amount of the solder at the four pads of the clock. Then I put a pliers between the two long sides of the clock and disssembled the top cover of the clock. Behind the top cover there is some plastic-like material, which can also be taken away with a pliers quite easily. Only after taking away most parts of the clock this way I would use a soldering iron, if necessary at all. I could go fully without desoldering. Desoldering of such a device without the mechanical work is a quite risky, because you would need to heat all four pads at the same time. This big heat would risk some damage on the PCB.

 

The coax cable that came with the NeutronStar can be run through the LED hole in the small faceplate on the Regen. Unfortunately that means that the beautiful Amber LED has to go as well. This can also be done with a pliers easily. Just grab this little thing, pull and turn it a bit simultanously.

 

The face plate is a bit edgy, so I recommend putting a small bit of heat shrink tube at the place where the cable goes through the faceplate. Please put this tube on the cable before soldering the cable end on the PCB. To have some strain refief, I've applied a bit of a bigger heat shrink tube over the smaller one.

 

Soldering the cable end on the PCB is very easy, because the solder pads of the original clock have a decent size. Just don't forget to tin the cable ends before the soldering. As you can see on the foto, the two pads closest to the USB Hub chip in the middle of the Regen are the ones to go. Solder the ground line (the outer shielding of the coax cable) to the pad facing the "REG5" and the inner part of the coax cable to the pad next to the USB input of the Regen.

 

Sonically the NeutronStar needs about a week to fully run in. At the beginning you might notice a little bit of hardness. This went away after run-in and now everything sings just beautifully.

 

After(!) the run-in you can fine-tune the sound by carefully adjusting the trimmer that sits on the NeutronStar next to the oszillator. Don't move it much, though. I turned it by about 5 degrees which gave me a significant increase in the overall musical flow.

[HenSch]

Please be aware:

 

About a week ago I found out, that the NeutronStar Clock (and probably any other external clock) MUST NOT be active while the Regen itself is powered down.

 

This happenend to me during some A-to-B comparison between the modded and the original Regen. After some time the DAC was suddenly not reachable anymore through the modded Regen. After connecting it to a PC, Windows still recognized an attached USB device, but could not identify the Regen.

 

Lars Clausen from NewClassD was a great help during the troubleshooting, his customer support is really great. But nothing helped, I assume that the clock input buffer of the USB Hub Chip on the Regen has become faulty.

 

Luckily I had a spare Regen Amber and after soldering the NeutronStar to this one, everything works flawlessly again.

 

So again, please take care and do not power up the NeutronStar Clock when the Regen is without power.

 

Always power the Regen first and then the NeutronStar!

[audio.bill]

Most users would normally keep their Regen powered up, but what would happen with the external clock setup after a loss of power when the power is then restored? Would this situation also cause the Regen to be damaged?

[HenSch]

Most users would normally keep their Regen powered up, but what would happen with the external clock setup after a loss of power when the power is then restored? Would this situation also cause the Regen to be damaged?

 

I don't think so.

 

After a power loss the Regen and the NeutronStar Clock will keep running only a few seconds, until the capacitors of their individual power supplies are discharged below a certain voltage. You are right that during this phase the Regen could lose its power a bit quicker than the external clock. But this short time should not be harmful to the USB chip on the Regen.

[_JL_]

Hi Henning,

 

Thanks for the information on the mod.

 

I just did the mod today and your caution above came just in time.

 

I did unplug the power to the regen while the Neutron Star clock is powered on a couple times as the PC appears to not recognize the Regen with the clock not running. Luckily my Regen still works (fingers crossed).

 

I am quite surprised that the regen's hub chip could be damaged by clock signals? That seems very improbable to me as the signal should be quite low in level. Could it be due to some other reasons, e.g., static discharge?

 

Removing the original clock chip from the regen PCB is quite a challenge to me. I couldn't open the cover of the chip so eventually have to heat the chip (using two soldering irons, left and right) to remove it. Fortunately nothing is damaged.

 

I did found some special tools available for removing smd chips called "Chip Quik". I didn't try it myself but it seems quite easy with that.

 

Btw, you mentioned the trimmer do you know what it does? Does it vary the osc freq or what? I sent an email to newclassd asking this but received no reply.

 

Finally, the sound - well too early to say anything obviously as I just did it today. First impression is that it seems to improve resolution and ambiance retrieval as you mentioned. The sound is a bit rough now so I will reserve judgement until it has some more time on it.

[HenSch]

Great to hear that your mod went sucessfully!

 

You are right, the Computer does not recognize the Regen without the clock running. So when connecting the modded Regen it is safe to proceed like this:

1. power Regen

2. power NeutronStar

3. connect Regen to Computer / streamer

 

With the trimmer you can vary the frequency of the clock, indeed.

 

My first impression during the first week with the NeutronStar was a bit of hardness as well. So don't worry, that will go away after the break-in. But still after the break-in I found the modded Regen sounding a bit too analytical for my ears. You will be surprised what happens to the sound when carefully tuning the trimmer. Especially voices gain an outstanding realism and smoothness when tuned right. Doing too much on the trimmer will turn voices sounding artificial and congested though.

 

So have great fun with the modded Regen and keep us updated.

 

Henning

[cmarin]

Henning,

 

Thank you for starting this thread. It's been very helpful.

 

Can you provide a picture of the final installation in your system? I'm curious whether the external clock and power supply have outer cases.

 

Best regards,

[Booster MPS]

This is where it started:

 

I've recently upgraded the clock of my Regen Amber:

 

[ATTACH=CONFIG]19781[/ATTACH]

 

[ATTACH=CONFIG]19782[/ATTACH]

 

 

From second post in this thread

[_JL_]

Henning,

 

Thank you for starting this thread. It's been very helpful.

 

Can you provide a picture of the final installation in your system? I'm curious whether the external clock and power supply have outer cases.

 

Best regards,

 

I put it together into a small box. As the power supply is mains-powered it is unsafe to use it exposed.

 

I grounded the alum box, added a fuse, and a snubber at the PSU board's input to suppress the power on/off noise.

[HenSch]

Henning,

 

Thank you for starting this thread. It's been very helpful.

 

Can you provide a picture of the final installation in your system? I'm curious whether the external clock and power supply have outer cases.

 

Best regards,

 

Up to now I haven't put the NeutronStar into a case, but that is on my to-do-list.

 

Right now I'm powering the NeutronStar with a Lithium-Polymer battery (3s LiPo, 2.600 mAh), which gave me a further slight improvement in SQ over any LPSU I have tried. Quite tiny difference, but once you have tasted even sweeter fruits in audio it is impossible to do without, is it?

 

Managing the battery charging is a bit annoying, though. On top of that a LiPo battery can be dangerous when treated wrongly, especially deep discharge.

[HenSch]

Hi _JL_,

 

very clean installation you have done, nice!

 

Please let me share one thought that came up in my mind. I might be a bit of a hypochondriac regarding EMC/EMI type of things, but the proximity of the mains transformer and the coupling transformer of the clock strikes me. I would feel better with two separate housings for the PSU and the Clock in order to prevent any interference between the two.

 

For doing this you would have to modify the power connection between PSU and the clock. It is good that the PSU has a separate screw terminal. Due to the special power connector on the NeutronStar however, you would have to cut the original cable. In this case the blue cable and the one next to it are ground. The other two of the four are plus.

 

Another option would be putting a metal plate (f.e. copper) between the PSU and Clock inside of the case.

[cmarin]

Henning and JL,

 

Congrats on the installations and thoughtful configurations. I'm afraid I'm at the the opposite extreme of a DIYer. Clueless is more like it.

[_JL_]

Hi _JL_,

 

very clean installation you have done, nice!

 

Please let me share one thought that came up in my mind. I might be a bit of a hypochondriac regarding EMC/EMI type of things, but the proximity of the mains transformer and the coupling transformer of the clock strikes me. I would feel better with two separate housings for the PSU and the Clock in order to prevent any interference between the two.

 

 

Thanks for the suggestion. That makes the two of us. In fact I originally bought another much bigger chassis so as to provide more physical separation between the PSU and the clock module. Turns out the chassis is way too big to fit in my rack so I gave up and bought the present one.

 

Next thing on my list is to try another LPSU. Do you know the type of the power connector linking the two modules? If I can buy another one then I don't have to cut the present one.

[Blizzard]

Hi _JL_,

 

very clean installation you have done, nice!

 

Please let me share one thought that came up in my mind. I might be a bit of a hypochondriac regarding EMC/EMI type of things, but the proximity of the mains transformer and the coupling transformer of the clock strikes me. I would feel better with two separate housings for the PSU and the Clock in order to prevent any interference between the two.

 

For doing this you would have to modify the power connection between PSU and the clock. It is good that the PSU has a separate screw terminal. Due to the special power connector on the NeutronStar however, you would have to cut the original cable. In this case the blue cable and the one next to it are ground. The other two of the four are plus.

 

Another option would be putting a metal plate (f.e. copper) between the PSU and Clock inside of the case.

 

Which DAC are you using in combination with this modded REGEN?

 

Have you already swapped the Master clock out in it?

 

Have you tried upgrading the USB interface?

[HenSch]

 

Next thing on my list is to try another LPSU. Do you know the type of the power connector linking the two modules? If I can buy another one then I don't have to cut the present one.

 

I have no idea which type of connector that is, haven't seen such thing before. When ordering the NeutronStar I asked for a spare cable for my LPS trials and Lars Clausen was very kind to send me one extra cable without extra charge. So I suggest that you ask Lars for an extra cable, I'm sure that he will be helpful.

[HenSch]

Which DAC are you using in combination with this modded REGEN?

 

Have you already swapped the Master clock out in it?

 

Have you tried upgrading the USB interface?

 

I'm using the Auralic Vega DAC in combination with the Aries streamer, connected with a Tellurium Q Black Diamond USB cable.

 

After the Regen mod I'm deeply satisfied with the sound quality I get out of this configuration.

[Blizzard]

I'm using the Auralic Vega DAC in combination with the Aries streamer, connected with a Tellurium Q Black Diamond USB cable.

 

After the Regen mod I'm deeply satisfied with the sound quality I get out of this configuration.

 

I just can't help but think that upgrading the Vega master clock would provide far better results for much less $.

 

The Vega currently uses a Crystek 575 series clock. For $250 there's drop in replacement clocks (same form factor) out there that would drastically improve the SQ of the DAC.

 

But I suppose this can always be done in addition as well.

[HenSch]

I just can't help but think that upgrading the Vega master clock would provide far better results for much less $.

 

The Vega currently uses a Crystek 575 series clock. For $250 there's drop in replacement clocks (same form factor) out there that would drastically improve the SQ of the DAC.

 

But I suppose this can always be done in addition as well.

 

Well, modding the Vega during its warranty period is not an option for me right now.

 

Nonetheless I'm quite confident that optimising the incoming USB data stream as perfectly as possible is the first step to take to get optimum results from a USB DAC.

 

From my experience with Computer Audio, a perfekt back-end (i.e. the actual D/A-conversion) reveals a lot of the shortcomings of a suboptimal front-end (i.e. USB source and USB DAC Interface). Therefore the resulting sound is substantially more incoherent when you have a bad front-end and a good back-end than vice-versa in my opinion.

[Blizzard]

Well, modding the Vega during its warranty period is not an option for me right now.

 

Nonetheless I'm quite confident that optimising the incoming USB data stream as perfectly as possible is the first step to take to get optimum results from a USB DAC.

 

From my experience with Computer Audio, a perfekt back-end (i.e. the actual D/A-conversion) reveals a lot of the shortcomings of a suboptimal front-end (i.e. USB source and USB DAC Interface). Therefore the resulting sound is substantially more incoherent when you have a bad front-end and a good back-end than vice-versa in my opinion.

 

I understand not wanting to mod your Vega while under warranty, but in my experience of upgrading the master clock in 2 DAC's so far, there's absolutely no downside. Every area of sound is improved.

 

At the same time I do agree that USB interfaces have a lot of shortcomings. Between your Aries and modded REGEN you have invested a substantial amount of money getting the digital signal from the source material to the USB input on the Vega.

 

It's too bad Auralic doesn't just have I2S over LVDS outputs on the Aries and Inputs on the Vega. That would be the best way possible to handle this duty.

 

Next to building the renderer into the DAC and sharing the same master clock of course.

[HenSch]

I understand not wanting to mod your Vega while under warranty, but in my experience of upgrading the master clock in 2 DAC's so far, there's absolutely no downside. Every area of sound is improved.

 

At the same time I do agree that USB interfaces have a lot of shortcomings. Between your Aries and modded REGEN you have invested a substantial amount of money getting the digital signal from the source material to the USB input on the Vega.

 

It's too bad Auralic doesn't just have I2S over LVDS outputs on the Aries and Inputs on the Vega. That would be the best way possible to handle this duty.

 

Next to building the renderer into the DAC and sharing the same master clock of course.

 

I totally agree with you.

 

I2S, directly generated out of the main CPU, would be the perfekt interconnect between streamer and DAC. This connection however has to be as short as possible, because the signals are also very touchy. Building everything into one case is surely the best way to go then. The downside of this approach is a higher complexity to provide every device with its own, indedendent high-quality power supply. Everthing has definitely its pros and cons.

 

The whole digital chain in my configuration is as follows:

 

Samsung SSD, powered by Sjöström Super Regulator -> USB / SATA converter, powered by Sjöström Super Regulator -> TQ Black Diamond USB cable -> USB Regen, powered by Sjöström Super Regulator -> Auralic Aries, powered by Sjöström Super Regulator -> TQ Black Diamond USB cable -> USB Regen with clock mod, powered by Sjöström Super Regulator and clock powered by battery -> Auralic Vega DAC

 

As you see I have a separate cabinet stuffed with power supplies. Some power supplies are filtered with mains filter and some with additional insulating mains transformer. Having independent devices in the digital chain gave me a lot of freedom to fine-tune everything to my personal favour.

 

Here is a foto of the overall ensemble:

[Blizzard]

I totally agree with you.

 

I2S, directly generated out of the main CPU, would be the perfekt interconnect between streamer and DAC. This connection however has to be as short as possible, because the signals are also very touchy. Building everything into one case is surely the best way to go then. The downside of this approach is a higher complexity to provide every device with its own, indedendent high-quality power supply. Everthing has definitely its pros and cons.

 

The whole digital chain in my configuration is as follows:

 

Samsung SSD, powered by Sjöström Super Regulator -> USB / SATA converter, powered by Sjöström Super Regulator -> TQ Black Diamond USB cable -> USB Regen, powered by Sjöström Super Regulator -> Auralic Aries, powered by Sjöström Super Regulator -> TQ Black Diamond USB cable -> USB Regen with clock mod, powered by Sjöström Super Regulator and clock powered by battery -> Auralic Vega DAC

 

As you see I have a separate cabinet stuffed with power supplies. Some power supplies are filtered with mains filter and some with additional insulating mains transformer. Having independent devices in the digital chain gave me a lot of freedom to fine-tune everything to my personal favour.

 

With I2S, converting the CMOS I2S to LVDS on the sending end, and decoding back to CMOS on the receiving end is the way to do it to allow long runs with no loss. This is what PS Audio, Sonore, Wyred for 4 sound, MSB tech and quite a few others do.

 

Wow sounds like quite a setup you have going!

 

I wonder how your whole setup would compare with a DAC with built in renderer costing the same as your total investment (minus time)?

 

I suppose there's not too many out there yet besides the PS audio direct stream with bridge, and MSB tech analog DAC with renderer. But give it a year or so and there will be many more.

[4est]

Oh, there is some loss, or jitter or what have you in the double conversion. There always is at these frequencies. I do agree that switching the master clock on the DAC would yield more for the investment, but it is not universally better. Much depends upon what phase noise is present, not just how much.

With I2S, converting the CMOS I2S to LVDS on the sending end, and decoding back to CMOS on the receiving end is the way to do it to allow long runs with no loss. This is what PS Audio, Sonore, Wyred for 4 sound, MSB tech and quite a few others do.