AC Filtering, Grounding Boxes, Linear PSU and Balanced Power.

[YashN]

Yes you can simulate leakage currents if you know what is happening, the problem is that most of the time we don't really know what is happening.

 

My explorations into leakage current wave forms show that they are radically different from PS to PS. That seems to point to you cannot simulate it with just a simple capacitor, there is way more involved than that. Because the leakage loop is a loop through at least two power supplies the important thing is how those two different non-simple models interact with each other.

 

So while it is theoretically possible to do, in practice we have no idea what model use for a given power supply.

 

On top of that we don't know exactly how the specifc leakage current waveform interacts with the other parts of the audio system to change the SQ. For example I have a suspicion that leakage current through a DAC changes SQ in a different way than leakage current through a power amp.

 

There are a lot of unknowns in this right now.

 

Thanks a lot for this, wasn't ignoring your reply, but it did send me on a path to try and understand it all. So here is a simplified way I view it in my mind, a mental map that can help me visualise and understand. If any of that is incorrect, then let me know:

 

Suppose we have 2 power supplies, A and B, each with two modes of operation DC side, Mode A1 and Mode A2, Mode B1 and Mode B2.

 

The actual Leakage current is a function of the the two PSes in their Modes at any time.

 

PS A's contribution to parasitic elements depends on its own internal AC configuration, and its own DC configuration in each mode.

 

Similarly, PS B's parasitic elements is derived internally for each mode.

 

It is the whole connection of PS A to load and PS B to the loads, and each of those PSes to the power lines that allow the Leakage currents to flow.

 

There is, of course no reason at all that PS A's Mode 1 is synchronised to PS B's Mode 1, so we also can have varying Leakage Current over time because of the 4 combinations of the Modes for these two PSUs.

 

Furthermore, the Leakage Currents thus generated because on one device's operation also interact and cause resonances in the other PS's components.

 

This explains the complex shapes of such Leakage Currents.

 

Secondly, we can also see that the Leakage Currents thus produced cannot be characterised for a single Power Supply, but can only be done for at least 2 of them.

[YashN]

I think iDefender would not help me in my case if it does not do any active filtering on ground wire. No evidence exists that $45 iDefender would do such a thing. It seems it is able to detect, if DAC uses power from USB and if not (not my case), it is able to disconnect ground and connect it again if it detects handshake attempt. If yes (my case), it let's ground connected through and allows injection of clean power like my split cable does. So I mean iDefender could not help me, if it works as I described.

There's a fair chance you're presuming too much: that things won't work if connected in a certain way and additionally, that the iDefender won't help, and that the iDefender is internally constructed a certain way or should absolutely do it a certain way for you to get results.

 

One or all of these things might be wrong.

 

Another thing where you could be wrong is how handshake occurs. What you're concerned about after handshake is actually USB signalling. This happened to me during one of my tests which I since resolved.

 

I thought I wouldn't be able to disconnect the VBus from the computer on my DAC. I now have it implemented.

 

For the iDefender, I would ask those question to iFi in their vendor sub-forum here. I doubt it works how you think it does.

 

Even if they tell you the iDefender doesn't work like that, you may still be presuming too much about it not helping though.

 

You may not get true galvanic isolation with your DAC, but if you implement it properly, you could still get vastly improved results - actually, it all depends how much the Gustard is built with regards to treating incoming to noise.

 

To what extend your Gustard is built to reduce the effects of noisy power, I don't know, perhaps Quadman or Ric Shultz might say.

[YashN]

After the initial Wow, I have been trying to re-capture some of the missing high-range content and resolution.

 

Tested smaller caps, and while they do bring in more content in these ranges, there's a hardness to it, and somehow I lose the presence and the fullness from the mid-range to the bass.

 

We had some friends over for brunch a couple of days ago, and my friend's opinion was much the same as mine concerning the overall fullness and presence and some lack in the upper ranges, so I knew where to focus on. It was interesting because I made him test all three configs: default USB cable (came with the DAC), my USB Connector + iPhone Charger, my USB Connector + Low-Noise Linear Reg PSU. Needless to say: he really liked the sound initially, but the last one was much, much better.

 

More cap tests tonight, with Vishay foil caps for smaller capacities, together with the bigger Elna -> presence is still there, and high-frequency content as well, and at last, we also get some detail and resolution in the highs.

 

Testing a Rubycon Cap, the rapidity of transients is rather astounding, something the Elna + Vishay appears to lack a little, but we lose the presence and roundness factor (probably also because the capacitance is smaller here).

 

Also tested a Solid Polymer of around 523uF, sounded detailed, but lacked the presence and roundness, overall quite clean.

 

For now the Elna + Vishay stay in, but I am looking to resolve that last part of the equation to give it the overall speed it needs.

[YashN]

It was a long time since I last saw an interesting USB cable, but this LH Lightspeed 20G cable have definately caught my attension!

 

I saw it as well and it lost my attention quite fast: long stretch of USB cables on both sides, doesn't make much sense to me unless I'm missing something.

 

I would vastly prefer the Regen over this, placed near the DAC.

Otherwise, battery is good, the concept of regen near the DAC needs no proof anymore, physical separation of the wires is good too.

[YashN]

I will not change my battery powered Regen and modded Elijah Audio cables for this either, but finally a company that understands to put this into a single unit. Soldered connections must be a good thing. Just missing a couple of things like GND lift (even if this will be possible with the coming Sbooster Vbus3), separate GND wire, loose fit silk/cotton sleevings etc. Interesting in any case!

 

They don't mention any GND Lift but that doesn't mean they didn't include it.

 

Not regenerating near the DAC still doesn't make sense. Additionally, I doubt it has the optimised noise profile of the PHY in the Regen.

[YashN]

I agree that a direct connection to the DAC is prefered...but IMHO only with a unshielded connection and with GND lift switch.

 

The shielding and GND lift switch is a side consideration to the Regeneration, which should happen ideally the nearest possible to the DAC, which the LH cable + battery doesn't do.

[YashN]

For today, I had left the combination of the Rubycon, the Elna and the Vishay to test. Had to rewire it twice on the little breadboard I hooked to the regulator board terminals.

 

Sat down and listened. The transient rapidity was indeed back, as were the highs, but it looked like I had lost the presence and fullness again. I listened quite a lot, wondering why this wasn't working, and thinking of next steps, like perhaps changing the order of the caps, but this was a bit disconcerting.

 

Finally stood up to the breadboard to rewire things and noticed that the Elna was leaning out of the breadboard because I had mounted it on a small piece of proto-board, longer on one side, so put it back in, ensured it was well connected to the rails.

 

And "Wow" is here again, big time. Presence, detail and power in the bass-to-mid regions, rapidity of the attack transients, the high-frequency content is there, but not hard, nor harsh, delicate.

 

It's all very balanced now. Took some time to get there, but so worth it. Can I find fault in it? Not sure yet, perhaps a little bit of distortion on charged passages with the Kick drum on Michael Jackson's "You Rock My World" playing as I'm writing this. Potential further tweaks necessary in case the listening sessions confirm this.

 

Tonight, a couple of friends are dropping by, so they'll be listening to the three steps again, and the last one with the special USB connection and the tweaked Low-Noise LPS should be the best they heard in my system yet. It's fun because they've been hearing my enhancements every time they visit and I think they were wondering around three levels back how I could possibly get better sound that they had already heard here.

[YashN]

Although I fully enjoy your experiments I do not understand why you would want to add capasitors or resistors into a cable design? AFAIK you would want USB to be as responsive and fast as possible. Do not care about impedance match. It does'nt matter for short lenghts. Just care about signal integrity. Reduce capasitive coupling as much as possible.

 

You're not reading properly.

 

I have made major improvements to my Low-Noise Linear Regulated Power Supply.

[YashN]

Happy 2017.

 

Last year ended with our friends dropping by for a listen and dinner and then we went out.

 

They were flabbergasted at test 3, my custom USB connector with the Low-Noise LRP compared to first, the default USB cable, then second, my DIY USB connector with the LRP.

 

Then yesterday was an opportunity of commissioning back the AC Filter box into play, the reasoning being that if the USB connector already works to remove the noise at this link, then what remains is probably the AC noise + leakage noises interacting between supplies and devices in the chain somehow.

 

Since the USB Connector already did a big change and the LRP is a two-prong floating design, I didn't expect the AC Filter to make as much of a change as my first test a while back.

 

But first, instead of re-testing my own filter lines configuration which would have been the iMac on a filter and the LRP on another filter line, I wanted to test John's recommendation of removing the filters as plugging the devices into a bare power strip, thus reducing part of the Leakage current he mentions and which is not the same thing as the usual Leakage current catered for in Medical devices, and this, in the case that you don't have any isolation transformer (I currently don't).

 

It so happens my AC Filter is indeed built upon a power strip as main element, and prior to that, I use an IEC plug with two small blue caps (which is part of the whole filter circuit). As John mentioned, if there's any filtering allowed here, then it should be before the distribution.

 

So, in the following post I will show the different permutations we tried and listened to and our impressions and results.

[YashN]

Here are the results of the listening impressions in various configurations:

1. iMac + LRP on strip directly

 

Sounds good, it did seem to lack the 'presence' I had acquired in previous configurations though. Caveat: in our config, we have a iMac ->HDMI Connection to the TV(potential of loop and noise), 3 external USB HDDs each powered by its own SMPS unit (noisy!), so you cannot take this listening impression as invalidating that recommended setup in any way.

 

2. Changed LRP plug (2-prong) orientation

 

Since one type of Leakage current can actually be reduced by changing the orientation of a 2-prong plug and it was easy to try it, I did just that. Wow, I hadn't expected that big of a change. Big bass expansion - not extension as in the bass extends further down, but bass expansion in the sense that the perceived region is wider and more defined both sides. That was very good, but we still felt a lack of that interesting 'Presence', which we detect rather easily with closed-miked minimalist tracks like Hans Theesink's Mississipi. I don't usually like Blues, but Theesink and this track are awesome.

So, it was time to put back the filter lines in the box and compare and try to see if I could find that very enthralling 'Presence' again.

3. iMac on Filter, LRP direct to strip, physically after the iMac filter if you start viewing from the AC box mains

 

Wow, big increase in perceived Power, and not only that, but 'Presence' seems to be back, the bass expansion is still here, and the rapidity of transients appear OK, but on listening again this morning, it seems there is a little lack of it. This is very good and is reminiscent of the power increase when I finished isolation the USB connection, except the increase here is much, much larger, it feels like a whole new set of gear again.

 

So, one way you can detect noise on listening, is that the noisy devices, if not filtered will rob your gear of Power to a great extent.

4. iMac on Filter line, LRP on Filter

 

Big power remained, we had an OK level of 'Presence', but also lost some transient rapidity. This is not too good for me: you lose a lot of the information about rhythm, the soundstage and the desire to move.

 

5. iMac on strip, LRP on Filter

 

Big power was still there, we had an intermediate level of 'Presence', but the transient rapidity loss is also apparent in this configuration.

 

So, today I wanted to try a few more tests to see if I could obtain all the benefits and none of the issues like losing 'Presence', Big Power and transient rapidity, which is the subject of the next post.

[YashN]

Tests done today with the AC Filter lines and overall system view:

6. iMac on Filter, LRP on separate, dedicated outlet (this puts it on the same outlet as the SET Tube amp, and not on the strip)

 

Presence was OK, highs were good too, we got the transient rapidity back (good!). However, it looked to me that we had lost some of the fullness of the bass, bass slam and ambiance, although it could sound powerful. At this listening test, my girlfriend didn't notice the lack of it. I said that the night before, in one configuration when the bass came big, it wowed me, but this sounded OK but lacked the 'wow' factor.

 

Now, I had written on paper that step 7 would be to put an HDD on a filter line. However, seeing that the USB connector already deals with the interference there, I had the idea or actually testing the TV on a filter line because A/V gear can be incredibly noisy as well and remember, the iMac mirrors its screen onto the TV often when I am listening to Audio.

 

7. iMac + TV on Filter lines, LRP on separate, dedicated outlet

Wow! Bass, slam, ambiance back. Now my girlfriend noticed what was missing in the last configuration. So this particular configuration for us currently gives us the bass expansion, the big power, the highs and the rapidity of transients and the feeling of 'Presence' as well.

 

The TV and the iMac is a wicked combination, robbing us of a lot of SQ! The initial test with the iMac and the LRP on the power strip (without filters) could have given us a much different outcome if the TV hadn't been linked to the iMac.

 

Overall, one of the biggest effects you can hear with a noisy system is that of much decreased Power. We can hear this, even with series Filters which themselves, by virtue of topology, perform a measure of insertion loss!

 

If you haven't checked with a Multi-Meter the presence and quantity of Leakage current in your gear (there's a method to it, and you have to be careful), I strongly suggest you try changing the orientation of any 2-pronged device and listen for any changes.

 

Really happy so far with the new AC Filter tests I performed and the outcome today.

[YashN]

If you haven't checked with a Multi-Meter the presence and quantity of Leakage current in your gear (there's a method to it, and you have to be careful), I strongly suggest you try changing the orientation of any 2-pronged device and listen for any changes.

 

It's worth mentioning here that once you find the proper orientation of the plug, you should mark the end of the plug and depending on how your socket in the wall or elsewhere is made, mark one end of it as well.

 

In Canada, we have one longer slit for Neutral and a shorter one for Live, so I only needed to mark the prong which corresponds to the Large one for instance.

 

For devices which have a reversible orientation at the chassis connection, it's better to mark it there as well.

[YashN]

Turns out I have been improving our video setup as well, so during these holidays, since I had re-commissioned the AC Filter box, I had a few side ideas.

 

First, one was trying the DIY 2-prong power cord that I usually have installed on the SS amp but this time on our 4K UHD Blu-Ray player. This power cord is solid-core, with live and neutral double shielded and separated, twisted pair, and the shield-to-ground is only connected AC mains side (3-prong into the mains, 2-prong into the device).

 

Turns out one of the usual blue ratings screens has a more vibrant blue to it. The 20th (or is it 21st) Century Fox announce screen has more vibrant yellows and orange. This wasn't subtle at all, it was very apparent.

 

It looks like interference on the power line could change the colours.

 

 

We also re-tested our Blu-Ray of The Drop, with the superlative Tom Hardy, which we had watched upscaled to 4K. In 4K upscale mode, not just with that movie, I usually perceive a really, really slight colour-displacement effect on the edges of objects. This time, this is gone or reduced.

 

 

We also tested the opening credits of Life of Pi (4K UHD Blu-Ray) and found the PQ better here, clearer, with the concomitant detriment side-effect of seeing when CGI is used more clearly (!).

 

In a past post in this thread, I had already noted in passing that adding the iMac to a filter line made the fonts on the TV clearer, and this is true again this time around.

 

Yesterday, I thought of checking quality again since I also added the TV on a filter line.

 

 

We have binged on a Belgian production of an intricate and slow-grind, small village murder mystery called The Break on Netflix and here again, with the TV also now on a filter line, the small lines in the opening credits are clearer, close-ups on faces are clearer, there appear to be less artifacts as the UH Blu-Ray player upscales this HD show to 4K. Colours appeared more distinct in the same type (e.g. different shades of green), and overall the PQ appears more realistic, tested also with the opening of Life of Pi.

 

I don't see people writing a lot about this after a brief search online late last night.

 

It is an easy test to do if you already have an AC Filter or AC Conditioner box though and if you have a keen eye, with some high-resolution gear and upscaling capability. It also helps if you have already calibrated your screen and know your video gear's usual PQ abilities in regular sessions.

[YashN]

Happy 2017 YashN!

Thanks for a very interesting read!

1. All battery chargers and tablet charger are connected to this Hugo! powerstrip that I always turn OFF while listening to music.

 

2. My Pioneer U-05 DAC/HPA/PRE is my one and only AC mains connected device. It is connected to my Peaktech IT and to my ATL in-line DC blocker before the wall outlet.

Thanks, same to you for 2017.

 

I have a set of batteries I can use to test the new setup, normal 9V and potentially more interesting things to do with the LiFePo4 ones salvaged from a malfunctioning PC laptop battery.

 

I have plans to go much further than that as well but this is probably not for this forum.

 

For batteries, it is going to be interesting to compare them to the next iterations of my Low-Noise Linear Regulated Power Supply (which is gong to be even better although for now I have a hard time imagining how better SQ could sound) as batteries have their own inherent noise profile. You can minimise this by careful selection of capacitors to go with them. I believe John Swenson mentioned low-ESR capacitors but I might be mistaken, I'm writing from memory here.

[YashN]

merry new years you lovely people.

 

I got the battery power supply with the regulator. It's designed to break the 5V with an in out usb. I have just used the 5V out to supply from the battery via the regulation circuit.. So far I haven't heard much of a benefit nothing I can say above the battery bank it replaced.

 

To you as well, Middy.

 

You're powering a USB-powered DAC with it?

 

There could be little difference comparing battery to battery, it depends on the type and configuration (use of and type of capacitor).

 

When you measure the output does it give 5.0V or something else?

 

I'd say that when you're done charging with it, completely disconnect the SMPS charger from the mains as well to prevent any possibility of Leakage loops and current (I don't know how your other gear is powered or connected).

[YashN]

Turns out I have been improving our video setup as well, so during these holidays, since I had re-commissioned the AC Filter box, I had a few side ideas.

 

In a past post in this thread, I had already noted in passing that adding the iMac to a filter line made the fonts on the TV clearer, and this is true again this time around.

 

Yesterday, I thought of checking quality again since I also added the TV on a filter line.

 

Yesterday, I added a third filter line to my DIY AC Filter box - the original intention is to check whether filtering an external HDD power still does a noticeable change in SQ.

 

But, since I was disconnecting everything to do that anyway, I thought of putting the UHD Blu-Ray player with the DIY power cord on a filter line this time, so the configuration is like this: iMac on a filter line, TV on a filter line, 4K Blu-Ray Player on a filter line and with the DIY power cord.

 

Straight away, the Samsung player's default screen is clearer, more contrasted: my girlfriend notices this with the Samsung Apps icons on the right, while I notice this clearly with the lower App bar, which contains Netflix, Youtube, UFC and a couple of other things, but each square icon for these apps with their logos is within slightly larger black square, and the whole background of this screen is gray.

 

Well, we already had good colour distinction between the logos of these apps (the reds are distinctly different), but now that black is darker, there's a sense of less bleed.

 

So, we re-tested with Life of Pi and The Drop - more realistic, the feeling of seeing through a window was greater. We tested with Netflix: the opening credits of Sense 8 (crappy show but great pictures in the opening credits in 4K), and we were wowed again: it was clearly more detailed, with better dark areas and overall contrast.

 

 

I also showed her once more The Crown (4K), Episode 2 where they are doing a safari in Kenya, and for a while we were taken up by the quality of the images.

 

The whole Netflix interface shows more contrast and less bleed - these two might actually be related though, in the sense that if you resolve the 'bleed' noise, then the contrast perceived will be different, better.

 

We also did brief tests on Longmire and Bloodline, and in the latter there's a scene at the beach where two characters have a conversation, and one of them drags a Kayak onto the beach: seeing the small droplets on the Kayak, the details of the algae on the sand, as well as the darker shade of his sunglasses, together with the details of the fabric of his hat was quite amazing.

 

 

We then hopped into the Youtube app and watched a few 4K videos like the Sony demo ones on animals and underwater as well as other gorgeous landscape ones with the same observations on detail and contrast.

 

This is fantastic, and it appears that noise on the AC mains can also spoil our enjoyment on movies greatly as well. The iMac image while writing this is clearer as well, better blacks, less bleed.

 

Two things are sure: I will have to design and build a videophile AC Filter box on top of finishing my Audiophile AC Filter box, and secondly, I most probably have to go through the video calibration procedure again!

 

It felt like we had new video gear yesterday, so well worth it!

[YashN]

I returned home after my holiday so I could try it.

It doesn't work - as I expected.

It seems to me that some current has to be flowing between VBUS and ground on computer USB port, otherwise XMOS driver considers DAC to be disconnected.

I will order resistors to follow sandyks schematics http://www.computeraudiophile.com/f6-dac-digital-analog-conversion/continuing-pursuit-power-supply-improvements-and-improved-digital-analogue-converter-performance-14165/#post200854

What seems to be interesting on 2nd sandyks schema: I read also in this thread that the ground conenction has to be short, of the lowest resistance. And now sandyk recommends to add resistor. So ... lowest possible impedance for USB ground connection or not?

Yes, that's a must do in your config.

 

Lowest impedance for shunting noise, but when that low-impedance is also sending noise to where you don't want it, i.e. the DAC, then you'd rather impede that connection.

 

Not sure why the connection should be short though but in my setup, I've kept the data lines quite short, so by default the GND line is rather short too, but it does also pass through a couple of circuits as well.

 

Looking forward to your listening impressions with the Gustard.

 

I don't know if you've followed Ric Shultz and Quadman when they modified their Gustard for even better SQ, but there's an interesting thread with the info on WBF.

[YashN]

Changed the layout of my Linear Regulated PSU yesterday, allowing both a smaller current loop in the adjustment network of the LM317 as compared to the previous implementation, and the installation of the return sense line.

 

Last night's listening session was rather short as it was getting late, but we though we obtained more details in the mid-range - certainly hearing new things brought to our attention is a few songs we listened to.

 

It did look we lost some 'Presence', rapidity of attack transients and some of the bass expansion/fullness though. However, I will need to check first, whether I made any mistakes in the revised layout, and secondly, whether the caps circuit on the micro-breadboard haven't moved or disconnected in some way, which would explain some of the changes.

 

Today, I wanted to test the addition of a small cap on the output for the attack transient as recommended by the datasheet but the negative on the power output jack had disconnected, so I had to redo that. I also took the opportunity of re-testing of the output voltage and the pot which allows its setting as well as placing the caps and the cables firmly again in the micro-breadboard. I actually should fix them on a little proto-board circuit though.

 

Listening to a little playlist made by my girlfriend while she does her DIY too (jewellery for her). Sounds good so far, clean mid-range, sounds like the attack transient rapidity is back, probably that it was simply that Rubycon cap which was dislodged.

 

Will listen a bit more as is for now, until I make some new enhancements to the existing circuit or else as add-ons or compare to an even better, lower-noise regulation circuit. on the playlist, she has added:

 

- Alain Souchon & Laurent Voulzy - Derrière les mots,

- Chris Cornell - Euphoria Morning,

- Angélique Kidjo - Djin Djin,

- Katie Melua - Live, underwater,

- Santana's Greatest Hits and Natalie Cole's Greatest Hits Vol. 1

[YashN]

After some further testing and experiments with the DC blocker I have realized that even if it brings great high frequency details and bass details it will actually remove the low end bass performance...especially on its own.

Using it with the Supra F-CON the bass performance is actually enhanced...but with only the Axing inline the low end bass seems to be vanished completely. Quite annoying!

 

Hi Cornan, I see the tests are ongoing on your side as well at this start of the new year!

 

For DC blockers and mains, I really have only seen them recommended for large-rating toroidal-based transformers because the DC offset can make the core saturate and then cause mechanical noise and probable subsequent SQ effects.

 

iFi also does a small DC purifier that can clean up, as mentioned officially, after SMPS power supplies (so probably doesn't apply to your setup here), but I believe I have read people placing it at the output of a Linear PSU and reporting even better SQ this way too.

 

I know what you mean by that feeling of getting great sound and then another change in, and it then feels like a step back.

[YashN]

I have been following your experiments with great interest. Tried the other day to add my Entreq Minimus to my Blu-ray with great result. A much more vivid picture with fuller colours and a touch sharper picture. Sadly I'll need the Minimus for my router any day soon!

 

Glad you tried it on Video!

 

After some more searching I did find an old thread on AA where John Swenson, Al Sekela and others write about their experience using a choke for audio and the great results, and in the thread someone mentions in passing that he actually started with video and then wanted to try the choke on audio, so some people have been experimenting with these for a while.

 

It would be interesting to try and dissect the actual way the AC filter lines clean up the PQ: certainly has to do with Ground loops and other noises on the mains, perhaps Leakage Currents as well.

 

However I would like to know if it is indeed the reduction in bleed (like in any LCD screen) where there is a halo effect around bright objects bleeding into dark regions right at the edge, that provides the better contrast, and in turn provides greater clarity.

 

The mechanism for brighter and more realistic colours would be interesting to know as well.

 

Not having 4K UHD gear providing their utmost quality because of noisy AC mains seems like a waste to me, just as having high-res audio gear not providing their best SQ-wise.

 

Here I am writing this with the iMac screen mirrored on the 4K TV, and despite F.lux managing warmer colours because it is night-time, I can still detect how dark the blacks are in Audirvana+ playing Natalie Cole as well as a black background I set up in the main screen of LTSpice.

 

These are the kinds of enhancements that I really like: the really obviously positive ones that impress even after a few days.

 

Already decided to build another AC Filter box specifically for the video gear, can't do otherwise now.

 

Of course, we want to watch more movies and TV Shows now.

 

 

Last night we watched a 4K upscale of our normal Blu-Ray of "Tinker, Tailor, Soldier, Spy" with a plethora of great actors: Oldman, Hardy(!), Cumberbatch, Hurt, Firth, but the image quality of the movie itself was a bit disappointing - quite grainy and a lot of digital filters to give the photography an 'old seventies' look. I didn't like it too much, it was too plodding for me, probably works much better as a novel as many adaptations do.

 

We're certainly going to watch some more though, I would like to watch a good Western soon as well. Cinematography is quite great in some of them, even the older ones.

[YashN]

I figure my Blu-ray would improve with better AC cable as well, but since it is built in I have never bothered to try.

 

My DIY AC power cord sure did have a rather obvious effect on the colours and clarity on our 4K UHD Blu-Ray player, so well worth a try as well (that was even before I put all the video gear on the AC Filter box which brought even more enhancements).

 

Here is my favourite western movie. Still have'nt seen a better one!

 

 

 

We have it on Blu-Ray too! It was a contender for tonight, we ended up watching this with Mads - quite good as well although I'm not fond of too many digital filters:

 

 

It was fun to watch a Nordic Western - actually a Danish, UK and South African collaboration.

[YashN]

There are definitely some cool experiments to be done with Ethernet with regards to isolation.

 

The iFi DC purifier is interesting as well in that it is post-PSU (so usually prior to the DAC if using it there).

 

I found a little USB charger battery pack nearby so I am going to try it with the DAC as well - it will require a micro-USB to USB adapter that I will have to build and then I can do a comparative test.

 

I am also reading about the LM317's foibles and how to mitigate these. It is quite interesting for learning despite the fact I could just get a much newer and much better Regulator chip nowadays.

[YashN]

About the battery pack/charger, after I test it straight to the DAC on its own, it could be interesting to also test it wired to the DAC but also with my DIY LRP on the pack's charging input.

 

I do not know the details of how the internal battery pack is charged or whether it has a trickle-charge option, but I am supposing for the time being that it is so. In that case, I would have that battery trickled charged by the LRP if I let them remain connected.

 

Here again, it will be interesting, or even important, to check how the grounding or ground and chassis continuity between the LRP, the DAC and the battery pack/charger in between these is set up in this configuration.

 

It is a 2600mAH pack if I'm not mistaken, and it is quite small - it is supposed to be carried with you to re-charge your cellular phone without AC when you're travelling.

 

Some good news: my good friend at the nearby second-hand store is back after a long period of break, he was probably burnt out from working too much, so I'll probably have some more good deals there. We gave him our old Blu-Ray player before his break, he was super happy about it.

 

We found a great deal on Blu-Rays today: 10 of them for $25 (CAD), and managed to get some good ones - usually with that kind of deal, you're fairly sure to get titles that nobody wants, but instead I got Mission Impossible - Ghost Protocol, Prisoners, and a few more goodies.

 

The rest of the time, we're saving for Ultra-HD 4K Blu-Rays. So far, the release of new titles seems rather slow, the pace hasn't picked up as much as I had anticipated. It is possible that people are slower than planned by the manufacturers to adopt the new standard.

 

Consumer side, it is OK to wait: you'll get much more affordable excellent TVs this year, a wider variety of UHD 4K players to choose from and this will give some time for manufacturers to smooth out the kinks of their release - there are many, like the Oppo player which people have issues with stuttering and that they are trying to fix with firmware updates.

 

There's a higher-spec of HDMI which is just out as well for even higher bandwidth like 4K @ 120Hz, and therefore, current gear can't support these.

[YashN]

The LM317 is a classic among linear voltage regulators. That surely sounds like an interesting experiment!

 

Good thing and bad thing: the bad side: it's quite old and there are much better regulators nowadays regarding noise, PSSR and stability. The good side: is readily available, very cheap for experimentation, and a lot of people, including the great Walt Jung have explored its abilities, and some have also explored its weaknesses and written about them.

 

So, this is quite interesting to me, because I could definitely just place an order and get a new, much better regulator chip or even a board, but currently, the LM317 is a much better platform for learning as well as making correlations between circuits and SQ. This is quite valuable in fact.

[YashN]

I do not know enough to give good advices regarding linear voltage regulators...except to avoid them with batteries if possible

 

This depends on a lot of parameters: type of battery, behaviour of battery and noise with load, any capacitor used with the battery or not, regulator drop-down, load's voltage necessary to keep its own internal regs within stable regulation.

 

Here is a potential issue with that kind of setup which may give you the wrong impression that batteries should never be followed by regulators: you use a battery which has X Volts, but not enough for the regulator to do its regulation job properly. You then power the load and get bad sound. Normal: you aren't powering the regulator itself properly. If the regulator needs a buffer of say 3V to be kept in the proper stable and clean regulation operating zone, then you'd need a battery which provides that buffer.

It is quite interesting to charge the batteries with a mains LPS. I have been wondering in the past if batteries actually will perform better charged with cleaner power (like LPS), but I could'nt make anything useful out of it. Still a "mystery" to solve! 

 

Technically, it should make no difference at all. I have seen in the past some other technologies where the battery's very charging profile changed with a different charger tech. This shouldn't happen, so people don't get it. Things become clearer when you understand this new setup actually changed the internal structure of the battery.

 

In our usual case, no difference at all for how our battery will behave.

 

Yesterday, I thought I would need to build a new micro-USB cable to power the DAC from the battery pack, but in fact, the out is a normal USB, so I just needed to plug the DAC-side of my connector into it.

 

This worked well: quite a clean sound, looks like attack transient rapidity, cleanliness of mid-range, highs, and bass are all there. Perhaps a little lack of that Elna cap presence and the bass expansion, but the thing with doing things by ear like this, is that you walking on and crossing the fine line between what's neutral and what's euphonic.

 

A second bonus: the battery pack's input power for charging it is actually the micro-USB and the cable that came with it is micro-USB to normal USB, so that can be plugged into the LRP output too! Nothing additional to do here, so I did well by choosing default jacks for the USB Connector and the LRP out too (all USB here).

 

Now, today, what I wanted to test is the potential trickle charge mode, so I connected the LRP to the battery pack, and in this case there's a flashing orange LED which indicates the battery pack is charging (the orange stays ON when fully charged). During normal operation of the battery pack powering a load though, it is a Blue LED which is ON.

 

Unfortunately, while the LRP is plugged in, the battery pack doesn't seem to be outputting enough power: the DAC stops being recognised by the computer. So, hopes of any 'trickle charge' config appear to be dashed with this little battery pack.

 

The funny thing is that these battery packs are not too expensive over at Amazon (or even near my place) but they have been getting quite bad reviews for their intended purpose which is initially to recharge cellular phones on-the-go. Works fine for my DAC though! Bad reviews -> lower price => we get a bargain for our purposes.

 

A couple of these and a circuit to alternate charging and powering the two packs would be a cool project (one which I had for my LifePo4 cells).

 

What is even more intriguing to me personally is battery charged Ultracaps or battery charged LifePO4s. I am trying to learn the basics how to make any of it possible in a future project! [emoji4]

 

Should work well too, but at one point you do need to charge the batteries.

 

I have 6 LifePo4 and some shunt reg for charging them, but haven't gone round to building the charging circuit nor the switching circuit. A bank of 3 should be enough for the DAC, and even potentially for a reg or super reg circuit after it.

 

I have seen a lot of good deals of Blu-ray movies lately here in Sweden as well. Have'nt bought any though since it is difficult to find the time to actually sit down and enjoy a whole movie.

 

It's the best time to get them as they're making way for 4K technology, so they're a huge bargain. The only things that really bug me are the over-use of digital filters - this is really damaging to PQ: colours are washed out, are monochrome or bi-chromic or there's a layer of one colour onto the whole movie. Colour-wise, we are living in the dark ages of Cinema, just at the moment where the technology has improved in leaps and bounds for the home theater...

 

I had satellite TV until 2006 or so when I cut TV, and even movies nearly completely, so I am now catching up. Made-for-TV shows like Breaking Bad and Game Of Thrones rekindled my interest in TV shows, but of course, not many are exceptional. I'm a fan of Nordic Noir movies and shows too. For video, I have worked a lot of making our setup as immersive as possible. I have designed several cool projects for this (some of them yet to be constructed).