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

[bogi]

OK, but have you tried powering the DAC externally completely? And connecting in this order: Power DAC, DAC-side data-line only cable, then lastly, computer-side data-line only cable? Does it work?

 

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

The nicest would be if the 1st schema without ground wire between computer and DAC would be sufficient.

 

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?

[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

[Cornan]

Remember this?

[ATTACH]31978[/ATTACH]

 

My Axing F-plug (SAT) DC blocker arrived today. I plugged it in immediately ofcourse..just before my Supra ground isolator as I have used for some time now.

 

[ATTACH]31979[/ATTACH]

 

In the background you can see my upstream FMC aligned waiting for the DIGITUS fiber cable and my DIY Ethernet (Base100-TX) cable...so my impressions are with AC wireless connection only. My router is still powered by the supplied SMPS plugged into a filtered powerstrip.

 

Did I notice anything? Well YES!!!! I must admit that I did'nt have high expectations to begin with...but the improvements really blew me away. The best invested $4 ever! The sound stage opened up big time and a lot of background details became crystal clear. Amatorski "Soldier" from the EP "TBC" is a track that I have listened to and evaluated probably over a hundred times. I hear the ticking and the intended noise in the track in places I have never heard them before and the airyness of the track is astonishing. The bass is deep yet without distortion. What a great track..and what a great EP!

 

 

I can without a doubt recommend anyone that have F-plug input connectors on their router to give it a try. It is definately something with DC currents coming from the service provider.

I cannot wait to find out if my FMCs really can top this SQ up? More of that later.

 

 

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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!

Even if Supra only specify that there F-CON is a ground blocker it seems that on SAT cables it is also the same as DC blocker as well. So why does Axing improve high frequency and Supra low frequency? This is one of the questions that currently are running inside my head. Bandwidth specs? Return loss specs? Insertion loss specs? Anyway, I'll need to try more of these DC/ground blockers to find the right one I guess!

 

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[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.

[Cornan]

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.

 

Yep! I have quite a few things in the pipe-line right now. Just waiting for the deliveries to arrive (which tends to be annoying as well..especially when delivered from all around the globe).

 

Anyway, so far I have only positive things to say about the ATL mains DC blocker. But do remember that I have a very light load for it. Since my Peaktech isolation transformer was silent to begin with the DC blockers only purpose is to block DC current from the rest of my household. I would say that it made a better improvement that I ever could imagine in that respect. Still, I will perform a test with and without it...but since I want to do it fair and square comparence I must wait for the delivery of a new DH-Lab silver Sonic cable and good quality power plugs. I will report back when those have arrived.

 

When it comes to the F-plug (SAT) DC blocker it is a bit more "complicated". I suspect the DC blocker is actually a ground blocker as well. There is a lot of different specs for those buggers and they are all made for TV/SAT requirements rather than audio purposes which makes it a bit trickier to understand what the specs do for audio purposes. My guess would be that a lower MHz bandwidth rating would cure the low end bass performance, but I cannot be absolutely sure until I've tried. It is just a guess after all.

 

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! ?

 

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[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.

[Cornan]

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.

 

[ATTACH=CONFIG]32098[/ATTACH]

 

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.

I really think that video and audio usually improves by the same things (not all though). It would be fun to try some Hi-Fi tweaks on video to find out if the picture improves. I would like to try my tech IT...but before I do I want be 100% sure I do not create a harmful setup by doing so.

 

I have used AC mains filters and Supra Lorad AC cable for my TVs (plasma only) for many years with great result. 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.

 

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

 

 

Micael

 

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[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.

[Cornan]

Thanks YashN! I will be sure to check "The Salvation" out!

 

After several more evaluations with my both DC/Ground blockers my sound is really much much greater with both inline than with one or none. Thinking about it there might be another explanation to it than just bandwidth. I actually think that there is a possibillity that I am blocking DC currents/leakage loops from my router to my SAT cable and therefore minimizing capasitive coupling along the lenght of that wire. That would explain what my ears are trying to tell me!

 

Since I know that austinpop have ordered two DC blocker I have asked him to try them on each end of his SAT cable as well to see if that theory holds true. Would be very interesting to know since that would also further explain why the router is that noisy...ie. not only to the AC mains.

 

It would also be very interesting to know if someone with two EMO Ethernet isolators could try one at each side of the Ethernet wire to see if that holds true for Ethernet cables as well! ?

 

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[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.

[Cornan]

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.

 

The LM317 is a classic among linear voltage regulators. That surely sounds like an interesting experiment! I heard that those micro-USB plugs is a pain to solder. Personally I failed with the Oyaide DC plugs which is much easier than those little buggers. I do plan to make a new attempt, but only after ordering these "helping hands"

 

https://banggood.app.link/1jsAyRLrIz

 

https://banggood.app.link/rmMw8zyrIz

 

You've gotta love Banggood.com! [emoji1]

 

 

 

 

 

 

 

 

 

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[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.

[Cornan]

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.

 

Indeed! It's a learning curve for everything. There is no better way than to experiment with something that is cheap and reliable. I do not know enough to give good advices regarding linear voltage regulators...except to avoid them with batteries if possible and if you've got to use them make sure they are as close to the powered source as physicly possible and only to use drop-down regulators.

 

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! ?

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]

 

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. Too much time spent on other things. When I finally squeeze in some movie time it is usually Netflix or to the Cinema with my kids. I saw "Sing" at the Cinema today with my 7 year old..and actually got a lump in my throat a couple of times! ?

 

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[Cornan]

Indeed! It's a learning curve for everything. There is no better way than to experiment with something that is cheap and reliable. I do not know enough to give good advices regarding linear voltage regulators...except to avoid them with batteries if possible and if you've got to use them make sure they are as close to the powered source as physicly possible and only to use drop-down regulators.

 

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! ?

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]

 

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. Too much time spent on other things. When I finally squeeze in some movie time it is usually Netflix or to the Cinema with my kids. I saw "Sing" at the Cinema today with my 7 year old..and actually got a lump in my throat a couple of times! ?

 

Great to have a friend that run a electronic store. I wish I had a friend like that. Local electronic stores are almost gone in Gothenburg were I live. Just a few expensive ones left, so my "local" store is Banggood.com, electrokit.com, Svalander.se or Elfa.se these days. A pity! ?

 

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[Cornan]

@YashN

Here is a DIY Supercapacitor battery pack that might interest you. It includes a LM317 linear voltage regulator! ?

 

http://www.instructables.com/id/The-Forever-Rechargeable-VARIABLE-Super-Capacitor-/

 

 

 

 

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[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).

[YashN]

Here is a DIY Supercapacitor battery pack that might interest you. It includes a LM317 linear voltage regulator! 

Yes, saw it when I was researching ultracaps, it's a very cool little project. I don't like the DC-DC booster circuit for audio though, so it could be adapted.

 

The plan is also to build my own ultracap this holiday period and test it at the output of the LRP. It should blast the Rubycon performance to smithereens.

 

Fellow CA member, @hurka built his own 2-bank ultracap circuit for audio - it looks great.

 

For commercial solutions, I have no trouble strongly recommending either the Vinnie Rossi PureDC-4-ever or the Uptone Audio LPS-1.

[Cornan]

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.

 

Yes, there is ofcourse more to it! Quality battery cells is a must as well as choosing the correct voltage for your perticular device you want to power. Far from all devices is not even possible to power by unregulated batteries. It is crucial to understand the actual input voltage requirement of the powered device before choosing the correct unregulated battery. This is a question that the manufactorer support usually do not provide or even knows about and requires some extensive research. When you have found out you want a battery which voltage fully charged is a close as possible to the maximum input voltage of the powered device.

 

 

 

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[Cornan]

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.

 

This is something that I have asked many others on this forum and you are actually the only one except zilch0md (whom I trust very much) that thinks that there is something to it as well! ? I will definately continue to research this matter as soon as I have finished my other experiments.

 

 

 

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[Cornan]

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).

 

Great project! ?

It have been some discussions regarding improved SQ with short DC to DC hard adapters.This would also apply to USB to USB power cable. A hard USB to USB DC adapter might just improve that SQ further.

 

If you've got any pictures it would be very interesting to see them as well!

 

Larry brought up parallel DC cables on the Ultracaps LPS-1 thread. I have been looking into it lately. I want to build my own parallel- and serial DC cables for future needs. Very handy things to have especially with cheap batteries...but also for powering difficult-to-find-voltages or if you'll need a greater mAh rating.

 

 

 

 

 

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[Cornan]

Yes, saw it when I was researching ultracaps, it's a very cool little project. I don't like the DC-DC booster circuit for audio though, so it could be adapted.

 

The plan is also to build my own ultracap this holiday period and test it at the output of the LRP. It should blast the Rubycon performance to smithereens.

 

Fellow CA member, @hurka built his own 2-bank ultracap circuit for audio - it looks great.

 

For commercial solutions, I have no trouble strongly recommending either the Vinnie Rossi PureDC-4-ever or the Uptone Audio LPS-1.

 

Totally agree! The DC-DC booster have to go. It would be very interesting to see hurka's Ultracaps circuit.

 

So far I am struggling to understand how to make an easy unregulated Ultracaps based power supply charged by Li-ion batteries.

Even if I would love to have a LPS-1 or Vinnie Rossi Mini I will need voltages that these cannot provide. My Aries Mini requires 14-18v and I would personally want something in the 16v range (5 x 3,2v) that is not too expensive.

 

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[YashN]

Far from all devices is not even possible to power by unregulated batteries.

 

It is crucial to understand the actual input voltage requirement of the powered device before choosing the correct unregulated battery.

 

When you have found out you want a battery which voltage fully charged is a close as possible to the maximum input voltage of the powered device.

 

Clearly, you have misunderstood, so let me clarify:

 

We were talking about your recommendation about never using a regulator after a battery.

 

I said that you can make mistakes when using a battery followed by a regulator and this can give you the wrong impression about this configuration.

 

Here is a more detailed example:

 

Your DAC needs 5V. So you want to power it with a battery and a regulator.

 

Imagine you choose the LM317 as regulator, as I did for my DIY Linear Regulated PSU.

 

If you put a 5V battery in front of the regulator, and think you can get good, stable, regulated, in short bettter sound from the battery + regulator to the DAC, you won't.

 

What you need to know here is the that the regulator will drop out some voltage for it to be able to work on the regulated output in a stable manner.

 

For the LM317, it is said to work best when there's at least 2.5V - 3.5V to drop.

 

This means, that if you want the regulator to be able to supply a low-ripple, stable, you actually need to feed the regulator a rather stable (5V + 2.5V) or up to a (5V + 3.5V).

 

That is, the supply to the regulator, or in this case, the battery, must be from 7.5V - 8.5V for this configuration to work well and get better, regulated sound.

 

So, in case you have tried a battery with a regulator, and haven't paid attention to the drop-out and necessary buffer to consider powering the regulator, you may have been powering the device out-of-regulation.

 

What that means is that the device can still work (as it may be receiving around 5V but with ripple and noise), but the SQ will not be as good as expected, it can actually be bad if you compare it straight to the 5V battery.

 

So, if you made the mistake of voltage starving the regulator itself because the initial battery voltage was too low, then you could also make the mistake of thinking batteries can't be followed by regulators to get better SQ...

 

This should help make things clearer.

[YashN]

This is something that I have asked many others on this forum and you are actually the only one except zilch0md (whom I trust very much) that thinks that there is something to it as well!

 

Here again, no! There is not 'something to it' - not in the usual charging a battery with an SMPS vs charging a battery with an LRP. You shouldn't have any difference at all. I would be very surprised if you did.

 

If somehow there are still effects related to Leakage Currents in your setup and if you're keeping the chargers connected at all times (which you said you aren't doing), then there could be some differences, but it won't have to do with the battery power itself (assuming the same battery in both cases), but more with the Leakage Current interactions of each charger power supply and other power supplies in the chain.

 

Let's leave it at that.