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In Reply to: RE: Improved Regen sound posted by jkeny on November 22, 2015 at 13:43:48
i'd just like to make a few 'notes' on batteries and Lithium chemistry in more particular.
It is important to note 2 things. Lithium and Lithium ION batteries are 2 different categories.
But in EITHER you will have a choice of several chemistries. This leads to one major, common outcome. You will have a wide choice of Cell Voltage to deal with. The Lithium Polymer with very high energy density typically has a cell voltage of 3.7 volts. So, a '3 cell' battery will be 11.1 volts fully charged. These batteries are also rated with a 'C' value which somehow reflects the ability to discharge very rapidly. Some of the hobby motors used can Easily have in excess of a 40 amp draw. A low internal resistance battery is ESSENTIAL.
Some other lithium chemistries are both higher and lower voltage. Some are low enough to be used as direct replacements for your good old Alkaline battery.
A little research on the part of those wishing a battery replacement should yield some good results. I'm certain that a low internal resistance battery which is also low noise CAN be found.
One in particular, a Li-SOCl2 chemistry is good in VERY cold conditions. This battery, if kept cold MAY also have lower noise? Call it about 3.5 volts in use. I have NO idea how to 'refrigerate' a battery in-use.
Some lithium cells are and some are NOT rechargeable. Don't try to recharge a single-use cell or you might have a problem.
The Hobby Shop types sell a recharger BAG to contain any potential problems when recharging your Li-ion battery and some of the chargers are VERY smart, indeed, even capable of 'balancing' the voltage between cells.
In some of the above posts, I see reference to both a 5v and 3v regulated PS. This, I think, means you need a battery to supply a higher voltage then than highest output voltage you wish.
Too much is never enough
Follow Ups:
Thanks for all the info on various batteries but what we are focusing on here is LiFEPO4 batteries which have a steady voltage of 3.3V until they reach their low charge point when they quickly fall to their minds V of 2.7V
It's important not to confuse this battery chemistry with other s
Lithium Iron Phosphate is one of the older Lithium ION batteries.
A search of other chemistries will show many (several?) which have similar discharge curves.
If the voltage does indeed have a REGULATOR, than is doesn't matter as long as the voltage is a certain amount OVER the desired regulated voltage. Did I read some complaints about noisy regulators in this thread?
Some of the newer chemistries are available in size '18650' of which the Tesla uses THOUSANDS per auto and are maybe the swiss army knife of batteries. Available now in up to 5000mah with stable voltage during much of its capacity. Voltage starts at 3.7v
The reason I suggest that particular cell, is that you can buy 'em WITH a little charger, keep a spare pair charged so you NEVER go flat and the low self-discharge means long shelf life. i do not know the spec for internal resistance or any noise issues with this cell.
Too much is never enough
Thanks again, Pictureguy, you seem to have a good knowledge of battery chemistry. What we want to avoid is a regulator on the battery output. Can you nominate any others that have 3.3V output & a similar discharge curve to LiFePO4 batteries?Regulation from my experiments so far, have proven to be noticeably detrimental to the sound when compared to using power from the batteries directly.
I've mostly used these batteries on digital ICs which require 3.3V power. I'm not sure if it's the low noise (especially at LF) or fast transient response that accounts for their advantages in this role? The only regulators which seem to come close to these batteries are the Paul Hynes ones so it's possible to build. He has different regulators for different roles, digital or analogue power, low current or high current & he emphasises transient response for digital but I would also add low noise at low frequencies as also being important for clocks, etc. These batteries seem to check both of these boxes
I've also tried them on smallish, chip-based power amplifiers & the improvements were also noticeable
Edits: 11/23/15
I'm getting out of my depth, but have you considered fabricating a DISCRETE regulator? Maybe thru the use of a Zener Diode?
I'm certain that someone who KNOWS can help you with this.
As for batteries? You'll have to go to the next level thru some research.
As a start? Simply GOOGLE 'lithium battery' or 'lithium ION battery'. The Wiki would be where I'd start. Keep in mind that things change LOTS and quickly, so such articles may not be up to the second.
Too much is never enough
Huh??
You seem to have the wrong end of the stick, here.
Why do you think I might want a discrete regulator - these batteries perform better than any regulator I've tried - the only regs that come close are the Paul Hynes ones which are very much more expensive than a battery.
Thanks for all your input on batteries so far but I was hoping you might have been able to answer the question I asked - what other battery chemistry will give 3.3V & the same discharge slope as LiFePO4? I'm not particularly looking for a replacement for LiFePO4 batteries but as you say yourself - with regard to information "Too much is never enough"
This'll be my last post on the subject.
PLEASE, by all and any means, try the WIKI on Lithium Batteries. Find a cell with higher than required voltage and Than see if you can dig out the discharge curve. I've got lots on my plate (so to speak) and while I'd love to get into the minutia of your dilemma, I simply don't have the free time.
A few sources for discrete regulator information may be either DIY Audio or perhaps Elliot Sound Products. Paul Hynes didn't INENT this category, but does it well.
If you are interested in 3.3v OPEN CIRCUIT, I don't offhand know of an exact match. Some are higher, some are lower.
Knowledge of the tolerance of the circuit may also help choose a battery. Some electronics may work at -+0.2v given a 3.3v nominal. Something along those lines:
Too much is never enough
Hey pictureguy, again you seem to have the wrong end of the stick - maybe you are reading too fast & not comprehending? Your replies, although they seemed to promise a knowledgeable source of information on batteries, now seem more confusing than enlightening.
I don't have ANY dilemma - I find the LiFePO4 batteries perfect for my requirements & perfectly suited to the PS roles I have used them in. A 3.3V open-circuit is perfect using these & provides substantial advantages.
I don't believe there are any alternatives which match the characteristics of LiFePO4s & you seemed to hint at knowledge of this area but no worries.
Thanks anyway for your input
You want someone to TELL you what you need to know.
I want, or would desire you, to do some research. Everything is out there for your reading pleasure.
If you are happy with the current (no pun intended) situation, why bother to write?
Too much is never enough
Wow, you really do not comprehend my post sor what the thread is about, do you?
Sure, easy.
You don't like regulators and have replaced it with a battery which to you sounds much better.
So what? You mentioned some guy who I looked up and he does make some neat looking discreet regulators. You said they were too much $$, even though a fixed cost rather than a recurring cost of battery replacement and the hassle of recharging. I get the impression you think THOSE sound OK, or is that mistook?
Now what?
Too much is never enough
So this is why this place is called the "asylum" !!
Edits: 11/24/15
More subjective comments: after listening for 7 hours I am convinced that timbre has never been better in my system. This is especially noticed on good piano recordings. Almost lost is the superb bass: tight yet full. The other thing is air around everything. It is really enjoyable to have such a major impact on sound from just knowledge (thanks Jkeny) and minimal work. Can a single Regen be even better?
Thanks for the reprt, Theob - yes they are all the SQ characteristics that I have heard with this tweak.
Can a single Regen can be better? I suspect so but only trying it will sort this out
I will get there its just a matter of time. Other obligations in this US holiday week.
Sure, I wasn't pressurising you, just answering your post
No offence taken.
One more comment on the sonics. All instruments seem to emanate from a smaller space within the larger acoustic. As a result the imaging is phenomenal. Especially in a well recorded classical piece. I have one of those Spring music...4 Seasons et al.... files. One cut is a Vivaldi movement for mandolin and orchestra. You can almost guess the distances between instruments. You see the space.
Edits: 11/24/15
theob,
I would love to see a photo of your Regen board wired up with the bypass. Not that jkeney's original board photo and very clear descriptions won't get the job done, but things always feel better with a photo of the done deal.
Thanks Guys.
Send me an email
Chopper87@aol.com
Thanks a bunch! I just finished ordering some of the batteries and an appropriate charger. Your photo/s will help my confidence that I am doing it correctly.
Lance A
theobetley@gmail.com
My theory is that the solidity of the soundscape is the result of the lower low frequency noise of the battery & the resultant lower close-in phase noise of the clock but it's only a theory
I don't doubt the perceptions, but the theory seems somewhat incomplete. The problem is that the clock is the USB bit clock. Phase noise has nothing to do with phase noise modulating the audio clock, because this clock is at a totally unrelated frequency. A possible theory might add that the regulator noise caused jitter in the USB bit clock affects the USB receiver circuitry's power consumption. This is related to John S's theory of how the REGEN works to improve sound quality, but as far as I know this is just speculation as there is no hard evidence of what is going on.
We do know that noise on the REGEN power can be coupled into the analog output of some DACs in the form of common mode noise. This noise appears at the packet clock rate (8 kHz), indicating that the regulation isn't sufficiently stiff.
It beats me why DAC designers don't deal with these issues. There is no excuse for any 8 kHz noise to appear in the output of any USB DAC, regardless of the input signal, assuming only that the input signal conforms to the USB specification.
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
Why the usb interface is used without recognising the noise problems?
Yes, Tony, sorry my theory was a more general observation about what the characteristic improvements in SQ I have perceived Vs what I believe is the underlying cause of them.I find that the solidity & pinpoint placement of instruments in soundstage seems to emanate from reduction in close-in phase noise although I haven't measured this. However, what often accompanies such reduction in phase noise is also a reduction in the playback system noise. So these two factors are often interwoven & difficult to separate. The reduction in general playback system noise gives an impression of better realism to the sonic illusion.
Now, how exactly these two possible mechanisms are the result of using the Regen & improved by the battery tweak, I'm not sure - it seems to me that improving the digital signal does result in improved sonics but by what mechanism, I'm not sure. My simplistic thinking was that improving the PS to the USB clock was contributing to a better formed USB signal waveform being output from the Regen. Of course improving the Regen's PS also reduces noise on the output signal of the Regen. So, again we have an intertwining of mechanisms.
JS's speculation on how the Regen works was dealt a significant blow, in my mind, when JW (John Westlake) revealed that there is no ramping up of current in the USB PHY when dealing with progressively worsening signal integrity of the USB signal - no such mechanism exists in USB 2.0 receivers, only in USB receivers designed to handle USB 3. So, although I was initially a supported of the JS theory of operation - it seems less accurate to me now
But then theory is great but observation comes first or as an ex prime minister of ours used to say - that works in practise, now let's see if it works in theory :)
As regards CM noise - it's a lesser known issue on USB audio devices - most designers only consider differential noise & conclude that the differential USB receiver will take care of that, mistakenly, in my view. CM noise just isn't often on their radar
Edits: 11/25/15
In these days of rapid accumulation of knowledge in just about everything, it seems that we are even less capable of resolving mutlti parameter issues in software/hardware performance. In fact, the reverse is the case in that we now seem to latch on one thing or another, and simply speculate.
You might not know who JK is. I think he REALLY knows what he is talking about, and does not need any help. :)
Since you posted the in depth post on batteries maybe it was thought you had a direct relationship with the Energizer Bunny and could reveal some trade secrets, not just reference Wikipedia.
Regards
Bob
Wouldn't know JK if he ran over me in a crosswalk. Am I supposed to know him?
I was trying to simply help him find a better battery. Battery measurables include internal resistance and of course the voltage / output curve which for JK's purposes, needs to be as flat as possible. Given the huge number of Li and Lion chemistries, I'm not about to plow thru it looking for what is probably a marginal improvement, though you could get lucky. The battery chemistry which JK uses is from the 'dawn' of the Lithium technology and may have been bettered in ways that matter to HIM.
Too much is never enough
Where did I say I was looking to find a better battery??
what constitutes an improvement in SQ and is a battery really better than a good regulator?
When feeding a circuit with a battery, there is self noise from the battery itself to consider, if there is no further bypassing. There is little information of practical use in audio that I can find wrt LiFePO4 battery noise in this regard.
I don't think that one can say for certain that battery power is always superior.
I was in a dealer demo room which had several LiPO powered usb to I2S hdmi converters lying around. I asked why and was told that that the batteries had all failed. This was in spite of a clever self activated inbuit charging circuit.
The manufacturer has recently abandoned this design and had gone over to dc power, with an expensive super capacitor reservoir unit as an accessory!
When one trickle charges a battery which is providing power, there is the situation where discharge and charge chemistries are taking place at once. Is this good? Who knows.
"what constitutes an improvement in SQ and is a battery really better than a good regulator?"Your question would be answered by listening!
"When feeding a circuit with a battery, there is self noise from the battery itself to consider, if there is no further bypassing."
At such low currents as are drawn by digital ICs (usually in mA), the self noise is likely to be very minimal from a battery that can deliver 60Amps continuously & 120Amps instantaneously.
"When one trickle charges a battery which is providing power, there is the situation where discharge and charge chemistries are taking place at once. Is this good? Who knows."
Try it & see if it affects SQ.
As to long term reliability of batteries - just look at electric vehicles which use exactly the same batteries - are they reliable?
But I like your approach to issues - look for the weaknesses first - it's the approach I use too!
Edits: 11/23/15
I have ordered the batteries you suggested, but this doesn't stop the mental questioning. Battery noise is not a function of battery capacity and is a function of chemistry; the smaller the current draw, the more significant it is likely to be as a percentage of output.
How long does one of your recommended batteries last if one does not trickle charge?
"I have ordered the batteries you suggested, but this doesn't stop the mental questioning. Battery noise is not a function of battery capacity and is a function of chemistry;"
It's a function of both - look at the TNT you alluded to about battery noise
" the smaller the current draw, the more significant it is likely to be as a percentage of output."
You can keep doing mental questioning but why not wait until you get the batteries & your questions will be answered empirically?
"How long does one of your recommended batteries last if one does not trickle charge?" I haven't tried one on the Regen but you can figure this out mathematically or empirically
"I have ordered the batteries you suggested, but this doesn't stop the mental questioning. Battery noise is not a function of battery capacity and is a function of chemistry;"
It appears that larger capacity batteries of the same chemistry have lower noise. This is what one would expect. Simply paralleling identical batteries will reduce the noise due to cancellation.
A little googling found a reference that supports your claim that larger capacity batteries are going to have lower noise.
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
If you read the paper correctly, it is the internal resistance related to larger capacity batteries that leads to lower self noise, and on it's basis, one would use NiCads with their lousy self leakage and life issues that should be tried.
Papers like these often lead to untested speculations.
And what is the internal impedance of these A123 LiFePO4 batteries, then?
You are the expert, you tell me.
There is no collated information on the performance of batteries in audio other than the TNT stuff and uncorrelated posts.
I used batteries as early as the 1970s and every piece of battery powered audio gear I have had had posed operational and longevity issues. Note my post about the latest and expensive battery powered usb to I2S spdif processors (LiPO nano Technology quote) I found lying about in a dealer's demo room!
Ah well, if you don't find this approach of much interest to you then it isn't for you - no talking will change that but I thought you ordered some LiFePO4 batteries so I'm confused by your mixed messages??
You need to read and understand my posts before making points such as these.
I did not say that battery power is no good; I said that there wer problems also and that altering other play back components also have as much effect as using battery power ie SQ is a multi parameter characteristic.
I have read your posts which seem to throw up quite a lot of speculative reasons for not using batteries - most of your speculation is based on uninformed sources of information so I wouldn't elevate them to the phrase you used "reasons for not using batteries".But I look forward to your impressions of the use of these LiFePO4 batteries in this particular application
Edits: 11/26/15
I speculated as much and as little as you have.
Much of what I said has been based on 20 years of using batteries for audio and on other people's experience (including dealers).
Posting links to a few academic papers on some batteries and zooming in on one or two sentences isn't a basis for promoting it's use (or otherwise).
I've been using these particular batteries for over 5 years now in various digital & analogue devices so I have some direct experience from which I'm speculating. What started off as a seemingly healthy sceptical view seems more like a deep well of negativity.
But I don't want to enter a pissing contest with you - just let us know your impressions when & if you do the tweak.
My general experience with regard to batteries has been similar to fmak's. The have been nothing but a PITA in various applications. However, I have not tried the latest battery technology (unless it is hidden in one of my portable devices and so far, none of these has shown any miraculous properties as to reliability). In the past I had some really harsh demands on my batteries, namely powering avionics in my sailplane at high altitudes when it is very cold.
One thing I would like to see is measurements of noise on the output of the battery when it is being attacked by the type of load generated by computer logic (e.g. CMOS) where there is huge spikiness of the load at various frequencies depending on both hardware and software. I suspect this requires bypass right near the load, in any event since the inductance of the wiring between an ideal battery and the load would still leave noise.
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
I agree and this is good practice.
To categorically say that no additional bypassing should be done when powering a usb chip thru a battery is theoretically and practically unsustainable. And to add that trickle charging by a power supply at the same time does not affect the operation or SQ is suspicious. All other battery power devices I have come across disconnect the charging power source when playing audio.
I actually get a big improvement in SQ powering the Regen with a 7.4V LiPO battery that should last for a long time.
In the days to come I shall directly power the Regen with a 3.3V LiFePO4 battery and a 3.3V Jung type regulator with preregulator, and compare/post sonic impressions.
My recent encounter with a major dealer's dead LiPO nano powered devices was a reminder that battery supplies do not last.
Anybody with half a brain cell left intact would know that there are bypass caps at the load i.e. at all the power pins of the USB Hub chip & on the PS input pin of the clock.In this thread, I am giving my long experience in using these batteries with chargers - you can be suspicious all you like about this but experience counts for a lot more than uninformed speculation.
I'm sure the people who try this will be able to report on the other thread who is correct & who is uninformed.
Edits: 11/27/15
Is 20 years longer than 5 years? What education and training in electronics do you have?A small capacitor next to the usb chip serves only as local hf bypass. Half a brain should know this.
You are advising everyone to bypass any of the protection afforded by the power supply chip in the Regen, and run an unrestrained high current dc supply into someone's expensive usb dac with no caution at all.
From a manufacturer, this is unacceptable advice.
Edits: 11/27/15
Are you trying to say you have 20 years experience using these LiFePo4 batteries - that would be some claim as the technology wasn't available to the public, 20 years ago.Why not plague some other thread with your BS or has everybody already cottoned onto you & ignores you?
It would seem that is the prudent thing to do - bye!
Edit: I see you edited your post since I replied. Yes local HF bypass is all that's needed. The battery itself acts as a very large capacitor with very low internal impedance & capability of delivering gobs of current as fast as required. The move of digital to lower voltages has resulted in higher current spikes & these batteries answer most, if not all of the requirements required for a good digital PS.
But then I expect you will come up with more BS speculative issues & snide remarks which will be ignored
Edits: 11/27/15 11/27/15 11/27/15 11/27/15
The issue I have with trickle charging the battery while listening to music is that there remains a potential coupling path for power line noise. This may or may not be a factor in any given environment, but it is at least a potential confounding variable and source of frustration.
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
Sure, Tony, I had the same thoughts when I first started on this journey with batteries - until I tried it :) They seem to also act as very large capacitors - capacitance in the Farads. The distinction between capacitors & batteries is becoming hazy - with Lithium capacitors 40F to 270F - the new term for these are energy storage devicesOthers have found no audible difference between charger connected or not in various configurations with various chargers & at least one poster here has reported the same - theob, on the other thread.
Edits: 11/27/15 11/27/15 11/27/15 11/27/15
Well, I started this thread to allow people investigate these batteries in this particular application. I can assure you that it improves the sound quality of the Regen many fold - much more than the difference between different PSes powering the Regen through its DC input.
I can also assure you that these batteries have been used on motherboards in the areas you mention (memory being one of the spikiest current devices) to great effect. Measurements - no? Audible differences - yes!
Did anybody read the paper I linked to?
Although it didn't specifically investigate the noise of this battery chemistry it did draw speculative conclusions based on the range of batteries it measured - namely the capacity of the battery had a bearing but particularly the internal impedance was a major factor in the noise of the battery.
As I asked Fmak before, did he know the internal impedance of these LiFePo4s. If anybody reads that paper I referenced & understands it, they will see that the internal impedance is the critical factor in both voltage noise & current noise of a battery.
So my question to Fmak was to check if he had done any research into these batteries or were his speculations based on uninformed guessing. The batteries are measured at below 8 milliohms internal impedance from which you draw your own conclusion
As to noise measurements - I doubt you will find any in the applications you
that 8 mOhm internal resistance is what makes a battery tick a sonic high.
As an audiophile I live for the days when I have a good powerline. On these days one can really assess if a tweak really is an improvement. Yesterday was such a day . I listened all day long until it ended. It was really a lot of fun. I can assuredly tell you that this tweak is magnificent.
Yea, it remains to be seen if others try this or if the naysayers frighten them off or others try it - time will tell
Hey, my parts are on the way. I will offer a clear objective and unbiased opinion of this upgrade/modification. I have NO friends or enemies here, no axes to grind. Although I am hoping for a marked sonic upgrade.
Lance A
Best to post on the listening impressions thread - this one is probably scuppered!
Maybe I should just make a post on this thread to bring it to the top of the list & act as a magnet for those who are compelled to post "noise" - consider it like one of those ultraviolet fly zapper traps?
Yes, Tony & if Fred or any others want to delve into battery noise measurements, they should leave that TNT article alone & look at some real research from NIST (national Institute of Standards & Technology) here:
http://tf.nist.gov/general/pdf/1133.pdf"In this paper a measurement system capable of measuring voltage noise below -200dBV/Hz is discussed & it's ability to characterise experimentally high performance voltage references is explored. The results of such measurements on common batteries are presented......"
Unfortunately, LiFePO4 batteries are not covered but it does show an inverse correlation of noise to battery size - the lower noise comes from larger batteries
But here are some measurements on LiFePO4 batteries which might be of interest - no noise measurements but internal impedance measurements given if I could only understand Nyquist plots of impedances!
Edits: 11/25/15 11/25/15
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