ESS Saber DAC

[Deleted]

Oct 9, 2010 12:01:59 GMT jkeny said:

Alex,
I've said it to you privately but maybe worth repeating it publicly - that is not the max working V 4V is the absolute max; 3.6V is the recommended max. The LiFePO4 batteries (not LiPO) when fully charged are 3.7V but you can discharge them back to 3.3V within seconds before operation if it worries or just charge them up to 3.3V. They really don't work any worse at 3.3V than at 3.7V.

Not all batteries are the same & your trial with Ultimate Li batteries will reveal what Li Ultimate batteries sound like in your system - nothing more - results good or bad cannot be generalised to other batteries. It may well help ground loop or RFI issues but that is perhaps all that can be generalised.

The series impedance will be a little higher than with the LiPo , but still should show if the battery area is worth further investigation in this area of the SC DAC ONLY
.Regards Alex.

John
I don't give a rat's anus about what the maximum a DIR9001 I.C. can take. What the data sheets say there is -0.3 to +4v.
The recommended maximum working voltage is +3.6V.
The manufacturers specify these figures for very good reasons.
You are far too close to the subject of the LiPo batteries because of your commercial interests in respect to their use with your modified versions of the HiFace.
Do not treat me as if I came down in the last shower !
Of course I am aware that not all batteries are created equal.
I clearly stated to you privately that the results i obtained would apply to the SC DAC ONLY. (above)
Alex

[jkeny]

Hey listen, Alex, no need to attack me - I just posted to get others opinions on this - I'm certainly not treating you as a neophyte but some of your statements are incorrect - recommended max is not absolute max; LiPo (4.2V max) is not the same as LiFePO4 (3.7V max); the results will apply to the Li batteries only (what type are these?) & cannot be generalised for the reasons I stated. What is the internal impedance of the batteries you will be using?

Please don't throw commercial blah blah at me if I correct your errors - I happen to know something about these batteries! Why not attack PH for having commercial interests when he posts about regulators? I get fed up with this sort of selective shit!

[Deleted]

John
My PM to you was conciliatory, as you appeared to have got the impression that I was dismissing your reports about these batteries.
I will state again that I investigated the possibility of trying them with the DIR9001, but decided against it because of my reluctance to exceed the manufacturer's recommended maximum working voltage of 3.6V. IF I had noticed even the most trivial of improvements over what I am using now, I may very well have tried the batteries that you recommend, but ONLY after ensuring there was no possibility of >3.6V being applied when in circuit.
You also appear to have mustered the troops in an effort to discredit Leo after his report about these batteries with HIS Buffalo DAC, which is VERY different to the vast majority of build of these DACs.
I suggest that we both cool off now.
It is 1.12AM here now, and I am shutting down.
Alex

[jkeny]

I said I wasn't going to post here in deferrence to PH & his business but this is not tolerable - I won't let accusations like this stand, even if you are going to bed.

Firstly, I didn't "muster the troops" I had already notified Dan way back as a matter of courtesy that I was quoting him in my posts here & to get his approval about doing so. Go & check back on the thread before posting - enough of the jumping to conclusions!

I don't know grottojones!

Just because people post positive experiences of using these batteries doesn't mean that there are two camps now - just take the individual's posts at their word - their experiences, same as you do with Leo's post.

I said to you that you can charge the batteries to only 3.3V without any problem & they will not perform any worse than if at full charge. I even offered to send you a battery charger schematic.

You put up all sorts of rationalised excuses why you wouldn't try them - so if you are really serious about trying them what's your problem? Otherwise why are you posting about some other battery test that you are going to perform - how is that relevant to these batteries? Do you not think that introducing a test on different batteries on a different DAC is simply going to confuse & muddy the focus that has been shown so far?

BTW, getting back to something you said about the impedance of these batteries RISING up at high frequencies as you interpreted Leo's tests suggested. I sent you scope shots a while back showing the effect of using these batteries on the SPDIF waveform of a Hiface. In it I pointed out & it was clear on the pics that the rise time of the transition slope was substantially faster when using the batteries. Would this have been possible if the battery impedance was HIGH up in the GHz range where the speed (4nS) of this slope is located?

So my impression is that you are the over sensitive one when it comes to this topic - making all sorts of unfounded accusations & being particularly defensive about it. What gives?

[dangiovanni]

Oct 9, 2010 8:38:54 GMT leo said:

I've tried various versions of the Flea including alterations to make it 3v3 output, very surprised at your findings in all honesty.
Anyway as long as people are happy , I've gone to the trouble of faffing about adding and removing parts with the batteries, at the end of the day I still prefer the regs , I don't see what the problem is.

I don't have the slightest problem with your results Leo, and never have had. Your results are a little different to mine, fine. But I've felt no need to undermine your results via frankly silly criticisms of your testing methodology or the resolving power of your system. This is what sandyk and Paul Hynes have done.

[dangiovanni]

Oct 9, 2010 9:56:22 GMT @sandyk said:

Perhaps that is because on many occasions, what Leo has reported hearing has been confirmed by several other RG members ?

That's irrelevant. There are two slightly different set of results. The set that isn't liked is undermined.

Oct 9, 2010 9:56:22 GMT @sandyk said:

Even the types of diodes used in the PSU area has an influence, with several RG members now reporting (me included) that the faster SF12 and SF14 series, lifts a veil in comparison with the much touted UF400x series.
Things like that may well have an influence on the amount of HF rubbish that gets through, to sometimes make the Paul Hynes regulators seem a little "splashy " ?
SandyK

Reasonable thoughts, except that you have no idea what my chain consists of in regard to Leo's, or anyone else's. As it happens I have multiple layers of filtering/snubbing/regulation prior to the final regulator. My speakers also have high quality ribbon tweeters, so perhaps my system is resolving things that most hide? Who knows?

But this is a pointless line of reasoning - it leads to a pissing contest over who has the best hifi, and they are the ones who's results count. See how silly it is?

[jkeny]

Seeing as Alex brought this up. Let's get everyone to lay their cards on the table - how about everyone here declaring anything that might be causing them a conflict of interest in this whole scenario so readers can fully evaluate the posts!

Alex has already stated that I use the batteries as part of a modified Hiface which I sell, PH sells the regs to which the batteries are being compared. So we both have a bias that people can judge for themselves. Dan Giovanni, Grottojones, Sandyk, Leo - anything to declare which might be relevant or which readers should know about?

[dangiovanni]

Oct 9, 2010 15:45:42 GMT jkeny said:

Seeing as Alex brought this up. Let's get everyone to lay their cards on the table - how about everyone here declaring anything that might be causing them a conflict of interest in this whole scenario so readers can fully evaluate the posts!

Nada for me. I wrote an article for HiFi World god knows how many years ago on jitter and building clocks. Got paid a book on acoustics. That's the closest I've ever come to making a penny out of hifi

[paulhynes]

Hmmm. Looks like things are getting out of hand.

Actually I am trying to stay neutral on the issue re batteries verses regulators until I have had the chance to try/measure some of these LiFePo4 batteries though I will stand by my statement that testing mains driven regulators (any regulators) against a battery source is not a level playing field for the regulators. My statements so far have been general, relating to technical issues and valid testing procedures and not specific to my products. I was a Research Chemist for eight years of my earlier life and we tend to get a little fastidious about testing procedures. These are just my opinions and others may differ in their opinions. This is OK. Posting on the forums invites discussion but lets try and keep this from getting edgy.

Grottojones experiments were all battery driven and would be more meaningful than the mains driven regulator test. His offer to attempt some impedance measurements on the batteries is good too, as it will benefit us all to know more about this.

I have known Leo for a while and respect his attention to detail when doing audio comparisons. He is also keen to find the best performance for the Buffalo DAC power supply. If this means using batteries then this is what he will use. In my experience he tells it how it is.

Regarding the issue of low power supply output impedance. I agree that this is not always maintained at the load due to pcb tracks and wire connections with their inductive and capacitive effects. However I do not see this as a reason not to attempt to reduce the power supply impedance to the lowest level you can. As an example, assuming you have a regulator with say 10 milliohms impedance at a given frequency and the wiring to the load adds a further 10 milliohms, the overall impedance will be 20 milliohms, which, as far as the load is concerned, is the power supply source impedance. Reducing the output impedance of the power supply to 1 milliohm will give an overall impedance of 11 milliohms. I have to say that, from experience, that nearly halving the impedance of the power source (including wiring) will provide a noticeable reduction in load/power supply interaction, the results of which are usually very audible in high-resolution systems.

I asked John Kenny for information source validation, which is hardly a personal attack. For anyone who feels that they have suffered a personal attack from me, on this forum, I am open to discussion about this. All you have to do is tell me why you think this is the case.

Regards
Paul

[jkeny]

Paul,
This thread has become dialectic - splitting into two camps, rather than an open debate to discover which is best sounding on the Buffallo in the AVCC role. I'm afraid that those presenting their positive experiences with the batteries have been questioned & queried as to their system & it's shortcomings (& their motivations, commercial interests, etc.), whereas the same criteria have not been applied to the negative experiences. So one can easily see how this has given rise to the view that this is less about an impartial seeking after the best PS in this AVCC role.

I can understand your view that comparing mains driven regs to battery is not a level playing field but is that not what we are talking about? The mains driven PH regs is the standard configuration in which your regs are used, no? So mains driven PH regs Vs LiFePO4 batteries is a relevant comparison?

If the PH regs need to be driven by battery power to give of their best then that is new information that I haven't seen the multitude of PH reg users knowing about - indeed it seemed to come as new information for Leo too. So I'm not sure what to make of this!

I agree that grottojones tests on these batteries will be interesting as will yours. I PMed him along these lines. As I said I sent some scope shots to Alex already which might provide some evidence of the batteries performance up at the GHz range.

[dangiovanni]

Oct 9, 2010 16:07:53 GMT paulhynes said:

I will stand by my statement that testing mains driven regulators (any regulators) against a battery source is not a level playing field for the regulators. My statements so far have been general, relating to technical issues and valid testing procedures and not specific to my products.

Hello Paul. I first tested your regulator against three active parts, and found it to perform very well. Testing against a battery does change things as you point out (something I have already pointed out myself twice). You have to compare two systems. The battery is a very simple system, the regulator includes everything upstream of it up to the national grid, although I'm sure you would agree the battery is the dominant part in terms of performance. It is completely valid to compare the two systems, as long as one is aware that one is doing that. Note that Leo also compared the two systems (just as I did), posted his results, and no-one complained about testing methodologies.

Oct 9, 2010 16:07:53 GMT paulhynes said:

I was a Research Chemist for eight years of my earlier life and we tend to get a little fastidious about testing procedures.

I'm a software and systems engineer and completely agree.

Oct 9, 2010 16:07:53 GMT paulhynes said:

I have known Leo for a while and respect his attention to detail when doing audio comparisons. He is also keen to find the best performance for the Buffalo DAC power supply. If this means using batteries then this is what he will use. In my experience he tells it how it is.

I have no problem with that, although it has to be accepted that his results are entirely subjective to his tastes and his system. As are mine, of course. I try to be as objective as I can, and do occasionally do measurements of my system. I always listen for transparency above musical impression, as otherwise one can get lost it trying to get a specific emotional response to the music (not that that's bad in itself).

Oct 9, 2010 16:07:53 GMT paulhynes said:

Regarding the issue of low power supply output impedance. I agree that this is not always maintained at the load due to pcb tracks and wire connections with their inductive and capacitive effects. However I do not see this as a reason not to attempt to reduce the power supply impedance to the lowest level you can. As an example, assuming you have a regulator with say 10 milliohms impedance at a given frequency and the wiring to the load adds a further 10 milliohms, the overall impedance will be 20 milliohms, which, as far as the load is concerned, is the power supply source impedance. Reducing the output impedance of the power supply to 1 milliohm will give an overall impedance of 11 milliohms. I have to say that, from experience, that nearly halving the impedance of the power source (including wiring) will provide a noticeable reduction in load/power supply interaction, the results of which are usually very audible in high-resolution systems.

The effect of output Z will depend largely on the load that the circuit being powered is driving. A low output Z in a regulator will hint not only at good load regulation, but good line rejection, due to their both being linked to loop gain. So for example, if improving output Z increases sound quality despite a constant current load, it's likely that it's the line rejection at play. A battery of course has infinite line reject, so to speak. There is also the issue of self noise that will effect performance, and may dominate other factors, as may earth leakage currents. The reason I mention this is that there is no reason to assume that 1 mOhm Z power source will sound better than a 10 mOhm one, as sandyk seemed to be hinting at earlier.

Oct 9, 2010 16:07:53 GMT paulhynes said:

For anyone who feels that they have suffered a personal attack from me, on this forum, I am open to discussion about this. All you have to do is tell me why you think this is the case.

Regards
Paul

I wouldn't say personal attack, but you did criticise my testing methodology in comparison to Leo's. I hope I have been able to address this. I was more irritated by the argument which reduces to "your results are wrong 'cos there's something wrong with your system" which surfaced elsewhere. It's a tiring argument which pops up too frequently, and leads nowhere (except irritated people).

Also, I think that sandyk using "commercial interests" against Jkeny is not consistent with allowing you to express yourself. Surely everyone or no-one gets to have their say.

Finally, If I was looking for a simple drop in solution for improving supply quality, I would likely use one of your regs (in fact I currently am).

[leo]

Oct 9, 2010 14:38:35 GMT dangiovanni said:

Oct 9, 2010 8:38:54 GMT leo said:

I've tried various versions of the Flea including alterations to make it 3v3 output, very surprised at your findings in all honesty.
Anyway as long as people are happy , I've gone to the trouble of faffing about adding and removing parts with the batteries, at the end of the day I still prefer the regs , I don't see what the problem is.

I don't have the slightest problem with your results Leo, and never have had. Your results are a little different to mine, fine. But I've felt no need to undermine your results via frankly silly criticisms of your testing methodology or the resolving power of your system. This is what sandyk and Paul Hynes have done.

Thats ok, I was out all day so my post was quick just before leaving, hope you didn't take it the wrong way.

The Flea is ok but didn't work great for me setting it to 3v3 for the AVCC, my scope is only 60mhz but it showed some slight ringing when used with the Buffal032 . Maybe the chosen error amp wasn't suited to either the AVCC's load or the reduced 3v3 output, I dunno. Its the only reason I mentioned I was surprised with your results. The sound to me wasn't right which is why I scoped it to check for problems

Edit, When I say wasn't right, it was a slushy effect in the high's

[leo]

Oct 9, 2010 9:56:22 GMT @sandyk said:

Kinda disappointing - no-one is subjecting Leo's experiences to a similar type of scrutiny.

Perhaps that is because on many occasions, what Leo has reported hearing has been confirmed by several other RG members ?
I wouldn't be surprised if the reason that designers such as Paul Hynes and Russ White have become members here, is because the findings and reports by Leo have also been widely accepted in DIYAudio and other forums. Still, when you get down to the incredibly high performance of DACs like the Buffalo series after modifications , in comparison with earlier popular DACs, it shouldn't seem surprising that other areas of the chain will be shown to have a marked influence on the listening experience. Even the types of diodes used in the PSU area has an influence, with several RG members now reporting (me included) that the faster SF12 and SF14 series, lifts a veil in comparison with the much touted UF400x series.
Things like that may well have an influence on the amount of HF rubbish that gets through, to sometimes make the Paul Hynes regulators seem a little "splashy " ?
SandyK

P.S.
I will not use the LiPo batteries with my SC DAC , because the DIR9001 maximum working voltage is given as 3.6V.
A freshly charged LiPo will be above that voltage.
I will however, in the next few days be trialling 2 Energiser Ultimate Lithium batteries in series for the DIR 9001, and another 2 for the 3.3V supply to the DAC

A number of things can influence results, for me the main thing I had with the flea is whats posted above. I never found the actual cause and couldn't fix it totally when used with the B32.
I do remember on the original Buffalo I had a problem on one channel after fitting the PH regs, the high's suffered occasional spit, cut a long story short I had damaged one of the Buffalo's SMD ceramic caps which goes across the pins, possibly over heated or slightly fractured after soldering the regs legs across the ceramics ends to try and keep things close as possible to the chip pins. Anyway after replacing the ceramic the problem was no more. Its one reason I wasn't too eager to remove the BII's ceramics even with the batteries

[Deleted]

The reason I mention this is that there is no reason to assume that 1 mOhm Z power source will sound better than a 10 mOhm one, as sandyk seemed to be hinting at earlier.

dangiovanni
I wasn't hinting at that. It is also impractical.
I believe that the impedance should be as low as possible over a wide bandwidth, as well as very low noise.
That is why I fitted a JLH PSU addon to the modified version of the Silicon Chip HA, as well as bypassing the fuses. The values of the emitter resistors, and their power rating, in conjunction with internal current and thermal limiting in the Voltage Regulators then give considerable protection, although not perfect.
My barb to John was mainly based on him ignoring my reservations on using the DIR9001 at higher than the manufactures stated maximum working voltage of 3.6V. John knows my feelings on this subject, but was dismissive of them. He also knows that if the LiPo was 3 or 3.3V I would have checked it out in my SC DAC long ago.
In view of the fact that my conciliatory and friendly PM to John was taken out of context, as shown by my small quote that I posted.
I fail to see why John should once again brought up that absolute maximum voltage in the data sheet of -0.3V to +4V.
I would advise RG members to never exceed the manufacturers stated maximum working voltage, as it often leads to I.C. degradation, at least in the long term , or worse.Exceeding the ratings of the AD8066 by a small amount is a good example of this.

It should also be said that John's postings are often very aggressive, although I do realise it is just his style. This has resulted in his sin binning, or worse, in a few other forums.
John also knows that I have consistently supported him in one of those other forums.
Alex
,

[jkeny]

Alex,
I think you should let readers make up their own minds about the tone of my posting. I don't appreciate being selectively singled out as having commercial interests or being accused of mustering the troops.

BTW, I asked a question (that you might have missed) about declaring conflict of interests here or information that could be considered biasing your view or bona fides (seeing as you brought it up) - neither you nor Leo nor Grottojones have answered this request.

I'll let others decide whether you genuinely could try these LiFePO4 batteries or whether you are rationalising things. BTW, the batteries when fully charged at 3.7V fall to 3.3V within seconds of usage so your worries could be easily overcome (if you were interested)

[Deleted]

Oct 9, 2010 21:29:36 GMT jkeny said:

Alex,
I think you should let readers make up their own minds about the tone of my posting. I don't appreciate being selectively singled out as having commercial interests or being accused of mustering the troops.

BTW, I asked a question (that you might have missed) about declaring conflict of interests here (seeing as you brought it up) - neither you nor Leo nor Grottjones have answered this request.

I'll let others decide whether you genuinely could try these LiFePO4 batteries or whether you are rationalising things. BTW, the batteries when fully charged at 3.7V fall to 3.3V within seconds of usage so your worries could be easily overcome (if you were interested)

John
I did briefly contemplate the fitting of a "crowbar" circuit to heavily load the LiPo for a short period , but this is not really practical. Although the results should be very enlightening, I feel that the added complexity of regular charging of the battery a little daunting as it would mean regularly removing the top cover of the 1U rack case, and recharging the battery(s) with the special charger that is essential to avoid either an explosion or fire . This aspect of LiPos is extremely well documented.
I know of at least one Buffalo DAC owner who will not try the LiPos because of the inconvenience factor.
Do you have information as to how trickle charging during use could be implemented ? Or is that not possible with this kind of cell ?
Alex

P.S.
I am just a DIYer , and have been for around 60 years.
I have no commercial ties of any kind whatsover.
Neither have I ever sold anything that I have constructed.
Members who I have assisted with their problems can attest that I would not even accept payment for replacement components used, or even for sending them a JLH PCB or 2.
My views are my own, based on my own personal experiences, and those of some very qualified authors etc.

[jkeny]

Alex,
At last you ask some questions & it reveals why I've been correcting you.

These are NOT LiPO batteries - they are LiFePO4 - a different formulation. They don't explode or burst into flames! Check them out! The simple battery charger schematic that I offered to send you will charge the batteries to whatever voltage you set & will then turn off. It is a fit & forget i.e no inconvenience factor of any sort!

No need for a crowbar circuit!

Edit: You should check my website for more information! This charger is now contained within the box - no need for external charger.

PS. I had a customer kill their batteries by using a 7.2V charger (two battery charger) for a period of time until the batteries died - no explosion, no fire, no noxious fumes - the endcap just separated & something came out - I could only see the remnants of the spill in the box

[Deleted]

Oct 9, 2010 21:50:58 GMT jkeny said:

Alex,
At last you ask some questions & it reveals why I've been correcting you.

These are NOT LiPO batteries - they are LiFePO4 - a different formulation. They don't explode or burst into flames! Check them out! The simple battery charger schematic that I offered to send you will charge the batteries to whatever voltage you set & will then turn off. It is a fit & forget i.e no inconvenience factor of any sort!

No need for a crowbar circuit!

Edit: You should check my website for more information! This charger is now contained within the box - no need for external charger.

PS. I had a customer kill their batteries by using a 7.2V charger (two battery charger) for a period of time until the batteries died - no explosion, no fire, no noxious fumes - the endcap just separated & something came out - I could only see the remnants of the spill in the box

Are you saying that they can not explode if the correct charger and correct charging procedure are not used ? That is not what my "googling " found when I used the correct designation.
As regards charging, this would imply that there would need to be a charger connection fitted to the DAC,or an auto charging circuitry installed inside the DAC, which is in use when the DAC is switched off, as well as for safety reasons, a means of disconnecting the batteries from the circuit while the batteries were being charged. Again, more inconvenience and additional expense for such a little gain.Especially with my DAC
Perhaps it is worthwhile with things such as the HiFace which uses USB. It would then also appear to be much better to use the same SPDIF capable DAC from a good quality soundcard's SPDIF, or perhaps better still, a Firewire connection if the DAC had one.

[jkeny]

Oct 9, 2010 22:11:53 GMT @sandyk said:

Oct 9, 2010 21:50:58 GMT jkeny said:

Alex,
At last you ask some questions & it reveals why I've been correcting you.

These are NOT LiPO batteries - they are LiFePO4 - a different formulation. They don't explode or burst into flames! Check them out! The simple battery charger schematic that I offered to send you will charge the batteries to whatever voltage you set & will then turn off. It is a fit & forget i.e no inconvenience factor of any sort!

No need for a crowbar circuit!

Edit: You should check my website for more information! This charger is now contained within the box - no need for external charger.

PS. I had a customer kill their batteries by using a 7.2V charger (two battery charger) for a period of time until the batteries died - no explosion, no fire, no noxious fumes - the endcap just separated & something came out - I could only see the remnants of the spill in the box

Are you saying that they can not explode if the correct charger and correct charging procedure are not used ? That is not what my "googling " found when I used the correct designation.

You are googling LiPO & NOT LiFePO4 - I keep telling you this

As regards charging, this would imply that there would need to be a charger connection fitted to the DAC, and for safety reasons, a means of disconnecting the batteries from the circuit while the batteries were being charged. Again, more inconvenience and additional expense for such a little gain.Especially with my DAC

You're making unfounded assumptions again - the charger is smaller than a battery & could be inside the DAC - a switch would allow you to disconnect the battery from the DAC while charging & how do you know it would be "little gain"?

Perhaps it is worthwhile with things such as the HiFace which uses USB. It would then also appear to be much better to use the same SPDIF capable DAC from a good quality soundcard's SPDIF, or perhaps better still, a Firewire connection if the DAC had one.

I don't know what you are saying here?

Please, you need to do some proper research before making all these wrong assumptions based on wrong information!

[leo]

I'll stick with whatever gives ME the best results and continue recommending it, as soon as something comes along which I feel is better I'll post about it. The whole idea of these threads is to post your own findings. If batteries direct work better for somebody else thats fine, I certainly won't go changing my opinion though just because it doesn't match somebody else .
Its nothing to do with being biased

[jkeny]

Oct 9, 2010 22:19:49 GMT leo said:

I'll stick with whatever gives ME the best results and continue recommending it, as soon as something comes along which I feel is better I'll post about it. The whole idea of these threads is to post your own findings. If batteries direct work better for somebody else thats fine, I certainly won't go changing my opinion though just because it doesn't match somebody else .
Its nothing to do with being biased

Yes, Leo I agree with you - let people post their impressions & findings & the readers can decide - that is the only way to proceed with equanimity.

I've been told I have a commercial bias in this & that I mustered some people to come here to disparage your findings - seeing as I was being accused of a bias, I just wanted everybody to put their cards on the table & say what might be considered to influence their opinion in this.

For instance, you have made a big investment in these Paul Hynes regulators already with something like 10 in your existing Buffalo32 & 10? in your other Buffalo. This would represent a big investment of something like 600GBP, I reckon. This would be psychologically difficult to walk away from. Now I'm not distrusting your ears but we hear with our brain & our mood & psychological predisposition can influence what we hear!

[paulhynes]

John,

Actually there is nothing stopping people using a battery power source with my regulators or anyone else’s for that matter, and in fact, a number are doing just this, both personally and commercially, and some have been doing this for a long time. I am open minded enough to support this and I am about to post details of this option on another forum. Some will be happy to use batteries and some will not, for a variety of reasons. My task is just to help people get further if I can, whichever camp they choose. Mains driven power for regulators is just an option as is battery drive. The fact that historically most people using my regs have used mains derived power to feed the regs is irrelevant. The battery driven reg has to be considered as an option to the direct battery drive, and it is very relevant, whether you have seen reference to this application or not, particularly if we are seeking an open debate to discover which is best sounding option for the Buffallo in the AVCC role.

I recently told Leo and a number of others about my Altmann Dac battery experiments so it is hardly surprising that he is trying this out on his Buffalo DAC.

Wow! I wrote the above earlier before the evening entertainment began at home and, just checking before crashing, the thread has moved on somewhat. I’m too tired to go through it all now so I will look at it tomorrow and reply accordingly.

Regards
Paul

[leo]

Oct 9, 2010 22:33:26 GMT jkeny said:

Oct 9, 2010 22:19:49 GMT leo said:

For instance, you have made a big investment in these Paul Hynes regulators already with something like 10 in your existing Buffalo32 & 10? in your other Buffalo. This would represent a big investment of something like 600GBP, I reckon. This would be psychologically difficult to walk away from. Now I'm not distrusting your ears but we hear with our brain & our mood & psychological predisposition can influence what we hear!

You may want to get the facts right before posting something like this John

[jkeny]

Leo, I'm sorry if I got the numbers or £ wrong – your posted pictures here & elsewhere show a lot of PH regs in your various devices - maybe you should declare the numbers & £ for complete transparency?

About measurements & particularly the impedance of the LiFePO4 batteries, I posted a link a few pages ago to a paper by Sandia National Laboratories, CA entitled “Selected Test Results from the LiFeBatt Iron Phosphate Li-ion Battery” which I don’t think anybody looked at based on the posts since.

So let me extract some information:
For the AC impedance test – here’s what they say: “The frequency range shall be large enough to encompass the anticipated network response, and in this case corresponds to a range of 100 kHz to 10^-4 Hz. At least six different frequencies per decade shall be measured.”

And in the results section they say “The high frequency impedance of the cell is essentially the same before and after PSOC pulsed cycling. The small decrease in impedance from 4.01 mΩ to 3.74 mΩ after cycling ……” They are talking about the impedance at 100KHz of 4mΩ here (& the fact that it doesn’t change after repeated charging (PSOC)).

Alex, you might want to look at the section titled “Over Voltage/Charge Abuse Test” where “At about 110 °C the cell vents liquid electrolyte without any fire or sparks and then open-circuits at 116 °C.”

[paulhynes]

Dangiovanni,

As any regulator can be used with either battery or mains derived power feed, it is still my opinion that only testing regulators with mains derived power will give an incomplete picture when comparing the sonic effect of batteries verses regulators. I am sorry if this upsets you but it is my opinion, which I believe is acceptable in an open discussion.

I listen for primarily musical impression but appreciate transparency as well. I have to say that I have heard a number of reputedly transparent systems that have done nothing for me musically. I will take musical enjoyment every time.

I have to admit that the output impedance of a power supply is more relevant with dynamic loads than constant current loads, however I would have to include use with dynamic loads as part of a design specification for any power supply offered to market as the majority of loads fall into this category.

I am not responsible for the opinions of others on this thread.


John,

I did read the Sandia paper you referred to and agree the measurements look impressive which is why I am interested in investigating these batteries as they may be beneficial for a wide variety of applications for audio and also applications that are not audio related. I have in mind energy storage for large scale photovoltaic arrays and wind turbines. There is a big push on at the moment for renewable energy development in the Western Isles. I would like nothing better than to get my house off grid with power costs inexorably rising.

I must note that the battery tested by Sandia was a 10 amp per hour battery and this would be expected to have significantly lower impedance than the A123 battery you recommend. For this reason some performance measurements would still be useful to this discussion for audio applications. I will get around to this when time allows.

Now I am off for a walk on the beach as it’s a beautiful day here.

Regards,
Paul