Eva said:
Eva, change the glasses.
It was not random components.
I have calculated those values (for the output of the LM317/337 regs, AFTER the bypass cap) and recommended Rudi to try them on his implementation of my AD815 preamp.
This is on the posts you quoted, but you still insist.
Lost case...
Eva said:
Well I trust that Carlos calculated his recommendation. We could doubt his ability to do the calculation if we want. but as it turned out. it does make a very worth while improvement. I do not throw random components at my equipment. There are several people that have build the preamp exactly according to my spec and they do not have problems.
The problem that i am experiencing has shown itself in the past. Several of my neighbours have similar problems with equipment. In my case it became a bit more obvious. Somebody of the vinyl brigade will have much more pops and clicks to contend with.
I might hear some of these artefacts maybe one or two a minute and then it will be silent for up to a hour.
If I refer to other equipment then i refer to friends of mine that do not live in the vicinity.....
As far as imagination is concerned. I have no doubt that you have been richly blessed with it.
rudi said:
Hi rudi,
As you have just confirmed my earlier guesses that unfortunately you have a massive 'aerial array' continually transmitting HV pulses surrounding you, what I earlier suggested is quite possible or likely to be the cause of this *increased* problem.
In adding the snubber (and I regret I don't presently know precisely where this has been added), and as this has improved the sound as you suggest, it is more than likely that you have simply improved the transient response of your amp. This would have a profound effect on any signals with a very fast rise-time like you have here.
If the snubber is associated with the PS, and you have as a result improved the HF performance of this PS, this is precisely the kind of result I would expect here, especially as you now make it clear that this not a new phenomenon, but that it has become more prominent since adding the snubber.
I had similar experiences some years ago when I improved the transient response of a power amp, whereafter clicks and pops on vinyl records became much more noticeable, much to my dismay. This could be clearly seen by using a digital storage 'scope, and it had nothing to do with any oscillation.
I would guess that you have some part of your set-up which is simply rather sensitive to 'picking up' these regular noises, unfortunately, and now, due to the faster and better particularly HF response of the amp, it has become more objectionable.
Equipment with poorer HF responses and less good resolution can mask these effects, and this is a potential downside to any well-performing gear. It reproduces the 'wanted' sounds rather better and more prominently, so you enjoy greater resolution and details in the reproduced sound etc., but it will also do just the same with any 'unwanted' effects, regrettably.
If this is the case, the best way to identify where this unwanted noise is entering the system is by substitution, if this is possible.
It may not necessarily be in the amp you have added the snubber to, either. It could be in some preceeding equipment, or the interconnects etc., and it is just as likely to be distributed directly to your equipment via the mains cables which also power the electric fence. Simply improving the amp has just has made this more noticeable now.
If you wish to discuss this in more detail, I will be pleased to suggest some ways of 'homing in' on this problem. A handful of members have thanked me for my help in similar situations in the past few weeks on this Forum alone, and I promise I will not bring any "magic chronometers" nor " sixth dimensions" nor will I expect any 'Sir Gallahads' to help me by referring to any "UFOs", in attempting to help with this annoying problem you have.
Regards,
Bobken said:
thank very much Bob
Like Nordic stated we are experiencing a problem with the power grid at the moment and several people that I know complained that there systems ain't as good as they used to be.
I have added the snubber just after the Lm317 Lm337. and as you stated it did improve the transients. removing does mask the problem but is still accurs.
I had the same problems on my DAC a few months ago but never found the cause.
Bobken said:
...and reduced the high output inductance of the regs (which is why they have a steep rising impedance towards the high frequencies, starting very soon in the middle of the audioband), which results in a lower impedance of your PSU, up to high frequencies.
Yes Bob, you are on the right path.
What are the sonic consequences of using a low(er) impedance PSU? I would tell, but they don't wanna know.
You already pointed one out.
Reason for the series resistor
The small value resitor is used as the damper in this application. Its purpose to to prevent or at least reduce ringing in the two paralleled caps.
I doubt that it lowers the impedance of the bypass. But is sholud prevent the ringing. And using a lower quality high impedance cap should do the same thing. Maybe not as well.
I read through Charles graphs early in this thread. Do not remember if leaving the resistor out messed up the impedance or not. If it does actually lower the measured impedance of the cap I have to admit there is magic going on here. Along these lines:
My first tube amp rebuild was a pair of Heathkit W7M's, in the late 80's. I was lost, maybe still am, and bypassed all the caps in the power supply with 0.01 ufd generic polystyrene caps. It sounded like bees. Those cheap caps were ocillating like mad.
Removed them and it cleaned up. Then put even cheaper mylar caps in and the sound got better, and no bees. Learned a easy lession, the polystyrene caps are great someplaces, across the main filter caps of a voltage doubler they were terrible.
If I had known, adding a 0.47 ohm resistor in series should have gotten rid of the bees. The amp most likely would have sound better than it did with the mylar bypasses too.
I am using them in my amp and preamp. Thinking about building another board for my linestage power supply and trying the snubbers there also.
Guess we could be disagreeing about quantum purifiers, 10,000.00 interconnects, and magic pebbles. At least are cheap to try out and listen to the results.
George
The small value resitor is used as the damper in this application. Its purpose to to prevent or at least reduce ringing in the two paralleled caps.
I doubt that it lowers the impedance of the bypass. But is sholud prevent the ringing. And using a lower quality high impedance cap should do the same thing. Maybe not as well.
I read through Charles graphs early in this thread. Do not remember if leaving the resistor out messed up the impedance or not. If it does actually lower the measured impedance of the cap I have to admit there is magic going on here. Along these lines:
My first tube amp rebuild was a pair of Heathkit W7M's, in the late 80's. I was lost, maybe still am, and bypassed all the caps in the power supply with 0.01 ufd generic polystyrene caps. It sounded like bees. Those cheap caps were ocillating like mad.
Removed them and it cleaned up. Then put even cheaper mylar caps in and the sound got better, and no bees. Learned a easy lession, the polystyrene caps are great someplaces, across the main filter caps of a voltage doubler they were terrible.
If I had known, adding a 0.47 ohm resistor in series should have gotten rid of the bees. The amp most likely would have sound better than it did with the mylar bypasses too.
I am using them in my amp and preamp. Thinking about building another board for my linestage power supply and trying the snubbers there also.
Guess we could be disagreeing about quantum purifiers, 10,000.00 interconnects, and magic pebbles. At least are cheap to try out and listen to the results.
George
Talking about research. Have you guys researched this? Have you actually tried it? In a preamp after the regulators or on a amp as suggested by Carlos
Now given there is less of a difference on a amp than on a preamp. But the difference is there and it generally manifests itself as a much deeper tighter bass and more liquid tops.
Now given there is less of a difference on a amp than on a preamp. But the difference is there and it generally manifests itself as a much deeper tighter bass and more liquid tops.
Hi,
I've researched it enough to understand how and why it works.
It then simply becomes another trick in the toolbox, there's nothing mystical about it at all. You'd really think you'd want to research it _first_ instead of "just trying it" and then having to ask "but why, how?" like someone stunned by their first magic trick.
Once you do understand it you can implement it properly if needed. Would it be audible if done right? Still depends on the rest of your system I think.
Would the types of caps/resistors used affect sonics further? No doubt, as they all have their own unique physical properties.
Incidently, I would think compensating for parasitic inductance and lowering impedance at high frequency are one and the same.
I never implied it wouldn't work, I simply implied the odds of it working if you dont' understand it and therefore can't implement it properly are unlikely.
BTW I understand people often use cheap/high ESR electrolytics for the same purpose, and as stated in the other thread a number of different values could be used to achieve the best outcome.
All this information is on the forum at least ten times over..... dig.
BTW imagination is a good precursor to research and experimentation, and it'd be nice if the forum discussions were accompanied by both more often.
Maybe if people answered basic questions with a straight answer for a change such a simple thing wouldn't be turned into such a big ordeal, it only leads one to believe they don't fully understand it themselves, though I believe you do understand it Carlos, so you must enjoy these "debates" a good deal.
I'd also think the sonic consequences would be the same as any other that helps to provide a flat frequency response across the audio band .... and beyond.
Cheers
'Sir Gallahads'
PS: Good luck with the Fence, check the basics like a decent ground.
I've researched it enough to understand how and why it works.
It then simply becomes another trick in the toolbox, there's nothing mystical about it at all. You'd really think you'd want to research it _first_ instead of "just trying it" and then having to ask "but why, how?" like someone stunned by their first magic trick.
Once you do understand it you can implement it properly if needed. Would it be audible if done right? Still depends on the rest of your system I think.
Would the types of caps/resistors used affect sonics further? No doubt, as they all have their own unique physical properties.
Incidently, I would think compensating for parasitic inductance and lowering impedance at high frequency are one and the same.
I never implied it wouldn't work, I simply implied the odds of it working if you dont' understand it and therefore can't implement it properly are unlikely.
BTW I understand people often use cheap/high ESR electrolytics for the same purpose, and as stated in the other thread a number of different values could be used to achieve the best outcome.
All this information is on the forum at least ten times over..... dig.
BTW imagination is a good precursor to research and experimentation, and it'd be nice if the forum discussions were accompanied by both more often.
Maybe if people answered basic questions with a straight answer for a change such a simple thing wouldn't be turned into such a big ordeal, it only leads one to believe they don't fully understand it themselves, though I believe you do understand it Carlos, so you must enjoy these "debates" a good deal.
I'd also think the sonic consequences would be the same as any other that helps to provide a flat frequency response across the audio band .... and beyond.
Cheers
'Sir Gallahads'
PS: Good luck with the Fence, check the basics like a decent ground.
Thanks very much for your feedback
I do agree with everything you have said here and I appreciate it. One has to understand that there is allot of newbies on the forum and allot of them have no electronic knowledge and i have to count myself into that category. i do however have friends and family that do have the knowledge that can help out
Sometimes we do get excited and it is unfortunate that people put a damper on that. WHY? well they will have to ask themselves that.
All the basics have been covered. Good star ground on the PCB at the signal input. Good quality components, nothing over the top. Bypasses as normally recommended. ????? but still i have the occasional pop and click and also the interference from the gate but that i see on my TV as well at times. but we are experiencing very high levels of dirty mains and power outages. One more thing that i will try that did make a difference in the past is to remove the EMI filter. in the pass i had problems with fluorescent lights interfering with it, and by removing it the problem went away
btw. try the AD815 on your class D amps.
I had them on my tripath ta2135 and it really gave it some life.
I do agree with everything you have said here and I appreciate it. One has to understand that there is allot of newbies on the forum and allot of them have no electronic knowledge and i have to count myself into that category. i do however have friends and family that do have the knowledge that can help out
Sometimes we do get excited and it is unfortunate that people put a damper on that. WHY? well they will have to ask themselves that.
All the basics have been covered. Good star ground on the PCB at the signal input. Good quality components, nothing over the top. Bypasses as normally recommended. ????? but still i have the occasional pop and click and also the interference from the gate but that i see on my TV as well at times. but we are experiencing very high levels of dirty mains and power outages. One more thing that i will try that did make a difference in the past is to remove the EMI filter. in the pass i had problems with fluorescent lights interfering with it, and by removing it the problem went away
btw. try the AD815 on your class D amps.
I had them on my tripath ta2135 and it really gave it some life.
I've suffered some horrible clicks/crackles/buzzing, as well. In my case it was the intolerance of the soundcard to have a less than ideal earth ground... possibly high impedance, let to it having alot of noise on it.
The EMI filter could easily be the problem. Certain types can easily help polute the earth ground, so removing that would be good to try. Other basics include twisted wires/cables, shielding... I meant to say shielding where/as required not bypassing, sorry.
I'd think it likely it's ground polution you're hearing, and I wish you luck in getting it sorted.
Just had a quick look at the AD815's datasheet. Very impressive, thanks for the tip.
The EMI filter could easily be the problem. Certain types can easily help polute the earth ground, so removing that would be good to try. Other basics include twisted wires/cables, shielding... I meant to say shielding where/as required not bypassing, sorry.
I'd think it likely it's ground polution you're hearing, and I wish you luck in getting it sorted.
Just had a quick look at the AD815's datasheet. Very impressive, thanks for the tip.
Hi rudi,
Having thought about your 'interference' problem some more overnight, I would like to assist with its possible resolution.
I spite of the earlier rather puerile attempt at pouring scorn on my comments relating to Faraday Cages, I have had some quite relevant experience here. In about 1975, I spent many weeks working in Faraday Cages at the Joseph Lucas Interference Laboratory in the UK, developing commercial solutions to the problems which beset all glass-fibre bodied vehicles, which, of course, have no inherent ability to 'shield' from such unwanted intrusions, unlike steel-bodied vehicles.
Whilst there, I did learn (a little bit!) about the subject of airborne intrusions, and seeing your (and Nordic's) recent comments, I am now less inclined to think that your 'pickup' here is airborne, in spite of the unfortunate immediate 'aerial array' surrounding you. In my experience, when the radiated signal is as 'local' as yours must be here, it doesn't generally *vary* much in its unwanted effects, unlike when the 'transmitter' is many miles away, and where atmospheric changes can then have a marked influence on this annoyance.
Whilst I am still of the opinion that improving the transient response of the amp is what has *most likely* caused this *increase* in interference, I am now leaning towards this being directly transmitted through your mains wiring system. Accordingly, and before struggling with any other more obscure areas, I would like to see this possibility eliminated first, if possible.
You suggest that at some times the problem is less troublesome (if I understand correctly) but with still using exactly the same set-up, which suggests to me that some outside 'influence' is varying here. Also, you suggest that your amp doesn't exhibit this problem when used in other systems, again if I understand correctly, and that your mains quality is very suspect at times.
Some while ago, I finally cured a very similar most aggravating problem for someone else which turned out to be none other than a simple increase in the mains impedance. It was just a loose screw in a mains socket outlet, and once this was found and tightened, the problem disappeared completely. Before this, the poor owner was going mad as every time he switched *anything* in his house, it made terrible noises through his system. As your local mains appears to be 'below par' on many occasions, it could well be a similar problem which is troubling you here, although the integrity of the supply in your case is probably compromised more by the poor distribution from your Supplier rather than it being due to any poor contacts in your own set-up.
This view is reinforced now you also say that other equipment of yours has, at times, shown similar tendencies.
Do you by chance have (or could borrow) an 'inverter' which is adequate to temporarily power your chip amp from a vehicle battery? These are sometimes used by campers etc, to enable them to use mains-powered devices from their vehicles, when away from home. If so, using this would most likely indicate whether it is a direct power-line induced problem, and you could begin with the amp, and try other parts of your system too.
At this stage, curing the problem entirely is not the goal, as any such interference could be being introduced via several paths at once. All you need to do here, is to see if you can 'influence' the problem in some way (even if it worsened, it might indicate something, but I think this is very unlikely!) in a repeatable and positive manner.
Incidentally, this use of a 12v DC to say 220v AC (I don't know what your local voltage is) inverter would be better for this trial, than trying to somehow power the amp from batteries alone, which would inadvertently eliminate parts of the circuitry (like mains cord, transformer, diodes, smoothing caps etc.) which could be a part of this problem.
Failing availability of a suitable inverter, I would recommend you using some TransZorbs between the live & neutral power lines, to see if this will 'slug' the problem. These devices are extremely effective and will cope with voltages of many tens of thousands, and have a very fast response to 'spikes' on the mains. Their clamping action is effectively "instantaneous" and they have no adverse effect on the sound which I can detect, so they can be used as a long-term cure as well. MOVs are not so good here, they are less effective and much slower in operation and I don't like what they do to the sound, either, but if you have access to Farnell's catalogue, I think you should find something suitable there.
I can help you if required with your choice of TransZorb device, which needs to be bi-polar, of course, with a 'reverse stand-off voltage' chosen to suit your local supply. Also, if you cannot get these readily in your part of the world, I will happily send you a couple FOC, if you give me your AC supply details and your address.
These are so small, that you could screw a couple inside a mains plug-top (across live and neutral) and then use this as a 'testing tool' here, on a temporary basis.
The hardest (and most frustrating) part about trouble-shooting any such intermittent problem, is encouraging the problem to manifest itself at your own chosen time, and otherwise you can waste many days, fruitlessly. However, you appear to have some luck on your side here, as you suggest that opening your gates will also cause the problem to show.
This is very useful, as you can then perhaps get an assistant to operate the gates a couple of times to ensure the 'pops' are audible (and roughly assess their amplitude) and then plug the TransZorb 'tool' into a socket as close to your audio equipment as possible, and see if there is any apparent change here.
Use the same approach, of course, if you are able to use an inverter, and see if there is any reliable difference in the intrusive sounds.
Apart from a little patience, this approach will cost you next to nothing, and could at least indicate (as I now suspect knowing some more details of your symptoms) if 'direct pickup' via the mains wiring is the cause of this annoyance, or not.
If you can establish this, one way or another, I will willingly assist with some further suggestions as to how the matter might be further 'diagnosed', and/or even (hopefully!) cured.
I do hope this helps, and apologies to others as this is rather off topic.
Regards,
Having thought about your 'interference' problem some more overnight, I would like to assist with its possible resolution.
I spite of the earlier rather puerile attempt at pouring scorn on my comments relating to Faraday Cages, I have had some quite relevant experience here. In about 1975, I spent many weeks working in Faraday Cages at the Joseph Lucas Interference Laboratory in the UK, developing commercial solutions to the problems which beset all glass-fibre bodied vehicles, which, of course, have no inherent ability to 'shield' from such unwanted intrusions, unlike steel-bodied vehicles.
Whilst there, I did learn (a little bit!) about the subject of airborne intrusions, and seeing your (and Nordic's) recent comments, I am now less inclined to think that your 'pickup' here is airborne, in spite of the unfortunate immediate 'aerial array' surrounding you. In my experience, when the radiated signal is as 'local' as yours must be here, it doesn't generally *vary* much in its unwanted effects, unlike when the 'transmitter' is many miles away, and where atmospheric changes can then have a marked influence on this annoyance.
Whilst I am still of the opinion that improving the transient response of the amp is what has *most likely* caused this *increase* in interference, I am now leaning towards this being directly transmitted through your mains wiring system. Accordingly, and before struggling with any other more obscure areas, I would like to see this possibility eliminated first, if possible.
You suggest that at some times the problem is less troublesome (if I understand correctly) but with still using exactly the same set-up, which suggests to me that some outside 'influence' is varying here. Also, you suggest that your amp doesn't exhibit this problem when used in other systems, again if I understand correctly, and that your mains quality is very suspect at times.
Some while ago, I finally cured a very similar most aggravating problem for someone else which turned out to be none other than a simple increase in the mains impedance. It was just a loose screw in a mains socket outlet, and once this was found and tightened, the problem disappeared completely. Before this, the poor owner was going mad as every time he switched *anything* in his house, it made terrible noises through his system. As your local mains appears to be 'below par' on many occasions, it could well be a similar problem which is troubling you here, although the integrity of the supply in your case is probably compromised more by the poor distribution from your Supplier rather than it being due to any poor contacts in your own set-up.
This view is reinforced now you also say that other equipment of yours has, at times, shown similar tendencies.
Do you by chance have (or could borrow) an 'inverter' which is adequate to temporarily power your chip amp from a vehicle battery? These are sometimes used by campers etc, to enable them to use mains-powered devices from their vehicles, when away from home. If so, using this would most likely indicate whether it is a direct power-line induced problem, and you could begin with the amp, and try other parts of your system too.
At this stage, curing the problem entirely is not the goal, as any such interference could be being introduced via several paths at once. All you need to do here, is to see if you can 'influence' the problem in some way (even if it worsened, it might indicate something, but I think this is very unlikely!) in a repeatable and positive manner.
Incidentally, this use of a 12v DC to say 220v AC (I don't know what your local voltage is) inverter would be better for this trial, than trying to somehow power the amp from batteries alone, which would inadvertently eliminate parts of the circuitry (like mains cord, transformer, diodes, smoothing caps etc.) which could be a part of this problem.
Failing availability of a suitable inverter, I would recommend you using some TransZorbs between the live & neutral power lines, to see if this will 'slug' the problem. These devices are extremely effective and will cope with voltages of many tens of thousands, and have a very fast response to 'spikes' on the mains. Their clamping action is effectively "instantaneous" and they have no adverse effect on the sound which I can detect, so they can be used as a long-term cure as well. MOVs are not so good here, they are less effective and much slower in operation and I don't like what they do to the sound, either, but if you have access to Farnell's catalogue, I think you should find something suitable there.
I can help you if required with your choice of TransZorb device, which needs to be bi-polar, of course, with a 'reverse stand-off voltage' chosen to suit your local supply. Also, if you cannot get these readily in your part of the world, I will happily send you a couple FOC, if you give me your AC supply details and your address.
These are so small, that you could screw a couple inside a mains plug-top (across live and neutral) and then use this as a 'testing tool' here, on a temporary basis.
The hardest (and most frustrating) part about trouble-shooting any such intermittent problem, is encouraging the problem to manifest itself at your own chosen time, and otherwise you can waste many days, fruitlessly. However, you appear to have some luck on your side here, as you suggest that opening your gates will also cause the problem to show.
This is very useful, as you can then perhaps get an assistant to operate the gates a couple of times to ensure the 'pops' are audible (and roughly assess their amplitude) and then plug the TransZorb 'tool' into a socket as close to your audio equipment as possible, and see if there is any apparent change here.
Use the same approach, of course, if you are able to use an inverter, and see if there is any reliable difference in the intrusive sounds.
Apart from a little patience, this approach will cost you next to nothing, and could at least indicate (as I now suspect knowing some more details of your symptoms) if 'direct pickup' via the mains wiring is the cause of this annoyance, or not.
If you can establish this, one way or another, I will willingly assist with some further suggestions as to how the matter might be further 'diagnosed', and/or even (hopefully!) cured.
I do hope this helps, and apologies to others as this is rather off topic.
Regards,
Bobken said:
I do hope this helps, and apologies to others as this is rather off topic.
Regards,
Hi Bob
That is really very nice of you. I gladly accept. (Can you drop me a mail then we can take it offline)
I will check with some of friends if they have something in the line of a inverter. i am sure i will be able to dig one up somewhere. I will check for the FOC here. I am sure I can get something like that here. I will check with the Farnell distributor
I still have to check the EMI filter. I have serious doubts about it in the system. as far as i can recall it was the problem in my DAC as well.
But mains borne it most certainly are. It is almost as if it spikes back into the system.
Maybe I should also ask my dad to help as well. he is a retired electrical engineer with a very keep interest for what i get up to, specially the snubbers
he also says that he can't see how it can work but the music proved differently- Status
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