DC Blocker

[spkrdctr]

"Either way the power plant shouldn’t be locking up. I assume “lock up” means the control software is crashing and the P20 power has to be cycled to recover?"

That is my take also. You would be surprised how a few new components can fix a troublesome circuit. Most people do not know and engineers do not like to talk about it, but electronic components are a real crap shoot at times. They fail all the time or are defective from the manufacturer. It just isn't high enough of a failure rate to really cause a business serious problems. In today's digital world it is cheaper to just replace an entire circuit board then to troubleshoot to the component. If your P-20 is under warranty,it needs to go to a repair shop. If it is not under warranty, they should send you a new board which will replace almost the entire guts of the P-20 and have you send your old board back for examination. But, I don't run the company!

 

[BDH55]

Sorry, got distracted for almost a week with plumbing problems. First it was the plugged branch line... then our hot water tank left us... and today it was my new friends at Roto-Rooter showing up to clear the kitchen sink drain line and letting me know that our kitchen remodelers 'glued' all the traps etc under the sink!

Anyway, back to my original issue... first, to clarify what I meant by my P20 'locking up'... I'll try to explain exactly how I am using the P20 and what I am seeing. My P20 is the heart of my main rack... everything plugs into it, and it is plugged into a dedicated 20 A line. While the P20 can be used to switch different zones on and off, I leave all my zones powered on so all my equipment has constant power. That said, I do turn the display off when I am not using my system, and back on when my system is on.

So what happens is I will sit down to listen/watch and notice that the display on my P20 is already on. At that point I know thru experience my P20 'controls' are locked up. In this case, 'locked up' means non-responsive to both the remote and/or front panel inputs. The only way to get functionality back is to kill the main power and bring it back up. The good news is I still have power to all my equipment and I 'believe' my P20 is still doing it's job. Since I keep all my zones on, I don't really need my remote, but... thinking about the price point on this piece of equipment, I expect it to work!

The latest is I challenged PS Audio support about recommending I install a DC Blocker to solve the problem, when Paul's video said that they have a DC Blocker inside the product. They went to Engineering, and now the feeling is that I have some spurious IR signals confusing my P20. While this seems odd as I also have a P12 that has never had an issue, the recommendation was to cover the IR receiver with some electrical tape and see what happens. So far, so good, but I also went thru a period of probably 3 months without having my lockup, so I guess we will see...

 

[spkrdctr]

If the tape trick works that will give you an answer. I have issues with my Yamaha receiver turning on at weird times. I know it is some weird signals etc in my apartment complex. It does not happen often, maybe once a month at most. So, if the tape trick works you have your answer. I hope it is fixed.

 

[BDH55]

If the tape trick works that will give you an answer. I have issues with my Yamaha receiver turning on at weird times. I know it is some weird signals etc in my apartment complex. It does not happen often, maybe once a month at most. So, if the tape trick works you have your answer. I hope it is fixed.

Well, so far, so good! That said, while tape may help eliminate any further DC blocker discussion, it doesn't really solve the problem. It's more like a bandaid that hides the problem. Plus, I would really like to be able to use my remote when I need to use it. Of course, me having to climb behind my rack to do a hard power reset isn't a very good solution either as I'm not getting any younger (and am losing my ability to safely work behind it as well).

You mentioned earlier about returning it for service. PS Audio is certainly willing to take a look at it, and I've thought about it. The biggest issue would be recruiting a couple of the neighbors not only to pull it from my rack, but box it, and get it to a shipper (and again on the flip side), as well as being completely shut down. Of course my biggest fear is that since there was a stretch of at least three months where my P20 ran fine, would they even find a problem? Of course now that they are leaning toward this being an IR issue, returning to them looks even less like an option. Certainly appreciate the suggestion however...

 

[BDH55]

Here's the latest on my P20 issue....

I put the electrical tape over the IR sensor on 3/17/21... and it has not locked up once since then. IIRC, the longest period my P20 ran without locking up in the past was maybe three months. Soooo, it sure is looking like some spurious IR signal seems to selectively target my P20,

Is there any reasonable way to identify where these signals are coming from and potentially eliminate them? I would like to get my P20 remote working again... besides, my P20 looks better without the tape across the front of it!

 

[spkrdctr]

I found out what was turning on my Yamaha AVR every once in awhile. It was my computer! It was using Bluetooth to tell the Yamaha to turn on and be ready for music. I found it by accident. Turned off my computer Bluetooth and problem is solved. Trying to find the signal problem for you will be tough. I just can't believe that they sell that P20 for so much money with no real method of fixing them. Who would pay the cost to ship it to PS Audio after they injure themselves getting it ready to ship? It is crazy. For the price PS Audio should pay for shipping and all under warranty. If it is off warranty then of course they would say to junk it and buy a new one. I have no real answer for your problem. It is not often I'm stumped but in very expensive audio it happens. I'm stumped on how to get them to fix their product.

 

[Phil in Ocala]

Much of this technology is driving me nuts...Apple is the worst....it does not permit you to see the password you are entering on the iphone...as if we all work for the CIA...in fact...Tim Cook now wants you to have TWO passwords...next year THREE.....

 

[spkrdctr]

Much of this technology is driving me nuts...Apple is the worst....it does not permit you to see the password you are entering on the iphone...as if we all work for the CIA...in fact...Tim Cook now wants you to have TWO passwords...next year THREE.....

Yup, the idiots are running the world now. It gets so stupid. If you need 3 passwords on your phone, then something is wrong with the design/engineering of the phone. Plus, if you do not put any important info on your phone then you do not have to worry about it. It's crazy. There are people still running around by the millions everyday that think they have privacy on their phones! Most people are clueless about the fact that EVERYTHING on their phone is an open book. The cameras and microphone can be turned on at any time WITHOUT your phone showing it as being turned on. The only guaranteed privacy is to take out the battery of the phone. I guess Ed Snowden didn't teach anyone anything......

 

[BDH55]

I found out what was turning on my Yamaha AVR every once in awhile. It was my computer! It was using Bluetooth to tell the Yamaha to turn on and be ready for music. I found it by accident. Turned off my computer Bluetooth and problem is solved. Trying to find the signal problem for you will be tough. I just can't believe that they sell that P20 for so much money with no real method of fixing them. Who would pay the cost to ship it to PS Audio after they injure themselves getting it ready to ship? It is crazy. For the price PS Audio should pay for shipping and all under warranty. If it is off warranty then of course they would say to junk it and buy a new one. I have no real answer for your problem. It is not often I'm stumped but in very expensive audio it happens. I'm stumped on how to get them to fix their product.

I'm not really sure that I would put this one on PS Audio. After all, they did spend time trying to help me get to the bottom of this, and assuming it truly is some spurious IR signal in our home, I'm not sure I can hang that on them as that seems outside their control. Although, it would be nice if the P20 was designed to just ignore these signals, but I am not an engineer so no idea if that is even possible. Also, I still find it odd that I also have a P12 located less than seven or eight feet from the P20 and the P12 has never had an issue (although, the P12 is tucked in behind my Illusion center).

Regarding the warranty... it is still under warranty but I would still have to pay the freight to get it out to them. Even if they paid the freight, it would take my main system completely down until they got it back to me. However my bigger concern would be that they would return it with 'no trouble found' and once I reinstall it in my environment, the problem would reappear...

 

[Brad225]

Have you tried bringing all of the IR remotes your have in the house and trying to see if any button on them with re-create the problem.
Should you be lucky enough to find one that does, I guess your take it back to where ever you normal would use it and see if some strange IR signal can somehow go around corners to find the P20.

 

[Stefan_DR3]

Although, it would be nice if the P20 was designed to just ignore these signals, but I am not an engineer so no idea if that is even possible.

Absolutely. If the software has the ability to parse through valid IR codes it should be able to just drop any unrecognized IR codes without hanging the system. However the fact that they have built in logging software and the talent to connect remotely and examine the logs suggests they have the tools and data needed to debug the crash. I still think it's encountering a strange waveform or transient on the AC side and the software locks up trying to handle it. Usually when engineers are stumped they put in more code to log more details next time it happens or happens to other customers. If it is a spurious IR signal they will want to find out why their code locks up because of it and fix that!

 

[spkrdctr]

All in in all, it is a tough problem. The question might be, can you move the P20 to somewhere close to the P12 just to see if it stops when moved.by the P12. It is a lot of back breaking lifting but it might fix the problem. Your system will be down for awhile but it might be worth it. If moving it to a semi-secluded spot like you P12 fixes it, then you could plan your wiring etc. for a permanent move to fix it. That is all I can think of. I'd rather have it work correctly with the remote than worry about positioning etc. But then I live in a one bedroom apartment with an ML system that no woman would ever approve of. My wife just grins and bears it....ok, not so much the grinning part!

 

[BDH55]

Have you tried bringing all of the IR remotes your have in the house and trying to see if any button on them with re-create the problem.
Should you be lucky enough to find one that does, I guess your take it back to where ever you normal would use it and see if some strange IR signal can somehow go around corners to find the P20.

No, haven't tried that but that would be relatively easy to try. I did uncover an old Pioneer LD player remote when cleaning up some stuff, so for one thing, I can just clear out some stuff that I no longer use which I suppose could make a difference as well...

Absolutely. If the software has the ability to parse through valid IR codes it should be able to just drop any unrecognized IR codes without hanging the system. However the fact that they have built in logging software and the talent to connect remotely and examine the logs suggests they have the tools and data needed to debug the crash. I still think it's encountering a strange waveform or transient on the AC side and the software locks up trying to handle it. Usually when engineers are stumped they put in more code to log more details next time it happens or happens to other customers. If it is a spurious IR signal they will want to find out why their code locks up because of it and fix that!

Okay, good to know. As for the AC side of things... remember, their initial thoughts were all about it being a large DC spike coming in, and they were tracking those. That had me looking for solutions to stop DC spikes when someone posted a PS Audio video with Paul McGown talking about their regenerators having a DC blocker already built in! It was when I pushed that back to PS Audio support that they reversed course by telling me it might be a spurious IR signal, and how they wanted me to test. Every day that goes by with the IR receiver covered and no lockups, seems to make it more likely that it is an IR issue...

All in in all, it is a tough problem. The question might be, can you move the P20 to somewhere close to the P12 just to see if it stops when moved.by the P12. It is a lot of back breaking lifting but it might fix the problem. Your system will be down for awhile but it might be worth it. If moving it to a semi-secluded spot like you P12 fixes it, then you could plan your wiring etc. for a permanent move to fix it. That is all I can think of. I'd rather have it work correctly with the remote than worry about positioning etc. But then I live in a one bedroom apartment with an ML system that no woman would ever approve of. My wife just grins and bears it....ok, not so much the grinning part!

I suppose I 'could' swap my P12 and P20. Of course I couldn't run part of my main system with the smaller P12, but actually that still would give me some good info. Unfortunately, not only would that be a ton of work, but the bigger problem is while the P12 would fit where my P20 is currently located... the P20 will not fit where the P12 is located. I could jury rig a temporary solution just using a couple of power strips to power all those devices, but it seems like if I was going to go thru this much work I would want to know a) if the P12 locks up when located where the P20 normally sits, and b) if the P20 continues to lock up when moved to where my P12 normally sits.

This is a good suggestion that I will certainly keep in mind, but part of my hesitance is I recently unloaded most of my rack to clean and re-arrange some things (everything came out except the P20 and power amps). I also spent a bunch of time labeling and tying down cables and doing some general cable housekeeping. While I would mostly be unplugging a bunch of cables from the back of my P20, I'm not sure I want to take the chance of screwing something else up. Also, it just isn't a very comfortable space for me to work in and if I would get stuck, I don't really want to find out how fast the fire department can disassemble my system using the jaws of life to rescue me!!!

I do appreciate everyones suggestions!

 

[Stefan_DR3]

Okay, good to know. As for the AC side of things... remember, their initial thoughts were all about it being a large DC spike coming in, and they were tracking those. That had me looking for solutions to stop DC spikes when someone posted a PS Audio video with Paul McGown talking about their regenerators having a DC blocker already built in! It was when I pushed that back to PS Audio support that they reversed course by telling me it might be a spurious IR signal, and how they wanted me to test. Every day that goes by with the IR receiver covered and no lockups, seems to make it more likely that it is an IR issue...

I don’t think a DC blocker would block a transient spike anyway, because they are designed to block DC offset. When they say “DC spike” I am not sure but picture a brief transient like a lopsided AC waveform that only lasts a half cycle or less. Strange that PS Audio would change course, as presumably there was an AC input power event logged that led them to this prognosis, not an IR event. Perhaps they have lost sight of facts or should revisit your logs.

 

[BDH55]

Perhaps they have lost sight of facts or should revisit your logs.

That's certainly possible, especially since they've been dealing with this off and on for almost two years and the original people working on it kind of lost interest (my opinion). I had just gone thru a particularly bad stretch of three lockups inside one week when Scott McGown sent out a mass email about them restarting their PowerPlay interface (web interface that graphs out THD, Temp, Voltage and Wattage on their PowerPlants)... so as someone with a sizable investment in their PowerPlants (P3, P12 and P20) I responded about PowerPlay, but also let him know I wasn't very happy with my P20. Amazing how a comment to the owner's son gets lots of resources rallying around the issue! Of course it has once again gone quiet as my P20 seems to work just fine as long as I have the IR receiver covered... maybe it is time to give Scott an update...

 

[spkrdctr]

I would think by now 2 YEARS!! they would have said to send it in. They could have easily replaced it for you with a new one and then put in a new board (all electronics) in your old one and sold it as a refurbished unit and still make a ton of money again as refurbished. They would make money twice on the same unit! I think they are being lazy but that is just my opinion. Plus, I like PS Audio but as Biden would say, "Come on Man!"

 

[BDH55]

I would think by now 2 YEARS!! they would have said to send it in. They could have easily replaced it for you with a new one and then put in a new board (all electronics) in your old one and sold it as a refurbished unit and still make a ton of money again as refurbished. They would make money twice on the same unit! I think they are being lazy but that is just my opinion. Plus, I like PS Audio but as Biden would say, "Come on Man!"

Just to clarify... they have offered to take a look at it. It's been me that's pushing them to find a remote solution. Not only would it be a huge pain in the ass to pull out and ship back to them, but I am really afraid that since this is an intermittent problem it could end up coming back to me with 'no fault found' (especially if it is from either the AC spike or spurious IR signals). That said, I am keeping an eye on my warranty end date to make sure that I don't miss it if I do need to ship it back to them.

Also, they are aware that this has cost them some business because I'm concerned about their QC. Through our discussions they were aware that I was thinking about new amps, and they really wanted to send me a pair of their BHK 300 mono blocks to demo. However I told them I wasn't interested simply because I now own five pieces of their gear, and four out of the five have had issues (two requiring return for repair). They have been helpful and responsive in resolving issues and I am happy with all my PS Audio products... well, except for my P20...

 

[barjohn]

I'm not sure where all of this talk of DC being on the power lines comes from. In the early days of electricity DC was the power generated but they could only deliver it short distances because DC loses voltage as the distance from the source increases or requires larger and larger conductors to increase the distance. It wasn't until they changed to AC (alternating current) that long transmission lines became possible. They are a low frequency (60Hz) and the impedance needs to be matched to reduce transmission losses. Additionally since power = volts x amps, they had to go to high voltage to reduce the diameter of the lines used as for the same power the amps decrease as the voltage increases. To my knowledge, there is no practical way for them to put DC on their power lines, nor any reason to do so. Those big transformers are oil filled for cooling. Any sound you hear is likely to be do to the corona discharge from the high voltage lines feeding the transformer. Put a DC meter across your AC power line. If any DC is present you will read it. If it read 0v then you don't have DC present.

Transient spikes are a possibility but you can easily filter these out with either an power strip with lightening protection or using a battery backup power unit which will filter out any transients.

 

[JonFo]

One other source of spurious IR can be fluorescent lights and LED lights. Did you recently change a bulb in the area to an LED?
Note: can be outside the room in a hall even.

I hate IR as a 'remote control' as A) it is unidirectional (no feedback or status queries) and B) is a line-of-sight (unless deploying repeaters) thing.
Bluetooth and IP are the ideal methods.

 

[Tosh]

Mains DC and Transformers

ESP - The Audio Pages. Even a small amount of DC offset on the mains is enough to cause problems. Find out how it happens and how to fix the problem.

sound-au.com

"There are any number of different machines that can create a mains supply DC offset. Most will be totally outside your control, many DC 'events' will be transient in nature, but one common theme applies - they will all load the mains supply asymmetrically for a period of time that ranges from a couple of cycles to minutes at a time."