^^^
Just like I've been saying, you get abberated signal and possibly more noise floor. Also we're talking about lots of SE equipment. I know half the people in here think Pin1 still applies, but the other half know that in countless amplifier designs Pin1 means buzz and awful anoise at the speaker so you need to isolate the jacks full-well knowing you're opening up to some parasitics... which can come from AC line, too.
They're extremely tight. The wire is much more solid and stiff than it looks. But I probably will some day buy some kind of crimp machine that isn't going to destroy my forearms.
My problem with these statements is that most the time it's true, but then the rest of the time people have old man hearing and what is fatigue/undefined to me is "dynamic" to them. You have to recall that a lot of rooms and placement of gear is tuned with the enoise, so when it's gone things may need a few changes. There's also voicing in some gear that purposely tries to correct the results of poor AC quality... that never helps. Then you have people like Lamm who use moronic filters that are only compatible with their equipment and mixing can cause awful results, and even worse they totally F-up the whole situation with power conditioners.
FWIW I think this is the kind of system Richard is talking about:
FELICIA - A DIY Balanced Power Conditioner
FELICIA - A DIY Balanced Power Conditioner
Typical of people to go to familiar safe territory when obvious issues are in front of you.
Looking at an amp and talking about line conditioning is a great case in point. Those amps do not exist in isolation. The network of connections between the boxes is the bigger issue and line conditioning will change the leakage currents but not eliminate them. Even 1000 dB psrr won't remove currents flowing across chassis.
Looking at an amp and talking about line conditioning is a great case in point. Those amps do not exist in isolation. The network of connections between the boxes is the bigger issue and line conditioning will change the leakage currents but not eliminate them. Even 1000 dB psrr won't remove currents flowing across chassis.
There's been pictures that go about making scary looking impulses plenty. That's all well and good, but tells no one anything about, at the end of the day whether that shows up on the speaker terminals, where the rubber meets the road.
Is that what you're showing? Is this across the DC rail, or vdrop across the diode during conduction? (That would seem too low for the latter though, even on some of the lower vdrop schottkys)
PSRR is proportional to loop gain, to a large degree, so of course it falls off with frequency. Was that ever a question?
Demian--your question is why I asked about from end-to-end when everything is connected behind the same isolation transformer. Not either/or with actually managing the floating potentials/differential signaling.
I did, in my NAD mid-fi amplifier. Some mV of RF junk on the supply rails, absolutely nothing at the output, except some 500uV of 50Hz and 150Hz mains harmonics.
I think I’m ******, what should I do?
I will be in The Orient … quaint word … S.E.Asia (Bangkok) on Tuesday.
The company which built them for Monster still sells power conditioner products. I will give you feed back about them if any one wants to buy instead of DIY. I need to check and measure them. I have the network analyzer there to do it with. I shipped the same unit to them and it is in my office there. The engineering has been done for you and the build.
All the units from Monster were UL/VDE/CE approved. They have many features in them... sequential off-on-off, significant surge and spike protection and CATV cable protection etal. And line voltage meter +++
I dont make money on anything from them. I am there now for other reasons…. to help them organizationally and to do audio amplifiers. There were Monster branded/distributed audio power amps that were extremely well performing and bullet proof. They were all CFA and MOSFET OP.
Those came in stereo and multi-channel for surround. Great amps at great prices on eBay.
THx-RNMarsh
The company which built them for Monster still sells power conditioner products. I will give you feed back about them if any one wants to buy instead of DIY. I need to check and measure them. I have the network analyzer there to do it with. I shipped the same unit to them and it is in my office there. The engineering has been done for you and the build.
All the units from Monster were UL/VDE/CE approved. They have many features in them... sequential off-on-off, significant surge and spike protection and CATV cable protection etal. And line voltage meter +++
I dont make money on anything from them. I am there now for other reasons…. to help them organizationally and to do audio amplifiers. There were Monster branded/distributed audio power amps that were extremely well performing and bullet proof. They were all CFA and MOSFET OP.
Those came in stereo and multi-channel for surround. Great amps at great prices on eBay.
THx-RNMarsh
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Nice.
Now, do some real science....
Measure the total current flowing through one of your IC's. Clamp over the entire cable.
If it's a perfect system (which it isn't), you will find that the lower audio frequencies can be picked up by clamping over the IC.
And if your really good, you will find the same thing happening with your line cords. You will see lf audio content on the power cords if you clamp over all three conductors.. LF current that should be returning to the preamp via the IC, but doesn't. It takes the lower impedance path to return to the preamp.
jn
Nice.
Now, do some real science....
Measure the total current flowing through one of your IC's. Clamp over the entire cable.
If it's a perfect system (which it isn't), you will find that the lower audio frequencies can be picked up by clamping over the IC.
And if your really good, you will find the same thing happening with your line cords. You will see lf audio content on the power cords if you clamp over all three conductors.. LF current that should be returning to the preamp via the IC, but doesn't. It takes the lower impedance path to return to the preamp.
jn
Been there. Done that. With power cords, too. I still have all equipment to it again.
One of the probes I will get is very tiny and it can used to localize the noise to a single pin or pcb trace.
Don't worry. I have several HP and TEK clamp-on type probes. Tek AM503, TEK P6042. HP and Fluke 43b also. Outputs can also be sent to a spectrum analyzer.
THx-RNMarsh
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I have some old PA supply transformers (big) with lots of taps they should work here (step up/down are same ratio). Still looking for the $20 BOM.
Ed, I recommend you never try to get a job designing generators or motors.
That statement indicates "gaps" in magnetic design knowledge. People who design resolvers kinda know better.
Jn
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