I would start with a simple and cheap trick that has worked for me a few times. I also tested it instrumentally with a spectrum analyzer.
Put a snap-on ferrite on the power supply cable of the preamplifier. This is the one that worked at best for me: https://www.we-online.com/catalog/datasheet/74271222.pdf. This is the captive (cheaper) version with the same measured efficency on my application: https://www.we-online.com/catalog/datasheet/742700790.pdf
There are many equivalent products from other suppliers. I had this one on hand when needed, and it worked.You may also put the ferrite on signal cables, but on my case the issue was on the power cable. This snap-on ferrite is on stock on most electronic distributors.
Grazie PCAN. I will have my friend in Torino try this as well. I am currently looking into a Phoenix-Victron Inverter and battery solution, but I would rather solve the issue in a simpler way. I think your problem was emission-related that triggered noise on the supply. Conversely, his problem is conductive, in fact when he uses a UPS and goes to battery mode, the problem disappears completely.
Note, I had him use the double MIT Z-chord filtered cable to power the units with no difference. Let me look into having him also try the ferrite as a test. Thanks for your input.
Note, I had him use the double MIT Z-chord filtered cable to power the units with no difference. Let me look into having him also try the ferrite as a test. Thanks for your input.
Naresh,
Thank you. I understand the isolation transformer might not be a good idea, so I scratch that off. Also, I tried the MOV (without filter) but it had no effect on the problem.
To capitalize on the degree of the issue he is experiencing with his electrical system, even a UPS system which I assume has filters and surge protection, yet it merely improves but does not completely resolve this disturbance.
I will have my friend measure the E-N AC voltage when the system is working and drawing full power.
His system draws 1200W, the preamp is about 100W while the power amp about 1100W therefore it is a challenge to power it with batteries should an inverter and battery be used.
You mentioned line conditioner, what is the difference between a line conditioner such as this https://www.tsipower.com/product/344 and a dedicated inverter like this https://www.victronenergy.com/inverters/phoenix-inverter-12v-24v-48v-800va-3kva ?
Both solutions above are very expensive and the problem is that I don't know which will produce better sound and most of all, which will degrade less from the sound produced by the main line.
TSI has their Asia Pacific plant near my factory, I can vouch for them.
The Victron, no idea, to be honest.
TSI uses IGBT drive (no relay or triac), and has very good isolation, fast (15 ms) response time, and output is controlled to +/- 1 Volt in the nodels sold here.
They gave one more or less by force to a major car maker for their welding robots, next week they wanted 50 ASAP, their robots were having line noise problems...
The Victron, no idea, to be honest.
TSI uses IGBT drive (no relay or triac), and has very good isolation, fast (15 ms) response time, and output is controlled to +/- 1 Volt in the nodels sold here.
They gave one more or less by force to a major car maker for their welding robots, next week they wanted 50 ASAP, their robots were having line noise problems...
thanks for your feedback. TSI looks like a great unit and based on what you say, I have no doubt it can resolve the line issue. While both TSI and VICTRON can both highly solve the issue, in an audio system you also deal with which solution produces a better sound quality. I will discuss with my friend which solution he prefers to try, given that both are extremely expensive tries.
about Power Conditioners
In that 'power conditioner' is an undefined term. It could mean almost any combination of the following.
a) Noise filter - a low-pass EMI/RFI filter.
b) Surge protector - although it's better to have surge protection at the home's service entrance.
c) UPS - note that many UPS's are not really UPS's!
d) Line voltage adjuster.
e) Balanced power transformer.
f) Isolated power transformer.
g) DC blockers.
h) Regenerators (PSAudio)
i) Power Factor Correction
j) Sola Constant Voltage Transformers, also called Ferroresonant power conditioners
k) I forget? But I think that there are more.
In that 'power conditioner' is an undefined term. It could mean almost any combination of the following.
a) Noise filter - a low-pass EMI/RFI filter.
b) Surge protector - although it's better to have surge protection at the home's service entrance.
c) UPS - note that many UPS's are not really UPS's!
d) Line voltage adjuster.
e) Balanced power transformer.
f) Isolated power transformer.
g) DC blockers.
h) Regenerators (PSAudio)
i) Power Factor Correction
j) Sola Constant Voltage Transformers, also called Ferroresonant power conditioners
k) I forget? But I think that there are more.
You are correct, the power conditioners contain many of those features and they all help keeping the line clean. However, when it comes to sound and we are all here for this, at the end of the day, many of these technical solutions might affect the actual performance.
My friend just told me, in the past he tried a brand power conditioner, and it did indeed make the sound flatter and in the end worse. I am sure not every power conditioner will behave the same, but in the end, we opted for inverter and battery.
My friend just told me, in the past he tried a brand power conditioner, and it did indeed make the sound flatter and in the end worse. I am sure not every power conditioner will behave the same, but in the end, we opted for inverter and battery.
TSI units are voltage regulators, with line noise filters, input is AC only to my knowledge.
UPS implies a battery backup and inverter, to be used when there is a line failure.
TSI were using Fairchild transistors and other top quality components when I last visited their factory, product is world class.
Other voltage regulators used transformer tappings, and relays or triacs to switch the output voltage as desired, TSI uses IGBT to actually modulate the output, and response is very fast.
They use a choke or similar as a filter, so line noise removal is good.
But I must emphasise that the result will be the user's experience, and I have no ties to TSI, and others involved in that business.
UPS implies a battery backup and inverter, to be used when there is a line failure.
TSI were using Fairchild transistors and other top quality components when I last visited their factory, product is world class.
Other voltage regulators used transformer tappings, and relays or triacs to switch the output voltage as desired, TSI uses IGBT to actually modulate the output, and response is very fast.
They use a choke or similar as a filter, so line noise removal is good.
But I must emphasise that the result will be the user's experience, and I have no ties to TSI, and others involved in that business.
I am aware you have no financial interest into TSI and you are recommending it based on your experience. In fact, I had my friend looking into this product in Italy to have a distributor demo it for him, but unfortunately, no sales in Italy that is why I have him looking into the inverter and batteries.
This solution poses another set of issue for him which is space which he has not. I wished there was an easy solution to his electrical system so there was no need to add these expensive and bulky devices.
This solution poses another set of issue for him which is space which he has not. I wished there was an easy solution to his electrical system so there was no need to add these expensive and bulky devices.
Has your friend tried using a different electrical outlet? Maybe temporarily with an extension cord if it's far from the system. Also try rotating the plug in the socket so as to swap live with neutral (Italian sockets are not polarized). If the preamplifier is not new, the power supply may have one of the Y filter capacitors open due to wear.
First, like I said, get a qualified and experienced electrician to check the wiring from the meter to all the outlets.
Could be something as stupid as water heater plug got heated, and is arcing, which then sends electrical noise everywhere.
TSI and other devices are a very much last stage option, for want of a better expression, I am sure a simple solution exists.
Could be something as stupid as water heater plug got heated, and is arcing, which then sends electrical noise everywhere.
TSI and other devices are a very much last stage option, for want of a better expression, I am sure a simple solution exists.
I am going to have him try different outlets in the house. I am not clear how his electric system is configured in his house, but if I understand correctly, he has 3 dedicated lines to the meter which go to the audio room. He will try few different configurations and I post what changes.
The preamp is new.
I am trying to have him call the electrician to check carefully his electric system. I will also tell him to have the electrician check for heater plugs and other items.
Strangely, when he stiches on and of the washer just turns it on and off without having it operating, it causes the problem which leaves me startled.
I do agree the power conditioning and inverter is the last line of defense.
Check the washer, change the motor capacitor on it, and connect 275V/20mm MOV Line to Neutral permanently in its power outlet.
And a proper arc suppressor, or use 0.1 uF/400V and a 1K 2W resistor in series as arc suppressor. Use suppressor in parallel with MOV.
And a proper arc suppressor, or use 0.1 uF/400V and a 1K 2W resistor in series as arc suppressor. Use suppressor in parallel with MOV.