I have a large number of transformers in my AV system. I know that naim amps are known for a bit of hum, any way to reduce this without altering the performance, damping, shielding mounting ?
You have to distinguish between:-
1. Transformer 'rattle' - arises with loose laminations in E-core transformers
2. 'Growl' arises in toroids when DC is present on the mains
3. Hum - arises when the transformer (E-core or Toroid) radiated field intersects wiring loops internally or externally in an audio system
All three require different solutions. You best make a recording of your problems using your mobile and hen post it up - it should be possible to determine which it is.
🙂
1. Transformer 'rattle' - arises with loose laminations in E-core transformers
2. 'Growl' arises in toroids when DC is present on the mains
3. Hum - arises when the transformer (E-core or Toroid) radiated field intersects wiring loops internally or externally in an audio system
All three require different solutions. You best make a recording of your problems using your mobile and hen post it up - it should be possible to determine which it is.
🙂
It wont cut and past, 'file not recognised' I cant pick it up with attached file - banked out. Alas I don't subscribe to any social media, its a file detailed below
Upload it to a service like wetransfer, and post link. Or use online zip service, zip, and upload zip here.
I know I am up against it as I have 20 transformers 'on' when I play one film disc, 2 are R core the rest are torroid, most 400VA or bigger
Okay, I have to go, so I guess someone else will have to do... I didn't get a reply via email...
JT
JT
A proven solution consists of a rectifierbridge, with a bi-polar capacitor across it. It will stop the slight DC that can exist in power lines, that will tend to saturate transformers.
So every household is different.
These DC-buffers can also be bought ready dor. Use..
So every household is different.
These DC-buffers can also be bought ready dor. Use..
triode_al: You mean like this? I have done this on my Hiraga an it has hardly any hum.
My Dynamic Precision DPA 6.1 was on service for a half year ago, on that can hear hum within 1 meter from amp.
Frank
My Dynamic Precision DPA 6.1 was on service for a half year ago, on that can hear hum within 1 meter from amp.
Frank
I don't recommend doing that blindly. You use snubber, by calculating values (preferably using quasimodo). But that may not be an issue here, we are waiting for audio 🙂
Sagen: like that but more often with a larger bipolar, say 1000 µF, that is two polarized 2.200F in series. It is to allow the AC a low resistance to overcome the 1.2V threshold. The 1µF silver cap you have would look better in its coupling capacity 🙂giggle🙂.
Coincidentally I had a technical problem last night partly caused by transformers. It was a very large US built device with power transformers for the electronics. These were totally encapsulated in a closed steel enclosure that offered no ventilation and functioned as shorted winding as well (unbelievable but true). When the device had a technical issue it shut itself down by software. Switching off power and then switching it one caused the primary fuses to blow immediately as the transformers were very low ohmic because of the still very high core/winding temperature. So it ended up with 2 issues 🙂
, such that on start-up there appears to be a short. Line resistors to the rescue: the thermistor.