Like others I hear from here, my brand new edcor xformer has a very loud buzz .. I have been around enough similar transformers over the years to know its not what a high quality/functioning xformer should sound like. Talking with edcor did not leave me feeling sending it back was worth the hassle or cost. . Has anyone had any luck sending back buzzing edcor xformers? Anyone make high quality xformers that are reliably quiet? I am not super price sensitive though good value would be appreciated...
This is a source of real frustration. I just built a pair of monoblocks for a friend, sent them across the country, and he can hear a slight mechanical hum from the Hammond 270-series power trannies. We confirmed it's not DC offset in his AC line. He's sending them back and I'm going to try some Hammond 370-series. I've also ordered some custom power trannies from Heyboer which are about the same price as the 370-series. I'll report back but I don't have anything definitive to offer yet.
Have you confirmed it's not DC offset in your own line?
unless you are not overloading your transformers, it should not buzz...
let us say you are not, so it is a mechanical thing, so what you can do is dismantle the end bells, and wedge popsicle sticks in between the cores and the bobbins if they have not done already..
still dipping into a vat of air drying polyurethane plastic varnish several time will surely help..
lastly, tightening the bolts and nuts on the transformer itself can be all that is needed, good luck..
let us say you are not, so it is a mechanical thing, so what you can do is dismantle the end bells, and wedge popsicle sticks in between the cores and the bobbins if they have not done already..
still dipping into a vat of air drying polyurethane plastic varnish several time will surely help..
lastly, tightening the bolts and nuts on the transformer itself can be all that is needed, good luck..
good questions - to test the xformer, the primary is being fed direct from 120V 60HZ power (really 117v) the xformer is unloaded i.e. secondaries are unconnected. I have tried tightening core bolts and angle changes and pushed on the core and the bobbin in interesting ways to see if the sound changed. If did not - using a screwdriver as a 'stethoscope' it appears to be coming from the core - not the bobbin - hard to be sure though . It was packaged really well by edcor and appeared to have zero shipping blemishes i.e. no visible hits/drops etc.
I am trying to spec transformers for a project that might lead to many being used so having to fiddle with them a lot is problematic. This really comes down to a vendor quality/support issue. I would rather spend a bit more for the best and best supported. Its not really fair but I have used a fair number of Hammond with any complaints before but its zero for one with edcor
I am trying to spec transformers for a project that might lead to many being used so having to fiddle with them a lot is problematic. This really comes down to a vendor quality/support issue. I would rather spend a bit more for the best and best supported. Its not really fair but I have used a fair number of Hammond with any complaints before but its zero for one with edcor
The Hammond 270 series is well known to have mechanical buzz. People who switch to the more expensive 370 series always report good news, they are much quieter.
i design and build my own transformers, although i have not seen the 270 and 370 series, what i can tell is that the 270 is closer to saturation than the 370, that is the only reason i can think of....my transformers are designed and built more farther away from saturation, well below the knee of the saturation curves so that i never had problems that many of you may be having...
FWIW, closer to saturation is how you get more power and better regulation, but the tradeoff is it can really buzz. if your primary line voltage gets higher than it should...
Yes, me too. ;-) I will report on the Heyboers, won't have them for a few weeks. But I know they've built replacements for other people and I have heard no complaints...
The Edcor mains transformers in a pair of monoblocks I built a few years ago hummed. The chassis tops acted like sounding boards.
I reduced the level of the humming to tolerable levels using these:
Fabreeka Anti Vibration Mount Flex Loc Q4 or these
Fabreeka Anti Vibration Mount Flex Loc Q5
I reduced the level of the humming to tolerable levels using these:
Fabreeka Anti Vibration Mount Flex Loc Q4 or these
Fabreeka Anti Vibration Mount Flex Loc Q5
Mine were already isolated on a Delrin subchassis. Unfortunately my friend has a very small room and very acute hearing, and they definitely "sing." OTOH, I have a Hammond 270-series tranny sitting on a preamp breadboard right now and there is no issue. But the current load is considerably smaller.
My pair of Edcor PTs hum a little. Not enough to really bother but when right between them, as when I change a record, you are aware of a slight hum. From a couple of feet there is nothing intrusive - certainly not enough for me to tear back into the mono-blocks.
Customer service basically told me tough luck. Next time I will try Monolith Magnetics. I received my output transformers about 10 days from my order and they are in Belgium whereas Edcor is way closer.
Customer service basically told me tough luck. Next time I will try Monolith Magnetics. I received my output transformers about 10 days from my order and they are in Belgium whereas Edcor is way closer.
true 95% of the time for line preamps, because you cannot make the power transformer any smaller than you would like to have it..
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The trouble is whether the buzz comes from the speakers or the transformer its going to affect your musical experience. If you think its to do with loading you could always disconnect the HT and heater and just try mains only. No transformer manufacturer wants bad press including here - I think you have grounds for return as not fit for purpose.
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