Help! Torus Isolation Transformer Buzz Sound

[dallasjustice]

I have used a Torus RM 60 in my system for about four years. About a year ago, I noticed a hum sound coming from the Torus. It wasn't that bad since I couldn't hear it from seat position about 20' away. However, the hum is now a loud buzz sound which is easily audible at seated position.

I reported the problem to Torus about a year ago and they wanted a recording of it. I didn't have time to do that. So they didn't offer any solutions. Maybe this video is enough evidence to diagnose the problem?

Any advice is helpful. Thanks.

 

[DonH56]

Can you send the video to them? Sounds like a classic case of transformer buzz to me. Essentially some of the energy through the transformer is translated to mechanical energy. If you've ever put your hand on one you can feel it vibrating (humming). The transformer mounts may need to be tightened, or perhaps the mounting buffers (if present) have dried out, or the transformer itself could be buzzing (various reasons for that, none really user-repairable).

 

[dallasjustice]

Thanks. I've sent it to the dealer. Maybe he can help me out.

Can you send the video to them? Sounds like a classic case of transformer buzz to me. Essentially some of the energy through the transformer is translated to mechanical energy. If you've ever put your hand on one you can feel it vibrating (humming). The transformer mounts may need to be tightened, or perhaps the mounting buffers (if present) have dried out, or the transformer itself could be buzzing (various reasons for that, none really user-repairable).

 

[Thomas savage]

Both my belles monoblocks and indeed the tx in my preamp power supply( one of those that's inclosed in a plastic housing) buzz a little but they always have. Most likely a issue going from 60hz to 50hz mains I guess.

How loud is your buzz?

Is there some new 'dirty ' appliance In your crib?

My old isolation tx in the loft would make that sound now and then too but not constantly.

 

[dallasjustice]

Ever since Stereophile went 420, I added grow lights to my listening room. I just wanted to have the same experience. You think that could be it?

Both my belles monoblocks and indeed the tx in my preamp power supply( one of those that's inclosed in a plastic housing) buzz a little but they always have. Most likely a issue going from 60hz to 50hz mains I guess.

How loud is your buzz?

Is there some new 'dirty ' appliance In your crib?

My old isolation tx in the loft would make that sound now and then too but not constantly.

 

[Thomas savage]

Ever since Stereophile went 420, I added grow lights to my listening room. I just wanted to have the same experience. You think that could be it?

Well if smokin real fine grass don't sort it out , it's a damn serious issue man..

I read of folks putting a tight metal band round their tx to stop mechanical buzz, the type you screw tight...?

Is that bonkers and totally inadvisable , obviously I'm making this thread all about me and my problems now ( must have high oestrogen levels today)

 

[Ken Newton]

I have used a Torus RM 60 in my system for about four years. About a year ago, I noticed a hum sound coming from the Torus. It wasn't that bad since I couldn't hear it from seat position about 20' away. However, the hum is now a loud buzz sound which is easily audible at seated position.

I reported the problem to Torus about a year ago and they wanted a recording of it. I didn't have time to do that. So they didn't offer any solutions. Maybe this video is enough evidence to diagnose the problem?

Any advice is helpful. Thanks.

A typical cause for transformer hum/buzzing is D.C. present on the power mains feed. It may seem odd that the power mains could have D.C., but the reason typically has to due with reactive loads (electric motors, etc.) sharing your mains feed circuit. That usually results in the problem appearing sporadically. I presume from your product's name that it utilizs a toroidal transformer. Toroids are notorious for being susceptible to hum caused by D.C. on the mains. The reason has to due with their tight magnetic coupling, which makes their core saturate very quickly in the presence of D.C. current.

There is a diy solution for curing mains D.C. based hum which utilizes large capacitors and some power diodes, and which is easily found via Google, but it is not what I would describe as an elegant solution. The easiest and least costly solution may be to simply move the conditioning unit in to an adjacent room if one is available. That wouldn't cure the hum, and may requre longer power cords (hmm, perhaps, it wouldn't be the least costly )but then you wouldn't have to listen to it hum. The isolation transformer in your conditioner prevents any mains D.C. being sent to components plugged into the conditioner.

 

[dallasjustice]

Thanks. That's very interesting. I have noticed that the buzz sound comes and goes to some extent. It's always present but it's much louder at certain times. However, once the buzz gets loud, it stays very loud unless I shut off the torus for a while and restart it.

One common cause of transformer hum/buzzing is D.C. present on the power mains feed. It may seem odd that the power mains could have D.C., but the reason typically has to due with reactive loads (electric motors, etc.) sharing your mains feed circuit, which can make the problem appear sporadically. I presume from your product's name that it utilizs a toroidal transformer. Toroids are notorious for being susceptible to hum caused by D.C. on the mains. The reason has to due with their tight magnetic coupling, which makes their core saturate very quickly in the presence of D.C. current.

There is a diy solution for curing mains D.C. based hum which utilizes large capacitors and diodes, and which is easily found via Google, but it is not what I would describe as an elegant solution. The easiest and lowest cost solution may be to simply move the comditioning unit in to an adjacent room if available. That wouldn't cure the hum, but at least you wouldn't have to hear to it. The isolation transformer in the conditioner does prevent any mains D.C. being sent to the components plugged into that conditioner.

 

[dallasjustice]

Here's a picture of my panel. The torus is hooked up to 2 30amp 220v circuits. I can't move it to another room.

 

[cjf]

Interesting...my Torus RM20 has just recently started making the same noise. Its only a year old. It seems to be load related in my case. When I hooked up my two Pass Labs Amps to it is when I noticed it. The buzz is barley audible with only one Amp powered up but when I power up the second is when the noise gets louder.

Mine is only audible from 2-3 feet away so far but I fear it will probably end up in the same state as yours at some point. Shipping one of these beasts back to the manufacturer is not something I look forward to, and mine is small compared to your yours.

 

[Thomas savage]

tx buzz is not weird but the fact there's been no buzz for so long then it started out the blue is weird..I'm guessing it's exterior factors still though and not faulty transformer.

 

[Ken Newton]

Guys, if you can access some second isolation transformer unit somewhere (it can be cheap, sound quality doesn't matter for the following test), you can easily verify whether the hum is being caused by D.C. on the mains, or instead that your unit is defective. Simply plug the second isolation transformer into the wall, and the humming Torus unit into the second isolation transformer, thereby cascading them. The second unit's isoltion transformer will prevent transmission of any mains D.C. to the cascaded Torus unit. The second isolation unit may (or may not) hum itself, but if the Torus unit stop humming, you likely have D.C. on your power mains, and, so, the Torus unit may not be defective.

 

[DonH56]

https://emotiva.com/products/accessories/cmx-2

 

[dallasjustice]

i doubt I'll be able to do this. I also wonder whether the torus' quiet operation for a few years on the same circuit indicates the real problem isn't the unit. Also the torus uses this to power up.

Guys, if you can access some second isolation transformer unit somewhere (it can be cheap, sound quality doesn't matter for the following test), you can easily verify whether the hum is being caused by D.C. on the mains, or instead that your unit is defective. Simply plug the second isolation transformer into the wall, and the humming Torus unit into the second isolation transformer, thereby cascading them. The second unit's isoltion transformer will prevent transmission of any mains D.C. to the cascaded Torus unit. The second isolation unit may (or may not) hum itself, but if the Torus unit stop humming, you likely have D.C. on your power mains, and, so, the Torus unit may not be defective.

 

[Ken Newton]

https://emotiva.com/products/accessories/cmx-2

Don, that looks like a nice and relatively inexpensive solution. I might consider getting one for my own power amp, which utilizes a toroid and occasionally buzzes.

Dallas, on the other hand, appears to be operating his own power company sub-station, what with his having two 30A, 220V circuits powering his A/V system! Oh, well, we audiophiles.

 

[Thomas savage]

Don, that looks like a nice and relatively inexpensive solution. I might consider getting one for my own power amp, which utilizes a toroid and occasionally buzzes.

Dallas, on the other hand, appears to be operating his own power company sub-station, what with his having two 30A, 220V circuits powering his A/V system! Oh, well, we audiophiles.

He's from Texas, going big is the law there.. go big or move to California..

 

[RayDunzl]

My left monoblock transformer would hum (more like a groaning sound) intermittently with some unknown utility power defect.

I discovered and complained about intermittent low voltage that I found while investigating (summer).

The Power Company engineer hung a recorder off my meter outside, and a month later a crew showed up and replaced the transformer on the street two houses away.

About the same time I bought the Equitech (similar to the Torus but 15 Amp version - is that Torus running balanced outputs?), so, unsure now which change fixed my trouble. Probably the utility transformer changeout.

Talking to the guy in charge of that little job, he said the transformers originally installed in a subdivision often became too small as folks add loads over the years. My usage has increased a bit, too. Read from right to left:

Dallas, on the other hand, appears to be operating his own power company sub-station, what with his having two 30A, 220V circuits powering his A/V system! Oh, well, we audiophiles.

I've got all my gear plugged into one shared 15A outlet with probably a 70 foot run of romex 12awg to the breaker box, that includes loads from the outlet with all the PC stuff across the room, and the kitchen overhead lights.

I can pop the breaker listening loudly with the the kitchen overheads on and a 750W vacuum cleaner running. It's never opened for mere musical and computing tasks.

 

[DonH56]

Don, that looks like a nice and relatively inexpensive solution. I might consider getting one for my own power amp, which utilizes a toroid and occasionally buzzes.

Dallas, on the other hand, appears to be operating his own power company sub-station, what with his having two 30A, 220V circuits powering his A/V system! Oh, well, we audiophiles.

Thanks Ken. I am embarrassed I didn't think of DC but I have only seen that a few times. Sometimes it is caused by stuff within the house, too.

Dallas, you might want to contact your power company, as they can also test as they did for @RayDunzl. One datum that will be good to get first is whether or not it still buzzes at the dealer's place. If so, it might indeed be a problem with the unit and not your house.

 

[amirm]

Often times the noise is amplified by the case. Just kick it, flex it, bang on it and see if makes it less loud. No, that's not a joke!

 

[Speedskater]

Most DC problems on the AC power main in a residential neighborhood, will be time, day and season dependent. Very few HVAC or big appliance units run 24 by 7 summer and winter.
In fact it's not DC current, it's harmonic distortion causing a DC offset. Audio editing programs can check for this on an audio file.
Rather than a DC problem, it may be a high AC line voltage problem. With US line voltage drifting towards 125V a transformer expecting 115/117/118V might not be happy.