Strange intermittent hum noise since Kismet amps in system (video attached)

0 Members and 1 Guest are viewing this topic. Read 1483 times.

dpatters

I know everyone is suggesting regenerator. I would consider UberBuss

Don P

Early B.

I know everyone is suggesting regenerator. I would consider UberBuss

Yeah, it's easy to suggest that someone drop $5K on a PS Audio P15 and all of their problems will magically disappear, but there are less pricey (and free!) solutions to the inevitable transformer hum.

klaus@odyssey

Forgot:

did you try to plug the amps directly into the wall....????

Rusty Jefferson

  • Full Member
  • Posts: 560
Yeah, it's easy to suggest that someone drop $5K on a PS Audio P15 and all of their problems will magically disappear, but there are less pricey (and free!) solutions to the inevitable transformer hum.
My apologies, but it seems a reasonable suggestion for both members struggling with the same issue.  What the OP showed in his video is unacceptable for any system.  I think everyone understands it's the power grid and not necessarily the equipment.  Could you outline the free and inexpensive solutions to transformer buzzing? 

I see the UberBuss website is down currently so no information there about whether it will stop transformer buzz. It appears to be a filter/conditioner which may (or may not) be able to stop the buzzing.  Perhaps someone who had this particular problem and fixed it with the UberBuss will chime in.

Lkdog

Hey guys-

Thanks for all of the suggestions. Learning a lot here.


Klaus
- I did plug them straight into the wall. Have not been around much today so have not been here to listen. Its been quiet so far.
Are basic surge protectors like Tripplite Isobar considered bad or degrading in a system??
This is what I have. I have all of my stuff plugged into a couple of these. Not good idea??  What do people normally use?   :scratch:





As for investing a lot into some type of line filter, or power regenerator- not sure. Not opposed to something priced fairly reasonable if it does not degrade the sound and it works. Certainly do not wish to spend more than I have in the Kismets, though. Klaus was kind enough to bias them to match my voltage which varied from 120.8 to 121.1. They have been great. This hum is annoying, but pretty random and not debilitating. Of course would like it gone and if some type of power line filter/regenerator unit will improve all of my components further will consider that.

My system is pretty nice, but modest and maybe not considered super high end.
OPPO 105 source/VAC signature LE preamp/ Pioneer Elite SC-71 HT/ ACI Jaguar monitors/ACI LFM dual subs/ and the Kismet Amps.

One question I have about a power regenerator or higher end filter of some type is how powerful does it need to be considering the Kismets are beasts??





genjamon

If he has DC riding on his AC, then I don’t think the Uberbuss will solve it.

I had suggested PI Audio not for the Uberbuss, but for his other product that provides surge protection (can’t remember the name). But I would only suggest that solution if his amps sounded fine with no hum when plugged directly into the wall.

I’m not sure OP needs power conditioning if he’s happy with the sound and if the Tripp Lites are the source of the problem. In that case, it’s just a matter of removing the Tripp Lites and replacing with a more transparent and noise-free approach to surge protection (if desired). If surge protection is not necessary, then an economical but high quality power strip without conditioning or surge protection would probably suit him well. He doesn’t seem to be looking to invest in comprehensive power conditioning at this time.

jmolsberg

This is what I replaced my tripp lite with.

https://www.cullencable.com/111-2/

I do plug a tubed dac and tubed phono pre into this with excellent results

https://audience-av.com/conditioners/ar2p/

firedog

This sounds like you have DC offset on the line.
You can check for it without special equipment.

Basically, it means unplugging EVERYTHING in the house and throwing all the breakers to off. Then you turn each breaker on one by one to see if the hum occurs. If not you plug in EACH device one by one to see if hum occurs. You plug in the appiances on the same circuit as your amp and the rest of the system last. In this way you can isolate the source of the hum. There are descriptions exactly how to do this elsewhere on the forum.

But sometimes it is coming from a neighbor, etc.

If you get the transformer hum in this test, then apparently it's DC on the line.

Some of the boxes suggested to you won't deal with DC offset. They fix AC.

I suggest you go to the Van Alstine site and look at their "humbuster" it is an inexpensive box that's specifically  for getting rid of DC on the line. It works. Worked for me. No need to spend multiple 3 figures or 4 figures.

Lkdog

OK. UPDATE.

The hum did occur briefly in early morning for a short time with amps plugged directly into the wall.
I did listen to a fair amount of music with them plugged into wall. Didn't notice any real difference in sound.

Anyway, let's assume there is DC offset somewhere in the universe that is getting into the line.
My head is kind of spinning right now. Want to make sure I am looking at right units.
The above poster suggests a solution from Van Alstine I will check out. (thanks).
What others specifically will also address that?
The PS Audio units I assume. The Ifi Power station?
« Last Edit: 18 Oct 2020, 04:43 pm by Lkdog »

genjamon

I second the hum buster suggestion. There’s also a DIY DC blocker circuit I remember being mentioned here before. If you were into DIY, you could probably assemble it and basically make a Humbuster-like device yourself. These are likely your cheapest options to deal with DC if you can’t discover and eliminate the source of the DC.

Another alternative is to buy an isolation transformer unit, and plug your amps into that.  Transformers block DC by their very nature. In fact, that is a key purpose of having them in your amps at all, to make sure only AC passes into the power supply circuits of the amp. But if you go the route of buying an isolation transformer unit, then you run the risk of the isolation transformer humming instead of your amps, depending on how sensitive it is to DC.  I actually suspect I have DC in my line. I tried a relatively inexpensive non-audiophile type isolation transformer before, and it hummed like a beast. Unusable. Then I bought an Equi=Core brand balanced power transformer, and it only has a very light hum you can only hear when up close to the unit. Good enough for me. My whole system is plugged into it.

A balanced power transformer also has power conditioning benefits. By its very nature, it rejects a significant amount of noise on the AC. The Equi=Core product is the most affordable BPT I have seen on the market, and is only about half the cost of the PS Audio P5/P12 mentioned above. But significantly more expensive than the Humbuster approach.

And again, none of these will provide surge protection.

TomS

The AVA humbuster products or DIY are a very good recommendation. If you also need better surge suppression try the ZeroSurge products. Relatively inexpensive and they don't use noisy MOV's, very effective industrial quality devices. We're in SW Florida, where power is always iffy, lots of lightning in the area during summer, so I use them on everything electronic. So far, so good.

Rusty Jefferson

  • Full Member
  • Posts: 560
...Another alternative is to buy an isolation transformer unit, and plug your amps into that.  Transformers block DC by their very nature...
Exactly. That big ass transformer on the telephone pole outside your house is blocking DC. If your neighbor was intentionally putting DC on the AC of his house, it's not getting to your house. It's unlikely transformers buzz because of DC coming into your home, and it's also unlikely you're generating DC inside your home unless you've got some really old tube radio equipment turned on. It's also difficult to measure to see if there's DC on the AC line but it can be done and the most likely scenario is there will be none.

The buzzing is most likely caused by noise on the AC line perhaps because of poor or corroded connections at the pole or at the meter, or just because of location, distance from the substation, etc.  Whatever the issue, something at the point of use seems like the best answer.  If the Humbuster or UberBuss do it, great. I've never seen someone post saying they had this particular problem (transformer buzzing) and cured it with one of those devices.   :D

abd1

  • Jr. Member
  • Posts: 246
    • DailyFrenchie
I had some hum with a tube amp and tried an Van Alstine humbuster. It didn't help. I like Frank's products, have the SET120 amp, but my hum issue wasn't what the humbuster fixed. The only product I've tried that has removed hum or buzz is the PS Audio P5 regenerator.

Tyson

It might be a grounding mismatch between components.  In which case only something like the P5 will fix it.  Or, the other option is to use some Jensen Audio line level iso transformers between your dac/preamp/amp.  I've tried both and the P5 is a better solution.

klaus@odyssey

Try the obvious first before going down the rabbit hole (where, admittedly, you can get lucky)

Put them straight into the wall for a few days first !!!!!!!!!!!!!  The amps are well protected,  unless, of course you're in the middle of this one...




Lkdog

Try the obvious first before going down the rabbit hole (where, admittedly, you can get lucky)

Put them straight into the wall for a few days first !!!!!!!!!!!!!  The amps are well protected,  unless, of course you're in the middle of this one...





Well, since it is a misty cold day here in Iowa I have been in my basement listening room most of morning.
Amps have been plugged straight into the wall outlets.

The transformer hum is pretty loud a couple times already this morning.  :o :cry:

So short answer is that isn't clearing it up. Might have been better plugged into the Tripplite Isobars FWIW but it is so random hard to say.

Bottom Line is I need something to tame the DC on the line.




Lkdog

Maybe this would help?

https://avahifi.com/collections/accessories/products/humdinger-dc-line-blocker

Yep. Looking at that. Some say it is great. A couple people here don't think so, but always a lot of opinions in the audio world. LOL.

Doublej

  • Full Member
  • Posts: 2324
I know everyone is suggesting regenerator. I would consider UberBuss

Don P

I am not suggesting a regenerator. I am suggesting figuring out what is causing the problem and then addressing it directly. But to audiophiles that's no fun. Why would an audiophile spend money having a dedicated circuit put in when then can buy a new gadget and then swap it out for something different and purportedly better in a few years?

Sh!t. I just convinced myself I am not an audiophile.