Mind bending rumble trouble

[Whaleudder]

A phono cartridge can act like an antenna. The steel frame might be sympathetically reflecting EMI into your cartridge.

I think you should join a HAM radio forum and post this issue, those guys understand antennae. The fix might be a simple as coiling one or more wires around a ferrite inductor core or even shortening a wire.
I build my own interconnects and I use snap on ferrite beads at the input side of my phono preamp.

That is a very good suggestion! I will ask on radio forums but I think the ferrite beads may be a very easy way to eliminate any sort of magnetic interference.

 

[radiokom]

That is a very good suggestion! I will ask on radio forums but I think the ferrite beads may be a very easy way to eliminate any sort of magnetic interference.

Aha, and this is only when cartridge is on record! WTF, sorry? Your table vibrates, find why.

 

[Whaleudder]

Aha, and this is only when cartridge is on record! WTF, sorry? Your table vibrates, find why.

the strange thing is that everything is super isolated. If it only happens when the needle is down then was the issue with the other entertainment unit just that it was not as solid as my sideboard?

is there anything common around the house that I can try to use to test isolation? I have tried putting the turntable on pillows so it’s decoupled from where it is located and that seems to not have any impact. Thank you for your help, this is really really frustrating me.

 

[Whaleudder]

https://imgur.com/a/stz8nfR

This is how it is setup at the moment. You can see that the turntable is on a pretty solid surface. That sideboard is very sturdy. How would I test to isolate the turntable without going out and buying stuff just to test with?

 

[radiokom]

https://imgur.com/a/stz8nfR

This is how it is setup at the moment. You can see that the turntable is on a pretty solid surface. That sideboard is very sturdy. How would I test to isolate the turntable without going out and buying stuff just to test with?

Your turntable is on "pretty unstable surface" what will start to vibrate from anything. Turntable should be isolated from all your equipment and not placed on bedside table. But you can test is following way (switch off your CD of course and anything inside bedside table) - lift your amplifier with your hands when cartridge is on record. To start rotation is not necessary. Simply place cartridge on record and then lift amplifier. And leave space between your bedside table and wall.

 

[Whaleudder]

Your turntable is on "pretty unstable surface" what will start to vibrate from anything. Turntable should be isolated from all your equipment and not placed on bedside table. But you can test is following way (switch off your CD of course and anything inside bedside table) - lift your amplifier with your hands when cartridge is on record. To start rotation is not necessary. Simply place cartridge on record and then lift amplifier. And leave space between your bedside table and wall.

Hello thank you for your response. I am confused a little bit about this test. Do I just put the stylus on the record, with no rotation and then lift the amp off the table? What should I be looking for/expecting when I do this.

edit: I have performed the above test with both the turntable turning and not turning and I did not see/notice any change when lifting the amp.

 

[Whaleudder]

Ok time for some out of the box thinking. I’m going to pop into town and buy a set of https://www.rockshop.co.nz/vater-buzz-kill-extra-dry-head-dampeners these. I will put one under each foot of the turn table and see if that helps with isolation. These are amazing shock absorbers so I will update once I have tried them.

 

[KingBubba]

I have a feeling that your thoughts about the steel framework may be on the money. This issue is very likely a type of feedback, but the cause is not a typical cause. Having tried everything else, have you tried going outside for a brief stereo picnic and see if the feedback continues there? Your issue is quite complicated. I hope you have luck in finding some result that helps. Good luck.

 

[Whaleudder]

I have a feeling that your thoughts about the steel framework may be on the money. This issue is very likely a type of feedback, but the cause is not a typical cause. Having tried everything else, have you tried going outside for a brief stereo picnic and see if the feedback continues there? Your issue is quite complicated. I hope you have luck in finding some result that helps. Good luck.

Stereo picnic may actually not be as silly as it sounds. The things I brought for the players feet were amazing but didn’t work for my issue. I recommend anyone having issues with a not very solid surface or a wooden floor should try them. But sadly I’m still where I was yesterday.

 

[T68]

Have you tried putting the turntable on the floor to get it on another level compared to whatever is causing the interference?

 

[heyraz]

Maybe it's something coming from the turntable's internal electronics.

Try hooking everything up as usual, put the needle in the groove (or above the groove) but for this test unplug the turntable from its power source.

 

[C Hart]

First of all, welcome @Whaleudder to the forums!

Most of this thread is making me shake my head. It really went down the rabbit hole. A cartridge acting like an antenna? EMI? Magnetic interference? Steel frames channeling waves (like Ghostbusters)?

I am sure that you have acoustic feedback of the simplest kind. The stand is resonating at 20 Hz or so. It's too tall and skinny. Break it up with a turntable isolation, an electronic rumble filter, or, probably the best solution, a shorter, heavier stand. Maybe just put a few dumbells in the cabinet and see if it improves.

That ProJect has middling rumble numbers but under most circumstances it is fine. In this case not so much. So another solution is to get a very low rumble and well-suspended turntable. I never miss an opportunity to plug vintage 1970s Technics SL1600/1700/1800s.

Feedback is a very well known problem and has been straighforward to solve since at least those Technics TTs were made.

 

[KentTeffeteller]

This issue only happens with vinyl, all other sources are fine. I have responded with component specs and my concern about the house electrical wiring going through steel framing. The change that was made was a new entertainment unit which appears to have amplified the issue to the point where it was very noticeable. Thank you for your response.


Hello and thank you for your response. I am using a Debut carbon DC turntable with an Ortofon M2 Red cartridge and stylus. These are the originals that came with the turntable. They both have less than 30 hours on them.


Thank you for your response Andy, I think you are on to something here, there could be some kind of sympathetic oscillation between the moving magnet and the steel in the entertainment unit/walls.


Hello, thank you for your response and concern. It does feel to me like there is no explanation until last night when I moved things around, now the picture is slowly becoming more clear. This is certainly not a prank however I can see how it may come across as that given how outrageous the problem is.



Thank you for your response Kirk. I moved my setup to the sideboard and got a big improvement but still have enough of an issue that it is badly effecting the sound of my system.



At one stage my leading theory was that my house must be build on an ancient burial ground. Thank you for your response.



correct. The problem seems to be environmental rather than system.

Your problem, is most likely acoustic feedback. The Pro-Ject Debut is well known for being susceptible to it. You need to install your turntable on a level surface, and on substantial furniture well away from loudspeakers to mitigate this. If your home has springy wood floors this will also be exacerbated. Hope this helps you and gives you some ideas on how to sort this.

 

[beekeo]

So I got out of bed, moved the turntable and amp both to the sideboard and tried from there. This immediately reduced the issue I have by about 75%

have you also tried combining this different location with the ifi zen phono's subsonic/warp filter as well as the isolation feet? Hit the problem on multiple fronts.
since you also said that this only happens with vinyl sources, I'm going to agree with the folks that are looking at mechanical damping/acoustic feedback as the problem. Likely the new furniture and the arrangement of components on it are exacerbating an issue that was easy to overlook previously.

 

[maxhifi]

Does the problem exist when you listen with headphones (speakers off)?

 

[heyraz]

@C Hart
A cartridge acting like an antenna? EMI? Magnetic interference? Steel frames channeling waves (like Ghostbusters)?

Not as unbelievable as you think. For example, Grado cartridges are unshielded and "The Grado Hum" is well known.

If the cartridge is unshielded, the "antenna effect" isn't so farfetched and multipath interference needs to be ruled out.
Multipath interference occurs when an RF signal from a transmitter arrives at a receiver via two or more routes.
The OP stated this all became noticeable after he got a metallic rack.

The cyclical nature of the hum is the puzzling part of the problem. To rule out the electronics of the turntable, I suggested the OP place the needle on the vinyl after the turntable has been unplugged from its AC source.

A friend of mine who is a HAM operator recently fixed his neighbors radio. He noticed immediately that a length of wire in the radio was a multiple of his antenna's bandwidth. He either looped the wire or shortened it and problem solved.

The OP's problem could be internal or external. It needs to be methodically investigated.

 

[CrSens]

Still does not make much sense what is happening, EMI/RF would normally not produce subsonics, and stop when reducing the volume. The only thing left is the volume is simply too high and affects the turntable through the air, not just surface. How loud do you listen when this happens (approx. dB level, if possible)?

 

[Fishead]

Better place for turntable is shelf

What @radiokom suggests is a good idea and not very expensive provided you have some DIY skills. It will either solve the problem or conceivably, should the issue be related to the steel construction of your home, make it much worse! In either case, you have a good chance of learning more about it and in the event that it solves the problem, you now also have a much better arrangement for the placement of your turntable. I have all my turntables on wall shelves. The 1219 is not currently in use.

B system:



And in the main system:



Nothing fancy, just some brackets from Home Depot or Lowes, then a 1/8 inch layer of foam (mainly just to keep things from sliding around) beneath a shelf of 1/2 inch plywood, then a 40lb slab of quartzite and the table on top.

You might give this solution a try since it doesn't take much to make it happen amigo.....good luck "down under....." (pun intended!)

PS - You do not need the heavy slab of stone, just a wooden shelf will do for the experiment. Sometimes I think the system sounds better with just the plywood shelf.....aaaaargh!

 

[radiokom]

So,
What we have:

1. This problem is not only with this particular turntable in your setup (?);

2. This problem exists even if turntable motor is not started;

3. This problem exists only when stylus touches record (no matter it rotates or not). If tonearm is rised, there is no noise, right?

Conclusion – turntable (and record along with it) vibrate. Turntable transformer? Who knows, simply unplug it from socket. Cartridge remains connected.

And go step by step. Of course if you have powerful ghost in your house, like Te Tapihana Tiriwa what do not like stylus tip touching record, it is impossible to resolve this problem at all.

 

[rothwellaudio]

It is only present during playback of records while the needle is down on the record itself.

This is the smoking gun.

Most of this thread is making me shake my head. It really went down the rabbit hole. A cartridge acting like an antenna? EMI? Magnetic interference? Steel frames channeling waves (like Ghostbusters)?

Yes, there have been some pretty far-out suggestions so far.

Looks to me like arm/cartridge resonance. In fact, it looks very very very much like arm/cartridge resonance.