Author Topic: RFI? (Read 7915 times)

Lancito · « **on:** May 13, 2008 at 08:30 PM »

I noticed a few minutes ago that my REL subwoofer is receiving a radio frequency (RF). I am not sure though if its AM or FM. I'm using Ixos shielded subwoofer cable to the receiver but I still get the problem. Even if my avr is on stand-by, problem persists. But if I unplug the power cord of the AVR, RF disappears.

Please help how to remedy. Tnx.

Lance

Ctlim · « **Reply #1 on:** May 14, 2008 at 12:26 AM »

try plugging it muna to a different part / socket of the house and see if the problem persists.

ATJr. · « **Reply #2 on:** May 14, 2008 at 09:57 AM »

either you are too close to an FM or AM transmitting station....or maybe a cb radio very close to your place.....

hmmmm...if you are plugged in to the BADA which is supposed to filter these RFI out then it is not doing its job.....

try plugging in direct to the wall outlet and see what gives...

Ctlim · « **Reply #3 on:** May 14, 2008 at 10:07 AM »

Quote from: TonyT on May 14, 2008 at 09:57 AM

hmmmm...if you are plugged in to the BADA which is supposed to filter these RFI out then it is not doing its job.....

naku...

lance, would appreciate an update on this problem.

Ctlim · « **Reply #4 on:** May 14, 2008 at 11:52 AM »

try another outlet somewhere in the house... and see if the problem persists... also dry to plug them both direct (w/o the LC) and see what happens.

JojoD818 · « **Reply #5 on:** May 14, 2008 at 11:57 AM »

slow down guys, this is very weird. a sub with all its lpf receiving RF?

Lance, can you describe this RF you hear a little bit more...

If you remove the input signal to your sub (coming from your AVR), does it go away?

mars · « **Reply #6 on:** May 14, 2008 at 12:31 PM »

Bro, I used to have the same problem whenever I plug in some microphones to my mixer which are connceted to my system. May lumalabas na radio broadcast. What I did was that I tried out an extension cord with a surge protector/line filter (I can't remember the brand, but it's in Ace hardware. Costs over P300 lang) and the interference disappeared. Back then, I bought it just to have an extension cord with a surge protector. Turned out that I got a good bonus which solved a problem that has been racking my brains for over a year.

audiojunkie · « **Reply #7 on:** May 14, 2008 at 12:51 PM »

it might be in your extention or power cord that getting the signal...

JojoD818 · « **Reply #8 on:** May 14, 2008 at 01:10 PM »

Quote

But if I unplug the power cord of the AVR, RF disappears.

ground loop. do you have all your units grounded to earth?

more info please.

"Help Us Help You"

Ctlim · « **Reply #9 on:** May 14, 2008 at 02:21 PM »

how about using it without the bada? does it go away?

Ctlim · « **Reply #10 on:** May 14, 2008 at 02:49 PM »

I dont think its the problem of your ixos sub-w cable... some are able to get by on regular rca jacks nga e.

But lets just say that it is, then thats an expensive lesson on buying expensive ic's.

Sorry I don't use the ground of the LC, wala naman akong problem with anything on both systems. Though I use 2 Xindak LCs (replaced by Bada LC)

I think I could ground from inside the walls of the sockets or through the window grills, but I have not tried it yet. My guess is the problem is somewhere in the power section lines.

Full HD 3D · « **Reply #11 on:** May 14, 2008 at 03:09 PM »

Quote from: Lancito on May 14, 2008 at 07:36 AM

It's plugged in my Bada LC with the rest of the system. Kinda weird this is happening.

Base on my experience with rel. its not the power. I think its the neutrik connector negative(Black) not tap properly since its a ground, that is if you are using this connector too. This was base on what i experienced before. RELative. What model is that? Sarap ba ng REL.Hehe

Platinum · « **Reply #12 on:** May 14, 2008 at 03:39 PM »

Hi Lance, In my experience with REL Strata5, all supplied connectors by REL worked best.
I tried the Ixos before but bass sounded muddy, and just returned to the thin-type REL-supplied cables and sounded superb.
Richard E. Lord aka REL did his homework well. Just my two cents....

Full HD 3D · « **Reply #13 on:** May 14, 2008 at 10:39 PM »

Quote from: Platinum on May 14, 2008 at 03:39 PM

Hi Lance, In my experience with REL Strata5, all supplied connectors by REL worked best.
I tried the Ixos before but bass sounded muddy, and just returned to the thin-type REL-supplied cables and sounded superb.
Richard E. Lord aka REL did his homework well. Just my two cents....

UUY!!! Another RELative. Yes, he really did his work well in providing a real "sub"

Full HD 3D · « **Reply #14 on:** May 14, 2008 at 10:42 PM »

Quote from: Lancito on May 14, 2008 at 03:41 PM

Thanks Platinum! But my REL was supplied only with the neutrik and no rca connector. Maybe because this is a Chinese REL and entry level.

Does REL sub come from China?

I think its best to contact Ferdi, he can help. He is a nice guy. Hope this help.

JojoD818 · « **Reply #15 on:** May 15, 2008 at 02:12 AM »

Quote from: Lancito on May 14, 2008 at 02:12 PM

I hear a very faint thumping/bass/music coming out of the subwoofer. It is not LOUD but when you turn off the a/c, shut the windows, and listen to it really close, it's there.

When I disconnect the subwoofer cable from the avr in off/standbye or cable from sub, nawawala. When I unplug the avr even if the subwoofer cable is connected to the avr, nawawala ulit. Labo noh?

I don't know if grounding my Bada as in running a copper wire from the LC to the window frame of my room is considered grounding.

Probably I need to do real grounding. Pano ba?

Ok, here is what I'll do. Forget grounding and your Bada muna.

Connect your Ixos to the Rel but donot connect it to your AVR, pag wala RF ok ang sub and Bada. My suspect is your AVR's sub out, I noticed kasi when you turn it on or in standby meron RF, but when you unplug your AVR from mains line or disconnect your Ixos from the AVR wala din.

To really make sure, eliminate possible suspects by using your REL on another AVR if possible, or if you have an audio setup, try plugging in your Ixos to a preamp output and see if the RF is still there. After you completely eliminate your Bada and REL, the only thing left on the other side of the equation is your AVR.

ATJr. · « **Reply #16 on:** May 15, 2008 at 04:46 AM »

Quote

I dont think its the problem of your ixos sub-w cable... some are able to get by on regular rca jacks nga e.

But lets just say that it is, then thats an expensive lesson on buying expensive ic's.

well, ............experience is the best teacher...

i believe this has something to do with the design of the input stage of your REL sub, a ferrite bead at the input of the first amp will help but this will entail opening it up and warranty will be voided...

the cables act as antenna and the input stae of the REL as detector, nothing mysterious here.....natapat lang sa yo...

streetsmart · « **Reply #17 on:** May 15, 2008 at 09:05 AM »

Quote from: TonyT on May 15, 2008 at 04:46 AM

well, ............experience is the best teacher...

i believe this has something to do with the design of the input stage of your REL sub, a ferrite bead at the input of the first amp will help but this will entail opening it up and warranty will be voided...

the cables act as antenna and the input stae of the REL as detector, nothing mysterious here.....natapat lang sa yo...

Tony, if this is true, then the problem should appear if the REL has power and even if it is not connected to the AVR. Am I correct?

On the other hand, Lancito says that the problem disappears when he removes the connection to the AVR so the problem seems to be different. Of course, I assume may power ang REL when it is unplugged from the AVR.

diy_master · « **Reply #18 on:** May 15, 2008 at 09:20 AM »

try to check this bro, 1. baka may malapit na radio station sa lugar mo. 2. yung wire mo naka create ng coil type or design ng same frequency antenna. 3. may coil sa sub mo na same specs ng radio receiver. 4. yung elecrtonic x-over ng sub mo may rf control na tumapat sa frequency ng radio.

note: fm radio antenna, look like curly hair made of magnetic wire.
: am radio antenna made of ferite bar, winding with thin hair size magnetic wire.

conclusion: Better check the internal of your sub amp.

ty!

ATJr. · « **Reply #19 on:** May 15, 2008 at 09:42 AM »

or you can try to have that REL unit replaced and see if the intereference is gone...

JojoD818 · « **Reply #20 on:** May 15, 2008 at 12:28 PM »

I beg your pardon but I doubt it if the problem is in the input section of the sub for any decent sub contains redundant/cascaded lpf in it's frequency filter section also located in it's input. Now if for example the rf noise is being received in the sub's input via porous rf transmissions then it should have been filtered out.

The only way for rf, am/fm or whatever radio signals to pass is if it is forcedly injected as an input signal, which leads me to suspect the AVR.

Although I'm not discounting the fact that the AVR + Ixos cable + REL sub accidentally forms an RF receiver, anything is possible.

Lancito,

If the rf problem is local to your AVR's sub out, one way of really checking this is to use the AVR's sub out and connect it to an integrated amp with speakers (even one channel only), this way we can be sure if the problem is really from the AVR or not...

Ctlim · « **Reply #21 on:** May 15, 2008 at 05:19 PM »

tsk tsk... then I believe the next step is to try it out in another house..

JojoD818 · « **Reply #22 on:** May 15, 2008 at 08:34 PM »

Quote from: Lancito on May 15, 2008 at 04:48 PM

Thanks for all the help guys.

Just an update, I moved my sub from its original location to see if there is improvement. Happy to say that the volume of RF has come to a minimum. However, I now experience an occasional "thud" when I leave the REL on while it is connected to the AVR in standbye mode. Also, since the T1 is downward firing, I put my hand on the cone and I can feel it moving. There is a pulse or movement of the cone. Is this normal?

I also tried plugging it directly to the wall outlet without LC. The sound became worse. Therefore, the BADA is not to blame.

Medyo badtrip nako sa REL ah. I doubt Ferdie will replace this with a new one.

There shouldn't be any movement when there is no signal. The only thing I can think of regarding cone movement without any signal is it is coming from the AVR, or the sub's amp is oscillating.

There you go, you've just eliminated one of your variables which is the Bada.

Sir, being badtrip is your worse enemy, you won't be able to think straight so cool lang.

JojoD818 · « **Reply #23 on:** May 15, 2008 at 09:16 PM »

Quote from: Lancito on May 15, 2008 at 09:07 PM

Thanks Jojo! There is definitely movement of the cone even with no signal. Starting to be very annoying.

1. If the signal which causes the cone movement is coming from the AVR, what should i do?

2. What does "oscillating" mean? How can I fix this?

Thank you all.

1. First, you should be absolutely sure that the cause for the cone movement is coming from your AVR. If you remove the rca plug coming from your AVR and the cone movement is still there, then it is definitely not coming from the AVR. This isolates the AVR and our efforts should then be focused on your sub. Another way to test this is to borrow another sub and try it in your AVR.

2. In simple terms, oscillation is simply instability in your sub's amp section which can be caused by several factors. There is no user fix for this, a trip to the distributor is a must.

Lancito · « **Reply #24 on:** May 15, 2008 at 09:46 PM »

Quote from: JojoD818 on May 15, 2008 at 09:16 PM

1. First, you should be absolutely sure that the cause for the cone movement is coming from your AVR. If you remove the rca plug coming from your AVR and the cone movement is still there, then it is definitely not coming from the AVR. This isolates the AVR and our efforts should then be focused on your sub. Another way to test this is to borrow another sub and try it in your AVR.

2. In simple terms, oscillation is simply instability in your sub's amp section which can be caused by several factors. There is no user fix for this, a trip to the distributor is a must.

1. I am now absolutely sure that the cone movement only happens if the subwoofer cable is connected to the AVR. Whether the AVR is on or off, cone movement is there. But when I unplug the IC from the AVR, movement is gone.

How can I solve this? Any ideas?

HELP pare!

JojoD818 · « **Reply #25 on:** May 15, 2008 at 10:02 PM »

Quote from: Lancito on May 15, 2008 at 09:46 PM

1. I am now absolutely sure that the cone movement only happens if the subwoofer cable is connected to the AVR. Whether the AVR is on or off, cone movement is there. But when I unplug the IC from the AVR, movement is gone.

How can I solve this? Any ideas?

HELP pare!

Ok, so we redirect our attention to your AVR and Ixos IC. Is this the only IC that you can use to connect your sub? Would you happen to have another sub in the house that you can connect to your AVR's sub out?

The reason for changing ICs is because some exotic/specialty cables exhibit increased capacitance which when combined with the right ingredients can cause a lot of headaches.

Do this first, if after changing ICs (or using another sub) and the cone movement is still there, then the AVR is the one that needs to take a trip to the distributor.

Lancito · « **Reply #26 on:** May 16, 2008 at 08:15 PM »

Thanks Jojo for the help.

I spoke to the REL Ferdie Ludo this evening. It seems that there is a big chance the AVR is at fault since the popping/thumping sound only occurs when the IC is connected to my Denon. REL also said that if the subwoofer is the problem, it will exhibit the sound even if the IC is not connected. I reset my AVR and observe ko muna from there. Will let you know of any developments.

JojoD818 · « **Reply #27 on:** May 16, 2008 at 10:49 PM »

Quote from: Lancito on May 16, 2008 at 08:15 PM

Thanks Jojo for the help.

I spoke to the REL Ferdie Ludo this evening. It seems that there is a big chance the AVR is at fault since the popping/thumping sound only occurs when the IC is connected to my Denon. REL also said that if the subwoofer is the problem, it will exhibit the sound even if the IC is not connected. I reset my AVR and observe ko muna from there. Will let you know of any developments.

Best of luck bro, hope it's just a glitch on your AVR...

Lancito · « **Reply #28 on:** May 17, 2008 at 10:49 PM »

Problem solved. After I reset the AV receiver, everything went back to normal. No more popping, humming, and RFI. Thanks to all those who helped.

Lance

streetsmart · « **Reply #29 on:** May 18, 2008 at 07:48 AM »

How did you do the reset?