Mark_Seaton
Ground loops and other noises from connected subwoofers and speakers is the most common issue we deal with in support.  I'm setting aside this thread for owners to post questions and for me to post and link to resources.  I'll be adding to this over time and reserving the first few posts.  I'll also be moving over some posts from other threads which had tangent discussions about such issues.

Let's start with the most important issue of answering the question of if there is something wrong with my subwoofer?

Start by unplugging any connections to the subwoofer amplifier, at the amplifier, other than the power cord.  Start with the Volume/Gain at full counter-clockwise, minimum gain.

  1. When first powering on the subwoofer with no connections to the sub, does the RED LED flash at you?  If yes, there could be an issue with the power line or fault in the amplifier.
  2. Do you hear any hum with the gain at minimum with no connections to the sub?  If Yes, contact us as there could be an internal issue with the amplifier.
  3. As you turn the gain up to 12 o'clock and toward maximum with no connections to the sub do you hear a hum? When does it increase?  If Yes, there could be either an environmental/power issue, or internal fault in the amplifier.
Next turn the volume/gain to minimum (full counter-clockwise) and add only the XLR or RCA connection with connection to the preamp or receiver being powered on (not in standby).

  1. Does the subwoofer hum as soon as you connect the XLR/RCA with volume at minimum?  If yes, you have a significant ground loop that likely comes from a satellite or cable TV interaction.
  2. Does the subwoofer hum only after you raise the volume?  If yes, you have a ground loop with a few possible sources including an ungrounded (2-prong) preamplifier/receiver, a satellite, or cable TV interaction due to those not being well connected to the power system ground.  

We'll go through a handful of tricks to make the various ground connections or separations to make all the components work happily together.  Plenty more to be added...
 
Mark Seaton
Seaton Sound, Inc.
sales@seatonsound.net
773-290-8436
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Mark_Seaton
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Mark Seaton
Seaton Sound, Inc.
sales@seatonsound.net
773-290-8436
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Mark_Seaton
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Mark Seaton
Seaton Sound, Inc.
sales@seatonsound.net
773-290-8436
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hellcat
Updated: Additional Information from SpeakerPower:

http://www.speakerpower.net/noise-reduction-in-systems.html

http://www.jensen-transformers.com/application-notes/
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audioguy
hellcat wrote:
Additional Information from SpeakerPower: http://www.speakerpower.net/noise-reduction-in-systems.html


Thanks for posting that.  Very helpful!!
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hellcat
Previous post from another thread:

The F2's are absolutely stunning in the Cherry finish.

The HT amplifier produces a hum with NO other connections other than the supplied power cable connected and powered on.

The hum "tracks" the gain in volume.

I've tried the temporary ground lift test with no success.

I have Connected the HT amplifier to "entirely" different circuits. The hum is still present.

Also have tried the Emotiva CMX-2 that is designed to remove any "dirty AC" being produced the F2 still has the hum audible 15' away.

Another note the settings are set as delivered with gain level at 12 o'clock.

I imagine the hum will become worse when the Slave unit is connected.
I'm awaiting delivery for the out of stock SpeakOn cable.

Update: The SpeakOn cable arrived today and the hum multiplied as expected.

Thank you for any advice
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audioguy
hellcat wrote:
Previous post from another thread: The F2's are absolutely stunning in the Cherry finish. The HT amplifier produces a hum with no connections other than the power cable connected and powered on. The hum "tracks" the gain in volume. I've tried the temporary ground lift test with no success. Connected the HT amplifier to other circuits with the hum still present. Also have tried the Emotiva CMX-2 that is designed to remove any "dirty AC" being produced the F2 still has the hum audible 15' away. Another note the settings are set as delivered with gain level at 12 o'clock. I imagine the hum will become worse when the Slave unit is connected. I'm awaiting delivery for the out of stock SpeakOn cable. Update: The SpeakOn cable arrived today and the hum multiplied as expected. Thank you for any advice


It sound to me like Mark needs to send you a replacement amp.  Swapping them out is a 5 minute job.  

I would text him, email him and call him.  All of my Seaton products have a VERY SLIGHT hum (from the eDSP engine) but only audible if you are right next to the driver.  The clue for me is that it increases with an increase in the gain knob.  Usually power line hum/hiss never changes.
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Mark_Seaton
audioguy wrote:

I would text him, email him and call him.  All of my Seaton products have a VERY SLIGHT hum (from the eDSP engine) but only audible if you are right next to the driver.  The clue for me is that it increases with an increase in the gain knob.  Usually power line hum/hiss never changes.


Thank you for reminding me of the next topic to add... Defining noises.

A hum is a constant tone, most commonly 60Hz, or 50Hz overseas.  A hum more or less sounds like a constant "mmmmmm".  You are referring to a hiss, which makes a "shhhh" sound, similar to that of a seashell.  There can be a third type of sound which is a buzz, which sounds a bit like a bumble-bee making a "bzzzzzz" sound.

All three are very different issues, and all suggest different fixes.  I have many times wasted hours on the phone troubleshooting noises only to find that what someone is calling a hum is in fact white noise, or it's a buzz rather than a hum.  At some point I'll have to record and post some example noises to help owners with troubleshooting so we at least have the language sorted and clear communication.
Mark Seaton
Seaton Sound, Inc.
sales@seatonsound.net
773-290-8436
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Mark_Seaton
audioguy wrote:
hellcat wrote:
Previous post from another thread: The F2's are absolutely stunning in the Cherry finish. The HT amplifier produces a hum with no connections other than the power cable connected and powered on. The hum "tracks" the gain in volume. I've tried the temporary ground lift test with no success. Connected the HT amplifier to other circuits with the hum still present. Also have tried the Emotiva CMX-2 that is designed to remove any "dirty AC" being produced the F2 still has the hum audible 15' away. Another note the settings are set as delivered with gain level at 12 o'clock. I imagine the hum will become worse when the Slave unit is connected. I'm awaiting delivery for the out of stock SpeakOn cable. Update: The SpeakOn cable arrived today and the hum multiplied as expected. Thank you for any advice


It sound to me like Mark needs to send you a replacement amp.  Swapping them out is a 5 minute job.  


I'll be adding to the first post and clarify that if you have a YES to getting noise with any of the first 3 issues, no grounding of other components is going to fix the issue, so save yourself the frustration.  About the only other thing to try are outlets on entirely different circuits or disconnecting known noisy devices like DirecTV power supplies or lighting dimmers.

As mentioned in the previous posts that appear to have been lost in the attempt to move them, there is some internal issue that we have observed in 2 customer's homes thus far and can't replicate at our facility or SpeakerPower.  The fix will come in the forum of a replacement amplifier, but we are narrowing down the fix with the other customer, as grabbing another amp from the shelf won't change the result.

Mark Seaton
Seaton Sound, Inc.
sales@seatonsound.net
773-290-8436
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rajkwarrier
I have a hiss from all my catalysts audible from about 2 ft. It does not change with changing the gain. This occurs even with the xlr cables disonnected. I have my speakers connected to a Furman Dsp mini 20 relay. I usually hear a pop when the speakers turn on. I called Mark and he reassured me that it was the relay and not concerning.
I have sent my Marantz av7702 to service to ensure that was not the cause.
Unfortunately, even with nothing connected and all the theater led lights off, I hear the hiss.
When the speaker turns on, the red Led on the back of the speaker lights up but does not stay on.
My speakers are ion dedicated circuits but they do share the ground for the house.
Any help dealing with this is appreciated. Not even sure if there is any cause for concern.
Thanks
Rajesh
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Mark_Seaton
rajkwarrier wrote:
I have a hiss from all my catalysts audible from about 2 ft. It does not change with changing the gain. This occurs even with the xlr cables disonnected. I have my speakers connected to a Furman Dsp mini 20 relay. I usually hear a pop when the speakers turn on. I called Mark and he reassured me that it was the relay and not concerning. I have sent my Marantz av7702 to service to ensure that was not the cause. Unfortunately, even with nothing connected and all the theater led lights off, I hear the hiss. When the speaker turns on, the red Led on the back of the speaker lights up but does not stay on. My speakers are ion dedicated circuits but they do share the ground for the house. Any help dealing with this is appreciated. Not even sure if there is any cause for concern. Thanks Rajesh


This is the residual noise floor of the DSP & amplifiers in the Catalyst while connected to a 99dB@2.8V/1m tweeter, and is entirely normal.  In many rooms you have to be 1' away to hear it, in some very quiet rooms it is easier to hear.  Every component has some noise floor which the connected speakers then convert to sound.  With low power, low efficiency speakers this is almost never an issue, but when an efficient speaker adds 6-20dB to the background level it can become audible in some cases.  Typically this is not audible or only very faintly audible at the listening position.  The sound should be a white noise similar to what you would hear with your ear up to a seashell.
Mark Seaton
Seaton Sound, Inc.
sales@seatonsound.net
773-290-8436
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rajkwarrier
Thanks Mark,
Is there any concern about the red led lights flashing when the speakers turn on and go off?
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Mark_Seaton
rajkwarrier wrote:
Thanks Mark, Is there any concern about the red led lights flashing when the speakers turn on and go off?


There might be some variation between newer and older amplifiers, but it's common to see a blip or one flash of the red LED during power up or power down.
Mark Seaton
Seaton Sound, Inc.
sales@seatonsound.net
773-290-8436
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Kasofo
Mark_Seaton wrote:
audioguy wrote:
Previous post from another thread: The F2's are absolutely stunning in the Cherry finish. The HT amplifier produces a hum with no connections other than the power cable connected and powered on. The hum "tracks" the gain in volume. I've tried the temporary ground lift test with no success. Connected the HT amplifier to other circuits with the hum still present. Also have tried the Emotiva CMX-2 that is designed to remove any "dirty AC" being produced the F2 still has the hum audible 15' away. Another note the settings are set as delivered with gain level at 12 o'clock. I imagine the hum will become worse when the Slave unit is connected. I'm awaiting delivery for the out of stock SpeakOn cable. Update: The SpeakOn cable arrived today and the hum multiplied as expected. Thank you for any advice


It sound to me like Mark needs to send you a replacement amp.  Swapping them out is a 5 minute job.  


I'll be adding to the first post and clarify that if you have a YES to getting noise with any of the first 3 issues, no grounding of other components is going to fix the issue, so save yourself the frustration.  About the only other thing to try are outlets on entirely different circuits or disconnecting known noisy devices like DirecTV power supplies or lighting dimmers.

As mentioned in the previous posts that appear to have been lost in the attempt to move them, there is some internal issue that we have observed in 2 customer's homes thus far and can't replicate at our facility or SpeakerPower.  The fix will come in the forum of a replacement amplifier, but we are narrowing down the fix with the other customer, as grabbing another amp from the shelf won't change the result.

Not sure that this is going to help anyone but I have an F2+ and an F2 slave and at initial hook-up had the + plugged into my power conditioner and had no audible hum. After doing the dreaded sub crawl I had to change the position of the F2's and immediately had a hum that followed the gain/volume control. I had plugged into a "grounded" outlet on a different circuit but still had the issue. Moved to different outlets and no change. Finally, got an extension back into the power conditioner and no hum! My pre/pro is a Marantz 7702MKII if that helps anyone...
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rajkwarrier
I don't use a power conditioner. Looks like it may not help the speaker hiss that I am experiencing considering it's the inherent amp noise.
What type of power conditioner are you using? Do you use any for the catalysts?

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Kasofo
It is a Monster HTS 5100 MKII Power Conditioner and I do not have the Catalyst's for mains but have Def-Tech ST-L Super Towers. They are not plugged into the Monster 5100 but are plugged into a basic surge protector. 

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farsider3000
I'm coming into the thread late but have you tried a ground loop isolator designed for cable tv?  I have two of the Seaton Submersive HP+ and I had a hum that I narrowed down to the cable tv cable.  Once I put the ground loop isolator on the incoming cable tv cable, no more hum.

Before adding the Seaton's to my theater my room was deadly quiet so it was a very noticeable hum and I was not happy.  Interestingly my pair of JL Audio F112 do not produce hum due to the cable tv cable. 

Hope this helps.

You can find them on Amazon.com:

TII 220 Ground Loop Isolator for Cable TV applications

or

Viewsonics VSIS-EU Cable TV Ground Loop Isolator

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hellcat
Hello farsider3000,
The hum is audible at least 14' without any connections other than the included power supply cable.
Hum is still present with all circuit breakers off except the dedicated circuit for the subwoofer and only with the F2's connected to the circuit without any other connections or any other components connected as well.

The transformers do a great job isolating coax cable ground issues. I use Jensen Transformers and highly recommend them to others as well.
I've tried every option available other than a replacement amplifier.
My HT was silent prior to adding The F2 +/-combination.
This hum is more than distracting for an exceptional product and the F2's are truly beautiful in the finish Vintage Cherry.
The other owners post with the same issue was lost while being transferred while creating this thread.
I'm positive the amplifier has a issue with all testing taken into consideration.
Hopefully Mark will have a solution for this hum issue.
The F2's are less than 2 months old with the new HT amplifier.

I Greatly appreciate your recommendation and time.
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farsider3000
Hellcat,

Sorry to hear that.  I assume you have contacted Mark and that he will take care of it.
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Mark_Seaton
hellcat wrote:
Hello farsider3000, The hum is audible at least 14' without any connections other than the included power supply cable. Hum is still present with all circuit breakers off except the dedicated circuit for the subwoofer and only with the F2's connected to the circuit without any other connections or any other components connected as well. The transformers do a great job isolating coax cable ground issues. I use The Jensen Transformer and highly recommend the Jensen to others as well. If you read my previous post you'll notice I've tried every option available other than a replacement amplifier. My HT was silent as well prior to adding The Seaton Sound F2's + Slave Subwoofer combination. This hum is more than distracting for an exceptional product and the F2's are truly beautiful in the finish Vintage Cherry. The other owners post with the same hum issue was lost while being transferred by Mark while creating this thread. I'm positive the amplifier has a issue with all testing taken into consideration. Hopefully Mark will have a solution for this hum issue. These F2's are less than 2 months old with the new HT amplifier. I Greatly appreciate your recommendation and time.


Sorry for the delay on this.  We should have something figured next week.  This rare issue has been very hard to reproduce and troubleshoot, but we are working on a few things and at minimum can get you a replacement next week to try. We'll be following up directly by e-mail or phone.
Mark Seaton
Seaton Sound, Inc.
sales@seatonsound.net
773-290-8436
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hellcat
hellcat wrote:


Sorry for the delay on this.  We should have something figured next week.  This rare issue has been very hard to reproduce and troubleshoot, but we are working on a few things and at minimum can get you a replacement next week to try. We'll be following up directly by e-mail or phone.


Mark,
Thank you for the replacement amplifier. This 2016 production model received a few internal changes which has significantly reduced (unless DSP programming has changed) the audible hum previously experienced with the initial 2015 production model.


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sthomps
Mark

Can you please contact me via pm?  I've left several voice mails and emails concerning this subject on a Submersive and have not received any response.

Thanks
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hoot
Ever since I sold my Catalysts and got away from active speakers I have ZERO hum, buzz or anything. I spent a lot of time and money installing separate circuits and fiddling with light dimmers before finally getting it down to mostly just a hiss. For audiophile listening, any noise is unacceptable. Maybe for HT movies the hiss isn't an issue and loud listening but for audiophile listening, forget it. I still have my HP+ subs. I do get thumps when switching on the lights or the ceiling fan but overall the subs are quiet. Glad there arent tweeters in them lol.
Mark you also might want to improve your communication as I know I personally had a difficult time with you when I purchased the Cats and I am still seeing people complaining about being unable to get things resolved.
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audioguy
hoot wrote:
Ever since I sold my Catalysts and got away from active speakers I have ZERO hum, buzz or anything. I spent a lot of time and money installing separate circuits and fiddling with light dimmers before finally getting it down to mostly just a hiss. For audiophile listening, any noise is unacceptable. Maybe for HT movies the hiss isn't an issue and loud listening but for audiophile listening, forget it. I still have my HP+ subs. I do get thumps when switching on the lights or the ceiling fan but overall the subs are quiet. Glad there arent tweeters in them lol. Mark you also might want to improve your communication as I know I personally had a difficult time with you when I purchased the Cats and I am still seeing people complaining about being unable to get things resolved.


I still had hum after switching to passive speakers but in my case, it was the Marantz 7702.  Once I replaced that, hum was virtually non-existent as it was prior to getting the 7702.  It can be tricky sometimes to find and eliminate the source of hum.
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motogp34
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