High-Pitched sound in recordings and speakers with a Zoom-R16 when connected USB-Ethernet

[robertkjr3d]

I'm hearing some sort of high-pitched, around 12Khz sound in the speakers and in the recordings from my 'Zoom-R16'. At first I was trying to blame everything else... Than come to find out after unplugging the USB-Cable that routes to my computer, the sound goes away.

I don't want to be stuck just using the SD-Card on the 'R16'. My desktop-computer and where the 'R16' are wired-up is in two different rooms.

I'm using this USB-over-Cat6 extender:
https://www.amazon.com/gp/product/B08CZ925XB/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
I've not had any problems with this extender before this incident. We use it for connecting Joysticks and playing other video-games and stuff.

What I'm really asking here is: I have 6 (1/4th) cables connected to my 'R16'...
They are all unbalanced . If they were converted to balanced, would that correct the issue? maybe.. Trying another Extender... is a also maybe?

Oddly, its not a ground-loop sound of 60hz humm. Its some electrical noise... Any thoughts...

[James Perrett]

What speakers are you using? Are they grounded? Do you hear the sound with nothing connected to the Zoom apart from the USB and a pair of headphones? It might help if you could draw a diagram of exactly what you have connected and what sort of cables you are using to connect them. It is almost certainly some kind of grounding problem but it could be a lack of ground rather than a ground loop.

[robertkjr3d]

What speakers are you using? Are they grounded?.

Its Onkyo tx-nr686 connected with Klipsch speakers... Grounded? I'm not sure what that means in this case, except that the Onkyo and the powered Sub-Woofer are plugged into 'Grounded' circuits.

As I said the sound goes away as soon as I unplug the USB cord. I can even make recordings with the Zoom without the USB. Without the high-pitch sound onto the SD-Card.

The diagram will possibly make you flip....

Here is a one-Channel diagram, but keep in mind there is 5-like this. and a 6th channel if you include the sub-channel that also comes through.

https:*?*?*/47TRPMM
It uses a 'Russound ADP 1.2'. To convert speaker-line output to RCA that is connected into the 'Zoom-R16'.

'Left', 'Right', 'Center', 'Sub', 'Rear-Left', 'Rear-Right'. 5.1CH Sound.

My current recordings using my built panel-box are starting to be decent. However, when using the computer with a DAW, I was getting the 'high-pitch' sound. I can edit it out.

Another issue I haven't been able to solve is... But may be totally unrelated is: I'm getting an unacceptable amount of pops and clicks.

Edit: I keep trying to post image. and it keeps failing. I've tried different methods. Here i'm trying just an url.

[James Perrett]

What happens if you disconnect the R-16 from the receiver and listen through headphones plugged into the R-16? Do you hear any noises with the USB connected?

Are you trying to record the outputs from the Onkyo receiver?

[robertkjr3d]

What happens if you disconnect the R-16 from the receiver and listen through headphones plugged into the R-16? Do you hear any noises with the USB connected??

Actually, if you looked at the diagram of my box I've built. In 'Record' mode, no 'speakers' are connected at all. But the 'high-pitch' sound shows up in the recording. I'm not using the outputs on the 'R16', if thats what your referring to. Its just being used for recording.

Are you trying to record the outputs from the Onkyo receiver?

Yes that's it exactly. That is the purpose of the box, for multi-channel recording. 1) routed to my regular speakers.... 2) switched to routing into the 'Zoom-R16'.

I can also produce the issue this way too:
1) I switch the hdmi on the onkyo receiver to 'my Roku' (not my computer). But play nothing. It is silent.
2) my box is still set to send the audio to the speakers (not the Zoom-R16). So Zoom-R16 interconnects are in theory connected to nothing. There is a Pos switch and a Neg Switch. When that side is switched off, there should be no cross-talk. (in theory)
3) I connect Zoom-R16 to the USB-Extender that connects to my Desktop Computer.
a) I still hear nothing.
4) But then I start Cubase-LE
a) Boom the sound starts in the speakers. I must be getting cross-talk. Somehow! On #2.
b) the speakers are not connected to the Zoom (again in theory... here)

[Mike Stranks]

Edit: I keep trying to post image. and it keeps failing. I've tried different methods. Here i'm trying just an url.

This little video may help: https://youtu.be/s7vVDGTOHW0

[Sam Spoons]

Hopefully you'll manage to get the diagram you mention posted (but a link will work fine to the actual image). Either way a detailed explanation of the setup, it's purpose and the gear in use would help. There may be other ways of achieving the same result.

FWIW you are recording 5.1 surround sound? What is the context/reason for this? Is it in a domestic application, a church/venue or what?

[robertkjr3d]

That link is posted. (see Post 2) It works... tested in non-logged in browsers. (the posts are a bit out of order, because of posting approvals)
I'm not sure I understand the dilema on that one. I believe I realized the img--link issue was I should have used the BBCode link. But by that time, I couldn't edit it again.

Purpose of my Box?: Simple... I've built a box to collect multi-channel recordings. Normally I've been using Blu-Rays. But in 2021, I've been finding a way to collect from streaming sources.
You can find-'capture' cards that might claim to work, but then you have to worry about HDCP issues. Then they are also very expensive, for the ones that may work in multi-channel, and may not be very good quality. So how to solve:

Capture the speaker-line level output, and convert to line-level. For each-channel.
This solution uses 'Russound-ADP-1.2'. Then record with the 'Zoom-R16'.

My best test recording. Is still not acceptable. But does still give me the gooses. It is recorded with very-high fidelity and matching of the original source quality. I've been testing with 'Star Trek: First Contact' opening theme.

Problems:
1) 'When using the computer with Cubase'... I need to edit out the 12hz noise. super faint.
2) I'm getting an unacceptable amount of pops and clicks. There really is no acceptable amount. Maybe one click in 5mins. Or an entire recording...
a) I get the pops and clicks when recording with the SD-Card.... too
b) of course the SD-Card is limited to 44,100. No high-pitch happens though.
3) I was just talking to the 'Russound' manufacturers. It seems that they may be built crossing the 'Negative' wires for the two sides. Sometimes referred to as a 'Common Ground'. That pollutes the quality. The onkyo is not a 'common-ground' receiver. If this is true: I'll just buy two more of them. and only use one side on each.

There may be another possible reason for high-pitch-crosstalk...
The computer would not engage the driver for the R16, until Cubase starts. Then it may try to send something down back to the Onkyo... but but... we are only talking electrics here and not sound. Yes it is connected with a HDMI cable. But the onkyo, hadn't even selected to be using it.

[Sam Spoons]

The pic only shows a single channel coming out of the receiver to the box? I can't understand what the switches are doing, I'm guessing selecting Left +ve or -ve to the 'normal speakers' with the other to the Zoom but I still don't understand what you are trying to achieve?

[robertkjr3d]

The pic only shows a single channel coming out of the receiver to the box?

I did not want to show an exhaustive duplicative diagram. This is just a simple diagram of the Left-channels-path.
The other 4-channels have exactly the same path... (Right, Center, Rear-Left, Rear-Right)
The sub-woofer is also switched, but already comes in 'line-level' and does not to go through a 'Russound'. This image was in-progress, before some plastic around some wires and stuff:

I can't understand what the switches are doing,

There are actually 12-switches in total. The original design had 6. I would really rather have just 1. Because when I use the switches on the box. I switch all of them one way or the other. They are on-on 3-wire switches. The path goes one way or the other. Since I'm hijacking my Onkyo speaker outputs. The normal setting for the switches is to allow the path to go straight to the speakers. The other 'On' side is 'record' mode. In which you turn off the 'speakers', then the audio is sent through the 'russound' devices.

I still don't understand what you are trying to achieve?

hmm... well understanding isn't really required. I tried to say, I keep multichannel recordings. I mentioned the opening theme to 'Star Trek First Contact'.

[Drew Stephenson]

Just to be clear, we're not mixing speaker level and line level signals here are we?

[Sam Spoons]

The pic only shows a single channel coming out of the receiver to the box?

I did not want to show an exhaustive duplicative diagram. This is just a simple diagram of the Left-channels-path.
The other 4-channels have exactly the same path... (Right, Center, Rear-Left, Rear-Right)
The sub-woofer is also switched, but already comes in 'line-level' and does not to go through a 'Russound'. This image was in-progress, before some plastic around some wires and stuff:

I can't understand what the switches are doing,

There are actually 12-switches in total. The original design had 6. I would really rather have just 1. Because when I use the switches on the box. I switch all of them one way or the other. They are on-on 3-wire switches. The path goes one way or the other. Since I'm hijacking my Onkyo speaker outputs. The normal setting for the switches is to allow the path to go straight to the speakers. The other 'On' side is 'record' mode. In which you turn off the 'speakers', then the audio is sent through the 'russound' devices.

Ok I get the speaker/switch wiring now, thanks.

I still don't understand what you are trying to achieve?

hmm... well understanding isn't really required. I tried to say, I keep multichannel recordings. I mentioned the opening theme to 'Star Trek First Contact'.

Sorry but without understanding your purpose how can we offer useful advice?

But, if you just want to get 5.1 soundtracks into a computer there must be much easier ways than this? A quick google of "ripping 5.1 DVD soundtracks?" threw up several pages of software solutions (disclaimer - legality possibly dubious)

[robertkjr3d]

Just to be clear, we're not mixing speaker level and line level signals here are we?

I'm using this apapter:
https://www.russound.com/products/audio-systems/multi-room-controllers/expansion-devices/adp-1-2-speaker-to-line-level-adapter
On each of the 5-channels that come in 'speaker-level'.

However (and likely totally unrelated to the high-pitch sound, or clicks and pops)...
the left & right channels are paired... on a Russound
the Rear-Left & Rear-Right are paired...
And I've heard word that it may be mixing the 'negative' channel. (Like a common-ground) That will have an impact on sound-quality, because the receiver is not-common-ground.

Note: The 'Center-Channel' is connected to just one-side of a 'Russound' by itself.

[robertkjr3d]

But, if you just want to get 5.1 soundtracks into a computer there must be much easier ways than this? A quick google of "ripping 5.1 DVD soundtracks?" threw up several pages of software solutions

Taking multichannel audio from a DVD or Bluray is childsplay compared to getting multi-channel audio from a 'Streaming-Source'. Google that... these recordings are for me. I don't send them out.

[Sam Spoons]

But, if you just want to get 5.1 soundtracks into a computer there must be much easier ways than this? A quick google of "ripping 5.1 DVD soundtracks?" threw up several pages of software solutions

Taking multichannel audio from a DVD or Bluray is childsplay compared to getting multi-channel audio from a 'Streaming-Source'. Google that... these recordings are for me. I don't send them out.

Ah, yes, understood. I still think a software solution would be less difficult to achieve and there are apps that will allow you to download or record streamed video from which you could then extract the soundtracks. But that's not the question you came to ask so...

Some kind of transformer isolator would be the next step. Something like these would probably get the job done https://www.amazon.co.uk/10pcs-600-Isolation-Transformer-Transformers/dp/B07TLJV3WP/ref=sr_1_10?adgrpid=67139725321&dchild=1&gclid=EAIaIQobChMIouSd7M7h7gIV0d_tCh3IEwy9EAAYASAAEgKDl_D_BwE&hvadid=318138422141&hvdev=c&hvlocphy=2826&hvnetw=s&hvqmt=b&hvrand=4461534903128721514&hvtargid=kwd-303307603423&hydadcr=5088_1827856&keywords=audio+isolation+transformer&qid=1613039091&sr=8-10&tag=googhydr-21

[Drew Stephenson]

I'm wondering if this whole thing isn't just the symptoms of a ground loop that's being broken when the Zoom is disconnected?

[Hugh Robjohns]

I'm hearing some sort of high-pitched, around 12Khz sound in the speakers and in the recordings from my 'Zoom-R16'. At first I was trying to blame everything else... Than come to find out after unplugging the USB-Cable that routes to my computer, the sound goes away.

It will almost certainly be a ground-loop created between your computer and the Receiver via the Zoom and that nightmare of a switching box.

A ground-loop is virtually guaranteed in that situation with unbalanced connections and separated grounded devices at each end of the chain.

The simplest solution would be, as has been suggested, some line-level transformer isolation boxes in the unbalanced feeds to the Zoom, to break the ground connections between the computer>usb>zoom and the Receiver>switch panel.

[robertkjr3d]

Some kind of transformer isolator would be the next step. Something like these would probably get the job done https://www.amazon.co.uk/10pcs-600-Isolation-Transformer-Transformers/dp/B07TLJV3WP/ref=sr_1_10?adgrpid=67139725321&dchild=1&gclid=EAIaIQobChMIouSd7M7h7gIV0d_tCh3IEwy9EAAYASAAEgKDl_D_BwE&hvadid=318138422141&hvdev=c&hvlocphy=2826&hvnetw=s&hvqmt=b&hvrand=4461534903128721514&hvtargid=kwd-303307603423&hydadcr=5088_1827856&keywords=audio+isolation+transformer&qid=1613039091&sr=8-10&tag=googhydr-21

Ahh... yes now we are getting somewhere. Late last night I tried putting old-radio-shack Ground-Loop Isolators (not sure if that is similar to these in some way). I did see the noise had stopped. However, the sound quality also dropped. Also I'm still getting the pops/clicks. Those Ground-loop isolators only last for so long with use, in fact... I noticed I could only use one side on some to stop the noise. So likely, maybe some or all of the channels were just bad. They were all over 15 years old, sitting in a bend.

I am also trying to read-up on 'Impedance' and seeing if I was just totally mis-matching between the output on the 'Russound ADP 1.2'(s) and input of the 'R16'.

I'm not married to the 'Russound'(s), especially if they are mixing the (negatives wires). My choices are to buy two more...(so that I'm only using one-side of each) Or return them (which I can). Then switch to another variety. The Ultimate find would be 'Speaker-Line Level to XLR'. If a product could be found that converted directly to 'balanced'-XLR, then I wouldn't need to worry about the 'isolators' above. in theory?

[Sam Spoons]

I'd suggest starting again and buying an audio interface with sufficient inputs and outputs and use some software to decode the 5.1 signal and also maybe a loopback in the AI's control app or a DAW. It must be possible to do it in software* and I can't see you ever getting real high fidelity from the system you have.

Failing that, get a new 5,1 rig with active speakers and a decoder that outputs line level, then you can split the outputs and have the speakers and the recorder working simultaneously.

Or how about this to feed the Zoom (assuming you have SP/DIF optical outs from the receiver)?

[robertkjr3d]

I'd suggest starting again and buying an audio interface with sufficient inputs and outputs and use some software to decode the 5.1 signal and also maybe a loopback in the AI's control app or a DAW. It must be possible to do it in software* and I can't see you ever getting real high fidelity from the system you have.

Failing that, get a new 5,1 rig with active speakers and a decoder that outputs line level, then you can split the outputs and have the speakers and the recorder working simultaneously.

Or how about this to feed the Zoom (assuming you have SP/DIF optical outs from the receiver)?

I may be a hack/wanna-be electrician. But I'm no sloutch... on methods for this application. Your changing the subject to something way-off-base again. You cannot decode individual channels from a SP/DIF... assuming it even outputted the full channel array without yet another 'Receiver'. Getting a 'DTS/Dolby' decoders....if you do buy a so-called decoder, 99% will only output 2-ch, not 6. And they won't work with the latest encodings. Don't you think I already investigated this route?!!!

I've already made 'high-fidelity' recordings using this box method that are almost indistinguishable from the original source (after edits). (but they do have the pops and clicks) So no... i don't believe its impossible. This can work! It just needs some tweeks.

[Sam Spoons]

Fair enough

[Hugh Robjohns]

Late last night I tried putting old-radio-shack Ground-Loop Isolators (not sure if that is similar to these in some way). I did see the noise had stopped. However, the sound quality also dropped.

I suspect they are indeed isolation transformers. Not surprisingly, you get what you pay for, and cheap isolating transformers often introduce audible distortion and a lack of low end, especially when being driven harder than intended by too high a signal level.

Also I'm still getting the pops/clicks.

Lots of reasons for pop-clicks... mostly likely to do with the digital recording side of your signal path between the Zoom and computer... so you need to make sure that is a click-free setup before worrying about connecting the receiver as a source.

However, there are other possibilities, including interference from light switches or other electrical transients getting into the mass of unbalanced wiring in your switch box.

I am also trying to read-up on 'Impedance' and seeing if I was just totally mis-matching between the output on the 'Russound ADP 1.2'(s) and input of the 'R16'.

As long as you're feeding its unbalanced line inputs all should be fine.

The Ultimate find would be 'Speaker-Line Level to XLR'. If a product could be found that converted directly to 'balanced'-XLR, then I wouldn't need to worry about the 'isolators' above.

There are plenty of passive DI boxes that will accept a speaker level input and provide a balanced mic-level XLR output. For example, the ART PDB boxes -- available in single, dual and quad-channel versions -- have a 40dB input attenuator for speaker-level inputs. And the internal isolation transformers and ground lift switches will break the ground-loops too.

https://artproaudio.com/product-category/active-passive-dis/

[robertkjr3d]

There are plenty of passive DI boxes that will accept a speaker level input and provide a balanced mic-level XLR output. For example, the ART PDB boxes -- available in single, dual and quad-channel versions -- have a 40dB input attenuator for speaker-level inputs. And the internal isolation transformers and ground lift switches will break the ground-loops too.

https://artproaudio.com/product-category/active-passive-dis/

These passive-direct boxes... are am really interested in. So I need to wire my speaker connects to 1/4th... then into those hmm i love it. Sold man!
I looked at the dual-Arb-passive box. But I think like many dual(stereo) devices it mixes the negatives. I likely will need single-converter-boxes. But i gotta get-back- to work. lol

[Hugh Robjohns]

It would be worth checking with a multimeter to see if the speaker 'negatives' are all commoned at the power amp.

On most moderately sized power amps they are almost always all tied together and grounded.

On higher power amps, and where the outputs are being driven in a bi-amped or bridge fashion, the negative terminals will be powered by one amp module, and the positive terminal from another. In amps like that grounding the negative output by connecting it to another device could easily damage the amp... so it's definitely worth checking.

But I suspect in your case that all the negatives are actually joined together to a common ground in the amp, so there'd probably be little point in keeping them separate at the DI box.

[robertkjr3d]

It would be worth checking with a multimeter to see if the speaker 'negatives' are all commoned at the power amp.

On most moderately sized power amps they are almost always all tied together and grounded.

On higher power amps, and where the outputs are being driven in a bi-amped or bridge fashion, the negative terminals will be powered by one amp module, and the positive terminal from another. In amps like that grounding the negative output by connecting it to another device could easily damage the amp... so it's definitely worth checking.

But I suspect in your case that all the negatives are actually joined together to a common ground in the amp, so there'd probably be little point in keeping them separate at the DI box.

No they are not.... Most modern receivers are not generally built 'common-ground'
You would not mix the negative wire with the negative wire of the left & right channels. Or for that matter the 'Center'... (rear-left & rear-right)... or if you had any more channels.
Watch this: https://www.youtube.com/watch?v=Tonj3PhnCfw
Now if you had a plain old Guitar amp... it probably would be.
That guy explains not only what is common-ground, but also how floating-ground receivers work. I think that is what they are called.

Edit:... I'm completely wrong. Tested... again. See below when I apologize...