Pairing Lyngdorf 2170 with REL T9x

Playing around with it this morning I found an interesting pattern. When I hook it up as REL suggests, with their cable, the popping and hum varies with with what device is turned on or off first.

If I turn the REL on without the Lyngdorf on, I get the hum that can be adjusted with the hi/low and crossover controls on the REL.
No pop when the rel gets turned on alone.

With the REL on, I turn on the Lyng - that creates a pop but eliminates the hum and the sub seems to work.

But when I turn on the Lyng first, and then the REL, no pop and works.


Turning off the Lyngdorf when the REL is on, results in the pop.
But if I turn off the REL first and then the Lyngdorf, no pop.

So - to avoid the hum and pop, I have to turn the Lyngdorf on first, then the REL. And when shutting down, the REL first and then the Lyngdorf.

Not sure what it means.

PC = Power Cables
IC = Inner connects (RCAs, XLRs and Speaker cables)

They shouldn't be all jumbled together.. put some space between them and cross at 90 with 1" of space.. Like magic for noise reduction..

Start fresh, make sure Everything is plugged in all the way. Run chassis grounds.. Clips with wires will work for a test. Ground the chassis.

Yup. I tried it with a few different RCA on different output plugs on the amp that weren't being used. 
It shouldn't be this hard which makes me think of user error. I'm going to take a fresh look tomorrow - or at least I hope to.
Thanks for your help

You need to follow step 2

 

Next, connect a long RCA-RCA interconnect from either an unused input on a preamp or receiver to the REL’s .1/LFE input. Do this even if you have no interest in theater, you are creating an audio ground, nothing more. This is true for 2-channel systems, we are not using the .1 LFE input for anything more than to produce ground.

https://rel.net/blog/2017-12-27/how-to/connect-rel-class-d-gear/
I'm not running class d but I found this to be a necessary step for me.

I did try a few different RCAs. All on same circuit but not sure what the amps are. 
Right now, there is a bit of a jumble but not too bad. PC and ICs? Sorry, not sure what those are.

It's strange (at least for me who doesn't understand this stuff) that the amp manufacturer has one way to install a sub and the subwoofer manufacturer has another... 
Thanks again for your ideas. 

You hooked up a good RCA too? You tried a few different ones? Noise is usually a voltage difference, between the two components.. Completing the ground through a GOOD RCA might help.. OR running grounds via chassis to chassis..

Is everything on the same circuit? or are they on different circuits? Same 15 or 20 amp is best..

PC and ICs are routed with space between them. Not a jumble of wires??

Just asking a few quickies..

Thanks for your help. I really appreciate it. Yes, that looks like my manual, but it seems like things are a little different with D amps

https://rel.net/blog/2017-12-27/how-to/connect-rel-class-d-gear/

I'm using this solely for music - no tv involved. I've contacted REL and they're reaching out to Lyngdorf. Just figured there had to be someone who has REL and Lyngdorf who has figured this out...

https://rel.net/wp-content/uploads/2021/04/REL_Tx_Manual_12-20_11_WEB.pdf

I guess this is the manual?

Page 12

The Serie T/x models have three separate inputs. A high-level input socket, a .1/LFE RCA input, and a low-level RCA input. This is to facilitate use with both two-channel stereo systems and AV surround sound systems.


Page 20 for high level connections. (see pictures in manual)

Connect each sub to the speaker terminal outputs based on the following diagrams for standard stereo amp, non-balanced mono blocks or balanced differential mono blocks.

Where does it say to hook to chassis? Nothing is floating...



From the Amp manual

4.6.5 Output enable
Enables and disables HDMI audio output to the TV. This feature is only available if the digital output connector is not
in use.
When enabled, this feature will send the current digital audio signal though the HDMI cable to the TV. Disable if you
want the TDAI-2170 to send the current audio signal to the digital output connector on the back.

Hope this helps.

Regards