RCA splitter

My use is temporary, for comparisons primarily.

For Stereo you need two splitters.

Pair of Jacks on a Device may be too close together for splitter gizmo, while splitter cables preserves tight spacing on the unit (i.e. my Vintage McIntosh Preamp)

Length of splitter cable can move 'joint' up for easy access

This stereo kit is available to buy by the foot

https://www.amazon.com/ROCKRIX-Female-Speaker-Adapter-Splitter/dp/B08PKS42P6/ref=asc_df_B08PKS42P6/?tag=hyprod-20&linkCode=df0&hvadid=475825775681&hvpos=&hvnetw=g&hvrand=18138763782454415975&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9003526&hvtargid=pla-1163174276384&th=1

.........................................

i.e. I temporarily hook up friend's equipment (or my other stuff) to my system by adding the splitter 'down/back there', then a pair of jacks at accessible height.

Permanent/semi-permanent split, then access less important.

................................................

You might need 'two in' and/or 'two out' depending on what you are doing

Balanced splitter, gives you locking connectors, and you choose your lengths for positioning.

https://emotiva.com/products/xbal-1x2?utm_source=google&utm_medium=cpc&utm_campaign=20042245837&utm_content=656394514266&utm_keyword=&gclid=Cj0KCQjwldKmBhCCARIsAP-0rfzAVygLkxXOubiyMyRdSxJH_tWDWfjeHkAq3ELkWv88fJgsd0va648aArnpEALw_wcB

Your chosen splitter, consider supporting the weight of the two cables to minimize downward force on the male end into the units female jack.

you can make your own to use locking connector to hold the weight and avoid possible poor connection

https://www.amazon.com/Parts-Express-Locking-Connector-Solder/dp/B0002KR26I

mulveling

"However, physical contact connections in the audio chain can be very tricky. If you have a single bad contact, it can very easily cause problems like (say) L/R channel imbalances."

so true. the basis of my comments to OP

1. I changed all my RCA cables to Locking RCA jacks

2. If Balanced option available, even for short residential use (normally balanced not needed unless long runs), I use the balanced because they are locking connectors

3. my vintage McIntosh mx100z had slightly small diameter, and corroded rca jacks, Audio Classics replaced all the RCA Jacks with new gold plated ones, hooray!