Kimber Kable REL-Cu subwoofer cable

[Shrinky Smurf]

I’ve been disappointed with the stock 10m Neutrik cable that came with my REL T-zero sub. It’s a great little sub for a medium/small room, and serves duty in my 2.1 home office setup. The cable originally came mis-wired, but I did not know. It took a lot of troubleshooting to find my initial hum was located at the Neutrik connector. Then it involved a lot of finicky fiddling to get it in the correct position, with the cord laying in the perfect position so the sub would fire but not hum. Eventually I got fed up enough to take the connector apart. There were three wires, and four Phillips head tiny screw clamp connectors for the tinned ends of the wires. I immediately saw it. Wow, that’s the culprit! Loose wiring, especially the yellow wire. There were four possible locations for the wires, and the three wires. I double checked their locations. The yellow wire was almost dangling loose in the wrong place. Flopping around in there. I corrected the wiring, and made sure the connections were snug. I fired up my system, and lo and behold she worked beautifully. I really love this little sub, but I just didn’t trust the cable. The amp ends were still bare wire... like thin, tiny, little brittle hairs at that. That’s how they come, and I was undecided on the cable, so did not want to invest too much in finishing it. Plus, that 10m length... I had to wind up the extra and tuck it away out of sight because I was not committed to paring it down to match my run. Who knows what was going on electromagnetically with that rats nest. All in all, it was just feeling adequate to me. What’s a guy to do?

Find a new cable!

Well, I searched. REL makes an upgrade cable. The few reviews out there are positive. It may be good, but I had lost trust in their stock cable. There are a handful of people custom making REL sub cables online, and some looked good, while others looked sketchy. That seemed like a crapshoot to me. Few major manufacturers advertise them prominently if they even make them. Kimber Kable makes an REL-Cu sub cable that can be found in 2m, 3m, and 4m lengths. My one reservation is there is a tiny bit of DIY involved. They make an Ag cable too, but I could not find it anywhere. I really enjoy my Kimber 8TC speaker cable, and I asked someone I trust, and they recommended going with the Kimber. For my run, 3-4m was best, so I went with 4m.

Well, it arrived. The quality was immediately noticeable. The first thing I inspected was the Neutrik end - my previous problem spot. The Neutrik connector was much more solid and robust that the stock connector, inspiring confidence. The Neutrik is on one end, and each set of wires (black, red, and yellow) comes in a pair that are individually wound as a pair that runs the length of the cable. Definitely heavier gauge than the wimpy, limp single wires that come with stock cable. They are nestled in a protective black mesh that seems durable. On the amp end each of the three pairs of wires come in loose ends, twisted together by color. Kimber sends a small packet which includes three loose spade terminals, three loose banana terminals, three heat shrink sections (red, black and yellow), and two small sections of mystery solder. No explanations. No instructions.

I probably last soldered in any serious amount back undergrad over 20 years ago in many of my long-forgotten EE classes, and maybe once about 7 or 8 tears back to repair an antique lamp inherited as an heirloom, so I am not totally inexperienced, but it’s been a while. I still have my old solder gun (yes, I am a pack rat), and it still works, but the tip is badly oxidized. Not sure about the temp. So, I get a new iron. I wanted to do this right. So, I ordered some Cardas silver solder, and Cardas flux to ensure the best connection. I have no idea what solder they sent with the cables, and it is probably excellent, but I am just that obsessive about some things. I decide on spades for a tight connection, but the amp posts are somewhat crowded, so I take some channel locks and bend them to 30-45 degrees before soldering so they will fit with the speaker wire spades. It worked very well and no need to buy special angled spades. I did this prior to soldering because I did not want to compromise the mechanical integrity of the solder connection if done after. One at a time, I place the heat shrink tubing on, carefully tinned and soldered each pair to the respective spade, slid the tubing down to the end and shrank it with the heat gun. Looked nice and sturdy. If I were an electron, I would want to ride right the rough that connection! Now for the test.

What were my expectations? Really, I thought this would be more of a cosmetic upgrade than anything. The sub is separately powered, and as long as the signal was being transmitted accurately to the little T-zero, I thought that separate power should take care of the rest. Bass is bass. How good can bass get, any ways, I thought. One reason there are no pics here is because I didn’t think it would be noteworthy. I prepared my system for A to B testing, just to satisfy my curiosity. When would I do this again?

My reference albums for bass evaluation are Gorillaz Demon Days and the Tron soundtrack. I stuck wit Gorillaz for this one.

The stock cable sounded really good. What a nice little sub, I was thinking to myself. Did I just waste all this money on snake oil?

So I turned the system off and carefully replaced the cable. The Kimber spades are large, and the Cambridge posts must be standard, and I had to hold them in place while hand tightening the posts or they’d try to squirm out. I felt confident in a secure connection. Replaced everything and fired it up again for another listen to some well-known tracks.

I was dumbfounded. Wow! I was not expecting this. So, the volume was up, was this just a mind trick with tighter connections? Now I knew the difference in bass people talk about is real. The signal was much clearer to the little T-zero. The bass was not only hitting harder, but the notes were crisper, with an audibly quicker decay. Bass was not as muddy... more defined. Nice! Another surprising find... one that was unexpected, and I cannot explain - my little monitors even sounded better. Say what,?Perhaps my ears are deceiving me, as this makes no rational sense. Yes, I was hearing things in the lower mid-range particularly better. Even picking out things I had not heard before. I trust my ears. The connections must have been made more solid, with better integration in some way. I am not sure exactly how the Neutrik REL connector works, and if it is just passively receiving signal from the amp, or how it may actively be involved in the circuit. Perhaps it is placebo, but I’ll take this placebo!

My wife, who could care less about audio, happened to be in the room. She stopped what she was doing and spontaneously commented how much better it sounded, and even started hopping to the same music she was ignoring before. “What did you do?” she asked. I began to explain and she quickly lost interest...

For anyone interested, the Kimber Kable REL-Cu subwoofer cable, was an outstanding upgrade in my little system.

Once I get my new monitors I will have to re-evaluate. I had been considering making it a 2.2 channel system, but I may not need to. Perhaps the weakness I was sensing was in the connection, and not the sub. If I do go 2.2, unfortunately the run to the second sub will be longer than 4m, and I will be back on the hunt for a solid REL cable.... and options seem to be limited.

Best,
Shrinky

[Poppyhome]

Thanks for your interesting adventure with the REL Neutrik Cable.

As a previous owner of a few REL subs a number of years ago, I am somewhat familiar with the Neutrik cable. I find it disturbing that for most of REL's history they maintained their stock cable was more than sufficient for its needs. This thinking only changed a few years ago.

A particular cable must be manufactured correctly and with enough quality and specifications for its specific needs. It does not need to be made of exotic materials or be expensive. Some people disagree.

I liked Signal Cable mainly because it looked nicer, will make you any size or configuration, and had terminal end options, but I never noticed a real difference in performance compared to the stock cable. Just my opinion and don't want this to be a cable war.

Ron

[Shrinky Smurf]

Thanks, Ron. I was just sharing my experience as well, hoping it may help someone, as there is not a lot out there on this. REL makes outstanding products, and the company does say their stock cable should be good enough. Though, they offer an upgrade themselves. I wish I had a better experience with the stock cable, and I would have shortened it to length and used it. I appreciate the feedback, and don't want a cable war either. That was not my intention. My experience so far has been that quality cables do make a difference, though to what extent exactly I cannot fully say. As I stated, I really don't have a dog in the fight, and was not expecting a difference. The differences I heard may have been related to more solid connections on both ends of the new cable. Who knows? That is why I shared the whole story. Perhaps there is something else I am missing. I am open. Thanks again!
Shrinky

[clpetersen]

I have a pair of REL T7i's in our media room and very happy with them.
I had them set up two ways - in the back corners and now in the front corners. Both worked well with some attention to trim, phasing etc.

Cables: To run them in the back, I needed more than the stock ten meters (running under floor around perimeter of room). Called (emailed) REL and they were helpful. Built my own, using standard speakON parts and 14 gauge Belden twisted pair (unshielded). 14 gauge is complete overkill, but added little to the overall cost (since running in stereo pair, needed only two wires per sub, and jumped inside the Speakon end)
REL stock cable is basic but adequate (excepting assembly errors). It takes the voltage from the very low output impedance amplifier speaker terminals (typically < 0.1 ohms) and delivers to the high impedance (150 kilo-ohm) REL inputs. Meaning it carries almost no current and is effectively shorted at the speaker ends, making it largely immune to noise pick-up (e.g. 60 Hz hum, etc.). Smart.

So, in this particular case, a well assembled, good quality but straightforward cable will be all that is required.

(in the front corners, I use the original REL cable, shortened (cut) to 4 meters).

For anyone else contemplating a customized REL cable.

[Poppyhome]

Originally Posted by clpetersen

I have a pair of REL T7i's in our media room and very happy with them.
I had them set up two ways - in the back corners and now in the front corners. Both worked well with some attention to trim, phasing etc.

Cables: To run them in the back, I needed more than the stock ten meters (running under floor around perimeter of room). Called (emailed) REL and they were helpful. Built my own, using standard speakON parts and 14 gauge Belden twisted pair (unshielded). 14 gauge is complete overkill, but added little to the overall cost (since running in stereo pair, needed only two wires per sub, and jumped inside the Speakon end)
REL stock cable is basic but adequate (excepting assembly errors). It takes the voltage from the very low output impedance amplifier speaker terminals (typically < 0.1 ohms) and delivers to the high impedance (150 kilo-ohm) REL inputs. Meaning it carries almost no current and is effectively shorted at the speaker ends, making it largely immune to noise pick-up (e.g. 60 Hz hum, etc.). Smart.

So, in this particular case, a well assembled, good quality but straightforward cable will be all that is required.

(in the front corners, I use the original REL cable, shortened (cut) to 4 meters).

For anyone else contemplating a customized REL cable.

Thanks for sharing...........................if I ever go back to REL I will also consider building my own, especially since I had success building my own speaker wires.



Ron