Speaker cable Experiment - Do you know the difference in Copper Cable Material Quality in Coax cable vs run of the mill House Wiring?

[Deaf Cat]

Hi

I was adding bracing to my main stereo speaker cabinets over the weekend and thought while they were apart I could replace the internal speaker wiring...

 

During the bracing process I turned up the kitchen stereo, Squeezebox->Adcom GFA power amp->Rega R1's,

From amp to speakers, 1.5mm2 solid core copper cable for house lighting circuits (what was handy at the time) guessing pvc jacket.

After an hour or so I had to turn it off, the bass was nice and tight but the top end was far too edgy, thin and scritchy, agony after an hour or so.

 

Re-wired with some Cavel QF100 satilite low loss cable, 1mm2 solid core, polyethersomething foam dielectric, full copper foil and then braid and pvc outer jacket. (center core cable conductor only, shielding not connected to in any way)

Rounder fuller bass, top end now smooth, after an hour or so, head still nodding, foot tapping, :-)

 

So, what about 2.5mm2 house wiring I thought, could do with a little more clarity up top. Re-wired and got back the thinner sharper top end, and bass was tight once again, sound seemed bigger more powerful than with the 1.5mm2.

However foot stopped tapping, head stopped nodding, and did not take long for the scritchy top end to get to me once again.

 

Cut 4 more lengths of QF100 and rewired 2 x 1mm2 coax to each plus speaker terminal and 2 x 1mm2 coax from each negative speaker terminal. No shielding connected, just the center conductor used for signal transfer.

Top end not so clear as the 2.5, but nice and smooth, bass full and still pretty tight, actually now noticed I was missing mid range before, now a nice balanced sound, I was sucked into the music and foot tapping was back, but top end clarity gone...

The twin runs of coax are staying in the kitchen system, as lovely to listen too :-) , even if it lacks clarity...

 

So my questions being:

 

1 - Are there different qualities of copper used in the different types of cable?

 

2- If the coppers are the same quality dielectric may cause a noticable effect...?

 

3- Would the plain house hold cable have have capacitance differences to the coax cable due to the coax's shielding, would this cause a speed up or slow down of some frequencies?

 

4- Would it be daft to consider running a 2.5mm house wire in parallel with the 2x1mm coax, to maybe achieve a bit of clarity with a bit of smoothness... or resistances of different cables would cause a smeering of the sound as the signal would arrive at slightly differnt times?

 

Too many questions popping into my head... time for a little lay down, too much brain power used trying to understand something my wife could not care less about ;-) Supprised I have not heard "are you putting the kettle on? Or "What's all these extra wires in my kitchen" :-D

 

Cheers for any thoughts!

DC

[robocop]

So my questions being:

 

1 - Are there different qualities of copper used in the different types of cable?

 

YES definitely, typical industrial/ house wire is not pure copper but has impurities contained in it. So called hifi cables now have very pure copper with almost all impurities removed and have tech sheets saying this 99.99999% copper. It costs more to produce pure copper hence price differences although this is not a reason to charge huge prices as is the case with a lot of these cables.

 

2- If the coppers are the same quality dielectric may cause a noticable effect...?

 

Copper is a conductor and YES it may but is only one factor in the sound, Dielectric(insulation) is another, cable construction(how its all put together in a cable). All these make for the reason cables sound different to each other.

 

3- Would the plain house hold cable have have capacitance differences to the coax cable due to the coax's shielding, would this cause a speed up or slow down of some frequencies?

 

Don't even compare both do very different jobs. House cable only has one job to deliver the required voltage/current to a device to make it function correctly(toaster, heater, lights). Coax is much more delicate dealing with low voltage/currents hence more critical shielding etc.

 

4- Would it be daft to consider running a 2.5mm house wire in parallel with the 2x1mm coax, to maybe achieve a bit of clarity with a bit of smoothness... or resistances of different cables would cause a smeering of the sound as the signal would arrive at slightly differnt times?

 

Definitely never use house wire in any critical signal paths(USB, digital, interconnects, speaker) on a Hi-Fi.

 

Certainly rewire your power supply circuits to Hi-Fi with 2.5 mm or bigger. I've done this and what a sound improvement. I completed two circuits one for digital and one for analogue. This cable is directional and should be checked before installation. Nothing else runs on these circuits.

 

HiFi Cables are getting to a high standard nowadays, take the USB cable, the latest best being the Lightspeed, unequivocally voted by all who hear it as the best they have heard. The manufacturer has gone to huge trouble to perfect this cable when you read the web site overview. And in this light is probably justified to charge what he does. It has only recently been recognised that even USB cables make a difference. All cables/wires make a difference including the ones inside your hi-fi components(most of which are industrial/house grade and not hi grade copper). I'm talking about transformers, capacitors, point to point wiring etc.

 

Robert

[mayhem13]

Gotta love this place!

[sandyk]

Gotta love this place!

 

Even so, I bet you use so called OFC cable for your speaker leads and internal speaker wiring etc. ?

[iago]

2- If the coppers are the same quality dielectric may cause a noticable effect...?

 

It's related to dielectric and geometry. Each cable has some unique electrical parameters which interact with source and sink impedance to form a bandpass. The theory behind it is complex but can be approximated by treating the transmission line as a lumped circuit (two port network) consisting of specific conductance, resistance, capacitance and inductance of the cable. All four parameters are influenced by geometry (wiring material, diameter, spacing, twisting) and dielectric.

 

Have you seen the various constructions TNT created over time? Your satellite cable was also covered. A very promising material for DIY experiments, I believe, is CAT-5 network cable (also found on the TNT web site).

[YashN]

Nice of you to experiment and share, Deaf Cat! Been doing the same for a while and more recently with cables.

 

I started with speaker cables and did a simple 3-pair braid with Cat-5 Ethernet for each speaker. Great results.

 

Spurred on, I then decided to emulate the LightSpeed and the iFi Gemini USB Cables and here I totally expected to botch an existing USB cable I used as a base for experimentation. My goal was to separate the Signal and Power lines. For the pair I removed out of the initial double shield, I used a Satellite cable shield and aluminium foil. Even with somewhat dire craftsmanship, the results were fantastic. Flabbergasted.

 

Next, I thought of trying my newly-found hobby with a DIY power cord. Since I liked whatever the shielding was doing in the previous cable, I built a special cord for my amp, reusing the plain Satellite coax as is this time. My amp only takes two prongs, so I built what you can see as Flavour #3 on Chris VenHaus's page, except in my case I just twisted the two satellite cables, then connected their shields together, then screwed that into the 3-prong plug going into the mains outlet. I wasn't expecting much here since for power, I believe thicker gauge should be better. Initially, I noticed less treble, and wasn't sure I liked the result. However, on the next day, when I demo'd the two cables, we preferred the DIY one: it has a fuller range, whereas the stock power cord made the overall sound thin in comparison, although with more treble. Very positive results for very little time and material invested. I am listening to all these cables as I write this.

 

Yesterday, I did my own interconnects, shorter than the usual ones and using the satellite coax again. There was more treble with those again, but I haven't spent much time with them as I don't like the lack of solid construction of it, but I will delve into that again for sure.

 

All this to come back to the speaker cables: now that I know my Cat-5 is unshielded, I am tempted to adding this against EMI/RFI and perhaps connect it to the amp chassis or something like that.

 

One thing you could try with the satellite cores is to twist them as in the Cat-5 braided construction (each + - pair is twisted separately, and then you twist those two resulting cables also but some people say in the other direction here). Of course, you make sure + is connected to other + at the ends and same for -.

 

And Robert, I totally agree, you can count me as a believer now, everything has an effect. To be sure, I had to do it myself, but now there's no room for doubts, even for USB cables.

[tranz]

Thanks for sharing.

 

Having pulled apart a variety of speaker, USB, LAN, power cables it is not surprising the amount of different results. So many different gauges, metal types, twisting frequency, no twisting, quality of attachment and shield types. Even within the supposedly same LAN types I saw a variety.

 

Logically, whether it is a power, USB, LAN, hdmi, etc. cable, there are a few key things that will impact the signal:

 

- conductivity i.e. metal type

- shielding (metal type, braid, foil, both)

- gauge

- twist tightness

- quality of wire to connector attachment (metal type of connector, method of attachment ultrasonic welding/solder type and quality/crimp etc.)

- dielectric material

 

None of it is magic, and it certainly does not have to cost a crazy amount.

 

But when you realize how much time it takes to do DIY well, forget about having e.g. an ultrasonic welder inhouse, it is not that strange to see why a good powercord can cost $100.

 

For speaker cables I have had good results with bluejeanscable. Simple, no-nonsense and a time-saver.

[pooger]

With few exceptions (cartridge to head amp is vdh monocrystal silver and head amp to preamp is Lindsay Geyer, which is a very stiff mu metal) I've replaced all my wiring with DIY. All solid core, gauges from 26 to 18. The most basic are navy surplus silver plated copper with Teflon, (I bought spools of this many years ago to use as hook up wire), some are soft annealed silver with silk, at this point most are either neutrik XLR (where I braid the wires) or very lightweight phono plugs (with wires twisted). Most have no shield beyond twisting or braiding. Cables are one of the easier DIY projects, and the results can be pretty competitive with top tier products.

[RealAudio]

So, tell me why you're using coax as speaker cable as opposed to a 10 awg Belden 5000?

[bluesman]

Having pulled apart a variety of speaker, USB, LAN, power cables it is not surprising the amount of different results.

That's for sure - but there are so many variants that it's hard (if not impossible) to know what to expect from most of them. I've been amazed and often disappointed at what appears to be very flimsy internal wiring in speaker systems. I was triamped for about 15 years in the '70s and '80s (Nakamichi electronic crossover for rewired LS3/5As driven by a Marantz 8b and a Citation II or a Hafler 500 plus a Yamaha NSW1 powered sub). I've always wondered if the improvement in sound was more from elimination of all that cheap, tinny, tiny wiring than it was from ad hoc amplification of different frequency ranges. After all, I stuck yet another processor in the circuit (the electronic Xover) with another noisy power supply plus three more sets of line-level interconnects. Yet the improvement in sound was obvious, and it had to be at least partly from elimination of the wiring and crossovers in the speakers. Even when I multi-amped the Infinity Reference Standard IIs (that I loved until my wife finally couldn't stand speakers as big as she was in our living space any more), the SQ improved - and they were wired pretty well inside.

 

I've not heard a difference in SQ associated with power cables in my own system. My Prima Luna amp came with a serious cable, as did my Emotiva stuff. And I have 2 plug molds on the wall behind my system, each on a dedicated 20 amp circuit off a 400 amp board (with similarly separated 110 and 220 circuits for every noisy device in the house from refrigerator to heat pump, plus a 100 amp subpanel in the garage). So there may not be as much to gain in my house as would be the case in an apartment or a house with 150 amp service and more lines on fewer breakers.

 

When we move to a retirement apartment in a few years, I'll probably have to invest in serious wiring and power conditioning to retain much of the SQ I have now.

[Deaf Cat]

Cheers Robert for your nice reply makes sense!

 

I would therefore guess the coax copper cable is of a better quality than the mains, as it has a small(ish) signal to keep in check. Will have to see what burn in brings.

 

Thanks Iago, I understand now, this is why I spent 6 months listening to cables from my 3 most local stereo shops and did not find one that did ALL that I wanted, very complex and so so many variables! Thanks for pointing that out.

 

I did read TNT speaker cable with coax but did not think that using the –ve shield as an additional +ve conductor would yield good results, foil and solid core would vary so much in resistance and maybe blur the signal – but then what do I know, I’m learning, and will have to try it at some point!

 

Oh YashN I was trying to keep to speaker cables, but you have me interested in experimenting with mains as well now. I did make up a IC out of the QF100 a while ago and it was not bad, must say, treble was enhanced, unlike when used as speaker cable… Strange… Maybe I need to experiment and connect the shielding on the speaker cable, cheers for sharing.

 

Thanks tranz and pooger for your comments, interesting reading.

 

RealAudio, in answer to your question, I had coax, and mains cable in the shed, thought they were both pretty similar with solid core copper conductors, so was expecting them to sound pretty similar, so experimented and found otherwise and wondered why.

 

Cheers Bluesman for your comments, once the internal speaker cables are sorted then mains is next on the list to experiment with :-) The cables in my speakers are pretty chunky I’d guess at 1.5 – 2.0mm csa, stranded, however, the almost bell wire that goes from the binding posts to the crossover is somewhat disappointing, This will go soon as a couple of active boards should arrive soon, I hope.

 

Thanks all for your comments :-)

Cheers

DC

[beanbag]

How long were these cables?

[Deaf Cat]

How long were these cables?

 

approx 1m