Cdc, this is a highly system-dependent decision.If it were just simple resistance, or just skin-effect, the decision would be simple. But the capacitance and inductance of the cables interact with the characteristics of your components and speakers. This is why different people swear by very different cables as being the best. They may be the best, but maybe only on their system. If you are doing DIY, it may be of benefit to try some low-inductance configurations and some high-inductance ones. Also, do the same with capacitance. When you hear the difference between these designs, you can determine which way to move toward your final design. It is much easier to do this with DIY, than to buy 25 different cables to test and see which ones you like. From my experience on interconnects, if you don't have RF problems, stay away from shielding. Sound is better without it. With speaker wires, bare wire terminations are generally better than using termination lugs. I use 30ga solid-core copper wire with no shield for my 1 meter interconnects, and 22ga solid-core copper wire for the 3 meter speaker cables. Single conductor run for each. No twists, braids or anything. I keep them well separated along the entire runs. Teflon tube insulators. I use tube gear, and it is quite fine sounding. |
CDC: Pick up a spool of solid core copper magnet wire @ Radio Shack ($3.99). The spool contains three gauges (30, 26 and either 24 or 22, I forget). Try the two larger gauges (26 and the other one) in single runs (do not twist them). Twisting is for larger gauge wire (from my personal experience) and completely ruins the sound of 24 gauge, on up, solid core wire when it is used as speaker cable (this is assuming that the cables will not exceed 8'-10' in length).
You can remove the lacquer (@ the ends) with 600 sandpaper, or better yet burnishing cloth. If you like the sound then high quality magnet wire is available for very little money (Michael Percy @ percyaudio.com carries it).
I have been using 26 gauge solid core copper/Teflon speaker cable (single runs) for a year and a half in my main rig and have used the magnet wire (also ended up with 26 gauge for the balance that I like) in bedroom systems.
Never tried 22 gauge, but 22-26 gauge seems like a reasonable span to experiment with.
The sonic benefits of such simple designs (smaller gauge and single runs w/o spades, etc.) are reduced smearing and a much more open sound (the sound is more in the room than obviously coming from the speakers).
Imaging on the otherhand is not as precise as some of the more complex designs (I find slightly fuzzy imaging to sound more realistic), but do not confuse my description of the imaging with fuzzy overall sound as the detail of these simple designs can be quite startling (my description is lacking, not the sound:-).
The sound, during break in, of these small gauge/simple cables can be very, very, very odd, but from my experience it only takes 50-100 hours for them to stabilize. For more info on this run a search of "OTA" and read the thread about the 47 Labs OTA cable (it is 26 gauge solid core wire used in single runs).
Anyway, it should be a fun project for under $5 and if you like the sound then you may be able to make very nice DIY cables (both IC's and speaker) for your entire system for very little money, if you stick with copper instead of silver wire.
I would not worry about the the small gauge in regard to amp power as I once used 26 gauge with a Musical Fidelity X-A1 amp (50 watts) and others have used considerably more power than this with like cable (again take a look @ the OTA thread which contains a great deal of info on the matter). |
Thanks for the help and link. I can get 600 ft) 18 gauge magnet wire for $15.45 from www.mcmaster.com. The 26 gauge is $15.52 for 3,000 ft.
Teflon tubing is .14/ft for .034 I.D. (AWG 22 is .028") and .09/ft for .022" I.D. (AWG 26 is .018"). So it will be a slightly loose fit. I guess this is okay.
I have heard wires should not be allowed to vibrate hence the heat shrink tube idea but if it's just a single run of wire then just sliding it through the teflon should be okay I hope. |
CDC, if you don't have some room in the tubing you will never get the wire through it. You will be very frustrated with the trouble you are going to have as it is. Do not "kink" the wire by pushing too hard on it. If you do, the kink will make it even harder to push the wire through from that point on. The best way I found is to stretch out the tubing totally straight, and clamp the end, so there are no bends or curls. Then carefully push the wire through. When you get to the end, then unclamp the tip of the tubing and push the last inch of wire through it, or cut last bit of the tubing off and grab the tip of the wire with a needle nose plier. It's not as easy as you think. Definitely straighten out the tubing and hold it straight! |
CDC: 18 gauge may involve using a more complex design in order to get it to sound good (it will also never sound like, or as realistic, IMO, as the smaller gauge wire, when used as speaker cable, which is what I was attempting to coax you to try:-).
TWL is "right on" about feeding wire through Teflon tubing (it is not an easy task).
Yes, vibration is a concern when using oversized tubing in longer runs, but such tubing is not required with magnet wire. Magnet wire is coated with lacquer which serves the same purpose as the Teflon tubing and which also has similar (favorable) dialectic characteristics.
The best insulation is "air" and what I try to achieve in cable design is the next best thing (@ a reasonable cost) which is either lacquer or Teflon.
The good thing about the RS spool of magnet wire is that you get two useable gauges to experiment with (in regard to speaker cable), plus the 30 gauge can make decent IC's. The M-C wire may be of the same quality as the RS stuff (which is not HQ cable), but you don't need nearly that much, plus you should be experimenting with various gauges. Once the gauge is determined, then purchase high quality magnet wire from a source such as Michael Percy. HQ magnet wire (with a boutique "name") can run as much as $8/ft from other sources, but Percy (and I assume other sources as well) carry HQ oxygen free magnet wire for "much" less than $1/ft in the 22-26 gauge range.
End of rant. |
Dekay, the magnet wire I found has a clear enamel coating. So you're saying I don't need ANY tubing to protection it?
* Would this wire configuration have any funky inductance or capacitance like the Goertz stuff? Probably not, but I want to make sure.
* Should I separate the runs by 1/4" or more? Or can the 4 bi-wire runs be bundled together?
* I found the Radio Shack wire. It too is enamel-covered copper and has 40 ft) 22 Ga / 75 ft) 26 Ga / 200 ft) 30 Ga. Not sure about enamel vs. lacquer coating.
I guess it couldn't hurt to try thinner stuff. I am bi-wiring and could do 26 for the top and 22 gauge on the bottom.
Southwire (800) 444-3600 sells round, rectangular, and square magnet wire with nomex, kapton, or paper insulation. MWS (888) 697-9473 sells MULTIFILAR parallel bonded magnet wire said to offer consistent capacitance and impedance. Phelps Dodge Magnet Wire co sells coaings to apply to magnet wire. I couldn't find Michael Percy.
Going to http://www.sundial.net/~rogerr/wire.htm they recommend:
Wire Size 2 ohm 4 ohm 6 ohm
22 ga 3 ft max 6 ft max 9 ft max
20 ga 5 ft max 10 ft max 15 ft max
18 ga 8 ft max 15 ft max 23 ft max
This site also says when resistance gets too high it makes the amplifier look like a current source. "This means the speaker frequency response will tend to follow the rise and fall of the speaker's impedance curve. The impedance of most speakers is not constant with frequency". This could cause frequency response inconsistencies.
So since my speakers are 4 ohm and the run is 12 feet I felt safe with 18 ga. However since I'm bi-wiring I guess the 22 ga may work.
==>I don't want to burn the house down from overheating some micro-thin copper wire! <== Hence the thought on using teflon tubing.
If people have been using 26 ga with50 watts or more, I would wonder how long a run they had. |
Cdc, I used the 22ga radio shack magnet wire on my 3 meter speaker runs. You can go without the tubing because of the protective enamel, but the enamel can get rubbed off and there is a small chance of shorting the wires together. For this reason I used tubing on mine. I also separated the runs by 2 1/2" all the way. With single-conductor runs, capacitance is really not an issue. With wires separated beyond the distance where the fields can interact, inductance is not an issue. I used 3/8" tubing around my wires in order to get mostly air-dielectric, except for the few small contact areas where the wire occasionally touches the tubing. In this case, even the dielectric is not an issue. The tubing provides a sound-wave barrier for the wire, so it will get less vibration, than if it was bare. Since the wire hardly touches the tubing, the tranferred vibration is minimal.
You will not heat up the speaker wires or damage anything. The tables you looked at are about 1% loss tables, and they really bear no relevence to this discussion, where the cable length is under 4 meters. The resistance difference at 4 meters is negligable. There is no risk of damage or fire with this type of wire and a 50 watt amp. |
Twisting is usually a better performer because it locates the forwards and return wires in close proximity and creates some field cancellation. When the forward and return paths are in parallel or twisted, this lowers the inductance substantially over separated wires. Braiding is really only for convenience to hold multiple pairs together. Braiding actually degrades the performance. If you select a braid that mostly makes the pairs orthogonal to each other, this will help. I would recommend using enough twisted-pairs to equal 10-12 gauge. |
(Thanks TWL)
CDC: TWL pretty much covers it. Also I like and will try his "big" tubing idea on the magnet wire that I have when I set up the second system.
Yes, the thin coating on magnet wire can become compromised (I always kept +/- separated with cotton ties/ribbon placed @ various places along the path), but again will try "big" tubing next time as it's more a sure thing (plus to see if it sounds better due to added damping).
TWL: Are you using clear inexpensive Lab tubing (the kind also used on ice makers in refrigerators), or is it Teflon tubing? Just curious as I have a bunch of the Lab stuff (used it for bare wire IC's once). Fry's has Teflon tubing now (and it is also not too expensive).
CDC: If you also end up trying the 18 gauge magnet wire then by all means experiment with Audioengr's recipe. When we (TWL & myself) recommend not twisting/braiding, this is in regard to the smaller gauge wire (not larger gauge solid core wire, such as 18 gauge).
Again, don't worry about the smaller gauges as long as the runs do not exceed 12' (8'-12' is the best range, IMO, for the smaller gauge wire based on trial and error).
As far as your BI-wirable speakers go, yes try 22/bottom and 26/top. Other options are running a single gauge through the bottom binding posts and then on up to the top posts all in one piece (you will have to strip the sections that make contact with the bottom posts, a well as the ends). If your speakers are out of warranty you could remove the internal leads from the top posts and attach them to the bottom posts (the speakers are no longer BI-wirable, but you have eliminated a set of binding posts in the signal path).
You could also try the "twisted" 18 gauge (two ply should be fine) on the bottom and then run a "short" single wire "jumper" (22-26 gauge) from the bottom posts to the top ones. I would not combine a single 12' run of the smaller wire on the top with a run of the twisted 18 gauge on the bottom as these cables will have very different voices and will sound odd. A short jumper (3"-6") however does not have this effect (guess such a short run does not have much character @ all:-) as I have tried this with braided Kimber Kable (on the bottom) and short 26 gauge jumpers running to the top (sounded good on a pair of Castle Isis speakers).
Don't mean to confuse you, but I am remembering all of the "cheap" things that I tried when I had the Castle's (current speakers are not BI-wirable). The best thing that I did (right off the bat) was to get rid of the stock plate jumpers and use a short run of speaker cable instead (big improvement in the mids and HF's).
I have to install some other gear in the living system next week (a preamp and a tuner) in order to test it and maybe I will get around to messing around with TWL's "big" tube idea. I will let you know if I do (I have the magnet wire and tubing on hand). The second system probably won't go up anytime in the near future (the room needs to be cleared out first). |
Dekay, my big tubing is from Lowe's. I think it is polyethelene. I would have liked to have gotten Teflon, but I wanted to get the wires done, and didn't want to wait for mail order. Also, I figured that if the wire was not having alot of contact with the tubing that it wouldn't matter as much. I used 22ga, because my reading of the skin-effect literature said that 22ga is still under the skin-effect depth of copper. Single conductor runs reduce smear. To separate the runs, I used plastic Tee nipples about every 18" and connected them with a 2" piece of tube. This creates a kind of "ladder" appearance to the speaker cables, with the 2 runs staying about 2 1/2" apart. I guesstimated that 2 1/2" spacing would eliminate/reduce field interaction between the feed and return. If this is increasing the inductance, I sure can't hear it in any loss of high freq's. They look pretty exotic.I really don't know how much all this affected the sound, as I didn't A/B them without the tubing, and then with it. I just did it because I thought it would work out right. I am happy with the result. I will say this much: If these wires are holding any of my signal back, then I will sh!t bricks when I hear it with better cables. It is sounding REAL good right now. |
This has been a very helpful thread.
Audioquest says "Simple evaluation of multiple sizes reveals that audible skin-effect induced anomalies begin with a strand (or conductor) larger than .8mm. A much smaller strand yields no benefits but encourages the problems discussed below....".
http://www.audioquest.com/theory/theory2.html
.8mm = .0315" dia = 20 gauge wire = maximum size wire to use
I don't know about the benefits of lacquer vs. enamel but since the magnet wire I found is enamel so I'll go with that. Enamel should be more durable and less prone to cracking than lacquer.
Dekay, large diameter teflon tubing is expensive. Here are prices for 3/8" i.d. x 1/32" wall teflon tubing from http://www.mscdirect.com. You may need to buy 100 feet at a time.
Part number.....type of teflon.....price per foot
48700090........PTFE teflon..........1.66
48702096.........FEP.................1.83
48701098.........PFA.................3.40
heavy wall - 1/16 thick
48702591..........FEP................3.99
48701593..........PFA................5.96
Dekay, do you have a link for Michael Percy magnet wire? |
If you want heat shrink teflon tubing:
http://www.mcmaster.com has teflon moisture proof tubing for $10.00 for 4 foot length. .015" wall thickness. P/N 7960K31.
"The PTFE outer layer shrinks for a tight fit and the FEP inner layer melts to provide a moisture-proof seal."
You could build up a couple of layers and get a similar construction as the 47 Labs OTA stuff. |
Hi CDC: A couple of layers is $5/ft (I would just purchase another 47 Labs kit, which is less expensive, if I could budget this:-).
Michael Percy is @ percyaudio.com and he has a catalogue download (I use PayPal when ordering).
Glad to hear that the new cables sound good (give them 50 hours, or so, of playing time and don't get upset if they have their ups and downs during this period of time). Not having HF/LF rolloff, means that you are within the realms/synergy of your system, good go.
I don't really know the difference between lacquer/enamel though such is detailed in a thread @ A'gon by a member named Tesla. If the RS wire uses enamel then this is OK (I like the sound of them).
The tubing sounds like "lab" tubing. I used this for bare wire IC's and it sounded very nice. Guess that it depends on how much wire contact is taking place?
Yes, the tubing is funky looking (kind of hard to sell such a commercial cable:-), but who cares if it sounds good and meets one's budget?
I have a 35 ft roll of thick 18 gauge Teflon tubing from Fry's, a local store, that was $7.95 (can't remember what I bought it for). I will check to see if they have a larger size then next time I am in the area. |
Any thoughts on silver or square magnet wire?
Naim uses square wire for some reason.
http://www.audiotweaks.com had people using 18 ga silver wire for $1.50/ft from http://www.tobackgold.com and putting 100% cotton shoe lace over it. Less resistance so can use a smaller guage wire for skin effect but less resistance than copper. |
CDC: Never tried square wire. There was a thread (in the past week) @ Audio Asylum (in the cable forum) about the use of "soft" silver 18 gauge "round" speaker wire (its use required twisting in order to get it to sound right). I prefer copper over silver in the signal path, though have only experimented with Kimber, Homegrown Audio, silver cables from some tube preamp guru (can't remember his name) and a few of my own designs which used 26 and/or 30 gauge solid core silver. Per the poster this "soft" silver has a warm sound to it and does not require a lengthy break in period. I would like to give it a try, one of these days, for phono cables and for an interconnect that uses a rather odd design (I need bare silver for the IC). If Toback is in NYC then this may have been the source of my silver wire (the name sounds familiar).
I have listened to a few copper "ribbon" designs (speaker cables and interconnects) and thought that they all recessed the mid's a bit. I did not care for them, but others who were present liked them a lot.
One thing that I forgot to mention about "thin" single runs is that the left and right channel cables need to be separated from each other (8" to 12" apart is fine). This goes with many traditional cables, as well, but the single runs seem to be even more sensitive to this. The same goes with IC's (keep the left/right channels away from one another), and keep all cables off of carpet/rugs, etc., especially if they are made from synthetic materials. This is just another free tweak that improves the sound. I don't use anything fancy for this (just hang them from one component to the other if possible and if the cable is too long then I "hang" it with cotton ribbon from my wife's sewing supplies).
I will check out Audiotweaks in the morning (have not been there for a long time). |
I have never used silver wire in my speaker cables. I did use it once in a preamp I modded, and it was too bright. If you use a SET amp w/ transformer induced problems like high-end rolloff, it can be used to somewhat compensate for that. I really don't like to use cables for tone controls though. Better to resolve the problems at the root.
I don't know of any inherent advantage/disadvantage with square section wire. You'll just have to take your skin-effect depth measurement off the diagonal. I am not the ultimate cable guru. I just made some DIY stuff that had some good design basis behind it, and it worked out. You can too. |
