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Is this a new version of that ‘legs or hotdogs’ meme from a while back?
Knees or butt?
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Cable with one direction
- Thread starter DanielT
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Is this a new version of that ‘legs or hotdogs’ meme from a while back?
Knees or butt?
Bob from Florida
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I make all my interconnects this way and they work fine. If you have a long cable run - use balanced, assuming your gear supports this. Use a basic "sound" cable and all is well. Money wasted on fancy "audiophile" cables is much better spent on music for listening pleasure.
OP
DanielT
Master Contributor
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I just put that video in for the sake of the picture. I am not interested in "High End" expensive cable. Sensible "standard" cables that work together with RCA connectors that clamp just enough and I'm good to go.
By the way, RCA connectors that clamp too tightly are a nuisance.
Luckily, I don't need particularly long cables, so that makes the whole thing easier.
Bob from Florida
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Theoretically, might make a difference with RF shielding. In reality, probably nothing anyone would hear in a blind test. The cable itself is easier to work with than RG6 coax for example. From a practical standpoint, if you needed to convert to balanced and did not have enough raw cable leftover, you could remove the RCA plugs and replace with XLR.Interesting that you do that.
How did you come to choose semi-balanced RCA vs unbalanced ditto? Did you experience problems with unbalanced RCA cables?
No difference if there is no ground loop current that can flow through the shields. There is a difference if ground loop current is possible, and a cable with both ends' grounds connected is used. A way to get around that would be to single point ground the pieces of equipment with external ground wires, and then going with interconnects that have the ground connection only on one end.
I highly doubt there'll be any problems. I used to have the average hobby enthusiast homestudio, with 30 or more devices connected criss cross, patchbay, mixer, submixer, DJ mixer as final preamp, amp, subwoofer, all balanced and unbalanced mixed (some on the same connection), 50 dozen power supplies running from half a dozen power strips, and as the cherry on top, wild cable salad with line and USB and power cables living happily right next to each other. All cheap stuff too.Thanks for the clarification.
I guess I'm asking for trouble. In the near future from my DAC, via unbalanced RCA, into my two subwoofers, then RCA out from the subwoofers, with the HP filter set to either 50,80 or 100 Hz..
View attachment 389181
..to an active crossover (LD Systems X 223) ..
View attachment 389182
...and from it unbalanced out (possibly balanced to the amp that will power the bass driver) to two amplifiers that power up the bass and tweeter in my speakers. It kind of smells like a problem here even before I got started and plugged it in.
In any case, repainting the living room and new skirting boards are to be installed there, so for now my subwoofers are in storage.
Not a single problem. No hum, no noise, no interference, no ground loops. Ever. I don't know any fellow hobbyist who had any problems like that either, and almost nobody cares about cable management and shielding - because it just isn't an issue generally. You plug the stuff in, it works, done. Press a button, make a noise. Sometimes I wish some audiophiles the same relaxed attitude. You don't need to worry about these things at all, musicians don't either. You only need to fix a problem when there actually is one, which is exceedingly rare.
Compared to the above, your plan seems simplistic and straightforward. I don't expect any issues.
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Maybe for ballanced lines. But how's that work when you need to connect source ground to destination ground in an unbalanced system. So that shield is still connected to destination ground thru the other grnd to grnd conductor. Are there 2 shields, than why would capacitance be different? Is the ground connection just a wire (so the cable is twisted pair with a shield)? Then its not a coax with all the benefits of coax.
I see very little advantage if any from these cables.
Yea its fiber optic with converters. One end puts out light the other receives it. What has this to do with th OPs cable?Even though I assume all of you know very well, high-speed high-resolution "optical" HDMI cables do have "one direction"!
View attachment 389184
I actually use one of these, 10-m long AOC 8K/60Hz 4K/120Hz optical HDMI cable, connecting into Panasonic 55-inch 4K OLED TV (as second PC monitor) from my audio-visual Windows PC; very nice for 4K/120Hz or 4K/60Hz signal transfer into the 4K OLED TV with slim and light optical HDMI cable even 10-m away from my PC (ref. Fig.21 in post #931 on my project thread).
But the source ground is still connected to the destination ground so the noise still gets there.
Almost nothing to do with OP's! Just an example of cable (audio-visual) which has definite "one direction".
There is no such thing. Balancing of any sort needs differential receiver at the destination. Anything with RCA in is not differential.
Using your third pin ground on the power plugs for signal ground and just connecting the centre pins of the RCA. Ever try that? Why don't you try. Turn down your Amp down so the noise/ hum dosnt blow your speakers.
restorer-john
Grand Contributor
Not if both your pieces of gear are earthed. You are actually breaking a loop. But with most modern gear being two-core double insulated, less of an issue.
The entire "twin-core shielded- break the shield at one end and use the inner pair for RCA" is just a bodge.
DSJR
Major Contributor
I used to hold with most single ended cables having a direction and all I asked my clients to do was to 'humour me' and have both cables in a stereo pair running 'the same direction.' As I ventured away from bought w@nky wires, I discovered that general but well specified AV-style cables didn't have a direction at all. I don't care any more to be honest, but if there are arrows on the outer jacket, I'd simply suggest keeping the 'writing' in the same direction
AnalogSteph
Major Contributor
Both of these drivers look fairly well-behaved and actually are of almost the same sensitivity. All hell breaks loose in the woofer above 5.5 kHz though, so you will definitely need at least one rather broad notch for that one. (Low Q is good for you, it means you need a relatively low inductance only, so small series resistance.) The area around 10 kHz is particularly critical.
I wouldn't see a problem with pushing the crossover to 2.0 kHz, the tweeter can definitely take it, especially in combination with this relatively weak midwoofer. I've seen speaker measurements indicating tweeters outclassing their woofers so many times I've lost count. If you want to add some extra passive highpass filtering like a series capacitor to better address the area <1 kHz, I would want to linearize the impedance (flatten out the resonance hump) first. The good thing about an active crossover is that it isn't affected by varying driver impedance.
Of course you can use a normal excursion 5" woofer to 100 Hz. Yes, this one is ideally crossed over at 200 Hz for best level handling, but in practice more typical sub crossovers of 100-150 Hz should be just fine.
Do note that you will have a timing alignment problem simply due to geometry if you put both on a flat baffle. The woofer's effective sound origin is going to be further back than the tweeter's. Making the baffle slanted would be one way to address this issue. If that should turn the affair into a woodworking nightmare, angle the entire speaker up as required and optimize it like that, I can't imagine you need more than 5-10°. That's where a digital crossover could just dial in a bit of delay for the tweeter instead.
On a related note, make sure the woofer and tweeter are properly inset into the baffle and come out flush. (You can do some modelling with an epoxy / wood pulp mix or something along those lines if required.) Also, the "suitable" c-c distance is likely to be the minimum feasible one, given how wide the tweeter's mounting ring is to begin with. (When both are just touching each other, c-c is 75 + 50 mm = 12.5 cm. Sound wavelength even at 2 kHz is only about 17 cm, and ideally you'd want to be under half that, i.e. 8.5 cm.) Some manufacturers of nearfields even trim off something, or some like Dynaudio go the cheap route of mounting the woofer on top of the baffle so they can overlap (see e.g. LYD 5 or BM5 MkIII)... the downside being that the tweeter "sees" a step from the outer ring (followed by the surround), which creates diffraction and disturbs dispersion. There's a reason why all the best speaker designs have super smooth-looking baffles. You can try to "hide" the woofer by modelling something around it à la Neumann and others. A lot of nearfields also have the woofers slightly inset into the baffle, even cheap ones... have a look at the things you find on Thomann or something. Even a lot of the cheap 3"-4" class wannabe monitor sets with their crappy single-capacitor crossovers have super advanced baffle designs.
I would suggest not buying them.but if there are arrows on the outer jacket, I'd simply suggest keeping the 'writing' in the same direction
Bob from Florida
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You guys are really making wonder today. Shielded twisted pair cable - 3 wires total. The twisted pair accomplishes the unbalanced connection. The outer shield is only connected at one end - usually the source side. It has nothing to do with signal transmission only shielding. Please note I never referred to this cable as balanced as it is not. Ground loops are not related to connecting a shield this way.
But you still get ground loops from the twisted pair ground. And the shield is still conected to both grounds thru the twisted pair. And the best cable for unbalanced is still coax, which that is not.
