Is shielded interconnect (RCA) best for connecting FM tuner to amp?
- Thread starter DNZ
- Start date
ICs are not routinely coax.
Most ICs that use coax use the shield as one conductor, not as a screen - they use screened simgle cable, but not used as intended by the design. To provide a screen, screened twin is required - two conductors plus a screen.
The signal between a tuner and pre/integrated amp is no different to the signal betwen a CD, or tape, or phono amp, and the pre or integrated amp.
I reckon screened twin ICs cut an enormous amount of noise here. Try some and see what you think.
Most ICs that use coax use the shield as one conductor, not as a screen - they use screened simgle cable, but not used as intended by the design. To provide a screen, screened twin is required - two conductors plus a screen.
The signal between a tuner and pre/integrated amp is no different to the signal betwen a CD, or tape, or phono amp, and the pre or integrated amp.
I reckon screened twin ICs cut an enormous amount of noise here. Try some and see what you think.
adamdea
You are not a sound quality evaluation device
This is news to me. There does exist something called twinaxial cable but that’s a different thing. There are reasons why single ended shielded signal cables are coaxial. It’s to do with the need to have the shield at a constant distance from the conductor and having the geometrical centre of the signal and return coinciding.
unshielded cable is a different thing.
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Screened twin is used as an IC, with a screen, by using the twin conductors as positive and return/ground, and connecting the screen, ONE RCA only, to the ground.
Screened twin ICs can be bought ready-made, although I have no idea if they're wired correctly - I made all my own.
Common screened twin cables are Klotz MC5000 (the common one offered commercially) and Van Damme Classic XKE pro-patch. I use the Klotz - a microphone cable and quite large. The VD is small and suitable for one channel of a tonearm cable and is commonly used as guitar and microphone cable (often at eye-watering prices as ready-mades).
I am unsure about the VD - it will be online somewhere - but the Klotz is low cap'.
Shop around and the Klotz in particular can be bought for peanuts (though a lot more expensive than pre-covid, as with all metals and high metal content articles).. Before C19, I paid 60p/m for Klotz and £1.50/m for VD XKE (beware - VD XKE is a range of cables - you need the pro-patch).
Screened twin ICs can be bought ready-made, although I have no idea if they're wired correctly - I made all my own.
Common screened twin cables are Klotz MC5000 (the common one offered commercially) and Van Damme Classic XKE pro-patch. I use the Klotz - a microphone cable and quite large. The VD is small and suitable for one channel of a tonearm cable and is commonly used as guitar and microphone cable (often at eye-watering prices as ready-mades).
I am unsure about the VD - it will be online somewhere - but the Klotz is low cap'.
Shop around and the Klotz in particular can be bought for peanuts (though a lot more expensive than pre-covid, as with all metals and high metal content articles).. Before C19, I paid 60p/m for Klotz and £1.50/m for VD XKE (beware - VD XKE is a range of cables - you need the pro-patch).
Pro Grade Classic XKE Pro-Patch Cable | Van-Damme
Grade classic XKE pro-patch cable was designed to suite Neutrik and Switchcraft bantam jacks using a lower OD cable.
www.van-damme.com
les24preludes
pfm Member
I also made my own interconnects. I started with the Klotz as above and found it quite dull. I then made interconnects with teflon PTFE coated silver plated copper multi-strand. These were made as twisted pairs - no noise issues at 2V line. Much better - lively, detailed, in fact very good indeed.
So if you are making your own then move up from Klotz and the other coaxial types and go twisted pair with higher class cable. You will be surprised at the better sound you will get.
That is what the Klotz replaced here - twisted pair, PTFE etc.. Klotz far better.
Everyone's ears and systems are different. For me, the difference is between shielded and not, but I have used very few different ICs and would never pay "silly" money for any cable.
les24preludes
pfm Member
I'm surprised, but there we are. Teflon PTFE coated silver plated copper multi-strand twisted pairs were clearly better sounding to me.
I quite agree - I'd never pay silly money for cables. £50 should cover all your interconnect needs if you make it yourself. £100 tops if you use boutique RCA connectors. I just use generic gold ones off ebay.
adamdea
You are not a sound quality evaluation device
I don't claim any expertise but I think the cables you are both using are primarily designed to be used by mics with xlr connectors*, which would explain why they aren't coax. @Jim Audiomisc can you assist?
*see eg https://www.van-damme.com/vandamme_...sic-xke-pro-patch-cable/#product-applications
"Applications
For mic and line level analogue balanced audio"
*see eg https://www.van-damme.com/vandamme_...sic-xke-pro-patch-cable/#product-applications
"Applications
For mic and line level analogue balanced audio"
@adamdea, you are the only person here to mention coax.
Strictly speaking coax (short for coaxial) cable/flex is two conductors that are coaxial and most frequently are a conductor and a screen. To be coaxial, there is no other configuration possible, except multiple concentric (coaxial) "screens". In many instances, the centre conductor is actually solid (cable), not muti-strand (flex). It is typically used as aerial lead.
Hifi ICs require two conductors. There may or may not be an additional screen. The conductors may or may not be coaxial, if they were coaxial it would have to be in the same configuation in the cable, as a screened single cable - typical "coax".
High quality microphone cable is typically screened twin, so can fit the bill as a screened hifi IC.
I also stated common uses for both Klotz and VD cables above - microphone cables.
At the end of the day, all of these things are lengths of insulated copper conductor in various configurations. So long as the current carrying capacity and insulation resistance (voltage rating) are appropriate, any can be used for anything.
Strictly speaking coax (short for coaxial) cable/flex is two conductors that are coaxial and most frequently are a conductor and a screen. To be coaxial, there is no other configuration possible, except multiple concentric (coaxial) "screens". In many instances, the centre conductor is actually solid (cable), not muti-strand (flex). It is typically used as aerial lead.
Hifi ICs require two conductors. There may or may not be an additional screen. The conductors may or may not be coaxial, if they were coaxial it would have to be in the same configuation in the cable, as a screened single cable - typical "coax".
High quality microphone cable is typically screened twin, so can fit the bill as a screened hifi IC.
I also stated common uses for both Klotz and VD cables above - microphone cables.
At the end of the day, all of these things are lengths of insulated copper conductor in various configurations. So long as the current carrying capacity and insulation resistance (voltage rating) are appropriate, any can be used for anything.
adamdea
You are not a sound quality evaluation device
I don't want to get bogged down here but
1) the fact that the signal and return are dissimilar is a potential weakness in coax compared with proper balanced cables; but
2) this does not make coax unsuitable for hifi rca terminated cables. All coax cables have a signal and return, the geometry is not a mistake its a feature and that is why coax is used for lots of critical applications like analogue video. All of them use the screen as return too. That really is how they are supposed to work. The idea that it is being misused by having screen and return as the same conductor is a piece of audiophile misconception. Look at what van damme recommend for hifi interconnect -it's coax
Up-LCOFC Hi-Fi Twin Interconnect Cable | Van-Damme
Up-LCOFC hi-fi twin interconnect cable is perfect for use with quality phono connectors such as the Van Damme phono. Each element combines to create a transparent high end interconnect.
www.van-damme.com
Anyway the crucial point is that most of the time this doesn't matter so you can use the wrong cable and it will work, and probably work fine. But if you want to get maximum screening protection from an rca connector (which did seem to be the point of the OP) you would want to use coax. The reasons for this are I'm pretty sure based on solid physics.(I think there is a section on this on the blue jeas webite iirc. certinly they have solid measurements for the screening performance of their products.)
Anyway, not meaning to in any way get in the way of your hobby, but the OP asked a simply question and it has a simple answer.
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No, no, no, a hundred times no.
Coax is two conductors. There is no screen if used as an IC - what should be the screen is used as a conductor.
If you want a screened IC, you MUST use screened twin.
I'll PM my address and you can hear the difference in background noise between un-screened and screned twin ICs - it is considerable, or it was when I first tried Klotz. Maybe a fluke one-off, maybe the environment is especially noisy here in radiated electrical terms.
adamdea
You are not a sound quality evaluation device
Nope that's really is how coax cables work. I'm afraid this is just one of those things which is counter -intuitive but true.
[Edit: see https://www.st-andrews.ac.uk/~www_pa/Scots_Guide/audio/part6/page3.html
also, blue jeans cable explanation for why coax is the correct topology for unbalanced analogue audio signals/the fallacy of using twin signal cables https://www.bluejeanscable.co.uk/articles/balanced.htm
and their measurement of comparative shield resistance of coax as compared with analogue microphone cable (Belden 1800F) https://www.bluejeanscable.co.uk/articles/humrejection.htm ]
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Electrical cables and Screening
Using screened cables and isolation from noise. How to terminate and keeping noisy cables separate from signal cables.
@DNZ - where are you? What length IC?
I have some spare Klotz/Neutrik Profi IC's here. Pay for postage and you can try them, if you like them, they are yours for the cost of parts (Neutrik Profi are not cheap, the cable is and even I usually foget that a pair of IC need two pairs of plugs whenever I go to make up another set).
Use PM
I have some spare Klotz/Neutrik Profi IC's here. Pay for postage and you can try them, if you like them, they are yours for the cost of parts (Neutrik Profi are not cheap, the cable is and even I usually foget that a pair of IC need two pairs of plugs whenever I go to make up another set).
Use PM
I'm in New Zealand - it's very kind of you to offer.
For the tuner I am using at the moment (a Quad 66 FM which is not mine) I am currently using the RCA interconnect that came with my Accuphase CD player. My dealer sells Kimber most of which is braided and not shielded - but he says that with tuners, because you are attaching an aerial to your system, it's best to use a shielded interconnect to keep the noise floor as low as possible - which is why I asked the question really.