Duelund conversion to DIY Helix Geometry Cabling

What a wonderful read! Thank you all for the sharing.

I have two questions that I cannot find a clear answer from Steve's site or in this thread.

1. For USB cable, is there significant improvement from AWG24 to AWG18? The USB type A and B connectors are usually designed for AWG24 and thus the question.

2. For double-double XLR interconnect build, what is the exact structure? a) Four runs of wires in total, with the V+ and one ground wire forming a helix set, and the V- and the other ground wire forming another helix set. b) Six runs of wire in total, with two V+ gentally twisted, two V- gental twisted and slightly apart from V+, and finally two ground wires forming a helix structure surrounding singal wires? c) or other?

Thanks a lot.

Wayne

@wyan001 - I’ll leave any comments on the USB cable to @grannyring since it his design and I have NO experience with this particular cable

The XLR design on my web site is from another DIYer in Europe and is a single/single design.

I am not sure if anyone has tried a Double/Double version - anyone built one?

I am not sure if anyone has tried the "Air" aaption either - anyone built one?

If I were to try building an XLR cable I would definitely go for the "Air" Adapton but opt to build a Double/Single version as follows:

For each of the +ve and -ve conductors I would use

- 2 x 18 or 20 gauge bare wires with each wire in their own Teflon tube

- twist the two wires "gently" together (one tiwst every 3-4 inches)

- NOTE: do not bother twisting the the two assembled conductors together - simply insert inside the Helix Coil

- For the Helix Coil I would used a 1 x 16 gauge Solid Neotech Solid UP-OCC wire with Teflon insulation

- but 2 x 16 gauge Solid Neotech Solid UP-OCC wire for the neutral Helix Coil could be used for a Double/Double design

- you could also try 2 x 18 gauge solid UP-OCC wire with Airlok Insulation from VH Audoi for the Helix Coil - the Airlok insulaton has a slightly better Dielectric Constant value

PLEASE NOTE - for the Air adapton the internal diameter of the teflon tube used only needs to be approximately 20%-25% wider than the diameter of the wire, which assures adequate air gap between the wire and the sides of the tube

If you do NOT want to use the Air adaption simply use insulated wire for the +ve and -ve conductors - For this I would use 2 x 18 gauge solid UP-OCC copper with Airlok insulatoin from VH Audio.

Hope that helps - Steve

Dear Steve,

Thank you very much for the quick response.

Another relevant question, if I have the choice to go with XLR or RCA interconnects within 2 meters (by buying or building custom-tailor (pre)amplifiers）, will Helix XLR be a better choice than RCA interconnect? You see, traditional wisdom usually says balance wire is better in trasmitting signal. However, Helix structure seems to greatly prevent noise pickup, as well as signal modulations between signal and return path, and therefore RCA interconnect might be very safe in this regard.

Thanks again.

Wayne

@wyan001 - XLR or Single ended - that is the question.

Perhaps this is where synergy comes into play?

I know that some prefer the XLR verson, while others prefer the Single ended version. But they all state that the improvements of one over the other are miniscule.

Pehaps it is all down to the components in the system - they could have better circitry specific to one or the other.

It could depend on the quality of the XLR plugs that improves on the single ended cables

But - if there is lots of EMI/RFI in your "environment" then the XLR would be the way to go

The only real way to find out is to build both and try them.

Ufortunately I do not have XLR inputs on my amp so I am unable to compare them them.

Regards - Steve

I support Steve's statements.

Anything longer than 2m use XLR.

Find out, if your components both sides are fully balanced internally and not using a chip to only convert input/output signal from single ended to balanced.

However, I never experienced a negative effect from balanced cables, they always are at least "on par" with single ended.

Beside the wires you use, it is important to use good plugs and a good soldering technology with good solder. The wire must make direct contact with the solder pocket in the plug and use minimum amount of solder. The solder should only keep the wire in place and not "be" the conductor.

Therefore I do not use "lead-free" solder with no high silver content, as the conventional solders without lead melt at lower temperatures and "flows" better.

I use either Wondersolder or Cardas. Much preferred over all the lead free 4% silver solder from Mundorf, Furutech, etc.