Category: Other

27
Feb

Pure OFC Silver Plated Pseudobalanced Interconnects (DIY)

I consider interconnects one of the most important cables in the audio system because the signal level they are transitioning has a low amplitude which makes it sensitive to noises. On the other side, devices on both ends of interconnects are usually sensitive to characteristics of the cables like capacitance and resistance.

Today I will show you how to make a pair of very high quality DIY interconnects using a 99.9998% OFC silver plated wire in a pseudobalanced(semibalanced) configuration. Pseudobalanced(semibalanced) interconnects usually employ a shielded cable consisting of 2 insulated wires and a shield which is connected only on the input end.

Cable: Audiophonics 11467 – 2m (6.5ft) (supplier)
– Cores: 2×0.5mm silver plated OFC
– Shield: silver plated OFC
– Insulation: PTFE
– Total diameter: 3mm
– Costs only 4.92EUR per m

Sleeve: Audiophonics 7835 – 3m (9.75ft) (supplier)
– Cable diameter: 1.5-5.5mm
– Costs only 0.83EUR per m

RCA Plugs: Rean NYS373 – 4pcs (official website / my supplier)

– Maximum Cable Diameter: 6.1mm
– Solid build, long lasting
– Gold plated contacts
– Easy to solder
– Costs only 2EUR each

Total cost: 20.33EUR

Input end (a.k.a source):
At the input end you should join the black insulated conductor with the shielding for a pseudobalanced configuration (only at the input end !). Like this:
DIY Silver plated OFC Input End

And then solder it into the RCA plug:
DIY Silver plated OFC Input End RCA

Outpud end (a.k.a. destination):
At the output end you should leave the shield unconnected at all and make sure it can’t accidentally touch any of the metal parts of the RCA plug. Use only the black and white insulated conductors as shown:
DIY Silver plated OFC Output End

And then solder the insulated conductors in the RCA (don’t forget to slide the rca outer shield to the cable before soldering the connector on the other end):
DIY Silver plated OFC Output End RCA

Make sure to mark permanently which side is input on both channels so you won’t make mistakes when connecting the cable.

Mine looked like this after I was done:
DIY Silver plated OFC Pseudobalanced Interconnect

20
Jul

DIY Silver Plated OFC Shielded Interconnects

Today I will be sharing with you a quick guide for a very high quality DIY interconnects at a reasonable price consisting of a silver plated OFC shielded cable from Schutz Kabel and gold plated RCA plugs from Amphenol.

Cable: Schulz Kabel SL 1 – 2m (6.5ft) (official website / my supplier)
– Core: 64×0.1mm silver plated single copper cores
– Shield: 120×0.1mm silver plated single copper cores
– Outer insulation: PVC with natural rubber
– Middle insulation: Thermoplastic elastomer
– Core insulation: Polyethylene
– Costs only 3.68EUR per m

RCA Plugs: Amphenol ACPR-* – 4pcs (official website / my supplier)

– Maximum Cable Diameter: 7mm
– Solid build, long lasting
– Gold plated contacts
– Easy to solder
– Costs only 2.5EUR each

Total cost: 17.36EUR

Note: If you choose to use another RCA plugs or cable make sure that the outside diameter of the cable is not bigger than the RCAs’ maximum cable diameter otherwise you may find it impossible to fit and fix it in the RCA. For example, the Schulz Kabel SL 1 has an outside diameter of 6.5mm and cannot fit in the popular Rean NYS373 RCA plugs which I found the hard way 🙂

(click to enlarge)
DIY Silver plated OFC Interconnects

15
Aug

Grounding of power amplifiers

Ground loop currents flow through A -> B to the protected earth at point B, and then to mains ground via B -> C. They cannot flow through the audio path so this topology is resistant to ground loops even with unbalanced inputs. The limitation on system performance in the presence of a ground loop is now determined by the voltage drop in the input cable ground, which is outside the control of the amplifier designer. A balanced input in theory cancels out this voltage drop completely.

Seen in Audio Power Amplifier Design Handbook 5th Ed. by D.Self