A Custom Audeze Balanced Headphone Cable

Anyone who has their hands close to the pulse in high-end headphones has heard of the Audeze. Formed in 2009, they have quickly developed a superb reputation for their planar magnetic headphones, the LCD-2, and very recently the LCD-3. Both headphones make use of a very convenient removable cable mechanism employing a pair of mini 4 pin XLR connectors. Switchcraft makes these for about $8 a piece, and you can find generics for less than half of that. As previous experience dictates; Switchcraft's connectors generally prove to be reliable over time, so I'll be sticking with those for this build. The male and female mini XLRs come in a variety of opening sizes to accommodate different cables. For the females that will be needed for the Audeze cable, the small opening version is the TA4F, and the larger opening is the TA4FLX. Below are photos of the TA4FLX.

The Switchcraft TA4FLX 4 pin mini XLR female

Since each driver only needs a signal and ground, and each mini XLR has four pins, the pins are shorted so that the signal uses pins 1 and 4 and the ground uses 2 and 3, as seen in the below diagram.

These tiny little solder tabs require care to solder to and see the numbers associated with each pin. A lamp can be very helpful to get a good look at the connector while working with it. Neotech UP-OCC copper was used to short the pins below. 

Shorted Switchcraft mini XLR pins

Now comes the time to braid the wire for the cable. The process is started by trimming four identical lengths of wire, then braiding it in a litz up until around 18 or so inches from the end. The last bit of wire is split into two twisted pairs, on for each cup. This particular cable will be made using Cardas litz copper wire in Teflon. Cardas litz wire is a number of different gauges of wire, each covered in enamel that needs to be melted away with hot solder (a solder pot is especially helpful). This needs to be done for each end that is stripped.

Braided Cardas litz wire in Teflon

The wire is now sleeved with black nylon multifilament, 1/8" for the twisted pairs and 3/8" for the four wire litz. A ViaBlue splitter was placed over the "Y" split of the cable to give it a sleek look. If you'd like more details about the ViaBlue SC-2 splitter, please read my post regarding a ViaBlue Mini to RCA cable build. 

Prepped and sleeved cable

Since the wires are all the same color, it can be beneficial to color code them to later reference. Hardware stores carry electrical tape in a variety of colors. Typically ground connectors are labelled green, right signal is red, and left is black or white. This isn't always the case, but one can choose a convention for themselves and stick with it. It prevents one from having to pull out the multimeter too often. 

Labelled wires

This headphone cable is going to be balanced, for a balanced amplifier. There isn't an "official" balanced headphone connector, but there are two methods that are the most common; a dual-three pin XLR where only two of the three pins on each connector are used, and a four pin XLR where all four pins are used. This is discussed in greater detail in an earlier DIY Balanced Adapter Cable post.  I'm personally of the opinion that a 4 pin XLR should be used; it's a cleaner, easier cable to produce and a lot less heavy if using a balanced to single-ended adapter. The wire is now soldered in place. The typical wiring configuration for a 4 pin XLR is as follows:

Pin 1 - L+
Pin 2 - L-
Pin 3 - R+
Pin 4 - R-

A piece of heatshrink holds the nylon sleeving in place, and the strain relief grip is placed under the 4 pin connector.

4 Pin Neutrik male XLR connector

The metal sleeve is slipped on top of the 4 pin connector and the plastic strain relief grip is covered by the bottom piece which screws in place, creating a strong grip on the heatshrink and nylon sleeving. 

4 Pin XLR attached

The Switchcraft 4 pin mini XLRs are then soldered in place. As mentioned above, the signal uses pins 1 and 4 and the ground uses 2 and 3. The cable is now complete.

Completed Audeze LCD-2 cable

A balanced adapter was constructed so the headphone could be used with single-ended amplifiers. If you'd like to read how this was constructed and learn a little more about balanced headphone operation, visit the Balanced to Single Ended Adapter Cable post.

Completed cable with balanced adapter

Also built for the Audeze LCD-2 was an identical cable using Kimber TCSS copper in Teflon wire. The Audeze has what I would consider a warmer and more laid-back presentation. The Kimber wire helps bring it forward a little bit without being harsh.

Balanced cable for Audeze headphones w/Kimber wire

If you are looking for your own custom made Audeze LCD-2, LCD-3, or LCD-X cable, Contact Zynsonix Audio for a superb sounding Trebuchet Audeze headphone cable, made with 99.99997% pure, custom ohno cast copper.

Zynsonix is an authorized dealer for Audeze headphones which include not only a full factory warranty, but a free Trebuchet headphone cable. Contact Zynsonix for details.



The Fine Print:
The above steps detailing the building of a cable are for entertainment purposes only, and not to be performed under any circumstances. The owner of this blog and all associated parties can not / will not be held responsible if you attempt the process posted and cause physical harm to yourself, your surroundings or your property. Please keep this in mind.

A Balanced to Single-Ended Heaphone Adapter Cable

Balanced circuits have been around for quite some time, but the first commercially available balanced drive headphone amp was created by Headroom nearly ten years ago. Balanced drive doubles the slew rate and voltage swing available from a circuit and reduces distortion. For balanced headphones, it also eliminates the ground connection between the left and right drivers, preventing crosstalk. There are many headphone amp manufacturers producing balanced headphone amplifiers now, including Ray Samuels, Eddie Current and Bottlehead just to name a few.

There isn't an "official" balanced headphone connector, but there are two methods that seem to be the most common; a dual-three pin XLR where only two of the three pins on each connector are used, and a four pin XLR where all four pins are used. Headroom, being the first to market with their balanced headphone amplifier, went with a dual-three pin XLR. Many manufacturers offer both options. I'm personally of the opinion that a 4 pin XLR should be used; it's a cleaner, easier cable to produce and a lot less heavy if using a balanced to single-ended adapter. 

The Eddie Current Balancing Act Features both 3 and 4 pin connections

Headphones, in order to be balanced, require a complete recable or a retermination if the left and right ground are isolated from one another. Balanced to single-ended adapters are used when someone has had their headphone recabled or terminated to a balanced connection but wants to listen to a single-ended headphone amplifier. In the case of the 4 pin, it's a 4 pin XLR connector to a TRS cable. This cable connects the two grounds to the Sleeve, the "S" of the TRS (TRS stands for Tip, Ring Sleeve). 

In this post, I will be creating a 4 pin XLR connector to a TRS cable using a 4 pin gold Neutrik XLR jack, a Furutech TRS (FP-704 G) and some Cardas litz wire in Teflon. It doesn't appear that there are any boutique 4 pin XLRs at the time of this writing, but the Neutrik 4 pin should not be discounted, it is very well made and solid.

My adapter cables are typically one foot in length, they can be less, but the connectors themselves are large and there should be appropriate space between them so the cable has plenty of room to bend. The process is started by trimming four identical lengths of wire. Cardas litz wire is a number of different gauges of wire, each covered in enamel that needs to be melted away with hot solder (a solder pot is especially helpful). Each length of wire is stripped at the end, the enamel melted away, and soldered to the solder tabs on the 4 pin XLR. One can cover the solder tabs with heatshrink to be extra anal ;)

The wire is then braided into a litz configuration in preparation for sleeving. 

3/8" Black Nylon multifilament sleeving is trimmed with a hot knife and slipped over the braided wire. Two pieces of heatshrink holds the nylon sleeving in place, and the strain relief grip is placed under the 4 pin connector. 

The metal sleeve is slipped on top of the 4 pin connector and the plastic strain relief grip is covered by the bottom piece which screws in place, creating a strong grip on the heatshrink and nylon sleeving. 

A logo'd piece of heatshrink is added underneath the existing piece so it will be exposed under the Furutech connector. The other side of the wires are stripped and tinned with solder. 

The Furutech TRS is dissasembled in preparation to be attached to the cable, you'll see the four pieces below.

The wire is now soldered in place. The typical wiring configuration for a 4 pin XLR is as follows:

Pin 1 - L+

Pin 2 - L-
Pin 3 - R+
Pin 4 - R-

Therefore pin 2 and 4 are connected to the sleeve of the Furutech, pin 1 the tip (left channel), and pin 3 the ring (right channel). The plastic strain relief grip is set in place under the TRS and the metal top and bottom are slipped in place.

The metal top portion of the connector compresses the strain relief grip, the bottom metal portion can now be screwed in place. 

The cable is now complete and is checked with a multimeter for continuity and resistance. 

I hope you enjoyed this step-by-step process of building a balanced to single-ended heaphone adapter cable. Zynsonix can build you one just like it or one built to your specifications.

The Fine Print:
The above steps detailing the building of a cable are for entertainment purposes only, and not to be performed under any circumstances. The owner of this blog and all associated parties can not / will not be held responsible if you attempt the process posted and cause physical harm to yourself, your surroundings or your property. Please keep this in mind.

Mini to RCA Cable with some ViaBlue Connector Bling

The mini to RCA cable is a great option when you want to plug a portable device like an iPod / MP3 player or portable CD player (anyone still have one of those? ) into your home stereo. Modern smartphones let you stream radio stations and services like Slacker Radio and Pandora, why not plug all those great options right into your stereo?  You may have seen my other Mini to RCA Cable blog post, but I will be putting a little twist on the basic cable design with some beautiful ViaBlue connector bling.

ViaBlue is a relative newcomer in the vast sea of audiophile boutique connectors from companies like Cardas, Kimber and Audioquest. Their connectors are designed in Germany and have a unique visual appeal with their gold plated tips and matte black shells. Building using their connectors requires a little bit more effort than other connectors, at least in my experience. The design makes use of allen head set-screws, which require one to build up a large amount of heatshrink so the screws have something to "bite into" as a strain-relief system. I personally prefer a crimp-around ground terminal or the system that Furutech and Neutrik uses with some of their connectors which compresses a plastic sleeve with plastic ridges that secures the cable, but some sacrifices must be made for good looks I suppose ;) 

My favorite connector that ViaBlue makes, the Y-split cover, specifically the SC-2 Splitter 44920 in this particular build, is great for covering up unsightly "Y" splits where the whole cable run enters and two runs exit. These splitters are perfect for headphone cables, mini-to-RCAs, speaker cables and a variety of other applications. 

The ViaBlue SC-2 Splitter

The other connectors that would be used for this build are the T6S RCA Plugs and the T6S 3.5mm Phono mini plug. All make use of the set screw strain relief system and have the same sleek logo printed on the barrel. 

A bevy of beauties

The wire that would be used for this build is military spec silver plated copper in PTFE dielectric. The cable is a hand-braid of four wires, two for ground (or return), one for left signal and one for right signal. The wire in braided as a four wire litz for about five of the six feet of this cable, the final foot being two twisted pairs. 

Hand braided litz of silver plated copper wire

Once the wire has been braided, it can be sleeved. Black nylon multifilament was chosen for this purpose as the matte black on the connectors will match nicely with the soft black nylon. 

Cable sleeved in black nylon

The first step once the cable is sleeved is to attach the SC2 Splitter where the cable splits. 6 or so layers of heatshrink (preferably adhesive) must be built up so the splitter can get a grip on the cable and not move around once it is completed. 

Heatshrink built up for ViaBlue Splitter

The heatshrink should be as large as possible but still be able to fit through the bottom of the splitter. The gold allen screws are scewed into the heatshrink tightly, but not so tightly that they strip. 

ViaBlue Splitter in place

Next comes the mounting of the RCA connectors. The two gold allen screws are removed to gain access to the solder tabs within the plug. 

Opened ViaBlue RCA

Heatshrink is built up at the ends so the screw can grab onto it, in this case it is 3 pieces of 1/4" heatshrink overtop of 1/8" black nylon multifilament.

Extra heatshrink added to ends of cable 

The black plastic spacer and barrel are slipped onto the wire before soldering.

Wires soldered to the ViaBlue RCA

Everything is lined back up and the screws are replaced in the unit. The other RCA is installed the same way.

ViaBlue RCA fully attached

Next comes the 3.5mm mini connector. 

Opened ViaBlue 3.5mm mini connector

Two layers of 1/4" heatshrink are placed on top of the 3/8" nylon sleeving on this side of the cable. The black plastic spacer and barrel are slipped onto the wire before soldering. The solder connection to the left and right are rather close, so I added a piece of heatshrink to keep them secure and isolated. 

Wires soldered to the ViaBlue mini

The barrel and plastic spacing piece are lined back up and the screws are replaced.

ViaBlue mini fully attached

With all connectors in place, the signal and resistance is checked with a multimeter to verify signal continuity and that there are no shorts. The cable is now complete.

Mini to RCA with ViaBlue connectors

A second angle

I hope you enjoyed this documented step-by-step process on creating a mini to RCA interconnect with ViaBlue connectors. This cable was a special request taken at Zynsonix, where you can purchase the same cable or one built completely around your specifications.


The Fine Print:
The above steps detailing the building of a cable are for entertainment purposes only, and not to be performed under any circumstances. The owner of this blog and all associated parties can not / will not be held responsible if you attempt the process posted and cause physical harm to yourself, your surroundings or your property. Please keep this in mind.

JDS Labs CmoyBB v2.03 Headphone Amplifier

The CMoy headphone amplifier came about many years ago as an invention of Chu Moy on the HeadWize headphone board. It was a simple and low-parts design featuring either a single or dual-channel op-amp. There have been many iterations of the CMoy since it was introduced, many of which are put together on a proto-board, and are traditionally stuffed in a Altoids Tin.

A traditionally built CMoy

During a day of wandering the interwebs, I stumbled upon JDSLabs website. JDS has created what he calls the CMoyBB, which is very simply, a CMoy with Bass Boost. In the interest of a simple build, a circuit board was created that fits perfectly within an Altoids tin (including the rounded edges). Depending on one's preferences, a rechargeable version can also be built.

The CMoyBB v2.03 board in beautiful red

There was some notable innovation involved with this design. According to JDS: The cMoyBB v2.03 uses a top-layer ground plane and tightly optimized signal traces, easily outperforming hand-soldered protoboard connections. Proprietary software was used during design of the PCB to check for proper impedance characteristics and negligible crosstalk. Sounds great, where do I sign up? :)

The JDS Labs website has everything you need to get started. The PCB, as well as a number of parts and accessories are carried for your convenience. The documentation is incredibly well laid-out, and includes myriad options should one decide to stray from the standard build. The only thing you need to do is make a quick trip to Mouser with the bill of materials and get the remaining parts. All items below, aside from the Altoids tin and OpAmp socket, were from JDS.

A semi-populated CmoyBB board and Altoids Tin

Between a few parts I had in the parts bin and a Mouser order, the PCB is nearly done. I had a nice 9V battery strap I had procured that's made of hard plastic rather than the typical flimsy PVC you find on some straps. For the film caps, I chose to populate the board with WIMAs, the resistors are nearly all hand-matched carbon film aside from the 10.2K which isn't available, so metal film was used in that position.  As stated ad nauseum in other posts; I prefer carbon film over metal film. The Burr Brown OPA2227PA was chosen for Opamp duty, as I prefer the generally warmer, bassier sound of Burr Brown OpAmps as compared to the general sound of Analog Devices OpAmps. This little board will be configured for single 9V battery operation, so ignore the little yellow capacitor in C5 in the photo below; it won't be needed. 

The fully populated board minus LED

When preparing an Altoids tin (or any other thin tin packaging), delicacy is a must. Either a good quality hole punch should be used, or a hand-drill and Dremel combination with some patience. The latter involves making a very small hole with the drill, then slowly enlarging it with Dremel bits. The hole punch is much easier, but it can be difficult to procure a high-quality one that will punch metal easily. Below is a photo with the 5 holes punched in the tin and some electric tape placed where the PCB will sit. This will prevent any unwanted shorting of the soldered traces on the underside to the tin. 

Punched and prepped Altoids tin

Now the board can be placed inside the prepped tin. Once everything is fit where it is supposed to be, the nuts are screwed to the 1/8" jacks, the knob is placed on the potentiometer shaft, and the plastic grommet for the LED is placed in the corresponding punched hole. The 9V battery is then attached to the battery straps and a piece of adhesive foam placed along the side of the tin. This will prevent the battery from moving about during transport. A small piece of Dynamat was placed underneath to further cushion the battery.

Completed CMoyBB

Here's a photo of the completed amplifier with the case closed. Note that the area above the knob was dremelled away to allow unimpeded volume adjustment. 

Completed CMoyBB - Closed

This was a very quick and enjoyable little project from JDSLabs, and one of the most well thought out CMoy amplifiers I've seen. If you like headphone amplifiers in small candy tins, be sure to check out my post on the Miu Audio RA-1 Amplifier. 

Looking for a custom audio cable for your portable device or amplifier? Zynsonix Audio offers a number of great solutions.  

The Fine Print:

Please remember that building circuits and performing circuit modifications can be dangerous to you and/or your surroundings and should only be performed by a certified technician. The owner of this blog and all associated parties can not / will not be held responsible if you attempt a build or modification posted above and cause physical harm to yourself or your surroundings. Many electronics contain high voltages that can kill, and mods, if performed improperly, can be a fire hazard. Please keep this in mind.