Heyas folks, time for an update on my cable mod. After messing around with some more ideas, I settled for this final design I am calling " The Cable I built From crap around my house MK. IV ".
But first I would like to explain some embarrassing design choices by PSB. The pictures below show what type of wires (and the mess) are used. While I am no expert, I do know exactly what type of wire should be used in specific applications and why; I have worked with literally hundreds of typed of wire and cable of various construction and design, including copper, silver, and platinum, shielded, unshielded, twisted, solid...you get the idea. The types of wires used in the M4U 1 is comparable to cheap 'dollar store' earbuds, literally.
Pictured here is the stock PSB cable and a cheap $1 earbud cable. Sad.
Notice the same wires used for the inside. While the right photo is of the M4U 2, thus a few more wires present, it does show what type of mess is hiding behind the plate.
You can see why I wanted a new balanced cable. Just think what is happening to the sound when it enters one cup and goes through that rat's nest to the driver and on to the other cup. I highly suspect that is why there is so much bad microphonics present on the actual headphones (more on this below). I am not brave enough to rewire the inside yet, but it is on my things to do list for the future.
Anyway, on to my cable. I had a few feet left on an old spool of 28 gauge 4 wire double shielded data cable that is perfect for this application. I doubled up the leads so now the +/- have 2 wires each per side. As well, both left/right cable feed separately right down to the 3.5mm input lead.
Because of the very narrow opening for the plug insert on the cups finding a usable 3.5mm plug was difficult. Every electronics retailer only carried plugs that were way too large to fit, so split and I cut down my Ultralink 3.5mm interconnect cable so it had a 1" lead, and sanded/shaved the diameter of the plugs so that they could fit.
Using some heat shrink and sleeving I fancied up the cable (for practical reasons). You will notice that the cable has 2 ferro core EFI/RFI dampeners. Originally I had planned to push the black one over the input lead but it would not go all the way down (despite me doing a trial fit before I soldered). So I placed the clamp on one over the leading figure having a second wouldn't hurt. I fact having 2 in series actually reduces the click of my DAC changing sample rates and if I place them up against each other I can't hear the click at all.
So how does it sound? Amazing! However I do want to call myself out on my last post and say while it was correct, it was B.S.! I have a bad habit of saying things expecting others to know what I know and therefore assume people know where I am coming from. Let me back things up and explain.
The headphone cable is literally the weakest link in your chain, just like any interconnect. In the case of analogue signals cable quality does matter more than one may think. What a good cable will do is not enhance anything rather disappears from the chain. What this does is allows the listener to fully appreciate both the source (DAC/Amp) and the output (headphones). So when I say that with my new cable everything is more clear or clean, I hear enhanced bass, smoother mids, and more detailed treble along with a more expansive, almost holographic soundstage , it is both accurate and at the same time not correct. A cable is passive. It does nothing but allow a signal through. It is like looking out a dirty window, and then you clean both sides. This does nothing but allows you to see clearly; In the case of sound total transparency. The glass does not enhance the colour or contrast. Much like how dirty glass can actually cause the light to glare (appearing brighter than it is), so does an inefficient and poor quality cable.
The
'Song Three For All' is one I used for my review. I listened to that song about a dozen times in a row and know every nuance, or so I thought. What I hear with my Mk. IV vs the stock PSB is striking. Just off to the right is a sound of one of the guitarist tapping his foot on the floor. With the stock cable I could hear it but never knew what it was. I had actually assumed that it was the sound of the 'flick of the pick' coming off the last string hard. With the Mk. IV I clearly hear it is a shoe. In fact I can tell what type of sole of on the shoe. The sound is apparent and transparent and easily discernible. Going back to the stock cable I do hear that the sound is the tapping of the shoe, but it os not as upfront and hard to hear; It is akin to hearing a song for years and not knowing the lyrics, then you read them and it sticks even though you still cannot hear the words as they are your brain fills in for you.
The overall presentation is much more detailed and smooth. The main guitar off to the left sounds muddled and smeared on the stock cable. At first it sounds more up front but after switching to the Mk. IV it is clearly heard that the notes on the stock is literally blending in the notes making them sound dull and without sparkle. In fact at the 1:30 mark in the song after song vigorous strumming the 3rd guitar that is the most subtle of the three virtually disappears when using the stock cable whereas the Mk. IV I not only clearly hear it, it has life and twinkle.
In terms of soundstage, the stock cable is flat and dull. I can easily discern the nuances of my iPod, iPod Touch, iPhone 5, and my UD-H01's DAC/Amp. The Mk. IV the sound out of my Teac UD-H01 is almost holographic. The whole frequency spectrum seems to come alive, tickling my eardrums with excitement (no seriously, it does tickle my eardrums in a blissful way). Anything brass has greater bite whether it be cymbals or horns. Bass is more tight and taut. Midrange is more smooth and detailed. Female vocals have a more delicate touch. All in all, I hear the quality of my DAC for what it truly is.
What is interesting is that after I was doing some testing and A/Bing, I started to unwind and listen to some random songs from my 24-Bit HD audio playlist. Song after song I just wasn't satisfied with what I was hearing. Something wasn't right and I assumed it was listening fatigue. I ignored it until my cat jumped up on my lap and pulled out the right cable...and the left driver cut out. I plugged the cable back in and pulled out the left cable and the right driver went out. Whoops, I had mixed up the sides so the left cable was feeding the right driver from the left jack, and vice versa so essentially the signal from the jack was transversing the maze of wires from one side to the other. After swapping sides the sound came alive and slapped me across the face, thus validating my theory that the internal wires are poop! This alone has really really tempted me in re-wiring the internals.
Anyway, all in all I am happy with my Mk. IV balanced cable, especially since all it cost me was time. I do have plans on ordering probably some Sennheiser 3.5mm mini plugs from Alliexpress and seeing if the fit, and probably include an 1/4" plug for my next cable project. Anyone considering doing a similar cable, the rewards are worth it.