Update on the new Porta Pro cable

A while ago I changed the cable on my Koss Porta Pro to a new one bought off ebay. You can read about this in my previous blog post. It seemed like a reasonable cable although not the sturdiest. However, considering the original cable lasted me around two-three years I was hoping to get at least a year of use out of this new one. That turned out to be wrong. Today I was going to go for a walk and as the great music fan I am I wanted some music in my ears while walking. To my disappointment I heard only music from the right speaker. The left side was completely dead. I tried replugging the cable to my phone, no difference. I thought maybe there is something wrong with the phone so I tried connecting them to my O2+ODAC combo, but the problem remained. I examined the cable for any visible damage and I couldn't see any. I tried jiggling around the cable along its whole length to see if I can get a connection somehow. No success. I took of the speaker from the frame and opened it up to see if the solder joints were still intact and they were. Apparently the cable must have broken somewhere and I can't find it.

Right now I don't know what to do. A new cable would cost me around 40SEK and a month of waiting and may only last another month or two. A new pair of headphones would cost me 300SEK and would hopefully last at least a year or two. I could try with another, sturdier, cable, such as a normal 3.5mm to 2xRCA but that would probably cost ~80SEK and would require some modifications to the headphones which might not turn out very well. I really like the Porta Pro headphones because in my opinion they are the simply the most portable non-in-ear headphones and they do actually have a decent sound for its price level.

Koss Porta Pro cable replacement guide

My second pair of headphones, the Koss Porta Pro, has served me well the last couple of years and I am surprised at how well they have withstood all the abuse they have been put through. I used them when I was sanding the Oy cabinets. I had them with me on my trip around the world, carelessly packed in my backpack or pockets. They have been with me on over a hundred workout in the gym and then afterwards just tucked in my gym bag along with other items. The frame is still perfectly straight. The foam earpads are looking pretty ok, just a few holes on the edges. The cable has been the part that has handled the abuse the worst. About half a year ago it turned really stiff so it wasn't a very good idea to fold the headphones and then wrap the cable around them. I did that anyways though and eventually the outer insulation snapped in half and it was only being held together by the really thin wires. I solved this temporarily by using some electrical tape. It didn't last very well though and I had to change the tape every two weeks or so. I ordered a 3.5mm -> 2xRCA cable that I was planning to use as a replacement. However, that cable got put in use elsewhere (between the O2+ODAC and my stereo amplifier) so I kept on using the electrical tape. Last week when I was about to go for a walk the sound just died in one side. One of the wires had broken. I managed to fix this with some soldering and lots of electrical tape, a really ugly short term solution. Meanwhile I had ordered a replacement cable from Ebay.

Short term electrical tape solution.

The replacement cable arrived today and I just couldn't wait with replacing the old cable. I found this guide over at iFixit which shows how to disassemble the headphones but also how to do if you have a non-standard replacement cable, similar to what I was planning to do in the beginning.

I decided to write my own guide for you, based on if you have the same cable as I have. I bought this cable from tuttoit on ebay. It is cheap, shipping included and it looks ok. I have no idea about the durability yet but I will come back later to comment on that. As usual it took quite a while for it to arrive but that can be expected when ordering things from Asia with free shipping.

As the iFixit guide mentioned above says you need to start by removing the speakers from the frame. You do this by gently pulling them apart. With a bit of force they will snap off from the frame.

Then you should remove the black foam. It just hangs onto small plastic pins running around the edge on the backside. Gently lift it off the pins and remove it.

Now is also a good time to make sure there is no dirt or hair behind the black cover. That could potentially degrade the sound. If you have had the headphones for a while there will probably be some stuff there. Gently remove it and be careful not to touch the speaker drivers.

The next step is to remove the plastic cover covering the wire. For this you need something pointy, like a flat head screwdriver, knife or similar. Bend gently and it will start coming off.

Take note of how the cables are soldered. Take a picture with your phone or write it down on a piece of paper.

Begin with desoldering the wires to one speaker. Don't do both at the same time. I would recommend trying to be as quick as possible when heating up the joint and removing the cable. The plastic can deform or even melt if you keep the heat on for too long.

New cable soldered to the connector.

As you can see in the picture above I kept the heat for a little too long so the plastic deformed a bit around the hole where the pin on the cover goes. This turned out to be a little problematic since the cover didn't want to come back on again. I had to scrape some plastic out from the hole to make it a little bit bigger.

The last step is to wrap the cable around the pins. This way it is protected in case you would pull on the cable. Put the cover back on and then put the foam pads back on. By this time you have probably forgotten which is right and which is left, but don't worry. It doesn't really matter, just run some stereo channel test track and you can easily figure it out. I used this track on YouTube. Then just push the speakers back in place on the frame you are done.

Result.

Hopefully this will allow me to use these fantastic headphones for another year or two. Sure, they are no hifi headphones but considering how cheap and portable they are amazing. Perfect for when you are out taking a walk, running, or training in the gym. Heck, I actually think they sound better than most other headphones that I have listened to it the same price range.

Estimated time: 10 minutes
Estimated cost: ~40SEK / ~$4.5 / ~€4 / ~£3
Difficulty: Basic
Tools needed: Soldering iron, flat head screwdriver or other pointy object

One year later...

As it turns out it is one year since I last wrote something on this blog. On year may not seem so long for some of you out there and I can totally understand that. Even when I was in school, one year would just fly by with only a few major happenings throughout the year. This past year though, has been something absolutely incredible.In this post I will do my best to sum up the year that has passed but I will also tell you a bit about my future. So, let's begin where we left it last time...

My last post was about the AKG K490NC headphones. I didn't buy them just because I wanted a new pair of headphones but because I had been accepted to the Global Active Programme, previously known as Learning School. I will not go to much in depth about what the actual programme was or what kind of work I did since it isn't really relevant for an audio blog. GAP meant that I would be travelling around the world for a year, and I couldn't bring my Denon headphones and my Koss Porta Pro aren't really suited for use in airplanes, buses and so on. So therefore I invested in a pair of noise-cancelling headphones.

My travels started in Scotland, where I visited Glasgow, Edinburgh, and Aberdeen along with two of the people I would be travelling for the year. We then continued up to the Shetland Islands where we were based at a high school doing various kinds of voluntary work. Then during autumn break we headed off to Italy for a short holiday. We visited Rome, Florence and Venice. After that we flew to Germany where we visited a high school in a small town, not much bigger than where I grew up. In the middle of our stay in Germany I got invited to go on a trip to Japan and of course I could not resist that so I spent almost two weeks over in Asia. I came back for one last week in Germany before heading home to my old school for a month before Christmas break.

I did a few audio-related things during this part of the trip, beginning with visiting the Mareel arts & cinema center in Shetland Islands. It's a modern top-quality music venue that also has cinemas, recording studios, and so on. We were given a guided tour by one of the employees and he showed us around the studio, the radio-room, the projector-rooms in the cinemas, and so on. It was a really fascinating place and a really valuable resource for the people living on the islands. During my stay in Shetland I was also lucky to see The Revellers live (a local folk rock band, they're good!).  In Italy it was much less informal. There I saw lots of street musicians and one night in Rome I ended up with some strangers rehearsing for a ukulele gig. A Swedish girl and an Italian guy playing ukulele and the singer was a Russian girl. Amazing people and amazing music led to a really good night. Germany, Japan and Sweden didn't include anything specific that I can think of.

The next part of the trip, the longer part, started on the 20th of January when I flew to America. Here we met up with a new member of the group. We had ten days of holidays before school started so we visited Philadelphia, Washington DC, and New York. It was very cold but nevertheless we had a good time. The school we visited in the US was about 45 minutes drive outside of New York and it was really interesting seeing bits of the American high school life with my own eyes. When our stay there was over we continued on towards New Zealand, with a one-day stopover in Los Angeles and two days in Fiji. In New Zealand we were in Christchurch most of the time working at an all boys high school and we also did a couple of trips to various places around the south island, including Fox Glacier. Our next stop was Canberra, the capitol of Australia. It wasn't quite what I had imagined Australia to be like but I still enjoyed it very much and the school we were at was really interesting. The last two weeks in Australia we had easter holidays so some of us spent part of the first week hiking in the Snowy Mountains and then for the remainder of the holidays we went to the south coast and then Sydney. Sydney was incredible, probably my favourite city on earth. There were great street musicians, we were even lucky enough to see Winterbourne, check them out!

As you probably know, the great Opera House is in Sydney. I had a brief look at the concerts that would be on during our stay in Sydney. There was one with Jeff Beck and another with Iron & Wine. I had no idea who either of them were, although I guess I should know who Jeff Beck is since he is kind of famous. Me and my friend went to the ticket office to see if there were any tickets left to either of the shows. There were only a few tickets left for Jeff Beck and it was the row in the very back of the chamber and it was quite pricey so we rejected it. However there were quite good tickets left for Iron & Wine so we decided to go with that. I think each ticket was about 80AUD, which isn't too bad for a concert in the Sydney Opera House. The concert was absolutely amazing, great music, great musicians and the sound and acoustics was mindblowing. I couldn't take any photos with my camera in there but I did film the last song of the concert with my phone, I could upload that to YouTube later on.

Sydney Opera House

The rest of the trip didn't include any audio-related events but after Sydney we flew to Cape Town, South Africa, and stayed there for five weeks. After that we had a one day stop over in Dubai, a week of free time in Prague, three weeks of work and conference in south-eastern Czech Republic and then before going back home again on the second of July I spent three days in Prague to wind down a bit.




Since I came home I have mostly been at home. A day or two every now and then working at the summer house and a couple of days visiting friends. Two weeks after I came home I got the results for my university applications. I don't know if I have mentioned it here on the blog before but my plan was to get a master of science degree in media technology at Luleå University in northern Sweden. Last year the programme got cancelled because of too few applicants. I decided I wanted to try to apply again but this year they had cancelled it before the applications started. I hadn't really thought of any other options. Of course there was the option of studying in Stockholm, but accommodation would be way too expensive there. I searched around a bit and found two other universities offering the same programme, one in Norrköping and one in Karlskrona. I decided to apply to Norrköping and at the very moment I'm sitting in my new room in Norrköping. I am sharing a three room apartment with two other guys and I just moved in today. I couldn't bring my big speakers or the subwoofers so right now I only have the Mar-Kel70 and my Denon headphones. There are not many options for speaker placement in my thirteen square meter room so I'll have to be happy with the only possible way, one meter apart and on top of a bookshelf. The bass is quite boomy but I'm planning on experimenting with the MiniDSP some day the EQ the worst peaks. The school starts on Tuesday with a two week long introduction course in mathematics. The first year will mostly be mathematics, physics and other "engineering" courses. First in my second and third year will I start with the more media-specific courses.

A package from Thomann arrived

A package from Thomann arrived yesterday. As usual it was five time bigger than needed and so it was stuffed with those huge bubble wrap things. Great, now I have another 15m of it.

The package contained a Behringer iNuke NU6000 and a microphone stand. I unpacked the Behringer yesterday and put it in the shelf but I haven't gotten the MiniDSP plugin yet so there's no need to hook it up yet. I tried the microphone stand though and I did a quick measurement in REW at listening position. Unfortunately I forgot to save it but it looked quite similar to the measurement I did before. Above 400Hz it is acceptable but below ~200-250Hz it goes all crazy. Hopefully I'll be able to fix most of it with the MiniDSP and subwoofers.

Quick measurement of in-room response

Here's a quick measurement I did yesterday. Since I haven't got any microphone stand I had to hold the mic in my hands, which could have had some impact on the measurement. It looks similar to what I have measured before. With my MiniDSP I will try to tame the huge peak in the bass but I don't think I will be able to do much about the dip at 100Hz because it seems to be some room cancellation. Same with the dip at 200Hz. But I don't think the dip at ~650Hz is a room cancellation, any clues to what it may be?

MiniDSP and UMIK-1 coming!

Today I just ordered a MiniDSP 2x4 and a UMIK-1. I have decided to return my Behringer iNuke NU6000DSP and get a non-dsp verison instead. This way I save about 500SEK. Hopefully I'll be able to sell my Reckhorn S-1 for ~600SEK and my Radioshack digital SPL meter for ~300. This way one can say I got the MiniDSP and UMIK for free. I have no idea when the stuff will arrive, but hopefully within a week or two (it's being shipped from Hongkong).

I'll be away for a couple of days now for a school trip to Slovenia, visiting the wonderful town of Maribor.

One year celebration!

Today the blog has been up for a year! Lots of things has been done in this year and I'll list some of them below.

• dMar-Kel70T
• HAD Oy
• Five O2+Odac combos
• Lots of new audio equipment
• Reaching 16000+ pageviews

What started out as a blog dedicated to music quickly broadened into a blog covering audio gear and DIY as well. I have documented my school project work here at the blog, which gave my project work the highest grade.  I have built an O2+ODAC amplifier/dac combo for myself and I have sold four as well. The profit has gone to buying my own soldering equipment and tools instead of borrowing from a friend.

What will come in the next year is unsure. I will finish the step-by-step O2 construction guide as soon as I find time. I will also write more about my stereo setup, which has now turned into a 2.2 stereo system. I will try to take more in-room measurements. After the summer I will either travel around the world in a project called Learning School or I will study at university somewhere in Sweden, probably master of science in engineering in the field of media technology.

School project exhibition tomorrow

Tomorrow is the day when all third year high school students will show off their projects at an exhibition in the city centre. I will bring most of my stuff with me there. Speakers, amplifier, cables, computer, two monitors, camera and some other stuff, like a subwoofer driver, 41Hz amplifier board and so on. I have already started packing some of the small stuff, but I'll do the rest tomorrow morning. Since I don't have my driver's license yet and my parents are not home I will have a friend help me drive all the the stuff downtown. I'm really excited, I hope it will be a good day. I have made a playlist with lots of different songs and I have made picture slideshows of my DIY work (kind of all pictures that are here on the blog).

I was planning to start writing part #1 of the step-by-step construction guide today but unfortunately I ran out of time. But here's a sneak peek ;)

As a little side note. I will be building two more amplifiers in the coming weeks. One is already sold and I'm hoping to sell the other as soon as possible too. If you're in Sweden and you want a O2+Odac combo, don't hesitate to send me a message!

Dead memory card, again...

I was filming my speakers playing music two days ago. Everything went fine except when I connected the memory card to my PC it was dead. Just like before, there was no way to reach it. The camera didn't read it either. I lost several hundred pictures and the videos I had filmed. I have contacted amazon and they'll give me a full refund this time instead of sending me a new card. So I bought two new 8GB cards instead from swedish Dustinhome, they should arrive on tuesday I guess. Then I will take some pictures of my Nexus phone and maybe try filming some again.

Meanwhile, take a listen to the album Brother Where You Bound by Supertramp. Excellent audio quality and nice music as well.

A bit on the "calm" side recently...

There hasn't been many posts recently, I know. But things happen in life so I simply don't have time to make blog posts.

A short summary of things I should make blog posts about but haven't had time for. It will come though, eventually.

• LG Nexus 4 smartphone short review
• Koss Porta Pro headphone review
• Swapping powersupply in my computer to a more silent one
• Room measurements with REW and an Audyssey mic
• I have gotten a job
• Thinking of finishing one of my 41Hz amplifiers, most likely the AMP10-Basic
• Plans of building a measuring mic based on the Panasonic WM-61A

As you see in the list there's a quite time-consuming point in there. The one about the job. I have gotten a job at a company that books travels for people. Not holiday travels but more like to and from hospitals and such. At the moment I'm just learning the job, and it will be that way for a month or so, but afterwards I'll start working weekends and evenings. This steals away much of my time.

Another time consuming thing is the whole workout and fitness stuff. Working out 5-6 days a week and making sure I get enough sleep also takes away much of my free time. Luckily I have fewer classes at school this semester so there's hopefully less schoolwork now. I still have six physics classes per week which will require some home studying, writing reports and essays and such.

10000+ pageviews!

This blog has now been visited over 10000 times, since I started it back in april. A very nice milestone and I hope to achieve 20000 pageviews in not too long.

A little cabin I photographed last thursday when I was snowmobiling up on the mountains in Vemdalen

Oops! Blew the last functioning tweeter

I was playing some fairly dynamic tracks at fairly loud levels (I hit 107dB at listening position about 3m from the speakers). During one of the crescendos of the track Stimela (Coal Train) with Hugh Masekela I heard some distortion noise and then the highs went away completely. If the speakers have a sensitivity of 89dB/1W as the label says and the power handling is 70 watts I must have been using a bit more than that, considering I would need ~63 watts to play 107dB at one meter distance and I was measuring the SPL about 3m away. And since only one tweeter was playing I guess it was being loaded unproperly and therefore couldn't handle as much either.

Well, that's the first time in my life I've blown a tweeter. Interesting.

Temporary speakers, with bad tweeters

Since I've stripped one of my Mar-Kel70 speakers I needed a new set to use while I finish my Mar-Kel70T. I decided to grab some old speakers I found in the cellar, some Zachry dipole/bipole (I still don't know the difference! :P). But at the first song I realise something is wrong. The cymbals and high frequency stuff only comes from the right speaker. With some help from my ears I find that three of four tweeters appear to be broken. I opened one of the speakers to see if there were any loose cables but everything seemed OK to me.

This is what they look like, another pair of drivers on the other side too.

A pretty simple filter, indeed!

Pictures of the CSS EL70eN

Here's some pictures of my CSS EL70eN, modified by David Dlugos at http://www.planet10-hifi.com/

5000 pageviews!

Seems like my blog just passed 5000 pageviews. Keep it going and please comment :)

By the way, I was supposed to continue building on my speakers today but I forgot it and went photographing instead. This is what the sunset looked like (took me a while to find out how to get the picture right so by then half of the magic was gone).

Click to enlarge the picture

The speakers have finally arrived!

Dad came home with the speakers today. Three packages in total. One long, heavy one probably just containing lots of the 18mm birch plywood (I guess all the parts for the Oy). One slightly smaller and much lighter package containing the stuff for the Mar-Kel70T which Ingvar was so nice to cut for free. It also contained filter components, binding posts and panels, some damping material, glue, cables (the cables to the tweeters were missing but Ingvar will send them with the drivers later), screws and some other stuff. The smallest box was very light and it seems like it contains damping material only for the Oy.

Click for a larger picture

Tomorrow I will start building the Mar-Kel70T speakers, hopefully everything goes as planned.
Everything will be documented thoroughly since I'm planning on using some of it for a school work.

The speakers have arrived! (Almost...)

Ingvar e-mailed me today saying that the speakers had arrived at my dad's job in town. Will be getting them home tomorrow.

I'll start with building the Mar-Kel70T since I have drivers for them, and use them until I get the drivers for the HAD OY (as they're so beautifully named :P)

The waiting for delivery is finally coming to an end soon

I got a message from Ingvar yesterday. He told me that Morel had lost the other driver shipment too so it will take another while until I can get my drivers. But he said that he could send me all the other stuff so I could start assembling the cabinets and have that done when the drivers arrive. That's a very good idea and he'd pay the extra shipping costs that would lead to.

This morning I started thinking of assembling the Mar-Kel70T that Ingvar has cut panels for. The issue of damping material came up in my head. I have CSS Ultratouch in my current cabinets that could be salvaged but that's not the best and easiest way of doing it. So before heading to school this morning I sent an email to Ingvar and asked him if it was OK if I bought some extra damping material for the Mar-Kel70T. He said that it was OK since he didn't have time to ship the stuff yesterday and would do it tomorrow instead and he also said he would give it to me for free since it was so little. He's a nice guy!

So hopefully I'll have the stuff on friday, else I'll have them at my dad's job on monday and here at home on tuesday evening.

Speaker cables

Since I'm not allowed to reproduce any of the content I'll just link to the website instead - http://www.roger-russell.com/wire/wire.htm

It's about speaker cables and how many bullshit products there are out there. I totally agree with the author.

Personally I'm using Supra Classic 4.0 speaker cables, but I got them for free when buying an amplifier and they are flexible and nice to use so that's why I'm still using them. I have compared them to some expensive Van Den Hul cables (borrowed from a hifi store) and some CAT5-cable. I didn't hear any difference between any of them, to be honest.

Waiting for delivery...

When I spoke to Ingvar (the guy I have ordered speakers from) last week he said he'd send the stuff on monday this week (that was yesterday). I emailed him today to see if he had sent the stuff and he replied that a delivery of filter components and drivers had gone astray so he had to wait for it to arrive before he could send the stuff to me. So while I'm waiting for the stuff to come I took this beautiful picture from my balcony. The winter is coming :)

Click for a bigger picture