Monday, 17 October 2011

Musical Tastes

Some popular comments on Youtube:

1. Bieber is horrible, let's go dislike his videos !!1 <3
2. Why can't artistes these days be more original? This guy should be way more famous than Jonas Brothers!!!1
3. If this song was a carrot, it'd be a good carrot.

The general consensus is that modern pop artistes lack originality. And to a certain extent, I agree.

Compare these two videos:


Both videos feature artistes who were megahits in their 'era'. Some artistes like Justin Bieber, Miley Cyrus, Lil Wayne, T-Pain, aren't exactly liked by many. Pretty much all their songs revolve around money, drugs, women, etc but their individual talents made the song a little more unique than it was back in MJ's time. 

Compare these two videos:


Lots of modern songs re-use the same "chord progressions" in older songs. Nicki Minaj's Check it Out's tune is quite similar to the song Video Killed The Radio Star. End of Fashion's O Yeah is a straight up rip-off of The Pixies' Where Is My Mind (Fight Club 1999). For those who didn't know, Video Killed The Radio Star's music video was the first music video aired on MTV. 

This is just my personal opinion, but I think most mainstream hip-hop, RnB, rap singers are pretty unimaginative. While most songs (no matter the genre) focus on the same themes, I can't imagine a whole library of songs of the afore mentioned genre. Beats like ATCQ's Can I Kick It are hard to come by...
I suppose the main reason why artistes like Justin Bieber, Pitbull, T-Pain, etc are so popular is because of their "jam" factor. Me, I prefer songs that flow. But whatever others' musical tastes are, we should respect their opinions and stop all the copypasta nonsense on Youtube. 


Tuesday, 4 October 2011



I can think of many everyday items that need burn-in. In most cases, burn-in is just the process of getting used to the item. In some cases, the evidence of burn-in is quite obvious. Shoes getting more comfortable over time, leather wallets shaping up over time are just two very obvious examples. 

Back when I was younger I used to play with these Tamiya toy cars. One of my classmates told me of a trick that would "increase my car's top speed". What I had to do was keep the car running till the rechargeable batteries went flat. He called this "seasoning the engine".

Did the top speed of the toy car actually improve? At that time I thought it did, ever so slightly. 

How is any of this related to audio?

As of late, many lower end headphone reviews go like this: "these headphones sound like junk but run some music through them for 100-1000 hours and they'll change into terrific headphones worth twice as their selling price". How much truth is there in that statement?

First let me just say I'm not a huge believer of burning-in headphones. I think headphones sound the best the first few hours they're out of the box. The first thing I do after unboxing headphones is put them on my head and run some tracks through them. Some take this burn-in period so seriously that they immediately put their headphones through 100 hours of continuous pink noise. 

Testing burn-in

It is very difficult, if not impossible, to find out if burn-in significantly alters the sound of the headphones. This is due to the fact that to conduct a fair experiment, identical headphones are needed. Two headphone drivers are never identical.

Tyll Hertsens of Innerfidelity conducted an experiment. He put one pair of AKG K701 through roughly 1000 hours of burn-in and a new out of the box AKG Q701. He could tell apart the AKG K701 from the AKG Q701 in an improvised blind test but commented that the differences were very subtleMany burn-in skeptics argued that the experiment only showed that he could tell the two headphones apart and they are absolutely right. Unless they can make two absolutely identical headphones, then it's impossible to test burn-in. 

The point I'm trying to drive home here is that even if burn-in did alter the headphone's performance, the differences between new and headphones that have been burn-in'd are not night and day.

3 crazy stories about burn-in

1. USB cables sound better after hundreds of hours of transferring data.
2. Speaker cables' sonic characteristics change significantly over time.
3. Rechargeable batteries makes the amplifiers sound better after a few charging cycles.

Orly. Apparently some cables also need a settle down time after you move it. I have to admit I have not had much experience with speaker cables, but most audiophile claims are based on pseudoscience. 

Giant Killer headphones

Many reviewers look around for "giant killer" headphones. $30 headphones that can trump $150 headphones, $50 headphones that sound a little like flagship headphones, you get the idea. These reviewers then put a disclaimer note in their review: these need 100 hours of burn-in.

Those who don't have access to an audio shop to compare the cheaper headphones and the more expensive ones side by side get excited and sucked into the hype surrounding these headphones. They pull the trigger, buy the $30 headphones, find out that the headphones sound about as good as any other $30 headphone, question the reviewer and the reviewer tells them they need to put them through hundreds of hours of burn-in, or he tells them that they're an acquired taste, etc. 

I'm not saying that all giant-killer flavour of the month headphones blow, some like the Superlux line-up are pretty decent for their price. The Fostex T50RP and Grado SR60 are sub-100 headphones that have a lot of potential but the idea that headphones sound WAY more different after 100 hours of pink noise than when they were first unboxed is just the plain bull- that reviewers use to cover their butts when the angry mob starts gathering around. 

It would certainly be very interesting to conduct an experiment with two pairs of headphones that supposedly need 100 hours of burn-in to sound right. Run a pair through some pink noise and leave the other as it is. Afterwards, get someone to do a sighted listening test, have them identify which is the pair that is burned-in and then conduct a blind test, to see if they can identify which headphone is stock and which has been burned-in. If the difference is night and day, surely they can tell the two headphones apart easily.

File:Bathtub curve.svg

Protect your hearing, protect your headphones. Although I'm not a hardcore believer of headphone burn-in, it is always good to start off with a low volume level and then slowly increase it up to whatever you're comfortable with. Suddenly playing very loud music on a very old or unused pair of headphones might overwhelm the diaphragm. 

This form of safety burn-in is exercised in the industry.
Image on the right is the bathtub curve used in reliability engineering.

Monday, 3 October 2011

Now Playing

a short playlist of hip-hop songs.

  1. A Tribe Called Quest - Can I Kick It
  2. Timbaland - The Way I Are
  3. Madcon - Beggin
  4. Keri Hilson - Knock You Down
  5. David Guetta - Memories
  6. Kid Cudi - Day 'N' Nite 
  7. Kid Cudi - Erase Me
  8. Flo Rida - Club Can't Handle Me
220px-Step_Up_3D_Soundtrack.jpg (220×220)

Movie Soundtracks

The Step Up 3D soundtrack is pretty good. It sucks that most hip-hop/pop songs sound muffled though, including the tracks on Step Up 3D. The movie's pretty cool even though it's been drifting away from it's roots (Step Up 1, Step Up 2) and becoming more "mainstream".

Generation Kill is a very interesting movie series. The story is based on a reporter's account of his time with the Marines in the 2003 Iraq invasion. The acting is great. The soundtrack is pretty unique. The Marines are singing and rapping songs while they roll in their Humvees. It's definitely not the usual Hollywood action movie. 

Some good movie soundtracks...


Saturday, 1 October 2011

Playing music on your PC Part 2 (Amplifiers)

Amplifiers and external DAC

Amplifier: The primary function of an amplifier is to provide that extra voltage or current needed to drive your headphones. You should think about getting an amplifier when you need to turn up the volume on your music player more than 70% or if you have headphones that have really low impedance (<32ohms) or really high impedance (>100 ohms). 

DAC: Short for Digital to Analog Converter. What is does it change the bits of data in your PC to analog data (voltage, current, electric charge). Most PCs do not have dedicated sound cards. They use codecs. For more info on codecs check out this wiki

Output Impedance

Some amplifiers in the market measure very poorly. One very important specification you should look out for when looking for amps, is the amp's output impedance. The amplifier's output impedance should roughly be 1/8 of the impedance of your headphones. Some headphone amplifiers or headphone outs on amplifiers have very high output impedance. This may cause damping issues. 

The impedance value of headphones changes with frequency. The image on the right shows the impedance versus frequency graph of two headphones. 

If the output impedance of the amplifier is not close to zero, the voltage supplied to the headphone will also vary with different frequencies. This will in turn affect the frequency response of the headphone. It may smooth out the highs, etc. Under-damping might also cause the bass to sound boomy. If you want to keep the sound faithful to the frequency response graph, then you need an amplifier that has almost 0 output impedance. 

Unfortunately not many manufacturers publish the output impedance of the amplifier. 

Myth: Buying the highest impedance version of a certain headphone will reduce the noise floor and prevent the frequency response from changing. 

Explanation: Truthfully, I'm not too sure about the noise floor. I can't really discern any differences between a 250 ohm DT770 and 80 ohm DT770. Regarding the frequency response, like what I said above, it is best to get an amplifier with an output impedance of close to zero so that the headphones will remain faithful to it's FR curve at all frequencies*. A higher headphone impedance will allow for a higher amplifier output impedance though, so if you have an amp with a high output impedance (older amps) go for the highest they have to offer.

*Some of you readers might find all this a little contradicting. All this talk about remaining faithful to FR curve and equalising... Just to clarify, staying faithful to the FR curve is important because I'm an equaliser believer. If my headphones aren't true to their curves (colouration), then if I remove a component from my set-up that is causing the colouration, my EQ settings will be screwed. 

Onboard Audio

Plugging in an amplifier will not make the music sound any better if your onboard audio sounds like poop. The same goes for music players. Connecting an amplifier to a PSP will not make the music sound more refined. Amplifiers are for driving your headphones if you need to turn the volume up to get decent volume. To improve the quality of music reproduction, you need to get a better DAC. 

Older PCs definitely need an external sound card but newer PCs do not sound too bad. There's really no way to replace the onboard audio that is soldered onto your motherboard (in the case of most laptops) so getting an external DAC that connects via USB is the best way to bypass the onboard audio. 

This is a very subjective matter though. A $300 DAC will not dramatically make your music that much better. If you're the average joe listener who multitasks, you might not be able to hear the difference between laptop audio and an external DAC. But if you close your eyes, you'll definitely notice the differences. One of the biggest differences you'll notice between a good DAC and onboard audio is the noise level.  

In my (very little) experience, my laptop's onboard audio sounds congested and bloated at times. I had to use the equaliser at times to compensate for the bad sound quality. Even if you have very good headphones, a bad DAC and/or amplifier will ruin the set-up. There is a simple way to ensure that you get the best out of your PC. This method is done to achieve bit-perfect playback.

My belief is that try to keep everything lower in the chain as neutral as possible. Start with any headphone of choice, pick a decent DAC and an amplifier that has a neutral sound signature. The only thing to mess with then is the headphone itself and the EQ.

For those on Windows 7

Get foobar2000 if you haven't. 

Just installing foobar doesn't make the music sound any better but you can achieve bit-perfect playback by installing a simple plugin called WASAPI. This plugin prevents Windows from altering the sound and also disables all Windows beeps and alerts. If you've got foobar2000 on, you might not be able to hear music from Youtube music videos though. 

For those on Windows XP

Get ASIO4all here.

Fiio E7

The Fiio E7 is an amplifier and a DAC in one. It is roughly the size of an iPhone. I think Fiio did a great job with this product. It has a plexiglass cover on top, a display much like the one on the Sansa Clip+, a digital volume control, 2 headphone outputs, 1 USB input and 1 line input. 

The battery life on the Fiio E7 is rated at 80 hours and you can charge via USB and use it to replace your onboard audio at the same time. It can also drive my low impedance headphones (HD438 and SR60) to insane levels. It is also a fairly transparent amp which will make your headphone sound faithful to it's FR response curve due to it's very low output impedance. There are also reports from Fiio that 
                                                                             you can use the E7 with the OTG usb feature in some phones.

Fiio E10 

Unlike the Fiio E7, the E10 does not have a battery. It does have a better amplifier section. I like the volume pot and the overall look of the product. It's very sleek and is a nice addition to the Fiio line up. It is priced slightly lower than the E7.

I personally have not tried the E10 but according to the review on headfonia, the E10 has a lush midrange and it makes the bass sounds more full. The E10 also supports line out, coax and usb. It also has two gain options, high or low, depending on the headphones you are using. Very promising product. 

(photo credits to Headfonia)



Friday, 30 September 2011

Playing music on your PC Part 1

This is my take on the whole FLAC vs mp3 controversy.

How do you check if a file is truly lossless?

From what I understand, one of the ways mp3 files are compressed from FLAC or WAV files is by cutting out the top frequencies in the spectrum. This can be seen on a Spectro* chart below. The top image is a FLAC version of the file. The peaks reach the top of the spectrum. The lower image is the same file converted to 320kbps mp3. The peaks in the second image look "chopped off". 

Track used was The Killers - Change Your Mind

Spectro is a useful tool for checking whether the file is a true lossless file or if it's a lossy file converted to lossless. The encoder used is displayed on the bottom left corner. You can get Spectro here.  It's free.

Anyway let's get back to the topic. According to the diagrams, lossless files have their high frequencies chopped off. In usual recordings the instrument that produces that high of a frequency is the cymbal. Unless you are very sensitive to high frequencies or have very good headphones and equipment that reproduce high frequencies very well, the difference between high bitrate lossy and lossless files are really tiny.

Downloading music from file sharing sites

Some of us are guilty of downloading music files through less than legal channels on the internet. Sometimes we notice a very significant between those and files obtained through legal channels. If both files have comparable bitrates, then there's a high chance that somewhere along the converting process the fellow accidentally introduced some noise into the file. I don't know how this happens but I have experienced this before. 

Blind Testing

Why? Because sighted listening is heavily biased. 

Test it out yourself
  1. Download Foobar2000. It's a great music player that uses a lot less power than iTunes. 
  2. Download the Foobar2000 ABX plugin here.
  3. Convert some lossless files (FLAC/WAV) to high bitrate lossy (MP3/AAC/OGG)
  4. Run the test.
Video tutorial (not mine)

If you can get a good result without guessing, give yourself a pat on the back.

Is a high bitrate mp3 really that important?

There's a phrase that is commonly said in audio forums; you need to have everything in 320kbps or FLAC if possible. If you have a very good headphone rig and you are the kind of person who does critical listening, then this is true. If you are that person, I don't know why you're reading my articles.

Anyways, with a very good system, the differences between a lossy and lossless sample is more apparent. But they skipped a huge step. Just having a lossless file does not ensure a high quality sounding track.  The mastering or recording of the track is more important than the bitrate of the file. Unfortunately, whether the mastering is good or bad, it's out of your hands. Mastering is entirely up to the engineers behind the album.

Some blow so much money into audiophile recordings only to find out that they're just fooling themselves. If you like listening to mainstream songs like Backstreet Boys,  Pitbull, etc, don't force yourself into buying audiophile tracks.

Building a system

This is how you should build your headphone rig, imo. Invest as much as you can into headphones. Use as much as you have left into an amplifier if you have power hungry and inefficient headphones (you can use stereo receivers instead), if not, get a decent DAC if you are still using your PC's onboard audio. Lastly spend some money on CDs or just download them off the internet and save the rest for a rainy day.

If you are on a tight budget, say.. $50, spend all of it on headphones. There are a couple of cheaper sub-100 headphones that are easy to drive and sound decent. Amplifiers come second. 

I find it hard to distinguish 400kbps AAC or 320kbps mp3 from FLAC but that doesn't stop me from loading lossless tracks on to my portable media player (Sansa Clip+). Sometimes it doesn't matter if the difference you hear between two things are real or imagined. If you think FLAC sounds better in a sighted listening test but you can't differentiate mp3 and FLAC in the Foobar2000 ABX test, then by all means do whatever makes you happy.

Thursday, 29 September 2011

Sennheiser HD438 Modifications (work in progress)

The Sennheiser HD 4X8 series are very similar in design. The internals of the HD418, 428, 438 and 448 are roughly 90% similar. The only differences are the drivers, the detachable cable (HD438). Wiring and everything should be the same on all the HD4X8 models.

All you need for the following mods are commonly found household materials. Disclaimer: Don't blame me if you screw something up while modding your 'phones. Also, your mileage may vary with these mods. Everyone has got different tastes but the good thing is that none of these mods are irreversible.

Quality vs Quantity

Bass quantity and bass quality are two different things. An increase in bass quantity will make your headphones sound a little boomy in the bass department. Bass quality depends on the headphones. Some headphones can reproduce bass that extends deep down in the frequency (20-50hz) without any problem. Some struggle to reproduce bass that low.

Examples: Denon D2000 vs Grado SR80, Ultrasone HFI-580 vs Sennheiser HD448

Most of the modifications that I will be sharing involves tweaking the bass on the Sennheiser HD438 by using different materials to mask the holes behind the drivers. This will affect the whole sound signature and the tone of the headphone. However, you cannot change the frequency response curve of the headphones without changing the drivers or adding filters.

You can experiment and come up with suitable configurations or "settings" that suit you best. 

Must-try mods will be marked with a 

HD438 internals

This is more or less what the HD438 will look like when you remove the ear pads. The yellow circles indicate where the screws are. You have to remove the screws to access the back of the driver chamber. 

The tricky part is that the screws are under the grey foam so you have to locate it with your finger, fit a screwdriver on that spot and start unscrewing. The grey foam will come off along with the screw. You will need a small philips screwdriver for this.

Removing the ear pads

Pinch at the yellow circle and pull it across the face of the driver in the direction of the red arrow. It takes quite a bit of force. Be firm. Don't go Kong on your headphones, you don't wanna have to end up paying 15 bucks for replacement pads.

1. Tape mod

If you feel the thin fabric on your ear pads vibrating against your ear and you want to remove that sensation, add some double sided tape as shown on the first image. Be careful not to cover too much of the grills.

2. Inverse ear pads mod 

As illustrated in the following picture.

Just reverse the ear pad and stick it together to the cup with double sided tape. This makes the HD438 supra-aural. I prefer using this mod when the weather is really warm. You can experiment with other ear pads from other headphones. Different ear pad shape and material results in a pretty large difference in sound.

3. No earpads 

Without the earpads and with the cups not touching the ear as illustrated above, you get the clearest sound. If you like the HD4X8s this way, I suggest getting some cheap ear pads that resemble quarter modded Grado comfies and stick them onto the cups. This setting is perfect for piano (imo) but doesn't really work well with club music and rock songs.

Edit: second thoughts --> I don't like them like this.

4. Dampen the inner cup surfaces

There isn't much space between the inner surface of the cups and the driver when you put everything back together. If you put too much blutack or plasticine on the surface, you might not be able to fit the driver back in properly.

If you like opening up your Senns to mess around with the internals and do some further tweaking, the bluetac might make it really difficult to pry the cup from the driver. I used a coin for this.

The blutack dampens the resonances in the cups to make the sound less muddy.

5. Dubstep mod 
Step 1: Remove the tape covering the 3 holes.
Step 2: Apply a thin layer of blutack on the inner surface of the cup to dampen resonances.
Step 3: Put everything back together. 

The back of the driver enclosure. The black tape is covering 3 holes. The black tape used here is semi-permeable and allows air through it. Uncover all three holes for maximum bass quantity.

This is the surface of the cup. 

Cover this area with a layer of blue tack. Make sure it is not too thick but don't spread it out too thin either. 

What I did was remove the small circuit board first so that I could apply some blue tack underneath it. This makes the thin wires less prone to breakage.

6. Bring out the highs 

with an equaliser.

Tune up the equaliser to +5db at 10kHz and the change should be gradual starting from 2kHz, so step the equaliser down by 1db as you go along. You should end up with a gradual slope as indicated on the right hand side of the image. If you want to be a little more adventurous, equalise the mids a little. What I did was +1db at 220Hz, +1 db at 311Hz, +2db at 440Hz and +2 db at 77Hz.
The increase in highs gives the impression of a clearer sound signature, at the cost of sibilance. Vocalists such as M. Shadows of Avenged Sevenfold sound a little sibilant after equalising but it's not too bad. I think this is a must-do for the HD438. Even if you're against equalising, try it out. You don't need a sophisticated equaliser program, the Foobar eq will do.

7. Neutralised HD438 (sorta) 

Things you need: 
1. Gauze or bandage (doesn't need to be new/clean).
2. Some blutack, putty or plasticine. 
3. Philips screwdriver and maybe a small coin to open up the cups.



As you can see from the image aboves, I applied some blutack around the 3 holes and then stuck some gauze on the blutack to act as the filter. Without any material/filter covering the holes, the bass will be overwhelming. I actually used the gauze I "tore off" my SR60. I suppose speaker cloth could work just as well. Extra porous bandages are good substitutes if you don't have any thin gauze.

I'm currently using this with the ear pads on and with the equaliser settings I posted above. After modding and applying the EQ, the same warm sound signature is retained but since the bass is leaner, highs are a little more prominent giving the impression of clarity. I think it sounds a lot cleaner. 

Currently listening to The Killers, Radiohead and other random songs on my Sansa Clip+ and E7. Love this set-up. 

By the way, the ear pads used is a huge determining factor of the overall sound signature. Some pads make these headphones sound very shrill and thin, some give the headphones warmth or a more full bodied sound.

Experiment with the holes. Use different materials. Instead of blue tack, use cloth, etc. Some configurations are really bad but the only way to find the type of sound that suits you best by trial and error.

My Current EQ settings for HD438

It's the one on the right. As you can see, the Equaliser settings are pretty huge. It goes up as far as +5db on some frequencies. I did this to make the headphones more detailed at low volume. The Equaliser I'm using is actually the ElectriQ Fosihfopit (free). It works great on Foobar.

Sennheiser HD438

Short story

My father bought me the HD438. My first headphone. I was going to get the HD418 which is about $100 here, but he insisted that we get something higher up the line so I settled with the HD438, which is about $130. A couple of months later I bought the SR60i. He was pretty down about it... When I hear others say how crappy the cheaper Sennheisers are, I get a little mad inside, lol. These headphones are very special to me. $130 is quite a lot to spend on a hobby, especially since I don't have a job and my dad only earns enough for us. I mean srsly, if you offered me the HD600 to trade for my HD438 I wouldn't. Or maybe I would. I'd sell them and use the money to get a new pair of HD438s, and then spend the rest on pizzas. Hue.

Moving on to the review...

The Bad

This headphone is always overlooked and under-recommended.

The word that has been going around in audiophile circles since forever is that anything that is flashy is Skullcandy and anything Skullcandy is bad. The Sennheiser HD438 have got chrome spokes that really make you stand out in the crowd. In my opinion, they look pretty sleek and certainly not as bad as Skullcandies which are just so gaudy. I have a classmate that thinks my HD438s look too plastic.
The build quality of the Sennheiser HD438 is decent but they cannot be thrown around. They are not collapsible so storing them in your bag might be a little difficult. 

The Ugly
Not for use in hot tropical climates, unless you are always in a controlled environment. The velour pads can make your ears really warm. Not for anal guys who love their headphones FR to be flat either. 
The Good
They are circumaural closed headphones. Most closed headphones do not leak as much sound out as open headphones, even if you turn the volume up. You can use most circumaural closed headphones in quiet public places, such as libraries, public transport, etc. Of course there are exceptions like some Denon headphones. 
Very little sound leakage also translates into good isolation from the outside world. However, there is an important difference between circumaural headphones and active noise cancelling headphones. Circumaural headphones do not use any special technology to block outside noise, they just cover your ears like ear muffs. Active noise cancelling headphones require batteries. The mechanism in the headphone will produce some sort of wave that cancels out noise coming from the outside world. I'm not really sure how this works but you can read up on it on wikipedia. The HD438s are circumaurals that do not block outside noise.


The Sennheiser HD438 is very comfortable. This can be attributed to it's lack of clamp force and velour pads. Those wearing glasses will have no problem living with the HD438. They're also perfect for watching movies. Those who love to headbang claim that the lack of clamping force is a problem, and they're right. It really depends on what you use them for.   

The HD438 has the trademark Sennheiser sound signature. Sennheiser headphones have a very dark character as opposed to some headphones which sound bright like Grado or Shure. The problem with bright headphones is that they're fatiguing (imo).
The packaging on the HD438 says that the headphone has enhanced bass. They do have good bass extension which is to say that they reach really low into the sub bass region (good for dubstep) but they lack the bass slam or impact (bad for dubstep, good for rock) compared to other headphones like Sony XB5/700.
In stock condition, these headphones are decent. They do not really do anything exceptionally well, like how the Grados excel at guitar and drums. A little EQing will bring out the best in these but for $80, they sound pretty good. I'm a big fan of equalisers btw.
There are tweaks that you can do to the Sennheiser HD438. More on this in the next article. I will put up some images of the Sennheiser HD438 but they are not in stock condition, I've made a pretty huge cosmetic "upgrade".