Cocktail thermodynamics

I enjoy the occasional cocktail. My colleague Chris enjoys, makes and criticises cocktails. Door 34 in Bath makes really excellent cocktails. I have been known to indulge in a little thermodynamics; it was inevitable that one day these positions would collide in “the Boston Shaker Problem”. Chris swore on his reputation as a mixologist that:

  1. When cocktail ingredients are shaken with ice in a Boston shaker, the temperature drops to well below 0°C
  2. Using more ice results in less dilution
  3. Ice used in cocktail bars has been draining on the side, and is not below 0°C

This flies in the face of what we think we know about ice and water at atmospheric pressure, namely that:

  • If you attempt to raise the temperature of ice above 0°C, it will melt.
  • If you attempt to lower the temperature of water to below 0°C, it will freeze.
  • If you have a system of ice in contact with water, it will tend to equilibrate at 0°C, and resist changes to the temperature by melting and freezing as necessary.

If the ice starts at zero, and the other ingredients start above zero, where is the mechanism to lower the overall temperature? Seemingly the only available way is to take heat energy into the solid ice phase and melt. This isn’t going to work with non-melting ice cubes. It also doesn’t explain why we don’t hit our usual equilibrium temperature of 0°C.

The second part is just as confusing: there is a fixed amount of energy required to convert water between solid and liquid phases at a given temperature and pressure. This is known as the latent heat of fusion, \Delta H. This is an amount of energy per mass of water. As the total energy needed to cool your drink is fixed, the amount of ice that needs to be melted should also be fixed. (It’s not quite proportional, as you will need a little bit of extra melting to cool the extra water – and so on.) How does a greater bulk of ice help?
At this point we had a few ideas,  but turned to the internet for help – surely this is a well-known system? We did find an article at Cooking Matters, who not only hit on a good theory, but actually tested the effect with a thermocouple on their cocktail shaker. (It’s a pretty entertaining blog, if you’re interested in kitchen centrifuges and lobster-killing technique.) The key point is this: the system in a Boston shaker is not an ice-water equilibrium. The alcohol shifts the equilibrium to a lower temperature. Why? Entropy.

Door 34 asked for a mathematical description of the effect, and we gave them this:

\displaystyle 0 \geq \sum\limits_\textrm{mixer}^\textrm{ice} \left[\Delta U + \int mC_p \textrm{d}T \right] - \int S_\textrm{mixing} \textrm{d}T

It is worth giving a brief breakdown. The right-hand side of the equation is equal to a change in the Gibb’s free energy of the system. For a spontaneous process, this must be negative; at equilibrium it will equal zero (hence the ≥  sign.)  I’ve neglected the pressure-volume work as it is not expected to significantly contribute; strictly speaking there will be a little work associated with volume change as ice has higher specific volume than water, and water/ethanol mixtures have a lower specific volume than the sum of components.  I’ve also been a bit cheeky here in separating the vibrational contribution from the internal energy (strictly U should be U_{\textrm{pot}} or something.) This is to draw attention to Kirchoff-equation related goodness; the difference in heat capacities determines how much ice must melt. As the ice melts, \Delta U increases as water is a higher energy state than ice. Assuming no heat input, the enthalpy (in square brackets) must be conserved, and so the heat capacity C_p is integrated over a negative temperature difference to compensate; the temperature drops. This is driven by the entropy term on the far-right; as long as more entropy can be gained by melting ice to mix water and alcohol, the ice will continue to melt, dropping the temperature further, and well below 0°C. (Note that T in the equation is relative to absolute zero, and will never be negative.)

A problem remains– why does more ice mean less dilution? According to this, the equilibrium amount of melting is pretty much fixed. If anything, adding more ice should drive entropy in the direction of more melting. My best guess is that this is to do with the speed of the operation; a Boston shaker isn’t quite an isolated system. The longer it takes to reach equilibrium, the more heat will have entered the system and the “wetter” that equilibrium will be. This seems to agree with the account of mixologists, that shaking with more ice is a quicker experience that “feels” different. Still, I’m left feeling that this system isn’t quite solved yet…

Not included in Best Records of 2012

Alt-J — An Awesome Wave

It’s rare for me to give up on an album half way. If something truly remarkable happens in the second half, I am very sorry. What was wrong with this record? Well, I was put onto it by the rave reviews and awards it received from numerous journalists and industry groups, praising it as some remarkable breakthrough in artistic pop music. One particularly hyperbolic reviewer described it as:

… a stunning and encompassing affair of both innovative and electrifying musicianship and exemplary song writing. Comparing Alt-J to contemporary artists or listing their influences is almost pointless. Each song blurs, stutters, and explodes across a tide of instruments and ideas, fresh and addictive.

To suggest that this is true of An Awesome Wave is frankly offensive to countless other musicians. To draw a few obvious examples, Everything Everything are touring right now. This record won the Mercury Prize over Plan B (see my earlier review) and Field Music. Kid A was released over ten years ago. It’s not that An Awesome Wave is a terrible record, but there is nothing about it to suggest that it deserves a place alongside music which is better crafted, less contrived and more moving. If you are a music reviewer and you gave this record 8/10 or more, please go to Camden Lock with a placard and find someone who will trade you their spare copy of Amnesiac for your job. It would be better for everyone.

 

The absolute best records of 2012 (based on a very limited sample (Part II))

Katatonia — Dead End Kings (Deluxe Edition)

Dead End Kings (artwork)

Melodic doom metal. Maybe there’s something intimidating about the name? I really don’t understand why this band and genre don’t enjoy a much wider popularity. You get the power and darkness of metal in something much more accessible and more overtly ‘human’. Instead, people looking for this crossover seem to fall into Post-Hardcore and Emotional Hardcore, the brash punky cousins. I suspect a lot of people don’t know that they like Katatonia. In a word, Dead End Kings is “mature”; the lyrics still touch on cliches but are generally more sophisticated than their earlier work, and there is an air of subtlety and delicacy running over the whole record. It’s not very exciting, but it is quite nourishing; the folkish melodies and vocal ornaments really come through and supported by well-written vocal harmonies and strings. Dead End Kings is not too repetitive, not too exhausting; there is no attention-seeking virtuosity yet it never feels lazy. While not especially pioneering, this is a well-crafted piece of rich, accessible music. Recommended, with one caveat: you will need the deluxe edition. It includes a final acoustic track, The Act of Darkening, which winds down the album and sets a suitable mood for leaving the music behind. This track is essential — if you didn’t get it, you were ripped off. We are used to “bonus tracks” which ruin the structure of a record by running the ending into some lame demos and remixes. This is the opposite; it appears that the official main release was deliberately crippled. Not cool.

Behold The Arctopus — Horrorscension

horrorscension

There are really two reviews here: one for those who don’t know about Behold The Arctopus and one for those who do.

Behold The Arctopus play instrumental avant-garde metal, chanelling the best of 20th-century art music into distorted guitars and furious drumming. If you hate any of those things, this is probably not a band you will get along with. My recommendation is that you get into 20th-century art music because it is awesome. They have a wonderful balance between taking themselves very lightly (preposterous track names, playing games with the listeners expectations, playing music that has absolutely no chance of mainstream success) and taking their music very seriously (making the vast majority of “progressive” musicians look like clueless amateurs). There’s a lot of nonsense said about this band: to clear up any misconceptions, they are not jazz, their music is not “random” and they do know what they are doing. Frankly, if you think it sounds like pointless rubbish, you are the one at fault. Now, that is not to say that we can’t attempt a little criticism!

Compared to Skullgrid, their previous record, the production style has shifted slightly in favour of guitars; I’m not entirely happy about this as the bass end of the Warr Guitar (look it up) has a satisfying meaty quality that has largely been dropped and the drums also feel a little less full. Still, the mixing is excellent in that all the parts are crisply separated and exposed, making it fairly easy to track what is going on in these absurdly complex arrangements. We can also be grateful that they have not gone to the “bees in a tin can” aesthetic preferred by many of their influences.

A number of minor innovations and tweaks to the band’s sound and writing are on this record — I could spell them out but honestly it’s more fun to discover them for yourself. In general, the songwriting is more repetitive — this is not really a weakness when found in such erratic music, but it is noticeable especially in the drumming. The snare in particular is used repetitively for extended periods, which combined with a relatively low tom mix makes the drums feel less varied and, well, fun. One could link this to new drummer Weasel Walter but blaming personal drumming style doesn’t really fit the data — this is a band that composes on paper, and Walter has said in interviews that he has found the music challenging and had to adapt his technique. At the same time, he’s made a major contribution to the songwriting and seems to largely run the band’s online presence. An easy criticism to level would be that the album is very short at 28 mins, but actually I think this is a great strength; such exhausting music is best enjoyed in moderation. I suppose one might claim that the record represents poor value because of this, but I don’t think $10 is very much for a top-tier record in a niche genre. I actually pre-ordered the $25 cd + t-shirt bundle (and paid as much again in shipping and tax from the USA; a UK distributer would be nice!) The T-shirt is great, featuring a huge and vivid rendition of the album’s fearsome artwork, and as a reward for pre-ordering I received an audio download well before the release rate. In general, mail-ordering a CD and receiving a download ASAP is my favourite distribution method, truly the best of both worlds, and I’ve happily paid over the odds for it on multiple occasions…

To sum up; perhaps this was a little underwhelming, but only because my expectations were so high. Better than Skullgrid? Maybe, maybe not. Regardless, this is easily some of the best composition going on in “popular music”, and the band really have a way of making everyone else look like ignorant slackers.

Between The Buried And Me — The Parallax II: Future Sequence

The Parallax II: Future Sequence (Artwork)

Some facts about this record:

  • The majority of the lyrics are unintelligible
  • The remaining lyrics are vague
  • There is little by way of obvious structure
  • The record is 72 mins long
  • The instruments are well-arranged and the melodies and rhythms are inspired
  • The level of technical playing and musicianship is outstanding

There is actually a very equivalent musical genre out there: Italian opera

It’s difficult to process the contrasting sections, cheeky interludes and furious chugging. WHY ARE YOU SO ANGRY. I DON’T UNDERSTAND WHY YOU ARE ANGRY. STOP SHOUTING. I really don’t have a problem with aggressive music and metal; the transitions are exhilarating and the resulting work feels more sincere and less contrived than, for example, Dream Theater’s work (which manages to be both more emotionally shallow and technically excessive). In principle, the scope is very similar: from the album name, artwork and rambling clean vocals about astral projection, they are clearly trying to communicate something deep. But they take 72 minutes of somewhat challenging music to explore… what? It’s difficult to enjoy the tracks simply as technical compositions – given the length, there are few rewards in the form of references and reprises. If you turn to the lyric booklet, things work a lot better as the music really does follow the story and there is some thought-provoking stuff there. But if you HAVE to use the booklet to enjoy this record then the booklet should have been printed on A4 with a clear font, durable binding and the words READ ME on the front. If you go to the opera these days you are provided with a plot summary, surtitles and live acting. I appreciate that an hour-long music video may be a bit over-budget, but this is essentially good music with incoherent presentation.

The absolute best records of 2012 (based on a very limited sample (Part 1))

Muse — The 2nd Law

Short version: this is a crazy dance remix of a Muse/Queen mash-up. You know you’d buy it!

Returning briefly to their previous record The Resistance, Muse seem to have recently dabbled with recapturing the spirit of earlier songs: Uprising feels like a very cynical attempt to re-make Knights of Cydonia, while Unnatural Selection has a good stab at Citizen Erased but falls short, partly in its crisp, plain production. Well, it’s third time lucky, as new track Animals combines the best of Micro Cuts and Ruled by Secrecy, with a 5/4 time signature thrown in for good measure.

External inflences are much more important to this record however; between the James Bond quotation in Supremacy, miscellaneous Brian May guitar squeals, Queen-esque vocal harmony and the infamous “bro-step” wub-wub intrusion into Madness and The 2nd Law: Unsustainable, a 2nd Law drinking game based on identifiable references is inevitable. Still, it would be utterly wrong to describe any of this as “derivative” (except in a very narrow sense) — this is important work being done to bring together diverse influences and show people what can be done. Panic Station makes 70’s disco cool for heaven’s sake.  The 2nd Law: Unsustainable shows how the Skrillex formula of “lame sequenced music:epic wub-wub drop:repeat” can easily be improved by replacing the “lame sequenced music” with something that is inspiring in its own right. There have been about 600 years of work done on how to build musical tension without just boring your audience into wanting something else to happen. Muse aren’t ashamed to draw on it. Follow Me is also pretty brave as it essentially changes production style between verses and choruses, giving the might of pumping compression without killing the track’s structure. I really hope that hundreds of dull pop producers were smashing their heads against expensive mixing desks when Madness was released — they’ve been trying to make exactly this track for Cheryl Cole et al for years now, and simply lack the musicianship and creativity to do it. This album is a real gift to song-writers and producers.

How does it stand up as a record in its own right? Well, Survival didn’t exactly bode well, with it’s preposterously serious arrangement set against outright terrible lyrics and cheesy riffs. In context, following Panic Station, it is a lot more acceptable as your inhibitions have already been knocked away. Much as I like the arrangement in the chorus of Save Me, I think a lot of people will find it a dull ballad. The overall concept is great: I’m pleased to see mainstream bands endorsing environmentalist concepts, and the closing pair of title tracks are very powerful (although as a thermodynamicist I must object to the insinuation that the Earth is an “isolated system”.) And so we come to the elephant in the corner:

“save me”, “free me”, “follow me”… this album should be renamed “The Imperative Tense”
— Jonathan Archer, MPhys

Muse’s lyrics have never been that great. On the earlier records it simply doesn’t matter, as the vocals are largely buried in distortion. When they really are the centre of attention, they are good enough and Unintended is a very moving song for example. But as they’ve moved towards a more pop-music aesthetic, it’s becoming more of a problem. You can string cliches together for an album or two, but you can’t get to this level of stardom and 7 albums without being criticised for lines like “Embedded spies, brainwashing our children to be mean.” Explorers is probably the first canonical Muse song that is actively boring. It’s embarrassing, guys. Sort it out.

Coheed and Cambria — The Afterman: Ascension

Coheed and Cambria’s opening tracks are always great; creepy instrumentals which are usually interrupted by loud guitars for Track 2. The Afterman: Ascension doesn’t disappoint, yet brings some variation — what is this? Dialogue?! Then a beautiful variation on the opening theme for In Keeping Secrets of Silent Earth: 3 (which has already been reprised on Good Apollo, I’m Burning Star IV, Volume 1: From Fear Through The Eyes Of Madness), and no rude interruptions. For those who’ve read this far without being familiar with Coheed and Cambria’s material, you are correct in surmising their love for ridiculous titles. There’s always a logic to them but it can be a little… remote… Coheed are basically a modern progressive rock band (or “nu prog” as it is called by the truly desperate), but their sound palette is largely drawn from metal. (It would be a disservice to call them a progressive metal band.) Synthesisers and electronics are usually present, but take a back seat to deceptively simple riffs and deceptively complex arrangements.

I don’t generally have any idea of what is going on in these records. While it’s often possible to get some semblance of a story or a moment from individual songs, the overall events are beyond me. I understand that there is a (graphic) novel/comic project running in parallel, but to quote the inimitable Plinkett on Star Wars Episode I:

“… don’t any of you ****** tell me that it was explained more in the novelisation or some Star Wars books — what matters is the movie. I ain’t never read one of them Star Wars book, or any books in general for that matter, and I ain’t about to start .”

It’s refreshing that with The Afterman: Ascension one can at least get a decent sense of story-like things; characters are explicitly named in lyrics or song titles, and you might even learn something about them. The rhythms and melodies are as inventive as ever – a significant part of the difficulty in understanding the lyrics comes from the atypical phrasing. I’m not sure I’d change this; we come to Coheed for crazy melodies that nobody else would write, set to tasteful and engaging rock/metal arrangements. This album really delivers, while containing enough new sounds and experiments to overcome the slight stagnation of their last two records. I would recommend it to established Coheed fans and laymen alike.

Plan B — Ill Manors

What? A hip-hop/urban/what-have you record? Not my usual scene I’ll grant you, but this is the kind of work with so much attention to detail it makes everyone else look lazy. It’s accessible for all the right reasons, and never boring. The title track easily takes the title for “Song of the Year”; the chorus is just a great piece of writing. Don’t believe me? Take a look at the first line:

"ill manors" chorus

Over four bars, the first note of the bar is progressively brought closer to the bar line. This builds up the tension and lets it move easily from slow and epic to tricky and syncopated.

Unashamedly topical, I’d accuse the song of being crude and over-the-top if it didn’t seem so sincere. This holds for the whole record – “Pity the Plight” has minor descending piano motifs, eerie synth pads, bleak poetry, actors crying and screaming. Heavy-handed? Maybe. Traumatic? Hell yes. Justified? A lot more so than if it were on a Dream Theater record.

The last album which make me this uncomfortable was The Inevitable Rise And Liberation of Niggy Tardust — and this is much closer to home. I can’t really join in with the chorus when I am a “little rich boy”. Yet as with the Saul Williams/Trent Reznor collaboration, I’m riveted by the combination of passion and sophistication. The conflict is that culturally the music isn’t openly aimed at me, but good music will of course reach through regardless. A suspiciously wide range of bands and are quoted and even name-checked, and there’s a fantastic rant about newspapers, suggesting that this is actually intended to reach the middle class and we’re meant to feel this bad. Great.

As a film soundtrack, this falls into the depressingly small group of concept albums that have an easily intelligible story. The songs follow different characters through connected events. Essentially it’s about being poor on a London estate. As a key theme of the album is that people misunderstand and misrepresent this culture, I can’t possibly comment on how authentic or appropriate it is. Everyone is criticised; parents, schools, police, government, media – while a sympathetic portrayal, it is clear that on some level the characters themselves are also to blame, and circumstances are given as explanation, not excuses. It’s not the most positive or constructive message, but it captures some of the ideas and problems of our time very effectively. I’m left upset and angry, but with no real outlet other than making my own angry music.

Music video of the year

Gangam Style. Because pelvic thrusts are still funny.

2012 gigs retrospective

I would like to offer a list of my top albums of 2012, but I’ve only just acquired some of the top candidates, so in the meantime here are the gigs I went to:

27/01/12 Explosions In The Sky

Touring in support of their 2011 album Take Care, Take Care, Take Care, this was a strong performance from the Texans. The set was well-balanced between their albums and it was a pleasure to hear some of my favourite tracks. A particular highlight was the powerful new track Let Me Back In, complete with eerie samples and elegant guitars penetrated by deafening, dissonant clangs. Explosions are a band I recommend to almost anyone as their work is very musical, quite accessible and refreshing to those unfamiliar with post-rock; a good gateway. While generally associated with the more beautiful, clean side of the genre, on this night they gave a pyrotechnic performance of Greet Death in which the melody was almost buried in noise. If you knew what you were listening for, it was glorious;  I can’t speak for first-time listeners.

Black Mass and Lanterns on the Lake gave memorable supporting performances of contrasting but fitting electronica and folk rock, respectively. Black Mass operated his pile of equipment from behind a zip-up hoodie, the uniform of the solo electronic musician. Low-frequency rumbles and ingenious samples made good use of the system, but didn’t really animate the crowd. Lanterns on the Lake were charming and I intend to keep an eye out for them in future.

25/02/12 Rammstein

I first saw Rammstein aged 17 on the Reise, Reise tour, and it was great to catch up with them again. Apart from a few new songs and a couple of new toys, they haven’t changed. Quite possibly the greatest rock stage show on earth with multiple performance areas, pyrotechnics, robotic wings, a giant cooking pot, simulated buggery, more pyrotechnics, a foam cannon, and a special different kind of pyrotechnics with more fire. Probably the only band in history to ejaculate into their joyous audience twice in one show. (Then again, there’s some pretty weird performance art out there…) I happen to quite enjoy the music too. Deathstars opened and set the tone nicely with some rather silly songs in a related style, and with an adequate level of showmanship and presence. There’s really no point in trying to outdo a band that arrive in a procession with flaming torches and giant braziers, into an arena ready to sing along with them in German.

12/06/12 Sunn O)))

Possibly one of the most life-changing gigs I’ve attended. First, some facts about Sunn O))):

  1. Only half of the characters in Sunn O)))’s name are pronounced
  2. They are named after their amplifiers
  3. Their stage set is made out of amplifiers
  4. Most of their songs are at around 5-10 beats per minute (for reference, trance music is around 125)
  5. They have collaborated with a ridiculous chunk of the global avante-garde noise/metal scene

So you have a bunch of guys playing a note for 10 seconds and listening to feedback. What’s the big deal? Firstly, those notes sound incredible. The amps were arranged in a semicircle and interact with the guitar, each other, the PA and the shape of the venue. The low-frequency vibrations are so powerful that I spent probably the first 10-20 minutes of their set discovering the resonant frequencies of different parts of my body. Secondly, the atmosphere was effective. The venue was flooded with so much smoke that it was impossible to clearly see much of the stage. The musicians, cowled in huge robes, drifted in and out of view, of existence, while a few rays of light poked between those massive speaker stacks. Essentially, they played a very extended version of one track, Aghartha. I think it lasted around 90 minutes, but it became difficult to keep track of time. At the end, the sound was gone. There was silence, then applause, then it was quiet again. An encore was not even a relevant concept to what we had experienced.

7/09/12 Between The Buried And Me

BTBAM made a great sound, but I found it difficult to really engage with the songs. I couldn’t feel strong structures or themes to jump onto. I suspect this is largely due to lack of familiarity with the music, and I’m trying to rectify that. Progressive music does generally reward repeated listening. The show was simple but accomplished and the audience received it pretty well. Opening act the Safety Fire won some early enthusiasm from a thin crowd with good use of time signatures and samples. They deserve credit for also having an attractive stage layout and easily the best T-shirt designs. It did seem however that most of us were there for Periphery, the main support act. Periphery showed great chemistry with each other and with their audience, and rattled through a good mix of songs from their debut and follow-up. However, there were several issues: their drummer had been injured and a stand-in was playing (very ably I might add). The set was relatively short and they were unable to play an encore despite united and extended crowd demands. The vocalist was not on top form, possibly due to illness, and struggled a little on their signature high clean vocals. It’s a shame that on an occasion where so many people had come to see Periphery, we didn’t really get them.

9/11/12 Funeral for a Friend

Funeral for a Friend are easily the biggest band to play in Bath in some time, and I felt somewhat obliged to support this. The gig was intended as a warm-up for their tour, and unfortunately it showed. The young audience was refreshing if a little alarming (“I’m too young to feel old at a gig!”) and I was taking care not to flatten small teenage girls when the moshing broke out. They seemed taken with the band but were probably a less-than-critical audience – these songs of teenage romance in a hardcore style always appeared a little insincere, and it’s hard to suspend disbelief as the age gap widens. The band need to act like moody teenagers to pull this off; as it is I’m not really sure what they were going for. The music isn’t sophisticated enough to speak for itself, and we need a show. Enter Crossfaith, the main support act. Fusing metal with electronic dance music isn’t exactly a new thing, but it certainly is a crowd-pleaser, and their dubstep screeches were suitably topical. More important was the band’s energy – they sprinted onto the stage and simply demanded that the crowd come forwards and start jumping with enough conviction that we were easily engaged. The best mosh pit of the night broke out spontaneously in their cover of Prodigy’s Omen. They even had the charisma to get away with a drum solo. I wouldn’t buy the record (ultimately the songs were nothing special) but I’d happily see them again.

Afterthoughts

The best overall gig was Explosions in the Sky, in terms of sustained interest and quality. It’s a close call with Rammstein, though. I like it when I leave a gig with a different perspective on the music; Sunn O))) left me with a different perspective on all music! I would like to catch Periphery at their own show, they’re clearly a great band and can definitely sustain a longer set. If I could command a performance from any band this year it would be Behold The Arctopus; sadly, the prospects aren’t great for a European tour. To a bold new year of loud music!

Workflow: Chemical engineering undergraduate with a netbook

A few people have recently made remarks or asked about my netbook-based note-taking and workflow. I found a few blogs and articles helpful while developing my own system, so I thought I’d share the details here where other students or academics might stumble on them and find a useful idea or two.

Last year I finished an undergraduate master’s degree in chemical engineering. For the first three years of my degree I had trouble with note-taking and revision. The main causes of this were:

  • My own poor handwriting
  • The variety of formats in which we were provided with notes and resources
  • The ease of losing miscellaneous scraps of paper
  • Disagreement with lecturers on the best way to study their material

I was somewhat wary going into my fourth and final year that things were only going to get more difficult. It was time to sort this out. What I came up with was highly successful; not only did I have an excellent set of notes for revision, but I was able to work on design projects and coursework using a range of computers, fairly seamlessly.

Netbook: ASUS Eee PC 1001P

This was an affordable machine (I paid ~£240 for it in mid-2010) with a robust design, excellent battery life and sharp, matt 10″ screen. The screen is undermined by a distracting, glossy bezel, so I covered this with matt insulating tape. This has the bonus feature of covering the webcam when not in use. I tried to track down a netbook without Windows installed, but this didn’t appear to be an option for the current generation of netbooks.

Operating system: Ubuntu 10.04 Netbook Edition

Having dabbled with running linux in virtual machines on my iMac, I was keen to get stuck in with a more dedicated machine. Ubuntu Netbook Edition was an obvious choice, with a highly netbook-oriented user interface, but with the large community and package repositories of Ubuntu. I have resisted upgrading from version 10.04 as I understand there have been several UI changes, and I am very happy as it is. There were a couple of snags setting it up, most notably the erratic brightness control and unsupported wireless drivers. I found a very helpful blog, edited a configuration file, installed the wireless drivers with ndiswrapper, and I was up and running. I also encountered a few problems as a result of using wubi; while a nice toy for testing out Ubuntu on a windows machine, it is not very trustworthy for long-term use, and I would advise against it.

Once I had Ubuntu Netbook Edition up and running it has been a exceptionally smooth, consistent experience. The Software Centre is quite slick but I generally prefer to use apt-get from the command line. This post isn’t really the place to go into the relative merits of operating systems and package management, suffice to say that I currently plan to stick with Ubuntu and its spin-offs, largely due to the ease of installing software.

Annotating slides: Xournal

I try wherever possible to use software that is cross-platform. However, to the best of my knowledge, Xournal is only available on Linux and related platforms. It is a fairly simple package, designed for use with a stylus as a pseudo-notepad. However, it also offers very flexible PDF annotation. Where lecture notes have been made available in advance, I have converted them to PDF (if necessary) and opened them as a background in Xournal. From there I can type notes and sketch diagrams (usually in a contrasting colour and font) as though scribbling on a print-out, but with a few key advantages:

  • If the block of text is larger than expected, I can re-position or re-size it
  • Can correct mistakes cleanly
  • Can insert duplicate slides if need to take more notes than there is room for
  • Can insert blank slides to account for extended rants
  • No need to print in advance; can download and set up while in the lecture if necessary

The final step of the process is to export to PDF. From there, the notes can be studied from virtually any device.

Technical note-taking and report-writing: LyX

LyX is a free, cross-platform and user-friendly front-end for LaTeX. LaTeX is a typesetting system which is very popular among mathematicians and scientists due to its flexibility, power and relative ease in typesetting complex equations. However, working in pure LaTeX is rather intimidating. Here is a simple document prepared using LaTeX code, the LaTeX code used to generate it, and the LyX environment for the same piece of work:

LyX provides a more accessible interface for LaTeX, with many shortcuts for common functions, an accessible interface with plenty of clickable buttons, and you edit an abstract preview of the document. The spacing, font and page layout are not accurate, and should not distract you from the task at hand. Critically, maths and symbols are interpreted, so you can see what your equation will look like as you edit it. The shortcuts, while optional, are quick and ingenious. You have to see or try it in action, really – perhaps I will branch out into video and screen capture some day. By using LyX with keyboard shortcuts I was able to keep up with those lecturers who like to “chalk-and-talk” their derivations.

Diagrams: Inkscape and GIMP

Not much depth is needed here on this one; if you aren’t aware of these two programs you should probably check them out. They’re not quite as powerful as Adobe’s offerings, but they are capable of more than many people give them credit for. If you need to draw or trace a diagram, crop an image, remove some background elements and tweak the colour balance, these two programs will be more than sufficient.

Backup and file-sharing: Dropbox

The slight loss of control and security concerns are compensated by a very slick implementation. Essentially: there is a folder on your computer. The same folder is on any other computers you own. And the internet. It holds up to 2Gb (with various ways of expanding this). It’s a real folder, and you can use aliases, command line, file managers etc. however you like. Enjoy. In combination with other cross-platform software, this leads to many delightful situations where it simply does not matter which computer you are using.

General thoughts

My workflow has changed somewhat as a postgraduate student, but I maintain that this was a suitable and effective setup for an undergraduate engineer, and I would recommend it to others. Feel free to post below if you have any questions or comments! Finding the perfect workflow has become something of an obsession, and is analogous to the guitarist’s quest for “tone”. Hopefully some of the ideas here will help people on their own adventures.

Proposal: boycott app

I was recently pointed (thank you, Slashdot!) to an interesting list of companies supporting and opposing the ludicrous “Stop Online Piracy Act” (SOPA) in the USA. This has been widely-discussed by others more eloquent and well-informed than I, but it threw up another interesting issue. My immediate response was to scan the list for companies I am likely to patronise and note their allegiances. Problem: there are hundreds of them. And this is just one issue. How is one to keep track of the behaviour of every company out there? I don’t want to trust existing NGOs and campaigners for specific boycotts; indeed, I may not want or even be able to boycott these companies. However, if choosing between two roughly equivalent purchases that satisfy my needs, I am happy to let my own interests and principles swing the decision a little. What I seek is not an instruction, but an informed choice. I’d like to think I’m not alone.

When it comes to politics and elections there are some excellent resources available; in the UK, They Work For You is a great way of keeping track of how politicians actually vote, and actions speak louder than the words turned up by a casual internet search. When it comes to frequent consumer choices, it is not practical to carry out research every time you pick up a tin of tomatoes. It would be nice it you could have a brief summary readily available; something cross-platform that can be prepared while fuming away at the desktop, and actually used from a smartphone while out and about.

The user would be able to enter lists of companies with a brief note and some kind of arbitrary positive or negative score associated with an act. A comparison page could then be requested to aid a particular choice. Lists could be shared, naturally, but if so then some kind of citation is needed for alleged offences. The most committed users could decide in advance to how many “ethics points” a cost difference is worth. It should even be possible to get the manufacturer name automatically from a scanned barcode.

Databases and smartphone apps are areas I know little of, but I’d love to hear how feasible this would be. I can propose a name at least; it could be called “iMoral Dilemma

Analysis: Irongear Hot Slag Pickups

This article follows on from my previous post, discussing modifications to my Ibanez GRGR121EX, “Tess”. Recordings were made before and shortly after the new pickups were installed. The set of strings is the same (Rotosound pinks), as the new locking tuners made it fairly easy to detach and re-attach the strings as needed. However, the A-string broke and had to be replaced with a spare from a set of Ernie Ball Regular Slinky. This is a higher gauge so may have some influence on the recorded output of the new pickups in this range. However, I did not notice any dramatic change following the next re-stringing (more Roto-pinks).

Disclaimer

Many of the branded products referred to here are trademarked. I am not affiliated with any of the companies involved, and make direct reference to their products in the interest of accuracy and repeatability.

On online shopping

I spend countless hours trawling the internet looking at pictures of musical instruments and studio equipment. I purchase such items 2-3 times per year. This strikes me as a remarkably unproductive activity:

Useful information

  • Ability to fit into existing rigs and workflows
  • Reliability in practical scenarios
  • Quality of sound produced relative to other equipment
  • How it compares with similar items produced by different manufacturers
  • Ability to inspire new creative ideas
  • Ergonomics; comfort, ease of use

Information from manufacturers’ websites and online stores

  • How it fits into some common applications
  • Detailed specifications, from which other applications may be confirmed
  • Instruction manuals, from which ease of use and advanced capabilities may be inferred
  • Quality of sound through several arbitrary combinations of recording equipment
  • Where it fits into the range of products offered by the same manufacturer

Information from online reviews

  • Whether it survives being unwrapped and playing “smells like teen spirit” a few times
  • Whether it blows up spectacularly several years later
  • A blow-by-blow account of the argument/cosy agreement you will have with the store
  • How good it will look in a photo-shoot
  • Whether it sounds as good as your £10,000 rig (no)
  • Whether it sounds as good as your friend’s £10,000 rig (yes)

Even where the criteria are quite clear, it can be difficult to piece together the information you really need. Items such as guitars can be tried out in a store; but even then you are using an unfamiliar amplifier. For items such as recording interfaces demos are rarely available. Virtually all of my MIDI equipment has been purchased largely based on their user manuals; the free PDF user manual is a godsend for  a synth geek trying to construct a flexible clock-synchronisable program-changeable remotely-controllable live rig. Whether it will sound any good is completely unpredictable.

Pickups

A guitar pickup is not a terribly complicated device. However, there are many conflicting approaches to making the best pickups. Hand wound or machine wound? Scatter winding? More powerful magnets for high output with less noise? Weaker magnets for less string pull? I will not go into a detailed discussion of the different types of pickup here, as it has been done elsewhere many times, but it is difficult to avoid a little cynicism. Why do some pickups cost so much more than others, when the construction should be identical?

I decided on the Irongear Hot Slags for my project (see previous post): the reviews were good from a range of websites, and they seemed to offer a “modern” sound with some character. I was particularly intrigued by a helpful graph, promising a hot, mids-heavy sound. My stock Ibanez pickups have the styling of EMGs, but this says nothing about their sound. It is unlikely that they give the “flat” sound that EMG’s active range are famous for.

Method

All recording was done into Logic Pro 8 at 24 bit 44.1kHz,  using the direct guitar input of an Edirol UA-4FX interface. The Match EQ is an inbuilt effect used for calibration. I used the calibration mode to produce a graphic representation of the material it is exposed to. For each pickup configuration I played a simplified version of the guitar part for a song called “No More Days”. This is a song I originally wrote for a band at University, and has subsequently been adopted and adapted by one of my other bands, Broken Console. The studio recording is free to download.

Old vs New

Ibanez GRGR121EX Factory Pickups: Bridge (left) & Neck (right)

Examining the curves generated by the factory pickups: the bridge pickup gives a surprisingly flat response, while the neck pickup has a pronounced hump in the bass end. The small peaks and troughs may be disregarded as a consequence of the source material, which is all in one key and heavily favours some notes (and hence frequencies). The neck pickup may be expected to show a strong bass response as the string movement is greater at the neck pickup for low notes. High harmonics, on the other hand, dissipate quickly and are usually more prominent in the bridge position.

Irongear Hot Slag pickups: Bridge (left) & Neck (right)

Examining the frequency response of the Hot Slags, the bridge response is surprising; it appears almost identical to that of the factory pickup. The overall level is around 2 db higher, which is an audible difference but not huge. The neck pickup displays a similar increase in output, but the bass frequencies are even more dominant.

It is not practical to examine all of the coil-tapping and phase-flipping possibilities of “Tess” following modification. However, there is one combination I have been using a great deal, which merits inclusion. The pickup selector is in the middle position, the bridge pickup is set as a standard humbucker, the neck is coil-tapped and out of phase. This gives a very distinctive “hollow” sound.

Tess' control panel. Just as bewildering on-stage as it is in this terrible diagram.
Irongear Hot Slags: Bridge in parallel with neck pickup coil-cut and out of phase

It can be seen from the figure that the output drops substantially due to the phase cancellation, and a “gap” appears in the low-mid frequencies around 300 Hz. This gives a “scooped” sound which interacts well with high-gain amplifier settings.

Conclusions

On paper, the frequency response of the new pickups is very similar to the frequency response of the factory pickups. The “character” of the guitar has not significantly changed. However, the new options open up a range of new sounds, and a higher output is available.

This graphical examination has not addressed the subjective measure of “clarity”. It is claimed that high-quality pickups make it easier to distinguish the individual notes of chords, even with distortion. The source material is made available in compressed form below. I you would like a copy of the recordings in a lossless format, please get in touch.

Stock pickups: Bridge

Stock pickups: Neck

Irongear Hot Slag: Bridge

Irongear Hot Slag: Neck

Irongear Hot Slag: Bridge + Coil-cut neck (out of phase)

Potential developments

While the Match EQ is very convenient, I would prefer to use something a little more rigorous, and capable of returning a numerical output. It’s possible that my dabblings in programming will arm me to write something appropriate. If you know of a suitable existing tool, preferably FOSS, please let me know!

Playing back a piece is difficult to do consistently, and far from ideal. One option for future tests would be to try to directly stimulate the pickup with an e-bow or a headphone earpiece playing pink noise. A more appealing option is to construct a consistent “guitar-plucking machine”, possibly using LEGO. Any designs or suggestions are welcome.

Further experimentation is needed to confirm the claim that some pickups are “clearer” and “more dynamic” than others.

Upgrading Tess

As a post-exam treat, I set about upgrading one of my guitars. My inner artist wanted something inspiring with more options. My inner perfectionist wanted higher quality and better technology. My inner poseur wanted something that looked “custom” but tasteful.

The guitar

“Tess” is an Ibanez GRGR121EX, acquired from a guitar shop in Abingdon. It’s available for about £150 online, but the shop price was £190. Given how variable quality is in this price bracket, this may have been justified for the privilege of checking it was not, in fact, a lemon. Then again, I was planning to replace most of the parts eventually anyway…

Ibanez GRGR121EX
Complete with EMG-style stock pickups and all-black hardware. The strap buttons have already been replaced with a locking system.

Machine heads

Tuning stability was not great on this guitar. In fairness, my reference point is my other electric guitar, which is made out of resin and so not susceptible to temperature or moisture. Nonetheless, I felt there was definitely room for improvement on the tuning system. I’ve been interested in locking tuners for a while, and also fancied a change from all-black hardware to a mixture of black and chrome. The guitar has a reverse headstock, however, which greatly limits the choice of affordable locking tuners. This is one of the less obvious drawbacks to a reverse headstock; you need left-handed hardware! (Or, if you prefer, this is a point in favour of reverse-headstock left-handed guitars.) In the end I got them from axetec, along with the other parts used in this project.

Locking tuners are beautifully simple in use. Simply pull the string through the hole, tighten up, and cut off the excess. Less winding means less slipping and stretching, as well as saving you a minute or so every time you change strings.

If you loosen the thumbwheel enough, it is possible to see the gearing in this system.
As the thumb-wheel is tightened, a rod pinches the string in the hole to prevent slipping. The excess can be cut off close to the hole.

Machine heads are typically divided into “sealed” and “open” designs; open tuners have an exposed mechanism and are easy to oil and maintain. They are common on acoustic guitars and bass guitars. Sealed tuners keep the mechanism tucked away from the elements, and in theory don’t need any maintenance. They are used on the vast majority of electric guitars, and many electric bass guitars as well as some acoustics. These locking tuners are an interesting case; they are generally sealed, but the mechanism is exposed when they are loosened for restringing. Best of both worlds? Worst of both worlds? Time will tell…

The factory tuners don’t have a visible screwhole; in fact they are built with two studs on the underside which sit into corresponding holes in the guitar headstock. This is quite an elegant design, and also meant that while I had to drill new holes, the old holes would at least be hidden by the new machine heads.

The factory tuners are relatively compact, and interface with two small holes to prevent twisting. These are completely covered by third-party tuners.

Drilling the holes for the new screws was a little intimidating, as the screws extended into about ¾ of the total head thickness. I used a hand drill with a 2mm bit. Thankfully the actual holes and washers for the tuners were all a standard size, so there was no difficulty threading the new tuners through.

Control Knobs

The original knobs are made of black plastic and feel cheap. I could also feel some drag when turning them, and procured new potentiometers, assuming that these were faulty. However, while fitting the new, shiny and reassuringly heavy telecaster-style knobs, I discovered the real problem; if the knobs float just above the body, they move easily. If they are set at an angle, or too close to the surface, they drag. So, if you’re finding odd resistance from your control knobs, get a screwdriver out and try mounting them 1mm higher. It may save you a few quid on new electronics you don’t need!

Pickups

I must confess to some skepticism regarding pickups. It is difficult to understand why there is such a variety in the pricing of such a well-established and simple product. There really can’t be that much difference between the magnets and copper wire used in a £5 ebay pickup or Seymour Duncan’s finest, can there? Obviously the design is significant, and it is uncontroversial that pickup choice is one of the most significant factors determining a guitar’s tone, along with amplifier and playing technique. Still, I fancied something with a modern meaty sound, and some flexibility. I settled on a pair of Irongear Hot Slags with chrome covers. Definitely moving away a little from standard Ibanez territory here.

The Irongear Hot Slag is a high-output humbucker with a mids-heavy sound. These were nicely presented and ready for coil tapping and other trickery…

The factory pickups these are replacing are in a matt black casing evocative of EMG pickups, and strongly implying that they are active. In fact, these are simple passive pickups, set in a black resin which would have made rewiring the coils difficult.

The factory pickups are simple passive humbuckers, set in resin to add a little durability at the expense of tinkering

Unfortunately, they are also slightly smaller than the Irongears, and a buildup of resin around the base of the guitar neck resisted the insertion of a shiny replacement. After a little filing there was a sickening “CRACK” and small piece of resin came away, exposing more of the neck pocket. Once I’d started breathing again, I remembered that the neck is in fact held in place by four massive bolts, not a layer of resin, and that this was probably nothing to worry about. This created the needed space, and the guitar’s chrome content was increased accordingly.

*Just* too small

As is common for “upgrade” pickups, the Hot Slags provide separate access to each end of wire for each coil, as well as the cover grounding. This opened the way for some ambitious wiring schemes. I based the wiring on this design from the very helpful guitarelectronics.com, with an additional phase flip switch between the neck pickup coil selector and the main 3-way pickup selector switch. One note for those who wish to try this for themselves; I also had to swap the left and right sides of the coil-selector lugs to match the wiring on my own 3-way switch. Also, not all 3-way switches will work. 1728.com offers a fairly clear explanation of different kinds of switches and their use in guitar wiring.

Fiddly stuff this wiring. Horribly out of practice at soldering.

The most hair-raising part of the whole process was in fact drilling holes for the new switches. The guitar finish is fairly brittle, and drilling risked cracking and splintering the surrounding finish. For each new switch, I drilled a 3mm pilot hole from the inside of the cavity (to make sure there was room for the switch!), then, working from the face, removed more material with 4mm and 5mm drill bits. This would lead to 1-2mm of damage to the surrounding finish (if I was careful!), and from there I used a file to enlarge the hole to accept the switch. Unfortunately the switches are barely long enough to reach through the body; I intend to rectify this by removing a few mm of material from the inside with a pillar drill and large bit when I next have access to them. Still, the final result is neat and distinctive!

The top-most switch controls the phase of the neck pickup. The pair of switches above the tone knob switch each pickup between series, parallel and single-coil configurations.
£150 guitar + £100 new hardware > £250 guitar

Coming soon…

I’d like to analyse the actual differences this has made. It’s very difficult to choose pickups online, or in a shop for that matter, because of the lack of a baseline comparison. Soundclips are nice, but they tell you more about who has the nicest amplifier than who has the best pickups.

If you have any questions about this project, feel free to leave them as comments and I’ll try to get back to you soon!

Phase Boundary?

Hello!

This site is still under construction. I’ve had a few ideas that I would like to put into the public domain. They relate to music technology and chemical engineering. Perhaps I will find some overlap… I greatly appreciate the range of help and information I have found scattered across the internet, and can hopefully provide some information or inspiration in return!

Early aims are to:

  • Review all of my music gear
  • Document some modifications to my guitars
  • Analyse heat/mass transfer in some everyday systems
  • Develop some academic problems which aren’t covered by my studies

I’ve chosen wordpress, among other reasons, because of its elegant music player. The plan is to experiment a little with the review style, using a lot of sound clips. The downside is that I don’t currently have access to everything. There should be more pretty pictures and sound soon.

In the meantime have a merry Christmas!

it will take more time, so I can’t promise they’ll be up for a little while!