marxy's musing on technology

We mostly use Apple Macs here (except for a Windows XP netbook for some ham radio software). We love Apple's iWork suite but my wife is required to work on documents in Microsoft Word.

She runs Microsoft Office for Mac 2011 on Lion. We have the latest updates of both but her day to day experience is very poor.

The documents she works on are large, hundreds of pages, with track changes enabled and showing lots of history.

Every day, every few hours, Word hangs in some way. Sometimes it shows a black window or a blank dialog box. Mostly we can't quit the program nicely - we must force quit to get out of it.

Word does recover the file without losing too much but it can be distressing for her when deadlines are approaching.

Microsoft do acknowledge quite a few "known issues" but no crashes in Word (only Excel).

This morning, just before heading out the door, we were unable to copy a PowerPoint presentation to a USB key. I know from past experience that Office holds files open even though the window is closed for some reason (no idea if this is still the case but it used to be). We tried to quit all the Office apps, they did appear to exit but when we tried a restart it was prevented by Word.

This software has been around for a long time. People rely on it. I'm embarrassed on behalf of the industry that a user can have such a bad experience every day. LibreOffice is looking very tempting again.

I'm all for going paperless and have switched to paperless notifications of most things, (although I do find myself printing a lot out to hand to my accountant at the end of the year which rather makes me feel like a distributed printing service).

A few Westfield shares means that I get notifications such as the one shown here that just came in.

I noticed that it took rather a long time for my email client to download the email and the "hero" image of "Westfield Sydney City - Feb 12" rendered progressively.

It turns out that the image they embedded in the email, from an email & SMS marketing service called Vision6, is a 6MB image which measures 3495 x 2713 pixels!

It's a lovely image but really, this is abuse of my inbox. Please don't do that.

On the bench at the moment is the Ensemble RXTX SDR. I've built a Softrock receiver in the past but never tried transmitting so this should be fun. I'm building it to cover 20m, 30m and 40m which seems a pretty useful range.

It's a bit hard to order a Softrock, the site often says "check back soon". I happened to be reading the reddit amateur radio site when someone noticed stock so I got in.

There's still a bit to go but I'm now up to the point where I can try the receiver.


(That photo is from before I was ready to try the receiver). The hairy thing for me with these kits is the soldering of tiny surface mount components but I find that I'm getting better (although probably using too much solder) and also the components seem very robust.


Not too bad eh? (Believe me, it's really tiny).

This model has an Atmel processor which does USB so that the computer can control the frequency and transmit line.

My build has not been all smooth sailing. On receive it was super deaf - turned out I'd wound the wrong T5 and it was attenuating the receiver so much that it made almost no difference when the antenna was connected such that I thought something was unconnected.

There's not many stations on but here's a video of a little reception that sounds pretty good, until my WSPR station transmits and blots everything!


Here's a bit more reception:


The Kodak Zi8 does a pretty good job on these clips I think.

Since doing some research on audio quality this week for a RN breakfast panel responding to Neil Young's comments I've been hunting for ways to experience the best quality audio I can get out of my Mac.

I don't have a SACD player but I found some rips in the form of .dff files that contain 1 bit encoded streams at 2.8 MHz. To play these on a Mac you can AudioGate from KORG. It's free but they either want you to have some of their hardware or alternatively use your Twitter account to tweet a little marketing. This seems like a fair deal to me.



The software is written in some kind of cross platform library so it looks pretty weird on the Mac but it works and sounds good. Oddly it claims to be clipping pretty frequently but maybe the track is normalised to use the full dynamic range.

I'm outputting to an Edirol at the highest bit samples and rate I can do.


The software will convert to formats including FLAC:


but as I mentioned they force you to tweet some marketing. Haven't seen this before.


Interesting....

Here's a demo of a morse decoder that works pretty well. MorseDec.


A new version, 1.2, came out today that fixed a bug in the spectrum display. Here's it decoding the VK2WI morse beacon on 3.7MHz. This is simple acoustic coupling to the iPhone's microphone. It's 2:30 in the afternoon and there's a bit of fading so I think it's doing a pretty good job.

Musician Neil Young's interview with Walk Mossberg at the recent All things D: Dive Into Media conference last week is worth a look.

Young says that in the studio he's pretty happy with masters recorded at "24/192" which is presumably 24 bit at 192kHz sample rate (lossless compression). He bemoans the fact that most listeners currently get "just 5%" of the music data in the form of MP3 compressed audio.

I think that's overstating it a little, while the file size might be 5%, the genius of lossy compression is that it doesn't sound 95% worse. Despite apparently having been working with the late Steve Jobs on bringing better quality to portable players, Young never mentions better codecs such as AAC which Apple standardised on, Apple Lossless or the freely available FLAC.

My setup here has a number of external USB audio devices and to find out what their capabilities are you use the "Audio MIDI Setup" app found in the Utilities folder. My day to day headphone driver is a Corda "Move":


Like the Mac's internal audio, it's capable of 16/48, but interestingly it was defaulted to 16/44.1. This probably makes sense as pretty much all my music is from CDs which are sampled at 16/44.1kHz. I have some uncompressed tracks, you can see them in iTunes by getting info:


Again the sample rate is 44.1kHz and the sample size is 16 bit. I would assume that matching the output DAC to the sample rate of the recording would avoid resampling errors and extra CPU effort.

Would a move to 24/192 make a big difference?

Sampling at 44.1kHz means that the theoretical highest frequency that can be reproduced is 22kHz but a tone at that frequency would end up being a square wave that would be low passed filtered back to a sine wave - no doubt bearing little resemblance to the original waveform except in frequency. While I certainly can't hear beyond about 15kHz these days, I'm confident that others, particularly teenagers, can. Going to 192kHz seems a big jump. Perhaps 96kHz would be a good next step.

24 bits instead of 16 doesn't seem like a huge leap and given that storage and bandwidth go up by a third every few months I can't see any reason not to go to 24 bit.

Compressed bit rate

The other part of the equation is the bit rate that lossy compression must fit the audio in to.

Apple made the move to 16/44.1 AAC at 128kbps in the iTunes store without being pushed a few years ago and one of the benefits of their cloud music system is that they give you a better version of your tracks if required. (AAC is better than MP3 and a bit rate of 128kbps AAC is generally agreed to be equivalent to 196kbps MP3).

My guess is that further increasing the compressed bit rate would give a greater improvement to the perceived audio than increasing sampling or sample size bits. Of course no lossy compression is where we need to get in the end.

High resolution source audio

Increasing the sample rate or sample size beyond the original that most of us deal with every day - Audio CDs, will not improve the audio. Short of original recordings, the only other widely available source of high quality audio are "Super Audio CD" (SACD). These are recorded at a sampling rate of 2.8224 MHz  and encoded as direct stream digital which is hard to directly compare with 16/44.1 but given the claimed high frequency response limit of 100kHz, seems more than twice as good, and arguably good enough for Neil Young. (It would be interesting to quiz him about this).

I found some 24/96 audio and was able to play it with VLC (although my USB DAC will only sample up to 48kHz):


Turns out I have an audio device capable of playing this without loss. It's an Edirol UA-25EX. Once the driver was installed it can do what we want:


It sounds pretty good, particularly the cymbal sounds I think, but to be honest at my age it's probably lost on me.

Pay for quality option

Another interesting thread in the interview was that "piracy is the new radio". He's talking about customer learning about new music by first getting a copy from someone and then going on to buy the tracks.

We already pay a little extra for an HD version of a movie, (and I always do pay the extra personally), it makes sense to offer more options including very cheap versions for small screens.

In the case of music, where it is often being consumed in noisy environments or simply as low level background, it might be good to have very low priced - (or even free) to a low bit rate, possibly compressed and equalised to suit the listening environment. There would be the opportunity to "upgrade" to a high resolution version.

Young's comment about it taking 30 minutes to download a decent quality version won't prevent piracy of these versions as it's clear that consumers currently download HD movies without much sweat and speed will relentlessly increase.

What really makes the difference to audio listening quality?

Before all of these upgrades, the first thing to upgrade is speakers/headphones and amplifier. I recently purchased a pair of Sony MDR-7506 headphones and have been very happy with them. Day to day I use a little headphone amplifier and have built several Chu Moy amplifiers that really sound great.

Young is kind of right but doesn't realise that our existing hardware is already capable of increased quality in the form of lossless support and slightly higher bit rates. I'd like to see sliding price scales for better quality digital audio so that those who want it can get it.

Discussion on RN Breakfast

We had a panel discussion on RN breakfast this morning. Got a big listener response which was great. Here's co-panelist, Robbie Buck, standing by for air on the "brefast" show:


We had a bit of fun and played a vinyl record and then an MP3 for the listeners, many of them on AM radios. Lots of emails from people preferring the vinyl version.