4 ms·

Capo: My new Mac app for helping musicians learn their music

17 points by liscio 17y ago

liscio 17y ago
I've been a full-time indie Mac developer since Feb 2008, and this is the third product in my Mac products lineup. It's not the same kind of 'startup' that you folks tend to talk about (not a hosted service, in the cloud, etc), but it's what I do for a living. Questions about the business, the tech, the features, etc.? I'll gladly answer them here.
- _pius 17y ago
  Congrats, I saw a pretty solid mention of your app on Daring Fireball earlier this week.
  - liscio 17y ago
    Thanks! John was very kind to have written such a glowing comment.
- mtinkerhess 17y ago
  Pitch and speed adjustment are useful features for learning music from recordings, but Audacity has those for free. Are the features your program offers over Audacity (marking sections, drag-and-drop importing) there for convenience or do they allow you to do things that aren't possible in other audio programs?
  - liscio 17y ago
    I think this comes down to really "living with the app for a while" to make that decision. I've used other apps, including other 'slow-downers', and I really just couldn't find my footing in them. Some are horrid cross-platform apps with unfortunately chosen keystrokes, and pretty much all of them had terrible UIs. After using them, I decided to write Capo. It was a need that, in my opinion, just wasn't being met. I wrote an app that can run on your laptop, with your guitar on your lap, and you can control it very quickly and figure out a song with no fuss. I take guitar lessons weekly, and this app scratches my itch beautifully. You don't have to visit deep menus, fancy settings panels, or anything out of the way to accomplish the main task which Capo does very well. I hope this answers your question (albeit in a very wordy, roundabout way).
    - mechanical_fish 17y ago
      As a banjo player, let me testify: Slow downers are really useful, and they really need to be driveable using only your left hand, because there are these big fingerpicks on most of the fingers of your right hand. It's really hard to shake hands with a banjo player. So the UI thing is quite important. Maybe even important enough to make me spend money on a second slow downer. ;)
      - liscio 17y ago
        Actually, I designed Capo for one-handed use. And, if you don't have a newer keyboard w/ the option key right beside the arrow keys, you can use pgdn/pgup to go between the markers, rather than opt-left and opt-right.
      - zzzmarcus 17y ago
        What's the first slow downer you use? I'm a banjo player as well but haven't found a good way on a mac to slow Scruggs to the point where I can distinguish his notes. Capo looks amazing, but if I'm going to drop consider dropping 40 bucks I want to compare :)
        liscio 17y ago
        You really should download and use the free trial to decide for yourself. In fact, all the slow-downers on the market have free trials. In Capo, you have all the functionality you need, with the limitation that after 5 minutes of audio pass through for a given song, audio quality will begin to degrade. Learn a handful of songs with Capo, a handful with the others, and let me know (use the Feedback item in the Help menu) how it went!
        mechanical_fish 17y ago
        I've got "Amazing Slow Downer". Recommended to me several years ago by Bill Evans. ASD costs $30 and was a truly awesome app in its day. And it does seem to have all of Capo's functions, except for the nifty waveform display. But the UI is cluttered, overcomplicated, and ugly cross-platform stuff. If I didn't already own ASD I would just buy Capo. As one who does already own ASD I am still considering buying Capo.
- demallien 17y ago
  How did you do the iTunes-style scrollbars?
  - liscio 17y ago
    You subclass NSScroller, and get an awesome interface designer to draw the required art for the active/inactive states. :) You can pick apart iPhoto '09 to get an idea of what bits you need, but I wouldn't advise stealing the art.
frig 17y ago
Are you doing naive speed adjustment or taking more of a recycle-esque approach?
- liscio 17y ago
  I'm using the Apple-supplied time-pitch audio unit because: (a) it has excellent audio quality (b) it's well-maintained (c) it performs well; and (d) I don't like to reinvent the wheel :)
damada2 17y ago
cool app...downloaded the trial.
Jasber 17y ago
This is great. How difficult would it be to detect the notes that are being played by the bass? This would be useful for someone who is new to playing by ear and soloing. For example, you pickup that the bass progression is G A D C--that makes figuring out the correct chords (and notes for soloing) even easier.
- liscio 17y ago
  It's not difficult to detect all the notes via FFT, slightly more difficult to detect only bass notes (harmonics come into play), and quite a bit more difficult to pull useful chords out. That said, my first Mac app, FuzzMeasure, is an audio analysis tool---so I know my way around the FFT/etc. Read into this comment however you please. ;)
gabrielroth 17y ago
The interface looks lovely -- I'm sure I'll download the demo at some point when I next pick up my guitar. I'd be interested to hear your thinking when it came to setting the price.
- liscio 17y ago
  Capo is selling to a market that includes folks who (and I'm included) would easily throw an extra $100 into a guitar because it has a nice rosewood back & sides versus mahogany. That $100 isn't going to help you play any better. It'll make you sound different, but it isn't improving your ability to play. The same can be said for buying a $30 guitar strap, quick-release pins for $20, a pedal for $80, etc... For $50 (as of July 1), Capo _will_ help you play better, and using it regularly will make you a better overall musician. So will the other tools, which also cost $50. My reasoning is probably quite similar to why they're priced the way they are--it is a seriously helpful tool to those that need it, and it is worth the money. Now, why do I think someone would choose Capo over the other tools? I think Capo is easier to use, more well-integrated with iTunes, performs very well, looks far better, and is generally more Mac-like (see point 1 below). Any one of these reasons would be a valid reason to choose Capo. In some respects, one could argue that I should charge more than my competition based on those 'better' points (see Eric Sink's software pricing article, for instance). However, Capo is a 1.0 product, and I need to build Capo's reputation, and a large following of users. I hope this answers your question (and helps others out there looking for more discussion about pricing their own products)! (point 1) The other apps are cross-platform, and have some odd quirks. The UI isn't quite right in areas, the keyboard shortcuts are strange (to me, anyway), and behavior isn't always what I'd expect.
  - anigbrowl 17y ago
    Capo is selling to a market that includes folks who (and I'm included) would easily throw an extra $100 into a guitar because it has a nice rosewood back & sides versus mahogany. Yes...but the guitar will be seen/heard on stage. People will generally spend a lot more on their t-shirt than on their underpants or socks. Nobody with an interest in musical performance wants to advertise the tedium or difficulties of musical practice, so because that part isn't glamorous. So don't base your price point on appealing to the musician's ego about investing in themselves.
anigbrowl 17y ago
It's not worth $39, certainly not $49. I haven't even used it, just looked at your web page: but I have a strong professional background in this area, so I know what it does. There are many shareware programs which do this, and others are free: this goes double for plugins, and there's a better than-even chance that a musician who likes computers already has some kind of multitrack software which accomodates plugins. They likely also have a hardware audio interface with a special low-impedance input for plugging in a guitar and got equivalent software for free. So that's black mark #1 - you're not offering much new functionality. Black mark #2 is your interface. It is beautifully clean, I applaud that. However, while an audio waveform is wonderful for engineers, it's not so much for musicians. It might be better to generate a low-resolution spectral display, by applying (say) a 256-band FFT which won't cause any computer to break a sweat but would give a more musically meaningful presentation, and set you apart from the competition. As you have already implemented pitch-independent time stretching, you probably know how to do this. Personally, I would not waste so much space on the album art either, but that's me. I'd like to see you add some more features, which wouldn't break your interface. While decomposing a a piece of music into polyphonic pitch information is hard (see http://www.celemony.com/cms/index.php?id=635 http://www.celemony.com/cms/index.php?id=635 for the technology leader), deriving the 8key* of the music from a relatively coarse FFT analysis is not so difficult. Having the key signature, and indeed the bpm, appear on the left side or over blocks in the audio display should be easily achievable and would add a lot of value. Another thing you could do is offer a button to extract or remove the top (usually vocal) melody line. This is easy: take a stereo file, invert one channel, and add it to the other. this will give you a (mono) karaoke track, since the vocals are almost always panned to the center. You'll lose the kick drums and bass too, but you could limit to the bandwidth of the human voice. Invert and add the karaoke channel to both sides of the stereo waveform, and you'll get only the center, allowing the musician to either copy or accompany the lead vocal and not much else. There's nothing more complex than a multiply-add operation going on here ((waveform.position.leftchannel.samplevalue * -1) + waveform.position.rightchannel.samplevalue ...etc.) so you should be able to do this in realtime with virtually no performance hit. Finally, consider taking the live stream of input from the microphone input (eg the guitar), FFting it, and doing a loose correlation with the FFT of the playing track to derive a little 'accuracy' meter. Of course there will be much more audio information in the track unless it's also an acoustic guitar solo, but the frequency response of the live input should be a subset of this as long as the musician is playing in time. When they start to drag or lead the backing track, the energy of individual frequency bins will exceed those of the backing track. Sorry for being so harsh, but I do think you're asking too much for something that most people will perceive as little more than a 'hello world' audio program. If I were you I would protoype the functionality in reaktor or some other visual-programming tool, add some more useful and unusual modes of display or operation as above, and then bring that back to your clean interface.
kjell 17y ago
I picked up Capo while it was in beta for $9. I bought it after about 30 seconds of playing with it. Loved everything about it. I'd previously scorned the use of slow-downers as a crutch, and more recently given in to Audacity for figuring out the blistering stuff that I'd never have been able to learn (http://www.youtube.com/watch?v=aoRRjEZaN1M http://www.youtube.com/watch?v=aoRRjEZaN1M). Its interface was the leading factor. It just worked, looked nice, made me feel good. Capo outranks audacity for speed–bending ten-fold. When the $40/50 price was announced I was however very glad I'd heard about it ahead of 1.0 and snuck into the beta program.

17 points by liscio 17y ago

I've been a full-time indie Mac developer since Feb 2008, and this is the third product in my Mac products lineup. It's not the same kind of 'startup' that you folks tend to talk about (not a hosted service, in the cloud, etc), but it's what I do for a living. Questions about the business, the tech, the features, etc.? I'll gladly answer them here.

_pius 17y ago
Congrats, I saw a pretty solid mention of your app on Daring Fireball earlier this week.
- liscio 17y ago
  Thanks! John was very kind to have written such a glowing comment.
mtinkerhess 17y ago
Pitch and speed adjustment are useful features for learning music from recordings, but Audacity has those for free. Are the features your program offers over Audacity (marking sections, drag-and-drop importing) there for convenience or do they allow you to do things that aren't possible in other audio programs?
- liscio 17y ago
  I think this comes down to really "living with the app for a while" to make that decision. I've used other apps, including other 'slow-downers', and I really just couldn't find my footing in them. Some are horrid cross-platform apps with unfortunately chosen keystrokes, and pretty much all of them had terrible UIs. After using them, I decided to write Capo. It was a need that, in my opinion, just wasn't being met. I wrote an app that can run on your laptop, with your guitar on your lap, and you can control it very quickly and figure out a song with no fuss. I take guitar lessons weekly, and this app scratches my itch beautifully. You don't have to visit deep menus, fancy settings panels, or anything out of the way to accomplish the main task which Capo does very well. I hope this answers your question (albeit in a very wordy, roundabout way).
  - mechanical_fish 17y ago
    As a banjo player, let me testify: Slow downers are really useful, and they really need to be driveable using only your left hand, because there are these big fingerpicks on most of the fingers of your right hand. It's really hard to shake hands with a banjo player. So the UI thing is quite important. Maybe even important enough to make me spend money on a second slow downer. ;)
    - liscio 17y ago
      Actually, I designed Capo for one-handed use. And, if you don't have a newer keyboard w/ the option key right beside the arrow keys, you can use pgdn/pgup to go between the markers, rather than opt-left and opt-right.
    - zzzmarcus 17y ago
      What's the first slow downer you use? I'm a banjo player as well but haven't found a good way on a mac to slow Scruggs to the point where I can distinguish his notes. Capo looks amazing, but if I'm going to drop consider dropping 40 bucks I want to compare :)
      - liscio 17y ago
        You really should download and use the free trial to decide for yourself. In fact, all the slow-downers on the market have free trials. In Capo, you have all the functionality you need, with the limitation that after 5 minutes of audio pass through for a given song, audio quality will begin to degrade. Learn a handful of songs with Capo, a handful with the others, and let me know (use the Feedback item in the Help menu) how it went!
      - mechanical_fish 17y ago
        I've got "Amazing Slow Downer". Recommended to me several years ago by Bill Evans. ASD costs $30 and was a truly awesome app in its day. And it does seem to have all of Capo's functions, except for the nifty waveform display. But the UI is cluttered, overcomplicated, and ugly cross-platform stuff. If I didn't already own ASD I would just buy Capo. As one who does already own ASD I am still considering buying Capo.
demallien 17y ago
How did you do the iTunes-style scrollbars?
- liscio 17y ago
  You subclass NSScroller, and get an awesome interface designer to draw the required art for the active/inactive states. :) You can pick apart iPhoto '09 to get an idea of what bits you need, but I wouldn't advise stealing the art.

frig 17y ago

Are you doing naive speed adjustment or taking more of a recycle-esque approach?

liscio 17y ago
I'm using the Apple-supplied time-pitch audio unit because: (a) it has excellent audio quality (b) it's well-maintained (c) it performs well; and (d) I don't like to reinvent the wheel :)

damada2 17y ago

cool app...downloaded the trial.

Jasber 17y ago

This is great. How difficult would it be to detect the notes that are being played by the bass? This would be useful for someone who is new to playing by ear and soloing. For example, you pickup that the bass progression is G A D C--that makes figuring out the correct chords (and notes for soloing) even easier.

liscio 17y ago
It's not difficult to detect all the notes via FFT, slightly more difficult to detect only bass notes (harmonics come into play), and quite a bit more difficult to pull useful chords out. That said, my first Mac app, FuzzMeasure, is an audio analysis tool---so I know my way around the FFT/etc. Read into this comment however you please. ;)

gabrielroth 17y ago

The interface looks lovely -- I'm sure I'll download the demo at some point when I next pick up my guitar. I'd be interested to hear your thinking when it came to setting the price.

liscio 17y ago
Capo is selling to a market that includes folks who (and I'm included) would easily throw an extra $100 into a guitar because it has a nice rosewood back & sides versus mahogany. That $100 isn't going to help you play any better. It'll make you sound different, but it isn't improving your ability to play. The same can be said for buying a $30 guitar strap, quick-release pins for $20, a pedal for $80, etc... For $50 (as of July 1), Capo _will_ help you play better, and using it regularly will make you a better overall musician. So will the other tools, which also cost $50. My reasoning is probably quite similar to why they're priced the way they are--it is a seriously helpful tool to those that need it, and it is worth the money. Now, why do I think someone would choose Capo over the other tools? I think Capo is easier to use, more well-integrated with iTunes, performs very well, looks far better, and is generally more Mac-like (see point 1 below). Any one of these reasons would be a valid reason to choose Capo. In some respects, one could argue that I should charge more than my competition based on those 'better' points (see Eric Sink's software pricing article, for instance). However, Capo is a 1.0 product, and I need to build Capo's reputation, and a large following of users. I hope this answers your question (and helps others out there looking for more discussion about pricing their own products)! (point 1) The other apps are cross-platform, and have some odd quirks. The UI isn't quite right in areas, the keyboard shortcuts are strange (to me, anyway), and behavior isn't always what I'd expect.
- anigbrowl 17y ago
  Capo is selling to a market that includes folks who (and I'm included) would easily throw an extra $100 into a guitar because it has a nice rosewood back & sides versus mahogany. Yes...but the guitar will be seen/heard on stage. People will generally spend a lot more on their t-shirt than on their underpants or socks. Nobody with an interest in musical performance wants to advertise the tedium or difficulties of musical practice, so because that part isn't glamorous. So don't base your price point on appealing to the musician's ego about investing in themselves.

anigbrowl 17y ago

It's not worth $39, certainly not $49. I haven't even used it, just looked at your web page: but I have a strong professional background in this area, so I know what it does. There are many shareware programs which do this, and others are free: this goes double for plugins, and there's a better than-even chance that a musician who likes computers already has some kind of multitrack software which accomodates plugins. They likely also have a hardware audio interface with a special low-impedance input for plugging in a guitar and got equivalent software for free. So that's black mark #1 - you're not offering much new functionality. Black mark #2 is your interface. It is beautifully clean, I applaud that. However, while an audio waveform is wonderful for engineers, it's not so much for musicians. It might be better to generate a low-resolution spectral display, by applying (say) a 256-band FFT which won't cause any computer to break a sweat but would give a more musically meaningful presentation, and set you apart from the competition. As you have already implemented pitch-independent time stretching, you probably know how to do this. Personally, I would not waste so much space on the album art either, but that's me. I'd like to see you add some more features, which wouldn't break your interface. While decomposing a a piece of music into polyphonic pitch information is hard (see http://www.celemony.com/cms/index.php?id=635 http://www.celemony.com/cms/index.php?id=635 for the technology leader), deriving the 8key* of the music from a relatively coarse FFT analysis is not so difficult. Having the key signature, and indeed the bpm, appear on the left side or over blocks in the audio display should be easily achievable and would add a lot of value. Another thing you could do is offer a button to extract or remove the top (usually vocal) melody line. This is easy: take a stereo file, invert one channel, and add it to the other. this will give you a (mono) karaoke track, since the vocals are almost always panned to the center. You'll lose the kick drums and bass too, but you could limit to the bandwidth of the human voice. Invert and add the karaoke channel to both sides of the stereo waveform, and you'll get only the center, allowing the musician to either copy or accompany the lead vocal and not much else. There's nothing more complex than a multiply-add operation going on here ((waveform.position.leftchannel.samplevalue * -1) + waveform.position.rightchannel.samplevalue ...etc.) so you should be able to do this in realtime with virtually no performance hit. Finally, consider taking the live stream of input from the microphone input (eg the guitar), FFting it, and doing a loose correlation with the FFT of the playing track to derive a little 'accuracy' meter. Of course there will be much more audio information in the track unless it's also an acoustic guitar solo, but the frequency response of the live input should be a subset of this as long as the musician is playing in time. When they start to drag or lead the backing track, the energy of individual frequency bins will exceed those of the backing track. Sorry for being so harsh, but I do think you're asking too much for something that most people will perceive as little more than a 'hello world' audio program. If I were you I would protoype the functionality in reaktor or some other visual-programming tool, add some more useful and unusual modes of display or operation as above, and then bring that back to your clean interface.

kjell 17y ago

I picked up Capo while it was in beta for $9. I bought it after about 30 seconds of playing with it. Loved everything about it. I'd previously scorned the use of slow-downers as a crutch, and more recently given in to Audacity for figuring out the blistering stuff that I'd never have been able to learn (http://www.youtube.com/watch?v=aoRRjEZaN1M http://www.youtube.com/watch?v=aoRRjEZaN1M). Its interface was the leading factor. It just worked, looked nice, made me feel good. Capo outranks audacity for speed–bending ten-fold. When the $40/50 price was announced I was however very glad I'd heard about it ahead of 1.0 and snuck into the beta program.