Automated Accompanist

January 13, 2014 at 07:47 PM · Check out this app!

Sona Cadenza

I just tried it with the Beethoven Romance Op. 50 (which is included for free) and it's pretty amazing. Yes, it's expensive but the quality is excellent and if you teach enough of these works like I do, it's VERY useful in the studio when you're not a pianist!

Replies (43)

January 13, 2014 at 11:57 PM · Very interesting. The recordings are apparently Music Minus One, but they're applying their technology to speed them up and slow them down on a predictive basis.

January 14, 2014 at 12:36 AM · only for mac? :(

January 14, 2014 at 05:34 AM · Developers have to pick a platform to start with.

The advantage to using Macs is that all of them built within the past 7-8 years or so have a built-in front facing microphone, all of them run essentially the exact same software, and the App Store provides a simple way for non-tech savvy users to install an application without having to download and run an installer manually.

I never am on any BB for long before someone jumps on here and goes on a tirade about how they can hand-build a PC for half the price with twice the specs, so before that happens, please understand: As a video game enthusiast who plays all the popular FPS and strategy games and put together my own machines since the days of the Intel 8086/8088, I get what you're saying. However, the creators of this software had a specific audience in mind, and many people in that audience (music education) have a whole lot of devices in the Apple ecosystem.

I'm looking forward to seeing this app in the iPad, especially since I've been using one in lessons already for tuning, metronome, and music theory purposes.

January 14, 2014 at 06:31 AM · I contacted the developers and asked if they had plans to create an Android app, and they said that it was already in the works and would be completed spring 2014.

January 14, 2014 at 07:44 AM · This is the same technology that used to be called Music Plus One. It was available for Windows -I still use the Windows version, and I'm very satisfied with it - but obviously the decision was made to market the program, I mean the app, for Apple now. For the times, they are a-changing.

January 14, 2014 at 08:25 AM · I used (the windows version - 'music plus one') to develop my orchestra piece (also the Beethoven Romance in F - I think it was Bart that alerted me to it. Its amazing how it follows you and you end up with a pretty good recording.

However, one can not use it alone because a real orchestra simply does not follow that well - when you plan you have to keep to a fixed tempo as its impossible - even for the conductor - to make lightning changes in speed. I guess a top-ranked orchestra probably listens to the soloist and ignores the conductor so there it might work. Overall though for training I found it more useful to play with a recording of a soloist. A really neat aspect of the software is a built in frequency chart which I found very useful to identify notes that I was wavering on.

On this subject the 'music minus one' fixed tempo recording was a bit of a disaster. The trouble was that there are enormous variations in tempo in it - from ~35 to ~60 (quarter note) and before I realized this I had quite a frustrating time 'maintaining tempo' - when it wasn't me at all.

Thus, the software is a neat way to produce a recording of you 'playing with an orchestra' that might actually fool someone into thinking that you had.....

January 14, 2014 at 12:56 PM · Even a relatively poor orchestra can follow rapid changes in tempo, if the change is clearly signaled. What they can't follow is tempo instability that blurs the sense of pulse. Now that would be a useful bit of programmatic warning to have in software. :-)

January 14, 2014 at 01:46 PM · I think that's the whole point Lydia - orchestras work fine when you are an experienced soloist. But if you are an experienced soloist I really don't think you need this software.

January 14, 2014 at 06:54 PM · Music Plus One and Sonation's Cadenza provide a way to explore different interpretive approaches to a work of music, with immediate feedback. I see them as more of an effective practice tool rather than something to produce recordings with. Being able to specify sections and repeat them makes it really valuable, as is helping students develop an active awareness of the score.

Younger musicians who have not yet developed a sense of pulse, consistent tempos, or rhythmic precision are better served by click tracks with obvious tempo markers, like what the elementary music methods offer (Essential Elements 2000 for instance).

January 14, 2014 at 08:57 PM · Very few people ever get to be experienced soloists, though, but anyone can probably learn to be followable, with practice. There's no reason why that couldn't be practiced with a tool like this, I think, except that it can't tell you what is a followable alteration and what isn't -- that would be an awesome technical feature if it could.

January 15, 2014 at 12:24 PM · Lydia, to a certain extent it can tell you when you are difficult to follow. For example, when the solo part has fast notes (triplet 8ths, or 16ths) followed by slower ones, the slow notes better be in tempo with the preceding fast ones. Otherwise Cadenza, or a human accompanist, cannot follow. After all, both the program and the human accompanist try to predict the timing of the next note based on the preceding ones. Listening closely to a MPO/Cadenza registration can be very instructive. ("Why is the computer slowing me down here? Because I slowed it down in the bars before. Duh.") Once you "train" Cadenza, it gets accustomed to your quirks, and the informative discrepancies will gradually disappear. One learns first to train oneself, and only then to train the computer.

January 15, 2014 at 01:37 PM · Bart - but after this training have you then tried playing with an orchestra? I got into a lot of trouble because the software made me 'tempo-lazy', I could take for granted that the orchestra would follow me.

In reality [maybe our orchestra was not as advanced as Lydia - or maybe it was acoustics (in a cavernous church) or that its large with ~70 members and spread out - with its inherent sound problems] I found that playing with an orchestra was like playing a duo with an elephant - you have to adjust to each other. There are invariably passages where the soloist is accompanying the orchestra and then the latter must take precedentThis the software can not (yet) do.

So, yes it was neat to play with this but, at least for me as 'beginning soloist' it was not enough. For the Beethoven romance in F I had to search for a soloist that both kept strict time (almost all of the recordings have large tempo variations - its the 'urge' of the piece) and that played slowly enough that I could play along.

But I could not find anything that really mirrors the real thing.

January 16, 2014 at 12:03 PM · Elise, that could be interesting: would it be possible to finetune the program's flexibility depending on which section of the piece is being played? Or to have different flexibility settings? It reminds me of Igudesman and Joo's Cyber Conductor.

January 16, 2014 at 01:22 PM · The notion of "training" the software is interesting, Bart -- so Cadenza remembers what you've done in the past and automatically does it in subsequent play-throughs?

Elise, being followable is learnable, but I hadn't realized that previously, despite having done concertos with orchestras in the past. Most recently, though, my teacher had me work with a piano accompanist who was instructed to deliberately throw me -- to start sections radically too fast or too slow, to try to rush or drag through a passage, etc. -- in order to force me to learn to cope (and not to panic!), and know exactly where the control points for the tempo were across the whole work (and also to know where there were tricky orchestral solos where control had to be surrendered). Importantly, the means of control varied with the rhythm of the passage -- specifically, how to signal the pulse. Undoubtedly the most valuable bit of performance prep any teacher has ever given me.

That said, I suspect Cadenza's probably not good training for the way a human would follow you, by listening for the audible pulse. For an extreme example, I wonder how Cadenza would do with, say, a Kreisler work, where the pulse remains clear but there's time taken, especially with, say, a waltz rhythm, with the first beat lengthened and the second and third beats shortened. I'm guessing this is beyond its capabilities.

January 16, 2014 at 03:29 PM · For the mathematically inclined, here is an overview of how the program works. The paper is not very recent: probably refinements as well as ports to consumer hardware and OSs have taken place.

Edit: here is a more recent paper.

January 17, 2014 at 07:36 AM · When you pay the $9.99 for the upgrade, you then have access to the editor that allows you to "nudge" the timing of the orchestra around to better suit your approach to the piece.

The thing is, the layer of information that is being added by this app to the orchestra playing, and the level of detail it is incorporating (down to ridiculously small rhythmic values) is what allows it to deal with complex tempo situations.

I used it today for a student working on Mozart No. 3, and the results were delightful. Now even the little ones can figure out what the score sounds like. Rhythm, timing, and note errors cause breaks in the performance, and it's very useful to review.

I'm a clarinetist too, and one of my kids preparing the Mozart Clarinet Concerto for a upcoming audition finally had an opportunity to play it through with an "orchestra." The ability to record, critique your playing, nudge the timing around, and go at it again and experiment with interpretation is such a valuable tool. In a few days my students who are working on Bruch and Lalo are going to try it out, and personally I'm having a lot of fun with the Mozart Clarinet Quintet, which I'll be playing in the quartet for when another one of my students performs it in February.

December 29, 2014 at 11:57 PM · I have finally gotten around to downloading this (after trying out Piano Amigo, which has fixed-tempo accompaniment), and I have to say that it's awesome. I tried it out with the slow movement of the Bach Double (sadly, the only option is for 1st violin, it doesn't have the option to play 2nd), and then with the first movement of the Beethoven concerto.

The following works pretty well, although it seems like it resets to the default tempo whenever you are not actively directing it otherwise (for instance, if there's a brief orchestral tutti). That by itself is good practice for anyone who needs to clearly lead an accompanist or an orchestra -- I found that what naturally works to slow or speed up a human also seems to result in the Cadenza app matching the tempo correctly. It also copes in a fairly natural fashion with ritards and the like (indeed, it may be somewhat more responsive than an actual orchestra, although not quite as responsive as an excellent pianist, I think).

Fantastically useful for understanding how the piece fits together. (Also, for the Beethoven in particular, intonation is actually easier against the accompaniment, as you have the entire harmonic structure to guide you.)

I did find the physical logistics of using it to be something of a conundrum. You have to use headphones. I have IEMs (studio-quality earbuds), on a normal headphone-length cord. I plugged those into my iPad Mini. But if I put the iPad on my music stand, the cord got in the way of my bow arm. I ended up putting the iPad on a side table on my right side, so that the cord fell straight down to waist height, away from my bow arm, before extending out to the table. I also discovered that if I turned up the volume all the way, so I could clearly hear the orchestra, I could then not properly hear my violin. The solution for that turned out to be using only the right earbud. That way I could clearly hear my instrument under my left ear, but still get the accompaniment clearly audible in my right ear. It also meant that I had the impression of a big orchestral sound, which forced me to remember to project at full concerto volume.

If I'm going to use this app on a routine basis, I might think about getting wireless earbuds instead, which would be less inconvenient.

December 30, 2014 at 10:34 AM · A similar program that I use is called MuseScore. It is free and allows one to develop a full orchestra score or a simple piano accompaniment and play it back at a tempo of your choosing.

You can find scores for the program for a lot of classical pieces, for free! Or if you are going to use a piece a lot, you can create your own score from sheet music.

Playback can be through headphones or the computer speakers.

It is not as convenient as a phone app as you need a computer. I believe it comes in Mac and PC versions.

December 30, 2014 at 01:56 PM · Carmen, is it any good at following the soloist, the way we are told Sona is? I'd be a little surprised if it were.

December 30, 2014 at 02:44 PM · This is a very interesting subject, however I have introduced a live accompaniment with live amateur musicians and amateur soloists in the Chicago area. Our latest adventure is at the Seman Violin Shop in Skokie IL.

We are meeting at 6:30 PM on Friday January 16th at the Seman Violin Shop’s auditorium – 4447 Oakton Street in Skokie IL. Our live orchestra is playing the Brandenburg Concertos 4 and 5.

We are also playing the B Minor Bach Suite for Flute and Strings. Also on tap is Vivaldi’s “Winter" from the Seasons. We need a super violinist for the Vivaldi. If there is time, I will solo on 1st movement of the Mozart K216 3rd Violin Concerto. Any one who comes to this event is invited to solo on the 2nd and 3rd movements of the K 216 as well as Vivaldi's "Winter".

Currently we have a 23 piece chamber orchestra. If you are interested, contact me through Also bring your instrument and a music stand. It should be a fantastic evening !!

December 30, 2014 at 05:12 PM · >> ... is it any good at following the soloist...

No. It has no ability to dynamically detect live play and adjust tempo accordingly. You can adjust tempo before you play it back in a matter of a few seconds.

You say the app has that ability? I guess I should have read the web page more closely. I just took a quick peek. That would be quite an accomplishment for anything other than a simple melody. I'll have to take a look at it in more detail.

December 30, 2014 at 05:30 PM · I have MuseScore; it's just music-notation software with computer playback. It's non-expressive and mechanical, as you'd expect.

Cadenza uses Music Minus One and similar accompaniment. And it adapts to you, like humans would. That's what makes it amazing.

What I've found really interesting is that it adapts the way that humans would. If the tempo is radically wrong for your interpretation, for instance, it responds most accurately if you change the tempo in a way that would clearly allow humans to follow you. If you do something unfollowable, you will hear it -- the app will sync back to you, but you'll hear it get apart, just like a real accompanist would. This is actually a very useful behavior.

January 1, 2015 at 05:37 AM · Can you still download music plus one for pc?

January 1, 2015 at 08:34 AM · I don't know. Classic FM did an advert featuring somebody singing in his bath, out of tune of course, alongside a recording of an operatic aria. Is this the kind of thing you mean by "Music Plus One"?

January 1, 2015 at 07:40 PM · "Music Plus One" is the experimental precursor to the Cadenza app. It doesn't look like it's available any longer.

January 1, 2015 at 11:47 PM · Thanks Lydia - I thought Darren was being over positive by mistake and that he really meant "Minus".

January 2, 2015 at 01:21 PM · Here is an interesting demo of the Cadenza software: Mendelssohn E minor last movement with a lot of extreme tempo distortions by the soloist

January 4, 2015 at 09:59 PM · I now tried the Cadenza software. You only need an iPad and ear plugs. The software is free. In addition, there is a remarkable selection of free tracks (mostly slow movements of violin concertos). The last movement of Wieniawski d minor is also free. I tried it. The software perfectly recognized the relatively long violin solos in the introduction. It was like with a conductor. One can take all rhythmic freedom he or she wants, the orchestra will be there just in time. I also tried the slow movement of the Bach double concerto. Worked nicely. Same with the slow Vivaldi Spring movement. The slow movement of the Beethoven concerto with its rhythmic freedom was a particular pleasure. Cadenza is a very notable improvement over MMO. Try it if you have an iPad. This won't cost you a penny. They already caught me. I will buy tracks (which currently are really cheap compared to conventional MMO recordings)... I see this software as a great practice and fun tool but not as suited for more serious recordings. Basically, you still play along a prerecorded version (if you like that version or not), however with much more flexibility compared to MMO.

January 8, 2015 at 08:59 PM · Hi, Paul from Sonation here. Thanks for all the kind words and suggestions!

I just wanted to chime in about the wireless headphones suggestion to save someone from some disappointment: Although they would be more convenient, they don't work with Cadenza because the delay they introduce makes it impossible to accompany you in real time.

Maybe we'll figure out a solution (those wires are annoying to have to work around).

Meantime, a lot of folks use Cadenza with speakers by plugging into a stereo or even a good portable system. If the speakers are far enough away from the iPad, this works really well ... and no more annoying wire in the way of your bow arm!

January 8, 2015 at 10:07 PM · In that demo of the Mendelssohn the orchestra sounded way out with the soloist most of the time.

January 8, 2015 at 11:21 PM · How is there nowhere a price listed? And no, I am not getting Itunes for seeing the price o.0 It sounds interesting to me considering there is for some concertos, like the sibelius, no good minus one recording. Maybe there is, but I don't know it. I like the Idea of Minus one, since a soloist has to listen to the orchestra aswell as the other way around. There are always just a few places where the soloist should alter the tempo / pulse just for his taste or abilities.

January 9, 2015 at 03:04 AM · The app is free. Some tracks are free. Other tracks are $2.99 or $3.99. Typically the middle movement of the concertos are free but the outer movements are $3.99 each. Actually much less expensive than Music Minus One, which typically runs about $40 for a concerto.

June 6, 2015 at 05:32 PM · Just a quick update: Cadenza is now on iPhone and iPod. It's free, and all the music in it is also free (until June 12, 2015).

The synchronization is improved, and quite a few easier pieces have been added, many of which can also be found in Suzuki volume 2 and 3 for violin and cello. to download.

June 7, 2015 at 02:39 PM · Did they get rid of their buggy desktop app?

June 8, 2015 at 04:41 AM · Yup. It's iOS only now.

June 8, 2015 at 05:27 PM · Paul Smith -- Thanks for letting us know the app is on iOS. Wow, this is truly one of the coolest apps I've tried. However, it keeps crashing after a few bars of Mendelssohn concerto. I'm running iPhone 4S / iOS 8.3. Any ideas?

June 8, 2015 at 05:42 PM · I'm guessing it's pushing the limits of your phone. Try closing all of your apps, then rebooting your phone, and then running Cadenza as the sole app.

June 8, 2015 at 06:14 PM · Lydia -- Thanks, I've already done what you suggested. I suspect that my iPhone is too old, but hope to get official confirmation from Paul. I'll try again tonight, using my wife's iPhone 6 (if she'll let me ;-D )

June 9, 2015 at 05:40 AM · I installed the app on my iPad and was able to play through the first movement of Mendelssohn concerto without a hitch. I'm blown away by how well this works. It even knew when to resume again after the cadenza. The app is also very intuitive - I pretty much just started using it right after installation. No instructions needed, no learning curve. I'm looking forward to future experimentation, perhaps hooking it up to my amp so I don't have to wear ear-buds...

July 10, 2015 at 02:13 PM · I haven't forgotten about you and the many useful suggestions you all have made for Cadenza. So, I'm happy to tell you that the top most-requested improvements are coming to Cadenza in a few weeks. (We're in final testing now.)

Cadenza Pro will include:

  • Set and save your own start and end measures.
  • Change the overall tempo, so you can make those long orchestra intros actually match the tempo you plan to take.
  • Change the tuning of the accompaniment.
  • Make a particular accompaniment play just a bit earlier or later.
  • Listen to an accompaniment by itself (without having to play)

I'll post more when I have more info.


July 10, 2015 at 11:29 PM · Awesome!

August 8, 2015 at 11:43 AM · Cadenza app update

Cadenza Pro is now available!

• All the music is free (over 200 tracks)

• Advanced features upgrade: $8.99

iPhone, iPad and iPod Touch

Get it while it's hot!

Download from the App Store

August 12, 2015 at 05:04 AM · It took me a while to find the Pro upgrade option.

When I press the "Upgrade" button, it turns into a button that says "$-1.99". Pressing that button offers an $8.99 in-app purchase. That seems to be accurate, but the text of the button needs to be fixed.

And downloads are failing. For instance, "Failure downloading williams_princess_leia (655.-238)". I haven't been able to download any new tracks. Previously I'd get occasional failures but not constant failures. iPad Mini, current iOS, perfectly fine Internet connectivity.

I'm happy to give you money, but the app has to work. :-)

This discussion has been archived and is no longer accepting responses.

Facebook Twitter YouTube Instagram Email is made possible by...

Shar Music
Shar Music

Pirastro Strings
Pirastro Strings

JR Judd Violins
JR Judd Violins

Los Angeles Chamber Orchestra
Los Angeles Chamber Orchestra

Dimitri Musafia, Master Maker of Violin and Viola Cases
Dimitri Musafia, Master Maker of Violin and Viola Cases Shopping Guide Shopping Guide

Metzler Violin Shop

Southwest Strings

Bobelock Cases

Johnson String Instrument/Carriage House Violins

Jargar Strings

Bay Fine Strings Violin Shop


Los Angeles Violin Shop


String Masters

Nazareth Gevorkian Violins

Laurie's Books

Discover the best of in these collections of editor Laurie Niles' exclusive interviews. Interviews Volume 1 Interviews Volume 1, with introduction by Hilary Hahn Interviews Volume 2 Interviews Volume 2, with introduction by Rachel Barton Pine