Need advice on getting started with synth kit

I am just getting started with the LittleBits Synth Kit. My kit arrived yesterday. The components in the actual kit seem to work as expected, but I ordered a few extra modules, some of which don’t seem to work. Here’s a list of what I’ve got and it’s working state:

  1. LittleBits Synth Kit (works great)
  2. USB power module (works great)
  3. Microphone input module (works great)
  4. USB audio I/O module (doesn’t seem to work)
  5. MIDI I/O module (doesn’t seem to work)
  6. Arduino module (ordered, hasn’t arrived yet)
  7. Bargraph output module (ordered, hasn’t arrived yet)
  8. Number output module (ordered, hasn’t arrived yet)

Both the MIDI module and the USB audio module come with a female Micro-USB type B port and a male Micro-USB B to male USB type A wire. Most USB devices give a male USB type A plug, so I figured I would be able to plug things in by using a male Micro-USB type B to female USB type A adapter. This hasn’t worked. I tried several devices:

With the USB audio module, I tried plugging in my Blue Snowball USB microphone. The configuration of modules was USB power > USB audio I/O > Speaker. It got power (the red light on the micrphone lit up) but didn’t capture any audio.

With the USB midi module, I tried plugging in my Alesis Vortex Keytar into the USB port on the MIDI module. It didn’t get power initially, so I tried using DC to power it. I know the keytar works because I used it with other USB midi devices to test it. The configuration of modules was: USB power > MIDI I/O > Oscilator > Speaker.

I considered also trying an XBox 360 Rock Band 3 keyboard as a MIDI input device. Unfortunately, I couldn’t connect it directly using MIDI because I don’t have a male-to-male MIDI cable. (I’ve ordered one from China, should arrive soon) But I did try connecting it using a MIDI-to-USB converter and it didn’t work – not just with the littleBits setup but also with other MIDI devices I have. I’m not sure what’s wrong with its MIDI capability. It works fine as a game controller. Any advice on getting these devices working would be greatly appreciated.

I am seriously considering ways to use LittleBits in actual music production. I have a programming background so I am going to be looking at ways to use the Arduino module to do audio effects such as making a vocoder. Has anyone published open source code of things like that using the Arduino module?

One thing I really dislike is that there seems to be no easy and reliable way to get the oscilator precisely tuned to notes on the mainstream Western musical scale. To work around this, I am thinking of maybe using my Gameboy Color or Gameboy Advance SP running Little Sound DJ on a flashcart connected to the microphone module using a male-to-male 3.5mm audio cable as an oscillator. Another possibility might be using my cell phone or even programming an Arduino module to act as an oscillator. I haven’t been able to find much information on the capabilities of the Arduino module.

I am hoping to soon receive a Behringer Model D synthesizer so LittleBits is kind of a good intro and it helps to try things out. Just want to stretch LittleBits just a little further to see what it can do in terms of audio. Any advice would be much appreciated!

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Hi Ben. I’ve also used the synth kit for music production. I connected external pots and sockets to the Littlebits modules and housed the whole thing in a case. It works great and can be connected to external units which use 0-5 volts CV. The two biggest omissions from the Littlebits range are a LFO and an envelope generator, which can be easily constructed as additional circuits. I found tuning the VCOs to be a bit fiddly, but it is possible to obtain relatively accurate tracking over several octaves, at least as good as most vintage analogue synths - and once tuned they are fairly stable. The secret is to connect to a keyboard and use the pitch control to roughly tune to A=440hz or whatever you choose, then use the tune control to tune the A one octave above and below - that is, to ensure that the lower A is half the frequency and the upper A is double the frequency. You will find that the middle A will have drifted a bit, but don’t worry. Now go back to middle A and retune to 440hz. Repeat the above steps until you are satisfied that the interval between the lower, middle and upper A is an octave. Once set, it should hold its tuning pretty well. You might have problems with beat notes if you try to track 2 VCOs, as they will not be precisely matched.
Hope that’s helpful
Gary

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Well that definitely would be helpful … if I could get a real keyboard connected. But given my problems with the MIDI input module, I don’t see that happening.

Both the USB audio and MIDI modules operate in USB device mode. This means you need to connect them to a USB host, typically a laptop or desktop computer. Once you’ve done this you can plug your MIDI keyboard into your computer as well and route the MIDI messages to the littleBits, as well as record the audio from the littleBits module.

If you don’t want to use a computer as the USB host you could always use one of these: http://www.hobbytronics.co.uk/usb-midi-converter

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Oh and here’s a super useful tutorial on how to tune the oscillator: https://www.youtube.com/watch?v=aw8bpQrDaZM

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Dear Ben,

Sorry to hear you are having trouble with some of the new Bits you ordered. Please email our wonderful customer support team at cshelp@littlebits.com and they will be able to help you fix or replace the non-working Bits.

Best,
littleBits

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Ah thank you so much, I think this is exactly what I needed to know to be able to use the MIDI module with my keytar. But can you tell me if that is the same as a USB to MIDI cable like this or different? I’m assuming it’s gotta be different but I’m not entirely clear on what the difference is.

Also, is there a way to connect a USB microphone without needing a computer?

I really don’t want to depend on a computer to use LittleBits (apart from programming the Arduino module) because if I was going to do that then I would’ve just done everything digitally in software.

[quote=“neveen, post:6, topic:25734, full:true”]
Dear Ben,

Sorry to hear you are having trouble with some of the new Bits you ordered. Please email our wonderful customer support team at cshelp@littlebits.com and they will be able to help you fix or replace the non-working Bits.

Best,littleBits
[/quote]Thanks. I don’t think I’ve quite gotten there yet, because based on donturner’s comment, the problem might not be with the LittleBits modules after all.

Aha! I have discovered what my problem was on the MIDI input module. I was trying to use a USB MIDI interface to connect to it thinking that was the same as a USB MIDI host. What I need is a USB MIDI host, because a mere interface won’t work.

Found a very informative video about this:

I decided that China was taking too long to get me my MIDI cable so I purchased one from my local music store today and I’m happy to report that the MIDI input module works!

I tried both my Alesis Vorted keytar and my XBox 360 Rock Band 3 keytar. Surprisingly, the cheap used Rock Band 3 controller actually works better than the expensive professional quality keytar! The Vortex would get “stuck” notes quite often when playing but the Rock Band 3 keytar never did that.

I still haven’t tried tuning the oscillator so the results were irritatingly offkey but I should give that a shot sometime soon.

I’m going to pick up my Arduino module tomorrow! Looking forward to giving audio effects programming a try.

I finally got my Arduino module and I want to try some audio signal processing, eventually to make a vocoder out of the Arduino module, using the oscillator module as input for the carrier and the microphone module as input for the modulator. But that may be a little too ambitious for a first project so I’m trying to find something simpler to start with which uses analog audio input to do something easy although I’m not sure what exactly. Maybe just a compressor.

Hi Ben @BenMcLean,
This might be interesting for you:

I did not check if this could be done with the standard littlebit bits, don’t think so…
:fearful:

Will this need any additional software or the littlebits module will suffice?

That’ll depend on what you’re trying to do. Typically you would use a DAW (like Ableton) to sequence the MIDI module and to record from the USB audio module.

I recommend the Latch module as an essential one for music. It can be used to halve the frequency of your oscillator, giving you a sub-osc that perfectly tracks the master.

Latch (essentially a flip-flop) can also make the clock-pulse to your sequencer go at half-speed, great for multiple sequences at different rates.

Hi @BenMcLean
I did already many jobs with the arduino in combination with the synth kit.
These include a polyphonic synth, vibrato, LFO, optocoupler to control the filter, etc.
You should find these on my inventions page but I need first to recover these since littlebits changed their website drastically.
Please check on a regular Base since I will often pit new inventions.
Greetings