line-out possibility

[izumitelj]

hi!

this is really good project; it got me laughing and excited when I saw it
apart from that I also see it as very useful metronome for musical practicing purposes.
however, some kind of line-out would be needed for that, and I'm wondering would it be too much of a hack to implement that?

thanx

[layne]

Hey there, thanks for the post! Glad you like the Metronome project, and I have some good news for you. The second version of the Tactile Metronome (TM2) has a simple line-out capability, where it generates a pulse on one of the pins every time it beeps! On the TM2 there's an "expansion header" on the bottom of the PCB, with labels G V B X S P, which stand for ground, Vcc, Beep, eXpansion, sync, and PWM. The expansion and sync pins don't do anything yet, and the PWM is just the pulse-width-modulation output that drives the beeps of the piezo element. Ground and Vcc are straightforward.



The Beep pin outputs an active-low pulse that is normally high, but goes low during each beep. You could use this to drive something external such as lights, motors, external sequencers or synthesizers, etc. Below is a photo of a waveform I just captured of this output.


Every-beep output pin on Tactile Metronome by Mat_the_W, on Flickr

Hope this helps! Let me know if you have any other questions.

[izumitelj]

Hi Layne!

Thanx for indepth reply and good news
I have one more question: Is Tactile Metronome (TM2) already available? I would like to buy it, but on the webshop PCB picture it says 1.0.

Thank you )

[layne]

Oops, looks like I forgot to update the image in the web store to have the photo for the TM2. Thanks for the reminder! I've just updated the image to reflect the fact that we're only selling TM2 kits now (we're all out of the original TM kits). Thanks for your interest! Tactile Metronome 2 Kit

[izumitelj]

arghh ... i just figured out that shipping cost is $35.00 for my country (croatia)! i guess i'll have to build it from scratch.

i'm wondering why so much though. i've recently ordered something from Adafruit via (U.S. Postal Service First Class Mail). weight was 0.32lbs, and shipping $7.90.

thanx

[layne]

Oh weird, sounds like a major issue with the shipping calculator for the web store. I'll look into it tonight or tomorrow morning US time and post again here when I figure it out!

[layne]

Yeah, it looks like the USPS changed their web tools interface over the weekend and it's messing up our store's shipping calculator. International small flat rate box should be like $15 and international first class would be like $5 I think. We'll look into it further tonight after work and get back to you. Thanks for your interest!

[izumitelj]

Oh great
Please let me know when you fix the problem. Thanks!

[layne]

Looks like this problem will require a more long-term fix, so please contact us via the contact form and we'll work something out. Sorry for the confusion!

[izumitelj]

I'm back, now with a tactile metronome

I've started to mess around with it, and now I have more questions regarding line-out implementation. I've connected small headphones on Beep and Ground to see how does it sound. It sounds pretty noisy, there is strong hiss (that changes with tempo changes or when in tap mode), and the contrast between pulse and 'silence' is audibly very small. So that's not very useful out-of-the-box. Maybe that would be good for controlling effects, as a switch or trigger?

Then I've tried PWM and sound was good and usable. BUT when connected that way piezo doesn't respond to taping, and that's also not useful.
Do you have any suggestions how to approach this? I'm thinking about reprogramming microcontroller (I want to make Piezo more sensitive), so maybe solution could come from soft side?

Thanx