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Hello, As recommended in the capacitive sensor library’s reference (https://www.pjrc.com/teensy/td_libs_CapacitiveSensor.html), I’m using wall power for teensy. It’s basically a phone USB charger. However, the charger doesn’t have the third ground connection. I couldn’t really find a lot of...

I recently bought a Ground Loop Noise Isolator: https://www.amazon.com/dp/B06XQYN77L?ref=ppx_pop_mob_ap_share I’m guessing that using this with the headphone jack on the audio shield of teensy should overcome all ground related concerns.

Wonderful! What a coincidence that this is happening exactly when I’m looking to buy! Just out of curiosity, how was this timeframe chosen by spark fun?

Hello, I’m looking to order lockable teensy 4.1 NE in bulk. However, it’s shows ‘back order’ on spark fun. which has been the case for a while now. Any idea on when it’ll be back in stock? Is there a way to buy it elsewhere? Thanks, Tejas

Hello, I’m trying to accomplish serial communication between teensy and iphone using usb C. What’s the best way to achieve it? Thanks, Tejas

I checked with a spectrum analyzer. There is indeed a DC offset. I don’t know how to fix that though. Any help is appreciated! I have attached the .h file here.

I mean variable triangle or asymmetric triangle. Since these argument options for the waveform object aren’t band limited, I looked up on how to create them using a band limited pulse. Update: Just yesterday I asked Claude to do the work for me, and it did! Though, I’m not sure if it did it in...

Hello, I'm trying to create an band-limited triangle with 0.25 duty cycle. For that, an approach that I came across uses a band-limited pulse wave with proper DC offset and a 1 pole lowpass (an integrator). Though I understand this conceptually, what is the best way to implement this in teensy...

Hello, I have a teensy 4.1 whose stereo line out is connected to a mixer, which is connected to (and powered by) a laptop (running on battery) via USB. The teensy is also connected to the same laptop via USB to monitor serial messages. Headphones are connected to the mixer. I hear a constant...

I'm doing a sweep of level in amplitude(level) of the waveform object. I expected a smooth increase from 0 to 1. However, the amplitude sounds like it is increasing in steps, especially between 0.0 to 0.1 range of input level. Is there a way I can increase the 'resolution' of the sweep? I tried...

Thanks for this! My application however needs a variable frequency and a variable duty cycle triangle. Since the duty cycle is not always 0.5, I can't rely on the inbuilt WAVEFORM_TRIANGLE_VARIABLE, as around 0.0 and 1.0, the aliased frequencies will be quite audible.

Makes sense. What is the easiest way to create an anti-aliased triangle waveform in teensy?

Got it. I am using the audio shield with teensy. A google search revealed that the shield performs anti-aliasing during DAC. In that case, what is the purpose of using using band limited waveforms at all?

I noticed the word ‘BANDLIMIT’ in the names of certain waveforms, but not in the triangle ones. Are they anti aliased?

With line out from teensy to channel 3 of the amp, I’m setting both CH3 and master to 50%.

Update: I have connected line out, which works great!

Thanks for going through the amp specs! Here is my sequence of things to do (when teensy is on battery power). Please correct me. 1. Set sgtl5000 volume() to 0.5. I like to keep it fixed for my application: 2. Connect teensy audio shield headphone jack to aux in on roland and set its level to...

Thanks for the clarity! There are situations when I am completely on battery (both teensy and roland). I’d be glad to use the headphone jack for those occasions. What should I keep the sgtl5000 volume() to in that case? I’ve been keeping it at 0.5, but would like to optimize that for best audio...

I can potentially solder an output jack directly to the audio board. The board, however, has two of the nine pins unnamed. I’m assuming they are ground. The amp data sheet states input level as -20 dBu. However, its own line out is rated at +4 dBu. I’m not sure what the standard for line level...

Also, how should I decide the value for lineOutLevel()? I can keep it at default, but want to understand how that's decided.

I'm convinced. Now, for connecting the line out, I have found this AC97 on amazon. https://a.co/d/e158eOy Would the output jack on this work as such (without any modification)? This should be the standard connector for PCs.

Hello everyone, Is there any advantage of using the audio shield's line out over its headphone jack for connecting an external amplifier? I've been using the headphone jack for this purpose so far, with sgtl5000 volume() set to 0.5, and have not had any trouble with my external amp (Roland KC...

Thanks for the directing me to that thread! I glanced through it and realized that the issue is somewhat beyond my bandwidth at this point.

I get it. Is there a practical way to avoid the artifact though? Why do USB speakers in general not have this problem? (Teensy is acting like a USB interface here.)

That makes logical sense to me. However, the sampling rate is 44.1kHz at both ends. Do you mean that there might be a slight difference even then? It reminds me of an experiment that I did once when I played a sine of 440 Hz on two computers, and there were audible interference beats (though...

Yes, but the reason I was asking is that the audio from Teensy without any equalization didn’t sound the same as that from the computer.

There is no nearby phone nor is there an SD card on Teensy. The artifact sounds like a glitch. Let me share a recording.

That helps. Yes, I’m referring to sgtl5000. Thank you!

Hello, I have noticed that the audio output sounds different from the headphone jack on the audio shield of teensy, as compared to when it is sent to a computer to record and play. I’m using the 7 band parametric eq function in the code. I’m guessing that it works only for the headphone output...

Hello! I’ve noticed that my audio sounds clipped after raising the levels of the 7 band parametric eq. As a best practice, what should I keep the overall amplitude of the audio so that it doesn’t clip even after all the eq parameters are max? Thanks in advance! Tejas

Hello! I’m using teensy as a simple audio output device for my computer. It works fine. However, after every few seconds I hear an artifact which sounds like a scratched CD (compact disk). I’m not sure of the cause. Any ideas to fix it? I can share code/audio if needed. Thanks in advance! Tejas

Anyone having an answer to this?

Thank you, @MarkT and @manicksan! I'll give this a try and get back if I'm stuck.

Hello! I am trying to create a waveform that resembles the recorded sound of an organ. I see two options for doing that. 1. Using arbitraryWaveform(): I would open the recorded sound in audacity and export one wavelength as text data. This is between -1 and +1. I have three questions in this...

Hello! I have noticed that increasing the dBgain in calcBiquad() beyond a certain point leads to audio clipping. That point is different for each of the 7 filters. Is there a way to avoid the clipping? My output signal gain is 1. If I reduce the gain a little, the clipping stops. However, I...

That did the trick! Thanks for the suggestion. :)

The signal is going through the granular object, and I do hear it the moment I comment the following line. However, when the line is uncommented, I hear nothing. Here is how the flow looks.

Hello! I am trying a simple project where I want to change the pitch of audio from mic input of Teensy audio shield, and send it out via the headphone jack of the shield. My code is attached. I am unable to hear any audio. However, the moment I uncomment the only line in the loo(), I can hear...