Search results

Happy with the QA analyser? Have wondered about ordering one..

Might be able to help you=) seny you DM

Thanks for the quick answer! Then I'll give it a try and see if its doable. Think a Quad I2S input object would be the outcome of this. TBC..

In the description of the I2S in/out slave objects it is stated that only one input/output object is allowed. I suspect that is because the audio engine can't run at two different clocks. But what if I connect two I2S streams from a source that has the same clock? Would that work? Of course...

I tried to find the files for this project that I think should be in the first post in this thread. But it does not work for some reason. Can you point me in a direction where to find this? ..if you are still willing to share..=)

I see. yes it is a lot to cover there, but I think you got a good start with the low noise front end=) But I would recommend to read this thread: https://forum.pjrc.com/threads/42678-Teeny-Guitar-Audio-Board?highlight=guitar+effect Covers the most of it I would say. Blackaddr also sell the board...

you're welcome=) as guitar effects usually needs a huge dynamic range I have ended up with using the AK4558 codec. That has lower noise and works great. The SGTL5000 is a good chip, but is best suited for handling line level signals.

Yes, I have seen that instruction. I actually think they read this post and just put in the mod thinking it would benefit on the standard teensy audio board. I don't think it will. but hey, just ask=)

This mod was on a board I made myself. And probably an issue of some layout stuff. Don't think it will help anything on the teensy audio board..

I know you wrote that you disconnected the supply to the leds. Are you sure? I had a lot of nasty noise from those LEDS influencing other signals nearby. Ended up with a 2200uF cap on the 5V supply to the leds. That killed the noise.

I am running my code on Teensy yes. At the moment I am working on the HW on my project, but I will investigate this further when I get to the programming again and publish the results here.

Seems like this is dithering? As dithering use a random signal injected into the filter. And the lowest bits are random(the noise floor) it should be about the same. But maybe worth a try to use white noise instead? I don't fully understand the code, but is this feedback on every stage inside...

Hi, I found out the same a little while ago... I think it is something called limit cycles. It is present when the input to the filter is very low. The filter itself will make the noise. With fixed points it will be a quite uniform/stable noise. But if you use floating points it will jump up...

I actually did some measurements on the sgtl5000 on this topic. It is on my own board, with some circuits in front of the codec. Just to get a wider dynamic input range(for guitars/bass). But the important thing is not the absolute value of the measured noise(which is my main goal to get as low...

Did you manage to get it working?

I often use the DC object and multiply it with the signal. The DC object has the option to set the time the change in value should be gradually changed over. amplitude(level, milliseconds); But as Thyratron said, it would be nice to have that inside the mixer... might look at that one day..

Good to hear! Would love to see what you can get from this. And yes, you should disable the "nintendo" sounds=) And you might want to mix the pitched voice with a bit of the original to get the right attack. Do you get some ticking artifacts in the sound from the delay line? This comes from when...

Yes... I took out some code to clean it up a little, but I removed too much=) Put this array into the code after the ArbWave: int16_t DelayWave[256] =...

Yes, I used a delay object made by Byron Jacqout at Sparkfun. This object has a input for a modulation signal i.e the input determine the length of the delay. And then I feed that input with a triangle wave. Then the pitch will change up or down dependent of the direction and frequency of the...

Yes it is possible. You don't specify what type of display (i2C or SPI) you are going to use. But I have used I2C and connected it to pin 18 and 19. Works fine with the Adafruit_SSD1306 library.

Good to hear that you figured it out=) From your code I see one important improvement: In your void setup() you should disable the HP filter in the codec. It adds some nasty noise.. sgtl5000_1.adcHighPassFilterDisable();

sounds very promising yes! To be able to measure the impulse response is the key to any "black box" my teacher used to say=) Will try to play around with your code when I got some spare time... Didi you build the codec circuit yourself or is it on a pre fabricated board?

ohh! Thats some nice code=) This gives a lot of opportunities indeed! And how does it sound compared to a real tube amp?

Good work! Seems like you did a very good job with this. From where did you get the tube data?

Thank you both! That works perfectly =)

I have a question... I am trying to extend chipaudettes compressor class with an option to add another input and use it as a sidechain compressor. Where one of the inputs are analyzed and the other input gets the compression based on the analyze. But the program freeze when I try to read the...

I absolutely understand your arguments. I also like it as clean as possible when it comes to GUI, but it's hard when it comes to stuff like this. Audio Weaver got over 400 blocks, so as long as it is structured well it can work. Really looking forward to the new stuff coming in the audio lib!

Ok, I drop the first suggestion. My main programming language is LabView, so I have a tendency to think in wires all over. Maybe too much.. So the tap tempo thing should be done in the code outside the audio core. But the second suggestion you are spot on: I think it would be less confusing...

Thank you @Blackaddr for bringing up these topics! Will also influence my next revision of my pedal input board=)

Yes I have to read my books too here=P You are right about the open loop gain. I had one zero too much. TI specifies the typical gain to 100V/mV. To be honest, I started using the NE5532 many years ago in my pedals because they had a good reputation for audio, low noise, low price(relative) and...

thanks! Its a 128x64 OLED screen. Nice and easy and lights up well. Actually better then what the picture show https://www.pjrc.com/teensy/td_libs_SSD1306.html And quite cute=)

I love the compressor you made chipaudette! I used some of the code in this one: For my use, I didn't needed the Pre gain calculation. Thats up to the user to decide in this case. But I really like the floating point lib and the functions! Here is the code...

The input impedance of an opamp is dependent of the configuration. In a non-inverting configuration the input impedance is defined as: (1+A0*B)*Zi Look at this link: http://electronics.stackexchange.com/questions/177007/input-impedance-of-a-non-inverting-op-amp So if you have a voltage...

whats the pitch on the teensy 3.6?

or this codec from ti: http://www.ti.com/lit/ds/symlink/lm49352.pdf 1.27USD if you buy 1k.. And -46dB to +18=)

Nice! Like the microMIDI box! You are absolutely right in that the signals can get very high on many stompboxes. But it seems like some of the major players out there stick to the industry standards. Taken from a TC electronics manual: That is around 3.5vp-p. But a active/passive pickup...

Don't you want any potmeters or other inputs for controlling parameters of the effects? Or do you plan to put that on another board? Regarding the input levels, I know that there are some active pickups that operate in the 2V+p-p range, but I think the input range of the SGTL5000 should cover...

I'll split it in two and try to sort my thoughts.. -The first one: Basically the waveform object in the library with an option to assign an Inputpin that can be used to adjust the tempo by tapping the tempo. Typically a momentary switch connected to the inputpin. -The other object I am...

Thanks Paul, will do that.. One more thing; could it be an idea to have a block in the audio lib that can be set up to be a i.e tap tempo block. You assign a pin as input and then it handles the interrupts and gives out a signal like the function generator module. I know it is more flexible to...

I have used the neopixels a lot in combination with audio. Have used pin 3 and 8 as output for the LEDs. And it works. But you should really watch out for noise on the power lines! The best is to have a separate power regulator for the LEDs. The neopixels are nasty and you will get a lot of...

Thanks again. This seems like a good approach to speed up the slow stuff yes..

Thanks KurtE! I will try your way. btw, how long time takes an analog conversion?

I agree that it is not needed to use interrupts on potmeters. But when you want to have an accurate tap tempo it comes in handy. I have up till now made it without interrups, but the accuracy is not good enough then. How would you recommend implementing interrupts without disturbing the audio?

But it didn't.. I put the intToFloat in front of the compressor and the FloatToInt after. But it was only 0 out.. will search more and see if there is another reason=)

Really good work Chip! I have tested the compressor for use with instruments and it works very well! But now I'm in need of a level detector (or envelope follower) for the audio signal. And you have made a very good one in the compressor. So I tried to just do a tweak in your code to get the...

This depends on how many units you will make.. if its one, then you should by the audio shield. If its 10. Do the same. If its 100, maybe design your own card based on one of the supported codecs that exist in the library.

Cool stuff! and a lot of good work!

If you post the code of your program it would help. But if you use a mixer and mix both of them at unity gain, you would probably get some overdrive! Signals will add up and you will hear clipping bacause the signal is too loud. Try to set the gain in the mixer lower. If you put a peak detect on...

How was you pot connected? Whats the max voltage that could have been on the pins? And have you tested a very simple program that just outputs a sine? That can at least give you a hint if there are some HW faults.

Thanks Paul! I am also looking foreward to do more testing with the 3.6. An order for some boards will soon come=)