pt2399 noise. solution?!

[otsismi]

I built the cave dweller but can't box it up with all that noise. People have good results from the sea urchin?

[RobA]

[...]

How can you filter out the noise but maintain fidelity?

I don't think it's possible. Maybe with a compandor and a light amount of low-pass filtering, but it's a pain in the ass.

The Biyang "Analog" Delay uses an SA571. I can't say that it does anything for the fidelity of the audio. My guess is that  it's only in there because it was in the BBD circuit that they lifted the design from. The pedal isn't bad, but there is nothing special about the quality of the audio. It's nowhere close to my DL-8 for example. It's comparable to all of the other PT2399 delays I've played with.

[culturejam]

The Biyang "Analog" Delay uses an SA571. I can't say that it does anything for the fidelity of the audio. My guess is that  it's only in there because it was in the BBD circuit that they lifted the design from.

You can't make a 2399 have high fidelity. It's just not part of the design (the max bandwidth is crappy to start with). The best "hi fi" tone you'll ever get out of one is at about 250ms. Beyond that, you just have to accept it's going to be either noisy or heavily filtered.

It's nowhere close to my DL-8 for example.

And it shouldn't be. That's a very apples-to-pineapples comparison. The DL-8 has a heavy duty DSP engine under the hood. It's like comparing the Millenium Falcon to a '72 VW Beetle. 

[GrindCustoms]

NE571-SA571 will help...

After sorting out bunch of PT's to get the cleaner one i was able to get rid of the inherent «pshhhht» after repeat with delay times around 400ms....after that it was coming back but less loud...

The core delay circuit i was using with the compander is the DeProfundis Delay that CJ designed and that is HIGHLY filtered....

I'll dig out that bunch of wire....and try that «revelation»...

[RobA]

[...]

It's nowhere close to my DL-8 for example.

And it shouldn't be. That's a very apples-to-pineapples comparison. The DL-8 has a heavy duty DSP engine under the hood. It's like comparing the Millenium Falcon to a '72 VW Beetle. 

True except for the point that, since the Biyang delay I have was branded as an Akai pedal, the original list price of the Biyang was actually more than the Hardwire (not that I actually paid anywhere near that much for the Biyang).

It would be very interesting to know what is in the Hardwire pedals. I can't tell from mine because the chip is a custom branded SoC.

[culturejam]

Yeah, the RV-7 I have says "AudioDNA - Harmon" on it. I know Harmon is the parent company of Digitech/DOD, so maybe it's something they actually developed. Who knows?

[kothoma]

Yeah, the RV-7 I have says "AudioDNA - Harmon" on it. I know Harmon is the parent company of Digitech/DOD, so maybe it's something they actually developed. Who knows?

Isn't that Harman?

[RobA]

Yeah I think it is Harman.

They are a big company with lots of digital audio sub-companies, so I suppose that it is possible that it is something entirely their own design. But, I always figured that it's based on at least some other company's core FPGA, DSP, or MCU with someone else's AD/DA bolted on to it on the chip. Either way, it certainly does make for clean hardware design in all their digital pedals.

The main reason I was interested was that I've been hoping to find a DSP or MCU with an attached CODEC just to make the whole hardware side of doing digital DIY pedals simpler.  I haven't been able to find anything yet. (Well, except for one from Cirrus-Logic, but I don't like the programming environment limitations.)

[kothoma]

The main reason I was interested was that I've been hoping to find a DSP or MCU with an attached CODEC just to make the whole hardware side of doing digital DIY pedals simpler.

Now that would be great!

[culturejam]

The main reason I was interested was that I've been hoping to find a DSP or MCU with an attached CODEC just to make the whole hardware side of doing digital DIY pedals simpler.  I haven't been able to find anything yet. (Well, except for one from Cirrus-Logic, but I don't like the programming environment limitations.)

So the Spin FV-1 or Cool Audio V1000 don't meet the requirements? I'm very new to the digital side of things, so excuse my ignorance if that was a dumb question.

[RobA]

It depends on what you want to do. I'd say the Spin Semi FV-1 would be usable for some effects, but the things I want to replicate from my software based effects (AU's) need more computational power and RAM. I haven't looked much at the Cool Audio chip because I thought the programs were fixed and I think it still needs an external CODEC.

What would be ideal for many of the effects I want to do would be a Cortex-M4F with an integrated ADC/DAC.

On the good side of DIY digital effects, the Arduino Tre is going to be released in the beginning of 2014 and it's supposed to have both an Atmel MCU and an Arm Cortex-A8 with stereo audio I/O on the board. I'm not sure how big it's going to be yet or what the price is, but it's going to be usable for at least some audio applications.

[kothoma]

On the good side of DIY digital effects, the Arduino Tre is going to be released in the beginning of 2014 and it's supposed to have both an Atmel MCU and an Arm Cortex-A8 with stereo audio I/O on the board. I'm not sure how big it's going to be yet or what the price is, but it's going to be usable for at least some audio applications.

Yes, the Tre looks promising. Let's see if the audio system will be good enough for realtime. But could inspire great projects nonetheless. Guess it is >US$100.

[RobA]

[...]
Yes, the Tre looks promising. Let's see if the audio system will be good enough for realtime. But could inspire great projects nonetheless. Guess it is >US$100.

I'm guessing it's going to be more like US$50. Since it's basically a BeagleBone Black mixed in with an Uno I think they can do it for around there. I need to look into it more to see how the audio is set up. I think that's going to be where the big questions are. I'm hoping that they've got some I/O pins that give direct access to the CODEC.

[kothoma]

[...]
Yes, the Tre looks promising. Let's see if the audio system will be good enough for realtime. But could inspire great projects nonetheless. Guess it is >US$100.

I'm guessing it's going to be more like US$50. Since it's basically a BeagleBone Black mixed in with an Uno I think they can do it for around there. I need to look into it more to see how the audio is set up. I think that's going to be where the big questions are. I'm hoping that they've got some I/O pins that give direct access to the CODEC.

Can't find any details anywhere.

[RobA]

Nope, me either. And, the audio is different on the BeagleBone Black, so looking there isn't any help either. It looks like we'll have to wait for more details. The one thing I have figured out by looking at the photos is that the board is going to be bigger by quite a bit than the Due. That's unfortunate really.