Author Topic: FEMTOVERB /Wavefrontsemi/ PCB layout  (Read 69360 times)

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Andre

Re: FEMTOVERB /Wavefrontsemi/ PCB layout
« Reply #140 on: February 16, 2010, 07:10:08 AM »
I have finally finished my Femtoverb which I started to build about 2 years ago.

I also build a PIC controller with LCD to control it and show the chosen preset.

I made a little demo to show the different presets
http://www.youtube.com/watch?v=35whSVXIhn0
The mix pot is in center position.
It is rather noisy and the mix pot acts a little strange as if the wet signal is inverted.


MetalGuy

Re: FEMTOVERB /Wavefrontsemi/ PCB layout
« Reply #141 on: February 16, 2010, 05:05:05 PM »
Quote
I have finally finished my Femtoverb which I started to build about 2 years ago.

Looks nice. I didn't get what was noisy. Mine isn't.
If you use it after some high gain pedal however you'll hear some high frequency artifacts (maybe due to the high sampling rate and resolution) but they can be removed with the help of a simple filter.

Andre

Re: FEMTOVERB /Wavefrontsemi/ PCB layout
« Reply #142 on: February 16, 2010, 06:56:59 PM »

Looks nice. I didn't get what was noisy. Mine isn't.
If you use it after some high gain pedal however you'll hear some high frequency artifacts (maybe due to the high sampling rate and resolution) but they can be removed with the help of a simple filter.

Maybe not in the video I made, but I can hear the noise especially when notes are decaying and it stops when I cut the note.
I will try some extra filtering.
I think I will also change the circuit around the mixpot a little bit.
What I want to try is to let the dry signal pass to the output and replace the mixpot with an effect level pot.
This may not be the best solution for the chorus and flanger mode, but I think it will give more control over the reverb depth without changing the dry note's high
frequencies.
To me it looks like there's a treble cut when I mix in more reverb.

At first I was not too happy about the reverb sounds, but now I've played it with it a little bit more, I'm starting to like them.
I think my final version will be without display but with a six step rotary switch with only the 2 hall reverbs, 1 room reverb and all 3 plate reverbs.
Maybe I will still use a PIC processor to do the Gray codes otherwise I would need a lot of diodes to do so with the switch only.
« Last Edit: February 16, 2010, 07:00:59 PM by Andre »

Marcvv

Re: FEMTOVERB /Wavefrontsemi/ PCB layout
« Reply #143 on: February 17, 2010, 12:49:33 PM »
Hey Andre,

Nice build and nice to see this with the LCD!!

Could it be that you have added some reverb to the sound of the Femtoverb build on the demo? On the rotary preset I hear a reverb wich is not in the preset of the AL3201 as far as I know.

Marc
Transfering graphics onto a stompbox using the Dark T-Shirt Transfer method
http://www.marcvanvugt.com/articles.php?id=11

Andre

Re: FEMTOVERB /Wavefrontsemi/ PCB layout
« Reply #144 on: February 17, 2010, 01:01:44 PM »
Hey Andre,

Nice build and nice to see this with the LCD!!

Could it be that you have added some reverb to the sound of the Femtoverb build on the demo? On the rotary preset I hear a reverb wich is not in the preset of the AL3201 as far as I know.

Marc

Now that you mention it.... yes.
I first used another amp with reverb off, then for the demo I switched to my Peavey Deltablues and forgot to turn off the reverb.
So it's reverb with a bit of reverb.  :D
Maybe I will do another demo with no reverb on the amp.

peterv999

Re: FEMTOVERB /Wavefrontsemi/ PCB layout
« Reply #145 on: February 21, 2010, 10:37:03 AM »
Hey Andre,

Nice build and nice to see this with the LCD!!

Could it be that you have added some reverb to the sound of the Femtoverb build on the demo? On the rotary preset I hear a reverb wich is not in the preset of the AL3201 as far as I know.

Marc

Now that you mention it.... yes.
I first used another amp with reverb off, then for the demo I switched to my Peavey Deltablues and forgot to turn off the reverb.
So it's reverb with a bit of reverb.  :D
Maybe I will do another demo with no reverb on the amp.


Andre, Very much impressed by your Femtoverb and the youtube "show-off"" :icon_mrgreen:

Peter ;)

DIY Bass

Re: FEMTOVERB /Wavefrontsemi/ PCB layout
« Reply #146 on: November 09, 2017, 06:19:17 AM »
OK, I know I am resurrecting a very old thread, but I am probably the last person in the world to have a few sets of the Alesis chips available, and I am about to try and build a Femtoverb.  I am intending to change the PCB layout a bit, so if anybody happens to have an Eagle file for this I would love it so I don't have to redo the whole thing.  Anyone.....?  Please....?