Tonepad's Digital reverb using FV-1 chip

[mojotron]

Has anyone made one of these - it looks pretty straight forward.

[gvidelock]

I'm in the process of debugging my own version (I created a new artwork with surface mount resistors and decoupling caps).

Right now, the basic operation (guitar -> ADC -> internal move -> DAC -> amplifier) works well. It's a nice, clean, crisp sound. The Tremolo effect (internal program #2) sounds fantastic. But those are the only 2 things I have working so far.

I'm having a problem debugging the Reverb, Chorus, and Flange effects supplied in the internal programs. I'm sure once I figure them out that this will be a nice effect. I have a note on the Spin Semi support forum.

Then I can do some programs of my own.

   ...Gary

[hgamal]

I have some samples of tonepad FV1 project here:

http://www.gamal.com.br/fv1.php

It is written in Portuguese, but the sound talks for itself. I have recorded those samples to demonstrate the FV1 to the www.handmades.com.br community.

I think FV1 is a great chip and very useful. If you do not use a dry-wet control or a parallel effect-out power-in, the built in reverb is useless.

[macombaland]

how do you add a wet/dry to the circuit??

[MetalGuy]

how do you add a wet/dry to the circuit??

You need to add a simple mixer circuit like this for example:

[hgamal]

how do you add a wet/dry to the circuit??

At geofex there is a good article about this:

http://www.geofex.com/Article_Folders/panner.pdf

[hgamal]

how do you add a wet/dry to the circuit??

You need to add a simple mixer circuit like this for example:

This circuit do not permit to get only the wet signal!

Maybe using a second  pot (dual ganged) controlling the signal feeding R4...

[MetalGuy]

This circuit do not permit to get only the wet signal!

No, it doesn't. It's similar to the mixing circuit found in most pedals.
To get only the 100% dry -> 100% wet signal use the panner from the link above.

[gvidelock]

I got my board working last week and have been playing with the sample programs on the web site. I needed to replace the FV-1. I think I zapped it in my non-electrostatically protected environment.

The sound is very transparent. I.e., with no effect running - internal program #5 - pressing the true-bypass in and out, to my ears (through my JC-120), there is no loss of tone. The built-in effects are clean sounding. The tremolo is definitely one of the best features (I have a homemade Tremulous Lune to compare to - I like the FV-1 better right now).

I haven't tried any programming on my own yet, except to modify parts of the code from the website. I did use the code snippet suggested in one of the tutorial pages that creates a distortion and it is subtle and smooth.

I agree that it needs an external mix for the original signal. My next board design will have one.

[mojotron]

What do you need to program it - I saw a reference board with a USB interface, but found nothing on how to get a development board. Anyone know where to get a development board/interface?

[MetalGuy]

Anyone know where to get a development board/interface?

Check out the distributors listed on their site.

http://www.profusionplc.com/products/SPN1001-DEVB.html

[mike_a]

Hi all,

I'm also interested in the digital reverb project.
I saw on the spin website that there are other open-source reverb algorithms with extra controls (like plate-reverb etc.).

Does anyone know how I can download these to an EPROM like the 24LC32?
Are there any "universal" EPROM programmers or is it only possible withe the SPIN dev board?

Also, if there is anyone who can send me an already programmed EPROM with these presets - I am willing to pay.

Thanks!

[snap]

did you find the forum over there?

[mike_a]

yeah, but it's not that "active" if you know what I mean....

also, I guess that they will tell me to buy the dev board there.
I don't want to spend a lot of money on the dev board, as I'm not developing anything.

[octfrank]

yeah, but it's not that "active" if you know what I mean....

But if you actually looked, you would see I try to respond to every message posted. Some I need to talk to Keith about first (RG's questions on reverb for instance, I have sent them to Keith, no reply yet.) How active is not a measure of the quality of a forum.

also, I guess that they will tell me to buy the dev board there.
I don't want to spend a lot of money on the dev board, as I'm not developing anything.

And if you had posted or emailed Spin or OCT, or even just d/l the FREE assembler you would have seen it will save to Intel HEX format that almost every universal programmer can read so you could program a 24LC32A and not needed to purchase the development system.

[octfrank]

(RG's questions on reverb for instance, I have sent them to Keith, no reply yet.) How active is not a measure of the quality of a forum.

Oops, Sean's question, not RG's.

[mike_a]

yeah, but it's not that "active" if you know what I mean....

But if you actually looked, you would see I try to respond to every message posted. Some I need to talk to Keith about first (RG's questions on reverb for instance, I have sent them to Keith, no reply yet.) How active is not a measure of the quality of a forum.

also, I guess that they will tell me to buy the dev board there.
I don't want to spend a lot of money on the dev board, as I'm not developing anything.

And if you had posted or emailed Spin or OCT, or even just d/l the FREE assembler you would have seen it will save to Intel HEX format that almost every universal programmer can read so you could program a 24LC32A and not needed to purchase the development system.

I apologize if it came across as disrespect to you or the forum.
It wasn't my intention.

After your post I went over there to look and I see that you are right.

Thank you for your answer and sorry again.

[Sonic]

I'm in the process of debugging my own version (I created a new artwork with surface mount resistors and decoupling caps).

Right now, the basic operation (guitar -> ADC -> internal move -> DAC -> amplifier) works well. It's a nice, clean, crisp sound. The Tremolo effect (internal program #2) sounds fantastic. But those are the only 2 things I have working so far.

I'm having a problem debugging the Reverb, Chorus, and Flange effects supplied in the internal programs. I'm sure once I figure them out that this will be a nice effect. I have a note on the Spin Semi support forum.

Then I can do some programs of my own.

   ...Gary

Did you find out what was wrong with the Reverb, Chorus and Flange part of the effect? I'm having similar difficulties with the effect, but my problems is getting the Flange and delay/pitch to work (pitch on it's own works well).

[slacker]

I don't know if this is the problem, but Delay/pitch is a stereo effect, the delay is on one side and pitch on the other, so you need to use both the inputs and outputs.
If not all the effects work it's probably a bad connection to one or more of the S0 to S2 pins.

[Sonic]

I don't know if this is the problem, but Delay/pitch is a stereo effect, the delay is on one side and pitch on the other, so you need to use both the inputs and outputs.
If not all the effects work it's probably a bad connection to one or more of the S0 to S2 pins.

Thank you I found out it was a combination of only using one channel and under voltage, I had a voltage drop down to ~2,6V which for some reason don't egnage the flanger