Loop delay pedal with RV-1, PT23xx, Holtec, coolaudio chips ,etc....

[valvusmusicus]

Has anyone ever thought of programming, especially the SPin FV-1, to be a loop delay. I'm sure its possible to get over a second of loop time, with a decent bandwidth and quality for Bass or guitar.This would be a true loop effect(not infinite feedback type effect) like the Boss loopers
I'm truly stuck in the analogue world, and think this would be a good intro to Digital.
Any pointers to where I should start/research please??

[Digital Larry]

Slacker has already programmed the FV-1 as a tap-tempo delay, and if I get you correctly, you don't want to hear the delay unless it is actually in the looping mode?  Seems possible.

The FV-1 has a steep learning curve, so maybe someone who's done this already will jump in.  I'm pretty familiar with the FV-1 but I haven't done this and am not spending a lot of time on it recently.

Regarding getting > 1 second delay on it, there are ways to do it but you'll have to bring the sample rate down, which at some point will result in aliasing unless you add external low pass filtering.

[cloudscapes]

The problem for me with the FV-1 is the lack of inputs. A looper traditionally needs an input to tell it when to stop recording and to start looping. As far as I know, the FV-1 has no such button/switch inputs. There are the three pot inputs, maybe four if you use one of the audio ADCs. Then again, I haven't had my morning coffee yet, so I may be wrong.

I've been building a looper/delay, though with a microcontroller.

[Digital Larry]

It's possible to connect a switch and pullup to one of the FV-1's 3 analog pot inputs, which can then be interpreted as high or low.

[free electron]

Or, if mono is an option and you need an ultra fast response: use an oscillator to generate a waveform, gate it and feed it into one ADC input. I will cost you a few instructions in the DSP program to ABS one channel and compare the envelope with a threshold, but here is your on/off switch. I have done that using one  PWM output on a secondary microcontroller. Set the PWM to 50% = ON, 0% = OFF. 

[valvusmusicus]

Hi There
Yes, Free Electron, why didn't I think of that, brilliant! And a big thanks to all others who replied, will go away, have a play and post results!

[slacker]

There's a very simple FV-1 loop program here http://www.spinsemi.com/forum/viewtopic.php?t=20 using a switch like suggested above instead of or as well as pot0 will allow you to start/stop playback/record. This is basically the same a the "hold" function on Boss DD3s and the like.
There's another version of it here that adds control of the delay time http://www.spinsemi.com/forum/viewtopic.php?t=161&start=30&postdays=0&postorder=asc&highlight=

You can also do delay effects where maximum delay level gives looping playback, if you want to do anything much more complicated than this then the FV-1 probably isn't the right tool for the job.

[valvusmusicus]

What I want to do is, well, what Jaco Pastorius did. He used his MXR 113 blueface delay to set a loop going, I guess with feedback set to max....not sure. Then would switch the output of his bass into another clean channel on his amp and play along to the loop, with a non-effected bass.
seems to me you would get cleaner results using a loope, then the backing loop wouldnt dsgra2de. STill not sure how he does it

Thanks again for the replies

[krister]

Use a digital delay like the Nova Repeater. An A/B/Y box that allows both inputs to be on like the whirlwind selector. I have done this with Nova Repeater without an A/ B/Y box by turning spillover on with the feedback all the way up. When you turn off the delay it keeps going because of the spillover function. Then you can play over it. The A/B/Y box would give you more control. You would need a Y cable coming out of the output of you bass or guitar or two output jacks.