Payback v2.0 Feature Requests

[Jaicen_solo]

That sounds like a great solution Andrew. I guess it's not much of a saving in terms of IC real estate, but i'm guessing there's substantially fewer passive components? I know on my stripboard layout, half the board is taken up by the quad op-amp and associated parts.

I'm assuming you've jettisoned the multiple loops option, but does your controller IC handle vibrato or is that still CMOS?

I'm going to push ahead with V1, because I can source 2560's  and I want to try multiple loops, but can you give us any idea if V2 will land any time soon?

[The Tone God]

That sounds like a great solution Andrew. I guess it's not much of a saving in terms of IC real estate, but i'm guessing there's substantially fewer passive components? I know on my stripboard layout, half the board is taken up by the quad op-amp and associated parts.

I'm assuming you've jettisoned the multiple loops option, but does your controller IC handle vibrato or is that still CMOS?

I'm going to push ahead with V1, because I can source 2560's  and I want to try multiple loops, but can you give us any idea if V2 will land any time soon?

The real easte savings is more in that with the dual opamp there is more space for normal parts, less need for sticking parts under ICs like I did with the perf boards. I did kinda go overboard with the v1.0 analog design. v2.0 doesn't have the final level control, you can control the volume of the playback but the straight signal is unity on the output. I would say its about half the parts of v1.0.

Multi loops are gone. Too much delay switching between loops. Its an issue with the ISD and not the uC. Yes the vibrato is done with uC. All the CMOS is gone and replaced with the uC with only the need for a handful of parts. There is also some debugging facilities in the uC to help with problems when building to make sure it is hooked up to the ISD correctly.

I have been switching between commercial and DIY stuff. I did the plates recently so now I'm working on a new commercial product. I'm hoping to have it out in a month. Then its time to get back to a DIY project and Payback is next on the list. Its so close to being done its starting to irritate me every time I'm at the work bench with it sitting there in the corner.

Andrew

[Jaicen_solo]

I must say, i'm excited to see what you've come up with for this new looper. I'll certainly build one, I can't get enough of loopers.
When you say the straight signal is unity, does that mean that the record level is gone? I would think that would make it harder to dial in the right level if you're putting pedals in front of the looper?
Did you post the larger schem yet? I'm still having trouble verifying my vero design with the small full schem.

[The Tone God]

I must say, i'm excited to see what you've come up with for this new looper. I'll certainly build one, I can't get enough of loopers.
When you say the straight signal is unity, does that mean that the record level is gone? I would think that would make it harder to dial in the right level if you're putting pedals in front of the looper?
Did you post the larger schem yet? I'm still having trouble verifying my vero design with the small full schem.

No the record level is still there but on v1.0 there was a control to set the final level output level that included the straight as well as the playback signal. That is gone. The straight signal is now set a unity at all times. The controls that are in v2.0 are record level, playback level, playback tone, fidelity, vibrato speed, vibrato depth. The pot wiring will also be easier in v2.0.

Just found it, here is that larger schematic for v1.0:

Large Payback v1.0 Schematic

Andrew

[Jaicen_solo]

Thanks Andrew, should have waited for that it would have made my work a bit easier.
So far, i've got the audio and logic stripboard done. It measures 40*11 holes, so it will easily fit into a 1590b, and hopefully if I use 9mm pots, that will allow me to put the ISD daughterboard on top of that.

Back on topic, I can assume that the ISD output of V2 is still set at a higher level than the straight signal and can be turned down using the playback level? Fidelity sounds interesting. I assume that it's a pot to drop the speed of the clock for lower sample rates?

[The Tone God]

Back on topic, I can assume that the ISD output of V2 is still set at a higher level than the straight signal and can be turned down using the playback level? Fidelity sounds interesting. I assume that it's a pot to drop the speed of the clock for lower sample rates?

Good work.

Correct about the controls. You can either increase the input, even to overdrive the ISD for distortion effects, then pull it down with the playback control or drop the input if it is too hot for the input of the ISD and bring it back with the playback control to match the straight through signal. So both the record and playback level controls have gain to them.

Yes the fidelity controls the clock rate so you can set it to what you like or change it during playback to do pitch shifting.

Andrew

[aziltz]

very excited about this!

[Jaicen_solo]

Me too, just give me ten days to finsh my V1 though

[alparent]

Is there a V2 schematic out there yet?

[The Tone God]

Is there a V2 schematic out there yet?

Not quite yet. I'll probably be getting back to it in a couple of weeks. Things are starting to level out around  here.

Andrew

[Valoosj]

Any news on the V2? Really looking forward to this.

[Taylor]

I suspect TTG knows there's a lot of anticipation, and will let us know when there's any info on the project, so probably no need to keep asking. He's too polite to say, "quit bugging me" so I'll say it for him. 

[The Tone God]

I thought I would have had a couple of weeks during the season but I got hit with touring clients, then people who wanted a surprise job for xmas gifts, then the holidays themselves so I didn't get a chance to break away. Plus I think there is an issue with the bypass that I thought I had solved. It is sitting there on the bench. I just need to clear all the jobs that are around it.

Andrew

[Jaicen_solo]

Just a quick bump to see if Andrew has made any progress?
FWIW, my v1 is still unboxed and has been giving me niggly problems for the last few months, and is sat on my desk surrounded by other half finished projects...

[The Tone God]

Yes I have worked on it here and there. One of what I thought was a minor issue ended up being a bigger issue due to the design of the output. I do have a fix that works but it does add alittle to the circuit complexity.

A bigger situation has arisen though. There is a chance that the DIP version of the ISD IC that v2.0 uses maybe discontinued (it looks like the SMD versions will stay) but this is not confirmed or announced yet. While there is still plenty of stock around of the DIP version I don't want to have what happen with v1.1 again where the DIP version of the IC was halted and only the SMD version is in production. With that in mind I started to think about something else.

The original plan was to offer a pre programmed ICs that would do all the interfacing to the ISD IC. With the possibility of the DIP discontinue along with the some of the complexity of the digital portion of the circuit I thought about offer a pre constructed board that would have the ISD, controller, and support circuitry all put together and tested. The audio design would still be up to the builder to construct but the current design only needs a single dual opamp. I would make it with SMD parts so it could be smaller and leave the board design open to modifications. Its just a thought I'm playing with.

Andrew

[zed.zeppelin]

Wish there were more news about this. 
I think I'll do Jaicen's veroboard version of the V1, meanwhile.
You have some nice work in here, Tone God. Congrats!

[alparent]

Yes I have worked on it here and there. One of what I thought was a minor issue ended up being a bigger issue due to the design of the output. I do have a fix that works but it does add alittle to the circuit complexity.

A bigger situation has arisen though. There is a chance that the DIP version of the ISD IC that v2.0 uses maybe discontinued (it looks like the SMD versions will stay) but this is not confirmed or announced yet. While there is still plenty of stock around of the DIP version I don't want to have what happen with v1.1 again where the DIP version of the IC was halted and only the SMD version is in production. With that in mind I started to think about something else.

The original plan was to offer a pre programmed ICs that would do all the interfacing to the ISD IC. With the possibility of the DIP discontinue along with the some of the complexity of the digital portion of the circuit I thought about offer a pre constructed board that would have the ISD, controller, and support circuitry all put together and tested. The audio design would still be up to the builder to construct but the current design only needs a single dual opamp. I would make it with SMD parts so it could be smaller and leave the board design open to modifications. Its just a thought I'm playing with.

Andrew

Or use a SOIC to DIP Adapter 28-Pin

[miique]

Any updates on 2.0? 

[The Tone God]

Hello!

I should let know where things stand with this project as there has been a lot of recent interest in the Payback again. Basically things have gotten more complicated from many angles.

When I went to try to finish up the design I found that some of the outstanding issues were going to require more hardware making things more complicated. I decided I would offer a pre assembled Payback module that would be tested, smaller, and easy to use for the DIYer. The module would not have the audio sections so the DIYer could still decided how to use it but all the power supply, control logic, ISD, etc. would be on the board allowing for simple hook up. I would have still offered the Payback controller in DIP form for those interested in doing something different.

Then I found out the DIP ISD1700 is officially being discontinued. Once the stock of DIP parts are gone there will only be SMD versions. I was now looking at the same situation as the v1.1 / ISD1600B which I did not want to happen again. This made me wonder if I should continue with this design direction. The only DIP ISD versions left are not suitable for our needs and I doubt anymore are coming. The writing is on the wall, DIP versions of the ISD series are being phased out for SMD versions. This made me think that trying to offer a DIP / DIY hack friendly version is not going to be possible.

With that said I think there is a stronger interest for a pre assembled module then at DIY hackable version. By removing the DIY hacking constraint the design can change. To that end there are better ISD models that would be better suited for that need. So now I think I will offer a pre assembled Payback module with a controller providing a DIY friendly interface.

So that is where things stand now. Payback v2.0 will be a pre assembled module you can purchase that will be ready to play with.

Sorry for not keep people informed of the progress. As you can see I have been resettling with issues on this too long project.

If you have any questions or suggests feel free to post and I'll answer the best I can.

Andrew