A/DA Flanger does TZF?

[alfafalfa]

Yes ,sure  I would like the exel file very much.

Thanks indeed , Stephen


Alfafalfa

[markusw]

Another Q

Is it possible to mod the ADA Flanger for stereo out (in air mixing)?
Would it work to take the delayed signal from the output of IC1a and to break the connection to the mixing IC 2b? Feedback wouldn't work in case of stereo out I suppose. Any ideas?

Markus

[StephenGiles]

Try taking the delayed signal from different points to see which sounds best.

[markusw]

Try taking the delayed signal from different points to see which sounds best.

Thanks for your answer!
Think I will do some Spice simulations to see how the different stages around the output affect filtering of the signal.

Since Stephen and Charlie suggested to combine the both current ADA Flanger threads:

from http://www.diystompboxes.com/smfforum/index.php?topic=50003.0

If enough folks are interested, I might be willing to do the work and post the layout for review prior to ordering. Any takers?

Thanks for the great offer!
Unfortunately, I think my growing list of mods makes the use of a stock schematics layout pretty difficult. Obviously, some knot in my brain prevents me from building any circuit stock 

So far I'd like to add to the stock version: (not hard to guess from my previous post I suppose)

* TZF option (could be easily integrated by adding two pads for insertion of a second delay line on an add-on pcb)
* For the second delay line one pot for regulating the delay would be cool; I would love to have it mounted to the top pcb but this already would be hard to be impletmented as an option
* stereo out: could probably be integrated relatively easy by tapping the signal off ic1c's out, again just two pads; but probably the delayed signal would need additional filtering for getting rid of residual clock noise, (don't know how much the ic2b stage contributes to clock filtering)  might be done with a small add-on pcb

So I'm not sure whether it would'nt be better to design a layout around my wish-list.


Any comments are highly appreciated 

Regards,

Markus

[StephenGiles]

Read this before you do any layout!
http://www.diystompboxes.com/smfforum/index.php?topic=25380.msg166584#msg166584

[markusw]

Read this before you do any layout!
http://www.diystompboxes.com/smfforum/index.php?topic=25380.msg166584#msg166584

Thanks for that link!!!!! Already bookmarked, copy/pasted-saved, backuped..........

[moosapotamus]

Excellent link, Stephen! We're rockin' now...

Marcus - Sounds like the mods you are interested in just require a few extra pads on the board, yes/no? So, probably a nice option for those who want to "experiment". I'm still down with it... Have you started laying anything out, yet?

I've been messing with bill bergman's powerpoint layout, tweaking colors and resolution to try to make it a little easier to see. Next, I was going to trace through it with Stephen's schematic to see how they match up.

Separating clocks and audio, adding ground planes (on both sides) is of course all totally doable on a fabbed PCB.

~ Charlie

[StephenGiles]

"I've been messing with bill bergman's powerpoint layout, tweaking colors and resolution to try to make it a little easier to see. Next, I was going to trace through it with Stephen's schematic to see how they match up."

Heeeeeeeeeeeeeeeeeeeeeeeeeelp.......I'm going on holiday!!!

[moosapotamus]

Have a nice time, Stephen.

~ Charlie

[StephenGiles]

I wish!

[markusw]

Marcus - Sounds like the mods you are interested in just require a few extra pads on the board, yes/no? So, probably a nice option for those who want to "experiment". I'm still down with it... Have you started laying anything out, yet?

Hey Charlie,

I'm still planning. Also I want to compare rev3 and rev4 by doing Spice simulations. The sims hopefully also will reveal whether additional filtering for the stereo option is needed. Adding the pads for the stereo out option shouldn't be a problem. Don't know whether it would be of interest for you to e.g. have an additional filtering output stage for the stereo option included into the layout/design. I fear it will take quite some time until I could start with a layout or at least provide you with my suggestions on the mods.

Re the TZF option: the pads could be easily integrated. Adding the additional delay pot for the fixed delay to the main pcb (assuming that the fixed delay is on a second board) probably could be done, but in case of not using the TZF option the 5 "standard" pots would be distributed assymetrically on the board. The other possibility would be to have the 5 pots as they are and add the fixed delay pot somewhere else to the enclosure wired off board.

So I don't know if you want to go that far in modifying the layout just to have some options included that probably just a few of the pcb buyers would use.

After modding the Mistress for TZF I just know that I want a TZF ADA. The stereo out isn't included in my TZF Mistress but I assume that it would be cool to have "in-air-mixing".  So I want it for my ADA.   

BTW, did you yet decide on the enclosure? Maybe a 1590D (or DD) would be nice.

Regards,

Markus

[StephenGiles]

For what it's worth, when the sweep on the ADA gets right up there, the volume drops considerably so it's fine in your music room at home, but in a band stuation??

[RaceDriver205]

Re the TZF option: the pads could be easily integrated

Do it, I swear to god! A Through-zero ADA Flanger would finally quench the desire for 'jet engine' that people have. We would have the ultimate flanger, which is why I entered this game in the first place. It would be nice to make that my final effect.
Seriously, I can't stress enough how important making this ADA + TZF layout is. It would be a great achievement everyone!

[markusw]

For what it's worth, when the sweep on the ADA gets right up there, the volume drops considerably so it's fine in your music room at home, but in a band stuation??

Suppose that is primarily in "odd" mode (if I got it right in odd mode the phase of the delayed is inverted compared to the dry signal) because I didn't observe this phenomenon with my TZF Mistress which doesn't have a phase inverter. With the Hoax if the phase is inverted there is complete cancellation at TZF.

Do it, I swear to god!

I for sure will do in my unit but since the pcb Charlie wants to design is supposed to be a forum-pcb I believe it should also be a forum decision.

Once more mod: for TZF it probably would also be a good idea to have a "ultra-slow" switch for the LFO because the rate actually is multiplied by 2 if the fixed delay is engaged, at least with a symmetric TZF point. Please correct me if I'm wrong.


Markus

[StephenGiles]

You could have a VCA on the output which kicks in as the sweep approaches the TZF point to compensate for the volume drop - an opto perhaps, driven by appropriate circuitry.

[moosapotamus]

For what it's worth, when the sweep on the ADA gets right up there, the volume drops considerably so it's fine in your music room at home, but in a band stuation??

Like Markus said... I'm also assuming that this just happens in "odd" mode, yes/no?

...I want to compare rev3 and rev4 by doing Spice simulations.

Yeah, I guess that would be interesting. I'm actually still a little confused on the whole "version" question. The way I'm interpreting all the info that's flying around right now is that the one to build is Mike Irwin's SAD1024 adaptation as shown in Stephen's schematic. I don't mean to beat a dead horse on this question but, in my mind, he's still got a little kick left in him. So, am I on the same page as everyone here?

... Adding the pads for the stereo out option shouldn't be a problem.
... Re the TZF option: the pads could be easily integrated.
... Adding the additional delay pot for the fixed delay to the main pcb...

So I don't know if you want to go that far in modifying the layout just to have some options included that probably just a few of the pcb buyers would use.

I think it makes sense to include all those mod options (and any others that we might think of ). I don't think adding pads for this stuff will take up much more space on the board than several resistors. While we may not know exactly how the mods will be done, it seems we can at least determine where to insert some extra pads to allow for whatever "experiments" folks want to try. Then, at some later date, perhaps someone could design a "daughter board" that could be tied into the main (stock circuit) board to implement all the mods.

BTW, did you yet decide on the enclosure? Maybe a 1590D (or DD) would be nice.

Exactly what I was thinking... 1590DD is my first preference (7.38" x 4.70" x 1.3" deep, just a bit deeper than a 1590B).
The 1590D is 2.05" deep which is about twice as deep as a 1590B.
http://www.hammondmfg.com/dwg.htm

Another thing to consider is whether or not to have all the pots mounted to the board. Just look at all those traces that are needed on the rev.3 and rev.4 boards just to get the pots to line up in the desired order and mount to the upper section of the PCB. It increases the size of the PCB by maybe ~30%.
But, there are pros and cons...

PROS
I it eliminates a lot of off-board wiring and saves a lot of time.
Reduces the chances of making a wiring mistake.
Simplifies troubleshooting.

CONS
It eats up a lot of board space.
Could require a larger, deeper enclosure.
Takes up space that could be used to add off-board modifications (i.e. TZF).
Takes up even more space if the builder wants to orient the controls differently (i.e. on the side of the enclosure).

If the pads for wiring to the individual pots were simply grouped together on the PCB (i.e. 2 pads for the speed pot located right next to each other, 3 pads for the range pot located right next to each other, etc...), the wiring would at least be less confusing than if the individual pads were scattered around the board. I'm not totally opposed to keeping the pots mounted to the PCB. Just weighing the options.

Any other thoughts?

Thanks
~ Charlie

[StephenGiles]

The only snag with pots on the pcb is that it restricts the type of pot used. Personally I would rack mount this beast, then there would be plenty of space for expansion - then perhaps have a footswitch for on/off and other switching.

[markusw]

You could have a VCA on the output which kicks in as the sweep approaches the TZF point to compensate for the volume drop - an opto perhaps, driven by appropriate circuitry.

One more module to add as an option 

The way I'm interpreting all the info that's flying around right now is that the one to build is Mike Irwin's SAD1024 adaptation as shown in Stephen's schematic.

This is also my interpretation. Should be rev4 + the MI mods if I got it right.

I think it makes sense to include all those mod options (and any others that we might think of ). I don't think adding pads for this stuff will take up much more space on the board than several resistors. While we may not know exactly how the mods will be done, it seems we can at least determine where to insert some extra pads to allow for whatever "experiments" folks want to try. Then, at some later date, perhaps someone could design a "daughter board" that could be tied into the main (stock circuit) board to implement all the mods.

I think we just have to figure out whether the stereo out option needs an additional filtering stage and whether this stage should be incorpotated into the main pcb.

Exactly what I was thinking... 1590DD is my first preference (7.38" x 4.70" x 1.3" deep, just a bit deeper than a 1590B).
The 1590D is 2.05" deep which is about twice as deep as a 1590B.

If we can fit the main board into a DD then a DD could be used for the stock ADA and a D for the modded two-pcb version.

Re pots: I still would love to have them pcb mountd or at least to have the pads aligned for making the pots optionally pcb mounted.

The only snag with pots on the pcb is that it restricts the type of pot used. Personally I would rack mount this beast, then there would be plenty of space for expansion - then perhaps have a footswitch for on/off and other switching.

I believe if we go for e.g. 16 mm alpha pots it would be a good choice because they are easily available. They could be pcb mounted (by using three pieces of solid wire; works pretty nice IMHO) or alternatively off-boardwith using stranded wire . Also the 16 mm pots could be adjusted for height when pcb-mounted using solid wire. So there could even be some components placed below the pots.

For me the one Q is: should the pcb be designed around the options (e.g. having the second delay line's pot as well as a possible filtering stage for stereo out on the main pcb) so that it can also used be for the stock schem. This way the mods could probably be more easily incorporated. Or should it be designed around the stock schem which would cause more off-board wiring in case of doing the mods. Probably, the decision will depend on how many of the buyers want to add the mods.

Markus

[StephenGiles]

I suppose I always feel that a rack on top of an amp looks more flash. Still that's just me. If you can get it in a small box, all well and good.

[markusw]

I suppose I always feel that a rack on top of an amp looks more flash. Still that's just me. If you can get it in a small box, all well and good.

Suppose it's not going to be a really small box more like a BOX. 
Rack would also be cool but I think a 1590D/DD should be possible.