A/DA Flanger does TZF?

[oldschoolanalog]

I settled on 33uf (C24) and C250k (P5). I found C500k a bit too slow for my taste. Also the response of the 500k got a bit too "bunched up" (too sensitive) at the fast (cw) part of the rotation.
Play around until your ears are happy  .

[powerplayj]

I settled on 33uf (C24) and C250k (P5). I found C500k a bit too slow for my taste. Also the response of the 500k got a bit too "bunched up" (too sensitive) at the fast (cw) part of the rotation.
Play around until your ears are happy  .

OSA,

Yeah, I remember you saying that earlier and my experience was identical.  I might try your 250C pot suggestion or just lower the speed range via a resistor.  .....also thought of putting a resistor in front and replacing the 500C with an even smaller value assuming I can tie down what my usable speed range (resistances) will be.

All,

Anyone have trouble tuning this due to 60Hz interference?  My meter only picks up 60Hz (I need to verify the range)

A friend of mine who also built this says he gets "duty" interference when using a signal generator and scope to tune.  I think he also tried using the 4049 output as a test point like OSA suggested but I don't think that worked either.  Ted, if you are watching maybe you can comment about how you set up your tuning with the generator and scope.

I think we can probably get in the ball park tuning by ear but I really need to get some knobs or else index the pot shafts because it gets complicated remembering where I have them all set and they seem to have quite an effect on each other.  Having the original ADA manual helps immensely though ( the chorus effect was stunning!).

[StephenGiles]

There is a way of changing the pot law using one or two transistors, I forget how, but when I get home from Argentina I'll post the circuit which is part of the Dual Gate/panner from Home & Studio Recording in 1988. It basically allows the use of the full turn of the pot where the control would otherwise be within 1/10 of the turn

[oldschoolanalog]

http://www.interq.or.jp/japan/se-inoue/e_ckt16.htm

A good quickie explanation.

[StephenGiles]

There is a way of changing the pot law using one or two transistors, I forget how, but when I get home from Argentina I'll post the circuit which is part of the Dual Gate/panner from Home & Studio Recording in 1988. It basically allows the use of the full turn of the pot where the control would otherwise be within 1/10 of the turn

I think this is the circuit, I'm on a duff PC in an internet place in Lavalle, B Aires.

http://img.photobucket.com/albums/v517/uncle_boko/potlaw.jpg

[powerplayj]

[/quote]
A friend of mine who also built this says he gets "duty" interference when using a signal generator and scope to tune. 
[/quote]

OK, we got together and tuned.  We used pin 10 of IC 6 for the min / max frequencies.  The min would only go as high as ~25 Hz which I like anyway.  For the threshold and speed oscillation tuning we used pin 2 of IC 2.  It sounds quite incredible now as I am noting some knob positions for various songs I'm trying to emulate the flange......."Unchained", "Run Like Hell", etc....  by the way, if you are a Rush fan, you will be in heaven!!!  I'm still debating placement but right now I like it at the end of my chain rather than in the loop.  Time to work on the enclosure.... (I hate this!!!  You get no 2nd chances at drilling!!!)  Thanks to Charlie, Stephen, OSA and all the others who have helped.....
 

[oldschoolanalog]

Way to go, powerplayj !
It's great to hear when when a build is a success...
 
BTW, did you notice any "lag" at the bottom of the sweep that was mentioned earlier?

osa

[StephenGiles]

How many working units are there now¿  Or is everyone still buggering around with mods ¿

[Joe Kramer]

Hey OSA and All,

Now it's my turn to post an apology.  In case anyone was paying attention, I said the Ross flanger outputs a sine wave.  Turns out that's only partly true.  It's a sine wave when the speed control is cranked up all the way, due to a hefty cap across the LFO output.  But at slower speeds, it's a rounded triangle with an odd glitch on the positive swing.  I made this mistake for two reasons: one, I scoped the waveform at fast speed only (to get a reasonable display on my lousy scope); and two, a slight difference in the Schmitt Trigger part of the circuit threw me into thinking it was substantially different from my fave LFO in the CE-2 here:

http://home.hetnet.nl/~chrisdus/download/ce2.gif

The difference in the above circuit is that the ground/reference voltage goes to the noninv input and the "feedback" is built around the inv input.  In the A/DA and Ross LFO, the ground/reference voltage feeds inv input with "feedback" around the noniv input, plus there's that .01 cap from output to inv input of the Schmitt trigger.  From what I can gather looking on the scope, that extra cap turns the Schmitt's squarewave into more of a trapezoidal wave.

Sorry to all for any confusion I may have caused!   

Regards,
Joe

[caress]

i just got a board and one of those rad sloped enclosures from joelap!  can't wait to wire this monster up...

one question though:  as there is quite a bit of reading on here, is there a list of mods that people have been doing?  i have the list that moosapotamus shared on his build notes, but i'm wondering if there are any others that are unique...

[gitaar0]

How many working units are there now¿  Or is everyone still buggering around with mods ¿

I would like to report another finnished build.

I used the pcb from the firts batch from Charlie.

It is working but I still have to calibrate the unit. Haven't had the time doing that properly. let alone play with it......

Thanks to Charlie and the rest.

Marc

[powerplayj]

Way to go, powerplayj !
It's great to hear when when a build is a success...
 
BTW, did you notice any "lag" at the bottom of the sweep that was mentioned earlier?

osa

I haven't put it through the paces to really pay much attention if lag exists.  I'm so ecstatic about the way it sounds and how versatile it is, that I have just been trying out all the potential sounds it can make.  I still want to play with the LFO caps.  Was there any particular setting where the lag was most apparent? 

Sorry to not answer your question and then pose one myself but what affect does the cap value have on the speed? 

[oldschoolanalog]

 
... what affect does the cap value have on the speed? 

In this thread. Pg 9/Reply178; Pg 10/Reply188. Thanks again markus, for those nice sims!

http://www.interq.or.jp/japan/se-inoue/e_ckt16.htm
A good quickie explanation.

Hey Joe, as somebody mentioned earlier; it's all good  . Test equipment sure acts funny sometimes...

[powerplayj]

BTW, did you notice any "lag" at the bottom of the sweep that was mentioned earlier?

osa

I can't tell if its lag or my inability to perceive the difference in sounds at lower frequencies....mine goes to ~ 25-28Hz. 

Thanks for turning me on to my favorite build yet!!!  I never was a flange guy until now!   I now realize flange/chorus are in many songs where I never gave it much thought....... for instance I heard Loverboy's "When It's Over" and "Turn Me Loose" (I know, a blast from the 80's past...there's a Paul Dean fan among us somewhere I know!)

[StephenGiles]

There is a way of changing the pot law using one or two transistors, I forget how, but when I get home from Argentina I'll post the circuit which is part of the Dual Gate/panner from Home & Studio Recording in 1988. It basically allows the use of the full turn of the pot where the control would otherwise be within 1/10 of the turn

I think this is the circuit, I'm on a duff PC in an internet place in Lavalle, B Aires.

http://img.photobucket.com/albums/v517/uncle_boko/potlaw.jpg

No, forget this because it turns a log pot into a "super log" with 2% of max resistance at mid position!

[TR in NC]

Well, this is my first post on DIY.  My buddy powerplayj turned me on to the ADA Flanger clone and I’m glad he did!  I owned one in the 80’s and thought, could this sound as good as an original? And the answer is yes! This thing sounds fantastic!

Here’s some info on how I went through the setup procedure.

1.   Of course verify power (all IC’s etc.).
2.   Clock frequency adjustment.  I don’t want to spell out the bench test procedure so here’s my easy calibration.  Measure frequency with a scope at IC6 (CD4047) Pin 10 (pin 11 will also work).  Adjust Threshold, Manual, Range, Speed and Enhance pots fully CCW.  Adjust TR5 fully CW, Adjust Manual pot fully CW, Adjust TR4 to 1.3MHz.  Adjust Manual pot fully CCW and verify min frequency (mine was around 21.7KHz).  Bench spec states min 34.8KHz, max 1.3MHz (I could not adjust TR4 and TR5 to get both setpoints).  You can adjust the low end up but this also raises the high end of the sweep range.  I chose to keep the low end at 21.7KHz (you can compromise in either direction).
3.   BBD Bias and Regeneration.  This is where I didn’t have any luck with the bench test procedure.  When I thought I had everything setup I hooked it to my amp and nothing.  So here’s my easy setup procedure.  With the output connected to your amp (keep amp volume VERY low), Adjust Threshold, Manual, Range, Speed and Enhance pots fully CW.  Set TR1 fully CW and TR2 fully CCW.  Adjust TR1 CCW just until you hear the full sweep next; adjust TR2 until the sweep is almost fully attenuated.  Adjusting the Enhance pot will fully attenuate the sweep.  If you don’t want to hear the sweep at all with the Enhance pot fully CW then just adjust TR2 until the sweep is fully attenuated (I chose to hear the sweep so I know where the attenuation threshold is when setting the Enhance pot).

I kept both TR3 and TR6 at 50%, didn't really see much change with either of them.

That’s it! this has worked great for both powerplayj and myself.

Also, I did not see anything on the scope or hear anything abnormal with the low end of the sweep.

I do have one question on the Harmonics switch…which positions on the schematic are even and odd?

I hope this info is of some use?  It’s been a lot of fun building it and even more playing it!

[moosapotamus]

Nice report, TR. Thanks and welcome.

I do have one question on the Harmonics switch…which positions on the schematic are even and odd?

Odd/even is shown on the scheme... Even is with the switch making the connection to Vb, odd is with the connection to Vb broken.

~ Charlie

[powerplayj]

Well, this is my first post on DIY.  My buddy powerplayj turned me on to the ADA Flanger clone and I’m glad he did!  I owned one in the 80’s and thought, could this sound as good as an original? And the answer is yes! This thing sounds fantastic!

Here’s some info on how I went through the setup procedure.

1.   Of course verify power (all IC’s etc.).
2.   Clock frequency adjustment.  I don’t want to spell out the bench test procedure so here’s my easy calibration.  Measure frequency with a scope at IC6 (CD4047) Pin 10 (pin 11 will also work).  Adjust Threshold, Manual, Range, Speed and Enhance pots fully CCW.  Adjust TR5 fully CW, Adjust Manual pot fully CW, Adjust TR4 to 1.3MHz.  Adjust Manual pot fully CCW and verify min frequency (mine was around 21.7KHz).  Bench spec states min 34.8KHz, max 1.3MHz (I could not adjust TR4 and TR5 to get both setpoints).  You can adjust the low end up but this also raises the high end of the sweep range.  I chose to keep the low end at 21.7KHz (you can compromise in either direction).
3.   BBD Bias and Regeneration.  This is where I didn’t have any luck with the bench test procedure.  When I thought I had everything setup I hooked it to my amp and nothing.  So here’s my easy setup procedure.  With the output connected to your amp (keep amp volume VERY low), Adjust Threshold, Manual, Range, Speed and Enhance pots fully CW.  Set TR1 fully CW and TR2 fully CCW.  Adjust TR1 CCW just until you hear the full sweep next; adjust TR2 until the sweep is almost fully attenuated.  Adjusting the Enhance pot will fully attenuate the sweep.  If you don’t want to hear the sweep at all with the Enhance pot fully CW then just adjust TR2 until the sweep is fully attenuated (I chose to hear the sweep so I know where the attenuation threshold is when setting the Enhance pot).

I kept both TR3 and TR6 at 50%, didn't really see much change with either of them.

That’s it! this has worked great for both powerplayj and myself.

Also, I did not see anything on the scope or hear anything abnormal with the low end of the sweep.

I do have one question on the Harmonics switch…which positions on the schematic are even and odd?

I hope this info is of some use?  It’s been a lot of fun building it and even more playing it!

Thanks Ted!  First post and you're shelling out a tuning guide for the A/DA?  Where were you to help with my vibe?  BTW...I found trimmer 3 tuned clockwise attenuates the upper frequencies of the range such that you don't get those high freq acoustic sounds that seem to be above audible detection of the sweep.  Move your switch to "odd", set the range at 1/2 to 3/4 full and manual at 1/2 or so and you can here this a little better...IMO

[TR in NC]

Thanks guys, I may scope the board out some more just to get a better idea on how things look.  Powerplayj, I'll try to find out what TR3 is actually doing (may be acting as a high freq rolloff?).

Ted

[TR in NC]

A follow-up to my calibration post.  I had some time today to look at some datasheets and learn a little more about the circuit.  I was able to set TR6 to balance the 2 outputs from the delay chip (sad1024) I did this by looking at the output of the trim pot (r17 or pad G) and set TR6 to get the lowest Peak to Peak signal (null).  I also found that adjusting TR2 a little highter (a little more attenuation on the sweep) I was able to get a better clean signal with the Enhance pot fully CCW which made for a better clean signal (with the Enhance pot fully CCW you can achieve an awesome clean chorus!) which this circuit does great!  I don't know if I want to mess with it anymore....this thing sounds...well...GREAT!

Ted