Flintlock Flanger (A/DA Flanger) Debug

[StephenGiles]

Ah, I also never bothered with the threshold control so didn't have any potential problems associated with that!

You're missing out Stephen! It can be quite effective for some interesting envelope controlled flanging rather than simple noise control.

Possibly, but I installed the bounce circuit from the Eventide Instant Phaser/Flanger which is even more interesting!!

[Tony Forestiere]

I don't trust the power supply at all. I suggest you disconnect it completely from the 15v regulator and connect up two 9v batteries instead - see if the noise goes away.

Try it.

[Dasher]

I don't trust the power supply at all. I suggest you disconnect it completely from the 15v regulator and connect up two 9v batteries instead - see if the noise goes away.

Try it.

Thanks Tony. It's on my list of things to try/check when I get back to working on it. I've put the flanger aside for the time being to finish up another build that I've had sitting around for the past year.

[StephenGiles]

My vero build!       
                                     

[Dasher]

I'm coming back to this debug after some time off and was able to confirm a couple of things last night. I powered the 15V regulator with 2x9V batteries in series (instead of using a 9v power supply with the charge pump), but the noise was still there. I also confirmed with my multimeter that pop noise happens at each end of the LFO cycle (i.e. I get a loud pop when the sweep turns around at 2.6mHz and at 69kHz.)

Later on today I plan to verify that all of the electrolytics and diodes have a positive voltage across them, in the right direction. This should help me rule out bad caps and diodes.

[Dasher]

Success! I got it working. Thank you for everyone's assistance!

The problem was my "Auto" trimpot. The legs on the trimpots I used had to bent significantly in order to fit the PCB. I must have bent one of the legs too far, causing the pot to malfunction. I readjusted the legs and now the effect is happily flanging away with no noise.

[Scruffie]

Congratulations on a successful debug 

I never would have thought of that.

[alfafalfa]

Great Dasher, you got it working!  I am very curious how it sounds , could you post a clip?

[StephenGiles]

Fantastic - now for a mod to create TZF - Flanger Hoax come on down!!!!

[Dasher]

Great Dasher, you got it working!  I am very curious how it sounds , could you post a clip?

I'll try to get a quick video posted in a couple of days. I still want to play with the "Bias" and "Mix" trimpots to get the flanging signal as clean and prominent as possible.

[Dasher]

Here's a short video:

https://www.youtube.com/watch?v=PrJwyjirX_M

I apologize for the uninspired guitar loop/playing, but it will hopefully give you an idea of some of the sounds that can be had with this effect.

I've also noticed another potential problem over the past couple of days; I can hear a very faint whining/squealing that comes and goes when the "Manual" pot is set in the first 50% of its rotation (fully CCW to middle) and the flanger is moving through the lower frequencies of its sweep. I measured the frequency at the test point near pin 13 of the 4047 (clock frequency?) and the whining seems to occur throughout the 69kHz to 200kHz range, approximately. Actually, if I set both the "Manual" and "Range" pots fully CCW, I can hear the faint whining constantly. To anyone else who has built this effect, have you noticed this behaviour? As I've already said, the noise is very faint...but now that I know it's there I can't unhear it  .

I thought it may have something to do with the charge pump so I tried powering the effect with two 9V batteries in series. The whine stopped. I think that I may eventually remove the charge pump and use a 18V power supply instead.

[Aph]

Yes, that's heterodyning of the charge pump oscillator and the clock. I just removed the charge pump and powered the flanger from an adapter I modified for 20v out.

[alfafalfa]

Although the clip is very soft, you get a good impression of what it sounds like.
I think it sounds really good as far as I can tell.

[Aph]

Although the clip is very soft, you get a good impression of what it sounds like.
I think it sounds really good as far as I can tell.

Not for the faint of heart, but it is one of the most satisfying builds I've ever done. I highly recommend the project:
http://lectric-fx.com/product/flintlock-flanger/

I actually built two of them. One with a MN3007 and one I modified for a SAD1024! I took my time calibrating the units and they both sound excellent!
Both units are powered with a 20v power source and no charge pump in the circuit.

[Dasher]

Alfafalfa; sorry about the low volume. My effect building time is after my kids go to bed so I have to keep amp levels low. I'm glad that the clip still gives you an idea of what it sounds like though! I'm sure there are other, better clips on YouTube.

Aph; thank you for the confirmation about the heterodyning. I decided to permanently removed the charge pump and power the effect with an 18v wall wart. It's much better now. I think I can officially call this build finished.

I second Aph's comment about this being a satisfying build. It's a bit more expensive and time consuming to build than many other effects out there, but I feel like it's worthwhile in the end.

[12Bass]

I actually built two of them. One with a MN3007 and one I modified for a SAD1024! I took my time calibrating the units and they both sound excellent!

Please comment on the differences in sound between them.  I'm curious to know if the SAD1024 has better high frequency response and perhaps more noise or if the differences are not that noticeable.  I have an SAD1024 A/DA clone based upon the moosapotamus project. 

Also, in related news, A/DA recently posted on facebook:

A/DA Amplification is feeling nostalgic.
October 15 at 2:56 PM ·

We have started a short run of original ADA Flangers using the Reticon SAD1024 bucket brigade chip! We found a few of the rare parts and are using the original printed circuit board layout and component values to achieve the exact same product A/DA shipped in 1978. We are using the same "big box" aluminum sand cast enclosure. The original Flanger ran off 18V DC and using an obsolete 2.5mm center pin positive AC Adapter. The only change we have made is to use a 2.1mm center pin negative DC power jack, which is standard for today's pedal boards.

[Aph]

Please comment on the differences in sound between them.  I'm curious to know if the SAD1024 has better high frequency response and perhaps more noise or if the differences are not that noticeable.  I have an SAD1024 A/DA clone based upon the moosapotamus project. 

A/DA Amplification is feeling nostalgic.
October 15 at 2:56 PM ·

We have started a short run of original ADA Flangers using the Reticon SAD1024 bucket brigade chip! We found a few of the rare parts and are using the original printed circuit board layout and component values to achieve the exact same product A/DA shipped in 1978. We are using the same "big box" aluminum sand cast enclosure. The original Flanger ran off 18V DC and using an obsolete 2.5mm center pin positive AC Adapter. The only change we have made is to use a 2.1mm center pin negative DC power jack, which is standard for today's pedal boards.

My hearing isn't the greatest to judge high frequency response. But, I can tell that the 1024 build is ever so slightly more noisy. This is because of the lower clock frequency I'm sure. Of course, I had to change some clock components to lower the clock. I made a little sub-board for the 1024 so I could plug it directly into the BBD socket.
It's funny though... the 1024 build was quite a bit easier to calibrate! (I used the original calibration sheet from A/DA).
I would say the differences are so slight it's not worth thinking about.

Those reissue A/DA Flangers with the SAD1024 must cost a pretty penny.

[chemosis]

I built 2 adas a couple years ago with 2 flintlock pcbs which are great pcbs and get a random loud pop then the flanging becomes weak and very jittery/fluttery. this happens on average about every 3-5 minutes but only last about 3 sec. sometimes a little longer. the same weird pop then flutter happens on both flintlocks. cant find much on it. does anyone know where I can get correct voltages? does this sound like a ground loop issue?? I will post a audio file or video in the next week or so