ADA Flanger MN3007 retrofit PCB

IggY · Post by **IggY** » 15 Jan 2009, 08:23

PCBs for the new ADA Flanger MN3007 project for sale at https://www.diystompboxes.com/smfforum/ ... ic=73483.0
(to access the link, you will have to register in the DIY-stompboxforum).

analogguru · Post by **analogguru** » 15 Jan 2009, 08:36

cool.....
after registering and login you will be able to read this:

moosapotamus wrote:OK, it's about time to get this group buy of PCBs for the new MN3007 version of the A/DA Flanger clone rolling.

The documentation page is still in the works, but soon enough it will all be here...
http://moosapotamus.net/IDEAS/ADAflange ... N3007.html
Cost with shipping included for each PCB will be...

In the continental USA:

$27 each if buying up to nine (9) PCBs
$23 each if buying ten (10) or more PCBs.
Anywhere else in the world:

$31 each if buying up to nine (9) PCBs
$27 each if buying ten (10) or more PCBs.

All payments must be made in US Dollars in advance via PayPal to my PayPal ID...
charlie AT moosapotamus DOT net.

In order to help me keep things straight, please type the following in the PayPal subject line...
Flanger PCB [your forum name] [number of PCB's you are paying for].
For example... Flanger PCB moosapotamus 2

Please do not forget to include your name and shipping address.

I will place the group order for the PCBs once the count hits ~20+.
Once all payments are received, the order will take ~10 days for production + 2 days shipping to me.

I will send the boards out to everyone via USPS as soon as I receive them.

This is for ExpressPCB's production service (2-sided, plated thru holes, with silkscreen and solder mask included).

Thanks
~ Charlie

bajaman · Post by **bajaman** » 03 Mar 2009, 21:38

The following is my first post over at the "other forum" in more than 2 years

I purchased one of the moosapotamus (Charlie) MN3007 retrofit boards because I had some free money in my Paypal account

I purchased a board from Moosapotamus - very nice board too! However I was less than overjoyed when i plugged my guitar in and played it (after setting it up with a frequency counter, a scope and the correct ADA calibration procedures). So - I set to work reading, downloading ALL the ADA schematics I could find and comparing them to the Boss BF2 etc.
Here is what I discovered (the board I am using is the one designed to accomodate the Panasonic MN3007 BBD chip - modified by oldschoolanalog).
The board has an additional 78L05 regulator fitted (silkscreen is 180 degrees wrong for this IC!!!!) to power the CMOS and BBD chips - why!!
I fitted a 47 ohm resistor in it's place (input to output pin on the board) to obtain the much higher headroom available ( the MN3007 is designed to work from + 15v dc anyway!!).
I fitted an additional 22k resistor (track break required) in series with the 10n capacitor and the inverting input of the gain stage immediately following the BBD outputs.
This allows a much deeper flanging effect to be heard (it could be a 20k preset with a 10k in series fitted externally if desired ).
I noticed more than one person on another 38 page thread on this site, complaining about the wobbly unatural and unusable high speed and partial solutions to this problem.
Okay - the original ADA flanger used a SAD1024 and then a MN3010 when the SAD became scarce. Both of these chips can give a 1024 stage delay, HOWEVER, they are both used as 512 stage delays in the ADA Flanger - take a closer look at the schematics - that's right, the inputs and outputs are paralleled in BOTH cases.( the MN3010 is two independent 512 stage delay lines)
The oldschoolanalog suggestion to use the MN3007, which is a single 1024 stage delay line has merit - it is still relatively easy to source and cheap (compared to the MN3005 and MN3010 etc.) BUT because we are now using double the delay line of the ADA Flanger we need to double the clocking speed to get the same results.(perhaps two MN3007 chips stacked would get closer to the MN3010 performance??!!).
The correct clocking speed should now be 69.6KHz to 2600KHz (not 34.8KHz to 1300KHz as in the ADA calibration specsheet)- don't worry the additional current buffers (CD4049) fitted, easily allow the MN3007 to be clocked at this higher speed.
I had to increase the 82k in series with the clock range trim pot to 150k to set the higher clocking speeds.(R65)
In conclusion - after these modifications the TRUE sound of the ADA Flanger was heard at last. I am genuinely surprised that no one has seemed to notice that the MN3007 was double the delay line length required for this circuit though.
cheers
bajaman

I must say I like this Flanger very much after the modifications and the board fits in a NSC1790 case easily.
I will post some pictures soon.
cheers
bajaman

IggY · Post by **IggY** » 04 Mar 2009, 07:00

nice to see that this thread was so fruitful!

for others still interested in the ADA Flanger matter,
that new part of the story is being continued in the following thread:
https://www.diystompboxes.com/smfforum/ ... #msg607475

bajaman · Post by **bajaman** » 04 Mar 2009, 09:57

....................and here

Hi again guys
I have been hangin' out on 'the other forum' for the last couple of years so please excuse me if I have missed anything.
one of "the other forum's" members posted a link to moosapotamus and old schoolanalog's retrofit MN3007 boards for sale.
I purchased one of these boards from moosapotamus - very nice board at a good price too - and decided to build it.
When I had finished it I was a little disappointed in the "ugly sounds" it was producing,. This led me to further research the original ADA Flanger and it's versions.
in the process I read a 38 page thread on the ADA and TZF right here on Diystompboxes. Maybe I missed something but i could not see any reference to doubling the clock speed when using double the delay line length. Maybe I missed it BUT, running the clock at half the neccessary speed is the major reason for the "ugly sounds" encountered by many who have built this latest clone version. Honestly, once you double the clock speed ALL the speed and range settings are pleasant and extremely usable.
Another problem encountered during this build was the threshold circuit operation, although this is the first time I have mentioned this. I have tried 2SK117, 2N3819 and the old favourite here - the J201 AND none of them work properly with the ADA threshold circuit. I suspect a lot of builders simply leave the fet out and disregard the threshold control function. The problem is without the fet in position the 1 Meg resistor from drain to source is - well 1 Meg in resitance. Consequently the signal level from the BBD and its following inverting gain stage is very large. With the jfet in the circuit this 1 Meg resistor is paralleled by the drain source resistance of the fet and is typically a lot lower than the 1Meg resistance - it is closer to 120 ohms. This provides a large attenuation of the delayed signal unless the threshold level control voltage acts to turn the fet off.
Even with large line level signals processed by the threshold circuit the fet resistance is still very low - typically in the 3.5K ohms region with a 2N3819 n channel jfet. I went as far as replacing the threshold control pot with a 100k linear pot to get the threshold control to actually work at guitar input levels, but this is something i am still working on, and I will let you all know of my findings.
Naturally, there is a great degree of interaction between the threshold level setting and the gain of the inverting stage following the BBD chip - more later
In the meantime try the mods I suggested in my last post ( it does not matter which side of the 10n capacitor that the 22k resistor is placed ) and double that clock speed for the MN3007 as well as running it from a dropper resistor directly from the 7815 regulator ( toss the 78L05 - it is not needed!)
With regard to using the MN3207 - you will not only need the lower voltage supply but also a completely different layout because it works from a negative NOT a positive ground as the MN3007 runs from
Have fun - more soon!
cheers
bajaman

bajaman · Post by **bajaman** » 04 Mar 2009, 10:01

follow up regarding the threshold circuit, fets etc.
I just spent the last couple of hours playing with the threshold circuit whilst monitoring the waveforms on the scope.
I retained the 100k linear threshold pot (I just could not get the range from a 10k pot).
With the threshold control fully clockwise it is efectively out of the circuit and consequently the fet is turned hard off.
With this setting and a socket for the fet on the board, I tried a range of n channel jfets that I had stock of. None of the different fets tried had any effect on this setting ( I was comparing to no fet at all in the socket ). However, when I turned the threshold control fully counter clockwise the differences were astounding (well interesting perhaps).
First up the J201 - hardly any difference at all from fully clockwise - not suitable
Next The 2SK117 - slight attenuaton - again not suitable
Then the MPF102 - hardly any attenuation - not suitable
Then the 2SK30 - again not suitable
Then the 2N5457 - very slight attenuation - not suitable
Then the 2N5459 - aha approximately 30% attenuation - looks promising......
BUT when I installed the 2N3819 I got maximum 50% attenuation - ideal - I tried a few more and they all worked fine.
I must get the correct fet LS4393 (or 2N4393) and try it, but for now the 2N3819 works as it should and almost completely attenuates the BBD output leaving just the dry signal.
One interesting discovery along the way - the best flanging effect occurs when the dry and delayed signals are the same intensity. After adding the 22k resistor as I suggested in my earlier post it is neccessary to adjust the trim pot on the output of the BBD (shown as simply TR on moosapotamus schematic) to obtain the same level of delayed signal as the dry signal - this is easy to see on the scope - just set the range control fully counterclockwise and use the manual control to sweep up and down - you will see the delayed signal collapse as you turn the threshold control fully counterclockwise - take a note of the dry signal level. Now turn the threshold control to full clockwise and adjust the trim pot TR until the signal level is now twice the dry level - you may have to sweep the manual control to give a clear picture on the scope.
Try these suggestions and you WILL get a whole range of very usable and satisfying sounds from this Flanger design - On the other hand tweak away in the darkness and you may get some meaningful sounds from within the chaos. Seriously - unless you have a scope and a good digital mulimeter with a frequency counter function on it you are never going to hear the GREAT sound this baby is capable of giving you.
Cheers
bajaman

gena_p1 · Post by **gena_p1** » 27 May 2010, 09:37

Did anybody tried J177 in this threshold circuit?

JimiMan · Post by **JimiMan** » 03 Jun 2010, 23:19

Hey if anyone's interested, Im selling the board for the sad1024 version, plus the sad chip itself. I can do $60 for both...

sinner · Post by **sinner** » 04 Jun 2010, 08:46

gena_p1 wrote:Did anybody tried J177 in this threshold circuit?

I'm building that right now, I have two boards one is for me the other one for an friend of mine. I'll build one like that and report back. It can take several weeks, as I'm involved in to many projects at ones