A/DA Flanger retrofit with MN3007

[WLTerry]

That's a nice job guys! Does the new circuit still needs to be fed with 15V as required in the SAD1024 version? Or now it's OK to feed the circuit with 9V or 12V? And just we should tweak trims T4 and T5 to double the clock frequency? And why is that? because SAD has 512 stages and MN3007 has 1024 stages?

Thanks
Will

[oldschoolanalog]

That's a nice job guys! Does the new circuit still needs to be fed with 15V as required in the SAD1024 version? Or now it's OK to feed the circuit with 9V or 12V? And just we should tweak trims T4 and T5 to double the clock frequency? And why is that? because SAD has 512 stages and MN3007 has 1024 stages?
Thanks
Will

Thanks Will! Yes, the intention is to keep the supply 15V. Haven't tried it at 9V or 12V. The idea was/is to do this change w/as little modification to the existing circuit as possible. And... Yes, doubling the number of BBD stages requires doubling the clock f to maintain the same delay range.
Dave

[snap]

see subject line (3207).

btw, list of literature useful for this thread:

http://www.diystompboxes.com/smfforum/index.php?topic=49929.0
http://www.diystompboxes.com/smfforum/index.php?topic=51703

http://moosapotamus.net/IDEAS/ADAflanger/ADAflanger.html

http://www.diystompboxes.com/smfforum/index.php?topic=51692.0
http://www.diystompboxes.com/smfforum/index.php?topic=52219
http://www.diystompboxes.com/smfforum/index.php?topic=53679.0
http://www.diystompboxes.com/smfforum/index.php?topic=54798.0
http://www.diystompboxes.com/smfforum/index.php?topic=56307.0
http://www.diystompboxes.com/smfforum/index.php?topic=60150.0
http://www.diystompboxes.com/smfforum/index.php?topic=64771.0
http://www.diystompboxes.com/smfforum/index.php?topic=70867.0

[oldschoolanalog]

see subject line (3207).

I see it "2".
 
Please elaborate.
Thanks.

[StephenGiles]

why not buffer with three inverters in parallel on each phase?
(immediately after the 4047?)

I can't lay my hands on the text from Mike, but I believe he abandoned "three inverters in parallel on each phase" for a good technical reason - possibly something to do with clock rise and fall times?

[oldschoolanalog]

why not buffer with three inverters in parallel on each phase?
(immediately after the 4047?)

I can't lay my hands on the text from Mike, but I believe he abandoned "three inverters in parallel on each phase" for a good technical reason - possibly something to do with clock rise and fall times?

In the Ultra Flanger Mr. Hollis uses the 3 inverters in parallel on each phase to clock the MN3007 to ~1MHz. Hmm... I would like to know the technical reason if anybody could help with this. Please.
Check it out:
http://www.geofex.com/PCB_layouts/Layouts/ultrafln.pdf
The reason it's not being done here:

The idea was/is to do this change w/as little modification to the existing circuit as possible.

It works just fine the way it is. "If it ain't broke; don't fix it."
Dave

[snap]

see subject line (3207).

I see it "2".
 
Please elaborate.
Thanks.

2 as in: MN3207 (BL3207 or V3207) low voltage versions,
for once the Panasonics 3007s are starting to vanish.

[oldschoolanalog]

2 as in: MN3207 (BL3207 or V3207) low voltage versions,
for once the Panasonics 3007s are starting to vanish.

Understood. Point taken.
However, as I previously stated :
  Re: A/DA Flanger Clone PCBs - LAST BATCH?
« Reply #39 on: November 10, 2008, 11:04:12 PM » 
Quote from: Nitefly182 on November 10, 2008, 07:19:00 PM
Which means we are focusing on the cool audio clones of the MN3207 and not actual MN3007s because the same thing will happen with them.
To which I replied:
Another thing that crossed my mind when starting this project was just that. However; I wanted to keep the unit working at 15V. The max supply V with the 3207 would have been 9V. Such a radical change would probably necessitate changing other parts of the circuit. Also, IMHO, the 300x series BBD's sound better than their 320x counterparts. There are loads of 3007's available for real cheap. If cost is any indication of quantity available, then there are most likely alot more of these out there than one can imagine. I recently purchased 10 pcs. MN3007 for ~$20US. Less $$ than the cost of a single SAD1024! From a US distributor (not HK). Upon testing they all worked perfectly. I don't think a short run of this PCB is going to have much of an effect on the availability of the MN3007. Heck, if you look at the projects at Tonepad alone, you will find 3 that use the 3007. This hasn't seemed to put a dent in their availability; and I'm willing to wager it won't for the forseeable future. However, after this anything I design in the future will use the newer Cool Audio chips. Just to practice what I preach, so to speak.
Dave

Note the last 2 sentences...

Once the 3007's vanish maybe somebody will do another redesign. 

 

[snap]

sorry, OSA for not having read through those for sale-threads completely
and therefor having missed that part  .
thanks for your explanation.

Stephen: maybe some unbuffered version of hex inverters sports fast enough slopes
to follow the 4047 directly, but I`m not aware of their "fan-outs".

[StephenGiles]

I'll keep looking for Mike's email, I used to print them out at that time.

[StephenGiles]

Found it saved to a Word document - I was looking for a text file!

Mike said:

" I would have liked to use the 4049 inverters set up as two groups of
three paralleled inverters - but the 4047 is not able to drive the
combined gate input capacitance very well... so the technique shown has
been used as a compromise to preserve good rise/fall times."

Hope that is of some help.

[oldschoolanalog]

Thanks Stephen! That helps a bunch. As always, your efforts are greatly appreciated.
Hey snap, it's all good. I believe there are at least 4 threads about this out there. Gets confusing for sure.
Dave

[moosapotamus]

Before I finish updating the PCB layout for the MN3007, here's a question...

What about including a spot for a 78L09 regulator on the power rail to the BBD, only? This would allow folks to experiment with some of the 3207 BBD chips that can only take a 9V supply, such as the BL3207 or the V3207. They seem to have the same footprint as the MN3007. What I'm not positive about is if the same associated components in OSA's 3007 retrofit circuit would be sufficient to get one of these other BBD chips working with, maybe, only a few value substitutions. Anyone have any thoughts about this? If using the MN3007, you could just install a jumper across the 78L09.

~ Charlie

[Zben3129]

If you are asking if a 3207 would work in place of a 3007 with use of a 9v regulator then the answer is no. 3207 chips use positive supply voltage while 3007s use negative supply voltage(maybe thats backwards), so all the Vdd Vgg etc would be incorrect in polarity.

If anyone disagrees then speak up because I am not 100% sure on this.

Zach

[flo]

Something I saved to textfile a while ago:

Swapping MN3007 for a MN3207

http://www.diystompboxes.com/smfforum/index.php?topic=56291.0
Some quotes from that thread:

"The functions of the pins are the same, but that does not mean that what voltages they are supposed to see are identical.  Personally, I have never understood all the things that needed to be changed, but I do know that it is not as simple as sticking a 3207 in the socket and simply flipping the GND and supply lines.  There is also the issue of the bias voltage."

"When running the bias supply to be able to go from ground to the full supply voltage one should be OK to set it correct for a 3207.
Other than that:
- Reverse the power supply pins. V+ (Vcc, Vbat or whatever) becomes ground and the ground becomes V+.
- Change the output resistor going from output to to V+ in the 3007 case and run it from output to ground in the 3207 case.
- If your supply voltage is higher than 9 volts use a 7809 to limit it to 9 volts far the BBD AND the BBD bias."

"For the clock driver the setup is similar. Make use of the datasheets on Mark Hammer's website (BBD Dementia, Panasonic Paranoia or whatever the name was but, and I'll always mention this: Thanks so much for that file Mark!)  for these chips and make a comparison between a chorus like the CE2 (GGG.com?) and any BBD loaded Ibanez chorus found online. The differences in connecting is what you're looking for and the above will become clear."

[Michael Allen]

I've replaced MN3007 with MN3207 and it requires a minimum of changes to external circuitry but there is rewiring necessary. The pinouts aren't the same and like was mentioned, one runs on (+) voltage and one on (-) voltage. Since you have to replace the BBD and Clock, you'll be changing ground/power connections in two parts on the circuit. It might be worth creating a separate PCB for it, since cutting traces and adding jumpers is real messy. It's only like two or three traces that need to be rerouted so shouldn't be hard to change them and pump out a new PCB. Then you can add the regulator as well.

http://www.diystompboxes.com/smfforum/index.php?topic=68806.0

[Michael Allen]

oops. got ahead of myself.

you're only replacing the BBD not the clock. That was in reference to previous circuits replacing the MN3007/MN3010 combo..

[theehman]

I've replaced MN3007 with MN3207 and it requires a minimum of changes to external circuitry but there is rewiring necessary. The pinouts aren't the same and like was mentioned, one runs on (+) voltage and one on (-) voltage. Since you have to replace the BBD and Clock, you'll be changing ground/power connections in two parts on the circuit. It might be worth creating a separate PCB for it, since cutting traces and adding jumpers is real messy. It's only like two or three traces that need to be rerouted so shouldn't be hard to change them and pump out a new PCB. Then you can add the regulator as well.

Why not just a few headers with jumpers?

[moosapotamus]

Why not just a few headers with jumpers?

Well, that's exactly what I was thinking. But it's starting to sound like a 3207 adaptation would require a bit more development before committing the option to a run of PCBs.

~ Charlie

[Zben3129]

Also it can only run 9v

Zach