CAN I USE MN3207 INSTEAD OF MN3007 TO BUILD CE-2 CHORUS

[litstalov]

Hello everyone!
I'm new here and this is my first post... here it goes...

I'm trying to build a Boss CE-2 Chorus clone with the tonepad.com layout.
I bought a PCB from tonepad (nice boards they make!), and all components... well, all but the damn' MN3007 IC.
I cannot find it in any local store, and online I can find it only in smallbear... I can also find NTE1641 (which I read is a pin-for-pin substitute for MN3007). My problem is that I live in Portugal (yes, that's in europe, next to Spain), and ordering any of this parts from the USA is very expensive... for the money I have to pay for these chips, I can buy a used original CE-2 here in Portugal. So, unless I can find these little devils here in Portugal or online shipping from europe, it's absolutely out of the question.

So, now I have a populated board with all other components, and an empty socket wating for a BBD chip... and already wired and fitted in the enclosure... frustrating!

And here's my question: here in Portugal I can buy the MN3207. Will it solve my problem? I already read about not being pin-for-pin similar, and most important, different in terms of negative/positive input voltage. So, is there any way I can use MN3207 with the tonepad layout? What kind of changes do I have to make?

Any help? I will include you in my last will and testament!!!
Thanks.

[artifus]

don't know if this is a good price or not but these guys are in ireland which is at least in the eu: http://www.donberg.ie/descript/m/mn_3007.htm

[GGBB]

Banzai has them much cheaper:

http://www.banzaimusic.com/MN3007.html

[Scruffie]

I believe Govtlacky posted a thread doing just that.

You can also look at the Madbean pork barrel schematic, that can switch between the 3007 & 3207 so it'll show you how to change the schematic.

[maartendh]

I have done this too, substituting a 3207 for a 3007 in an chorus; dont recall whether it was a Boss CE-2 type, but then, these chorusses are all pretty much the same. The adaptation was easy to make. IIRC, just changing the pins for supply and ground.
Maarten

[Govmnt_Lacky]

I believe Govtlacky posted a thread doing just that.

You can also look at the Madbean pork barrel schematic, that can switch between the 3007 & 3207 so it'll show you how to change the schematic.

I ended up building a CE-3 and modding THAT to the specs of a CE-2. It is only a transistor and resistor change and its all good! 

[litstalov]

Thanks. Until now this is the cheapest solution to buy mn3007.

eur8,57 + eur8 for shipping costs = eur16,57 (about 21,90 USD) still a bit out of what I wanted...

Banzai has them much cheaper:

http://www.banzaimusic.com/MN3007.html

[juansolo]

Doctor Tweek in the UK has them at a very good price, not sure if they ship overseas, but worth a try.

I've bought loads from them, all worked with no problems.

http://www.doctortweek.co.uk/shop/article_286/MN3007-_-MN3101-Package.htm

[aswang05]

  It seems that MN3007 is like an extinct dinosaur here in my country, what I got is an MN3207. I hope that i won't fry it 'cause it's the last one from the store.

[Mark Hammer]

If you know anywhere that stocks ECG/NTE replacements, the ECG/NTE 1641 is a replacement for the MN3007.

[aswang05]

I did ask if they have the NTE but it was sold out. well, since i am very desperate to have a chorus so i just bought the MN3207. I hope adjusting the trimmer will do the trick droping down the supply to 5v

[Mark Hammer]

The 3207 does not HAVE to operate on 5v, and will work with 9v.  Manufacturers tend to use it with 5v because doing so allows them to provide a stable bias.  If they use a trimpot to bias the BBD, and the battery starts to drop from 9.4v (fresh out of the package), to 9, to 8.5, to 8, etc., the bias will become increasingly inaccurate and the delay sound start to deteriorate.  If they drop the 9v down to 5v and take the bias from a stable 5v, then by the time the battery has dropped below the minimum voltage the regulator needs (7vdc) to provide a stable 5v, the pedal is not going to work anyway.

The 32xx series seems to have been developed to solve a problem produced by powering such pedals with batteries.  If one's intent is to power it with an external supply that will not die out, then the goal of providing a stable bias voltage from 5v becomes unimportant, and one is free to operate the BBD from 9v.  It may even have better sound that way.

[Fender3D]

I hope adjusting the trimmer will do the trick droping down the supply to 5v

Watch out:
MN32xx has power supply reversed respect MN30xx...

If you don't change pins connections, you'll fry it.

With MN 32xx, you MUST connect pin 1 @ GND and pin 5 @ +V
then, you must connect outputs resistors (pin 7 & to GND instead +V
if you don't use MN31xx, voltage @ pin 4 should be 14/15 (+V)

[aswang05]

If that's the case then I will just cut some traces then rewire it. But I check the datasheet, it seems to be identical to the orientation of the MN3007. Please correct me if I'm wrong

[aswang05]

Fender3D is right!!! thnx a lot bro!!! ! more question, If MN3101 is not available, can I use MN3102?

[Govmnt_Lacky]

Fender3D is right!!! thnx a lot bro!!! ! more question, If MN3101 is not available, can I use MN3102?

MN3101 can be used with the MN3007

MN3102 can be used with the MN3207

You can't mix and match 

[aswang05]

ahmmm, ok....my bad

[wickedme]

Hey Litstalov if you live near Leiria and you haven't found a mn3007 yet I might be able to help you. As long as you are any good at de-soldering... I have an old Trace Elliot amp I have scavenged for parts and it has both an MN3007 and an MN3101. You can have'em for free.

[Valentinych]

litstalov, perhaps this will help you:
http://www.diystompboxes.com/smfforum/index.php?topic=101993.msg903153#msg903153
Reviews, sound is not worse than that of the CE-2.

[Baran Ismen]

Beating a dead horse here for the very same inquiry. Theres a daugtherboard for 3007 to 3207 but im unsure about the voltages. Also their datasheets state that they both have same pinout, what about that?