MN3007 and MN3207 Differences???

[Govmnt_Lacky]

Differences between the MN3007 and MN3207 BBDs.

I know that the Positive and Negative voltage/ground inputs are reversed but, what are the other differences?


DISCUSS.......

[Mark Hammer]

The MN3207 will run off lower supply voltages.  Most importantly, it will run off 5v.  This means that a 9v supply, whether battery or adaptor, can be regulated down to 5V, and the bias voltage derived from that stable supply voltage.  You CAN obviously run an MN3007 off a 9v battery, but if the bias voltage is derived by dividing down that supply voltage with a trimpot, as the battery voltage starts to change, that bias voltage becomes progressively less valid, even though the circuit and chip itself could probably run just fine off 8vdc.

Clearly, this particular advantage really only starts to apply when the pedal is operated from a battery, but given how many BBD-based pedals ARE run from a battery at some point, whether in a music store, a basement, a studio, or a gig, it can truly be considered an improvement.

Note that this is not necessarily a change in the tonal quality, but rather a change in the circumstances under which optimal tonal quality can be maintained.

[Govmnt_Lacky]

The MN3207 will run off lower supply voltages.  Most importantly, it will run off 5v.  This means that a 9v supply, whether battery or adaptor, can be regulated down to 5V, and the bias voltage derived from that stable supply voltage.  You CAN obviously run an MN3007 off a 9v battery, but if the bias voltage is derived by dividing down that supply voltage with a trimpot, as the battery voltage starts to change, that bias voltage becomes progressively less valid, even though the circuit and chip itself could probably run just fine off 8vdc.

Clearly, this particular advantage really only starts to apply when the pedal is operated from a battery, but given how many BBD-based pedals ARE run from a battery at some point, whether in a music store, a basement, a studio, or a gig, it can truly be considered an improvement.

Note that this is not necessarily a change in the tonal quality, but rather a change in the circumstances under which optimal tonal quality can be maintained.

Thanks for the info Mark. If what you said is true and the 3207 is indeed a "better" alternative, then why does the DIY community have so few designs based on this chip? I have found the Guyatone FL3 and 1 or 2 others however, this pales in comparison to the number of effects/designs involving the 3007.
Is this because no one wants to design around the 3207? Does the 3007 offer something that the 3207 does not?

Enlighten me....

[Mark Hammer]

I don't think the MN3207 is better or worse.  I suspect many design around the MN3007 simply because there is a sense that if a pedal operates off a higher supply voltage then good things will come from that.

I have to confess that the conditions under which I listen to pedals likely do not afford whatever "golden ears" I might (or might not) have to strut their stuff, so I can neither confirm or pooh-pooh the notion that an MN3007 running at a higher supply voltage will provide a higher quality signal.

[Valentinych]

Mark, I think you are wrong.  
With your vast experience BBD, I'm sure you know that some parameters of the MN3207 objectively inferior to those of MN3007, for example, signal to noise ratio (3007-80 dB, 3207-73 dB) and some are much better, such as the maximum Clock frequency (3007 – 100 kHz, 3207 – 200 kHz). Compare these two products could only be comprehensively, taking into account all major parameters.  I'll try to do it by evaluating each parameter on a ten-point system. Of course, I don't believe its conclusions correction.  

№   Options                                                    MN3007                                      MN3207
                                                             Value                Rating                 Value              Rating
1   Signal Delay Time (min/max)     5,12-51,2 ms              6                2,56-51,2 ms           10
2   Total Harmonic Distortion                0,5%                    8                      0,4%                  10
3   Input Signal Swing (Vi)                 1,5 Vrms               10                  0,36 Vrms                 5
4   Clock Frequency (max)                   100 kHz                7                    200 kHz                10
5   Supply Voltage (max)                      -15 V                    8                     +10 V                    8
6   Supply Voltage (min)                      -10 V                     8                      +5 V                   10
7   Dynamic Range (S/N)                      80 dB                 10                      73 dB                    7
8   Average Rating                                                       ~8,1                                             ~8,6

It is understandable that impossible to tell which of BBD-circuits better or worse. Each has its own characteristics, and select each competency, and their electronic devices. But if to evaluate these chips for devices to handle sound, it is preferable to MN3007 still in most cases.


Best regards, Valentinych.

P.S. Russians say: “Don't you love cats? You just don't know how to cook!”  

[oldschoolanalog]

Either can easily be clocked in excess of 1.5MHz. Just use a 4047 & 4049 (or other similar clock arrangement). You won't get arrested/beaten/jailed (unless that's your thing; but not to digress...) for clocking with something other than the MN clock chips.
If anybody here can honestly say they can hear (NOT "see it on a 'scope" or whatever) the difference between 0.4% and 0.5% THD here's your chance to speak up (have the KY ready 'cause you're gonna' get reamed). We are talking one tenth of one percent here folks.
Even then, the 3007's superior headroom and S/N ratio more than offset that 0.1%. Ya' think?
In my experience, at 12 to 15 V the MN3007 really starts to strut it's stuff. At 9V and under there is really very little to no difference between the two.
I have spent many hours experimenting with various BBD pedal builds and retrofits. This is what I base my comments on.
I urge everybody to do some experimenting if they have the necessary BBD's on hand. Or buy some. MN3207 & MN3007 are still easily sourced and not very expensive.
Specs be damned. It's what is in the ears, not what's on paper that counts.
End diatribe.
Thank You and Have a Nice Day!

[Govmnt_Lacky]

Or buy some. MN3207 & MN3007 are still easily sourced and not very expensive.

[Mark Hammer]

OSA/DaveW made my point more effectively.

When atypical supply voltages are used (i.e., >9v) the MN3007 can exceed the performance of the MN3207.  The 3207 was engineered, as near as I can tell, to provide more stable performance at 9v and under battery-operated conditions (excluding things like dual 9v battery single-ended supplies like the Ibanez FL-301).

[deadastronaut]

very old thread i know, but....

i'm about to bread up a chorus...but i'm not understanding the differences with the mn3007/mn3207

pinout wise?...when looking at the data sheets they are the same pinouts?

mn3007/mn3207.

1  gnd
2  cp1
3  in
4  vcc
5 vdd
6 cp2
7 out1
8 out 2

however, when looking at say the zombie chorus mn3007 pin 1 has 9v+ going to it, though its labelled GND...

so which is actually gnd on the mn3007?.  vcc or vdd?.. i just dont want to blow my chips. 



i intend to try the mn3207 really
so what is the actual pins for 9v+ and gnd for the 3207 ?....just a bit confused?...cheers guys

[PRR]

What, Google doesn't work for you?

https://www.electrosmash.com/mn3007-bucket-brigade-devices#link61
"MN3207 is based in NMOS technology while MN3007 is PMOS (that is why it needs negative supply)."

Actually, everything is relative. PMOS can be powered zero and plus, but the "gnd" assumption must change.

[deadastronaut]

cheers paul, yup i found that after....

i see....cheers . 

[jjnicola]

So, beeing a PMOS, does it mean that I can't share the power supply with other "normal " pedals?

[bushidov]

Welcome, jjnicola. I believe you are looking at PNP transistor pedals, like fuzzes and rangemasters that don't have an inverter in them. Those don't play with "normal" pedals' power supplies without the aforementioned inverter in them. The PMOS MN3007 vs the NMOS MN3207, in regards to power supply setup, just means what pins get 9V and ground (assuming 9V supply).

On the PMOS MN3007, pin 1 gets 9V, and the "typical" output pins ( pins 7 and 8 ) pullup resistor(s) are also pulled up to 9V and pins 4 and 5 are going to ground.

On the NMOS MN3207, pin 1 goes to ground and the output pins pulldown resistor also go to ground, with pins 4 and 5 going to 9V.

[jjnicola]

Hey thanks for the answer and for the welcome as well.
I bought some mn3007, but I am not sure if are fake or not. Also, i will try to use an Arduino nano to generate the clocks. Will see what happens here.

[Vivek]

Four months or so ago, I redesigned the MN3007 based chorus of the Rockman X100 to use MN3207 instead. This was because of availability issues.

One interesting point was that the Rockman was powered by +/-6V and I thought that its not a good idea to run the MN3207 on those voltages, so I decided to run on +6 and zero.

Then the concepts of what is "ground" and what is Vdd etc had to be clearly understood. I now have
Bipolar driven compressor
driving Unipolar Chorus
driving Bipolar filters etc

But in the end, it worked like a charm, first time. No MN3207 were harmed in the process !!!

and I added stuff that the Rockman X100 did not have, like Rate, Width, chorus delay options.

Tom/Electricdruid helped me with some finer points regarding bias. I sent him a proposed bias schematic snippet and he said "Go for it, Vivek!"

[Vivek]

So, beeing a PMOS, does it mean that I can't share the power supply with other "normal " pedals?

These two issues are not related

If designed properly, you can have it work with other pedals.

In fact, inside the same Chorus pedal, you can have
Pre-BBD filter running on +9 and zero
BBD running on +9 which it considers to be zero for that stage, and zero which it considers to be -9 as far as power supply to BBD goes
and post BBD filter running at +9 and zero

All it needs is some DC decoupling caps at the right places.


I feel:

A) For AC signals, the + and the ground of the DC supply are both " AC Signal Ground" since there should be zero AC impedance between these two.

B) Voltages are relative, so the DC "Potential Difference" between +9 and 0 is same as 0 and -9

We decide which DC wire to call Zero, and  the other one becomes +9 or -9 based on our choice on which one to call Zero

[Vivek]

P.S. Russians say: "Don't you love cats? You just don't know how to cook!" 

What is the meaning of Вы не любите кошек? Да Вы просто не умеете их готовить! ?

[puppiesonacid]

one notable difference between the mn3007 and the mn3207 aside from power, the mn3207 can be clocked up to 200kHz

[ElectricDruid]

one notable difference between the mn3007 and the mn3207 aside from power, the mn3207 can be clocked up to 200kHz

It can fairly easily be clocked to 500KHz before the output starts to drop off, and if you have something that can really drive some current into the clock pins, you can go higher than that. Mark Hammer has mentioned a circuit that pushed it as far as 1MHz. I haven't tried to go that far, but it shows what's possible. The trouble is the clock pin capacitance (same as every BBD!). The MN-series clock chips just aren't that good and as result the datasheet spec's are very conservative. For the same reason, many MN3207-based flanger designs use alternative clock circuits - you can push the chip much higher/shorter with a better clock driver.

[Steben]

one notable difference between the mn3007 and the mn3207 aside from power, the mn3207 can be clocked up to 200kHz

It can fairly easily be clocked to 500KHz before the output starts to drop off, and if you have something that can really drive some current into the clock pins, you can go higher than that. Mark Hammer has mentioned a circuit that pushed it as far as 1MHz. I haven't tried to go that far, but it shows what's possible. The trouble is the clock pin capacitance (same as every BBD!). The MN-series clock chips just aren't that good and as result the datasheet spec's are very conservative. For the same reason, many MN3207-based flanger designs use alternative clock circuits - you can push the chip much higher/shorter with a better clock driver.

Was just about to say the specs of a 3207 make it a flanger chip, the 3007 a chorus chip.

(Unless you make a circuit based around mixing a dry with fixed delay and a normal variable wet delay channel. true zero stuff ... )