MN3007 ADA Flanger Clone Questions

[grathan]

thanks, what's a bbd?

[Paul Marossy]

thanks, what's a bbd?

BBD = Bucket Brigade Delay (chip)

[grathan]

can the bias of the bbd be adjusted by simply turning trimmer # 6?  It looks like that connects to Vcc of mn3007 (ic10).

I guess my original question I shoulda mentioned, will this calibration carry over to 18v?

[Nitefly182]

The BBD Bias is TR1 IIRC.

[Tantalum7]

What is TR6 doing exactly then?  I finally got the flanger tweaked to sound really good now, although nothing in the ADA calibration document mentions TR6 for rev4.  TR6 definitely has a sweet spot and is doing something with the MN3007, but if TR1 is biasing...I'm not quite skilled enough to figure it out from the schematic yet.

Also, has anyone attempted the TZF mod on this build?

[Nitefly182]

I would love to see someone pull off the TZF mod but adding an extra delay line is not something I really know how to do. I think the foxrox does it by delaying the dry signal by a few ms so the other delay line can pass it in the sweep.

[Tantalum7]

Yeah, someone with real skills will have to tackle this.  I can swap a few components here and there, add a stage or a subsection, but this is out of my depth.  I'd love to hear it though.

[mdh]

What is TR6 doing exactly then?  I finally got the flanger tweaked to sound really good now, although nothing in the ADA calibration document mentions TR6 for rev4.  TR6 definitely has a sweet spot and is doing something with the MN3007, but if TR1 is biasing...I'm not quite skilled enough to figure it out from the schematic yet.

This confused me, as well, and then I noticed that there is a cap between the MN3007 and the trimmer, so that trimmer can't have anything to do with DC bias.  Plus, it's on the output of the BBD.  It controls the level of output from the BBD that ultimately gets regenerated and mixed with the dry signal (see the exchange between bajaman and Nitefly182, up this thread).

Glad to hear that you got it calibrated to your liking.  Mine is just in a box now, with a preliminary calibration, but I will be working on it some more in coming days.

[Tantalum7]

This confused me, as well, and then I noticed that there is a cap between the MN3007 and the trimmer, so that trimmer can't have anything to do with DC bias.  Plus, it's on the output of the BBD.  It controls the level of output from the BBD that ultimately gets regenerated and mixed with the dry signal (see the exchange between bajaman and Nitefly182, up this thread).

Glad to hear that you got it calibrated to your liking.  Mine is just in a box now, with a preliminary calibration, but I will be working on it some more in coming days.

I checked a few sources for the info on TR6, but I should have looked in this thread first.  That makes sense now.  I was wondering how to reduce the content of the wet signal in the mix, so now I can tweak that to my liking as well.

As far as calibrating goes, I learned a lot more about how the flanger works by doing a rough frequency set on the clock and then turning trim pots and knobs to see what happens.  If you don't have a signal generator, plug in a guitar and have some patient soul strum for you as you make adjustments.  If nothing else, it gives you something to do until you acquire or find someone with a scope.  It's probably my lack of experience, but I couldn't get any of the numbers to really come up when I was using a scope and a signal generator.  Using the ADA calibration procedure as a rough guide and making adjustments of all the trimmers and pots got me much more pleasing results, but it did take quite a while of testing and turning before the best flanging came out.

[quarara]

Sorry if I bump this thread with some really dumb questions.
In the BOM you can find listed a jack used for external control. Well, I've got two questions about this topic:
- should I use a normal (plastic, preferably) stereo jack or other particular kind of jack?

According to the schematic, it needs to be a stereo jack with at least a switched ring contact.  See Charlie's post at the top of this page here for a part number, but these jacks aren't that uncommon, so you should be able to find others.  They come in both closed frame plastic styles and open frame metal styles.

sorry, but, according with this datasheet and this schematic the correct jack would be 502-12B instead of 502-13B, isn't it?

those jacks will be the death of me.

[moosapotamus]

No. When nothing is plugged into JK3, the wiper of P3 should connect to R53.
502-12B is just a standard stereo jack with no switch. That won't work because when no plug is inserted, the wiper of P3 (manual) will not be connected to R53.
502-13B has a lug that connects to the tip such that when you insert a plug the contact is broken like a switch.
But, the schematic actually shows the switch contact going to the ring, not to the tip.
So, if you use 502-13B, I think you would still connect the switch lug to the wiper of P3. But you would have to swap the tip and ring connections. That would make P3 wiper connect to R53. Then, when you plug in a control pedal, the sweep action of the pedal will just be reversed. Otherwise, if you use 502-13B but do not swap the tip and ring connections, with nothing plugged into the jack, the wiper of P3 would connect to R50 instead of R53.
The jack that I used for JK3 in my build was actually similar to Mouser pn 568-NYS218, which is a stereo jack with a switch on all three contacts, tip, ring and sleeve. I only used the switch for the ring contact.

Hope that makes sense.

~ Charlie

[quarara]

Hope that makes sense.

yes, it does, thanks!
I'm looking forward for the new batch of pcb's!

[gtrgeek1]

Hi All,

I have a few questions for others that have built this MN3007 flanger. I got the unit built up and running with no major problems, but a few small ones that are bugging me. When I check the output on the scope, I see a hell of a lot of clock riding along with the audio. It is really not audible, but should it be there? Since there is no clock cancel on the output of the 3007 or LP filtering, I expect some, but without another one to check I can't be sure.  Has anyone else verified this on a scope?

I am also hearing a slight distortion in a part of the sweep that others have mentioned. It occurs when the clock nears 2.6mhz (through the LFO or when adjusting the manual control to full CW). When I investigated further, there is also a small amount of hum at this top end of the clock. When this happens I get a 1V drop at the input of the regulator (I am using a 24V 80ma supply). The output of the regulator though, stays locked at +15V. It seems that the CD4047 starts pulling much more current when the clock is running that high. When I check the power supply rail, I can see the DC is being modulated by the clock frequency. I have added more filtering to the supply (100n film cap on the output of the regulator, as well as extra 100n monolithics on the digital rail. I also seperated the MN3007 from the digital rail and ran R27 directly to V+. I beefed up the digital ground with a thicker bus wire directly to the main filter ground. All to no avail. Has anyone else seen clock on their V+ rail?

When I trim the unit to a lower clock frequency I get really clean performance, but the flanger does not sweep up to the almost TZF point - which is my favorite part of the sweep. Does anyone have any ideas?

[p.eat]

Hi,

I'm slowly getting along with my build. I have a question regarding some parts subs. I couldn't get the values specified for R28(1M3), R71(14k) and R72(250). Instead I got 1M2, 15k and 255R. Would these substitutions be ok? From looking at the schematic I think so, but I'd like to hear an ok from someone else.

I also bought some MN3007's from my local supplier. They had 4 in stock and each was 0.8 Euros. Yeah! The salesman (a really old guy) didn't even know they had them in stock and mentioned he can't remember ever selling one of these.

thanks,

Peter

[oldschoolanalog]

gtrgeek1: I just got a 'scope & function generator so I'll be able to check out the things you mentioned tommorrow. I will however be looking at a unit w/an SAD1024 as I haven't found the time to finish my 3007 build. It's the same layout (except for the BBD & associated parts) so I'll have a look and report back.
p.eat: Your substitutes are within 10% of the parts specified so I don't think there should be any problem.

Dave

[oldschoolanalog]

When I check the output on the scope, I see a hell of a lot of clock riding along with the audio. It is really not audible, but should it be there?  Has anyone else verified this on a scope?

I did a quick look/see on my 'scope, and yes, there is some clock riding the audio at the output. Not a "helluva lot"; but it is there. While it is not audible, I don't know if it belongs there. I'll have to do more testing Sun., as work has gotten the better of me these last few days .

I am also hearing a slight distortion in a part of the sweep that others have mentioned. It occurs when the clock nears 2.6MHz (through the LFO or when adjusting the manual control to full CW). When I investigated further, there is also a small amount of hum at this top end of the clock.

I agree that it is very slight. However, in a live situation, playing with a full compliment of musicians, you can't hear it. Or I should say I can't hear it.  Heck; when one is putting this (or any effect for that matter) through the paces all alone in your quiet shop, any and all quirks are significantly magnified. I am not saying this is OK, however, certain things must be taken "with a grain of salt". I have "one or two"  different flangers,
and some exhibit more noise at the top of the sweep (shortest delay) than at other points of the sweep.
http://i175.photobucket.com/albums/w121/oldschoolanalog/DSC00806.jpg

When this happens I get a 1V drop at the input of the regulator (I am using a 24V 80ma supply). The output of the regulator though, stays locked at +15V.

At least this proves the V reg is doing it's job... 

Has anyone else seen clock on their V+ rail?  Does anyone have any ideas?

I'll check this out as soon as I have a chance.
In closing (for now), I would like to say that while the A/DA flanger is a great flanger for guitar, It is not exactly a piece of high end audio equipment. It's not a panacea. It has its inherent quirks. One might just have to learn to live with them...
You want high end audio? Clone an Eventide !
Or, this looks pretty cool...
http://home.debitel.net/user/jhaible/jh_storm_tide_flanger.html

Hang in there; we'll get this all sorted out...
Till next time,
Dave

[Nitefly182]

When I check the output on the scope, I see a hell of a lot of clock riding along with the audio. It is really not audible, but should it be there?  Has anyone else verified this on a scope?

I did a quick look/see on my 'scope, and yes, there is some clock riding the audio at the output. Not a "helluva lot"; but it is there. While it is not audible, I don't know if it belongs there. I'll have to do more testing Sun., as work has gotten the better of me these last few days .

I am also hearing a slight distortion in a part of the sweep that others have mentioned. It occurs when the clock nears 2.6MHz (through the LFO or when adjusting the manual control to full CW). When I investigated further, there is also a small amount of hum at this top end of the clock.

I agree that it is very slight. However, in a live situation, playing with a full compliment of musicians, you can't hear it. Or I should say I can't hear it.  Heck; when one is putting this (or any effect for that matter) through the paces all alone in your quiet shop, any and all quirks are significantly magnified. I am not saying this is OK, however, certain things must be taken "with a grain of salt". I have "one or two"  different flangers,
and some exhibit more noise at the top of the sweep (shortest delay) than at other points of the sweep.
http://i175.photobucket.com/albums/w121/oldschoolanalog/DSC00806.jpg

When this happens I get a 1V drop at the input of the regulator (I am using a 24V 80ma supply). The output of the regulator though, stays locked at +15V.

At least this proves the V reg is doing it's job... 

Has anyone else seen clock on their V+ rail?  Does anyone have any ideas?

I'll check this out as soon as I have a chance.
In closing (for now), I would like to say that while the A/DA flanger is a great flanger for guitar, It is not exactly a piece of high end audio equipment. It's not a panacea. It has its inherent quirks. One might just have to learn to live with them...
You want high end audio? Clone an Eventide !
Or, this looks pretty cool...
http://home.debitel.net/user/jhaible/jh_storm_tide_flanger.html

Hang in there; we'll get this all sorted out...
Till next time,
Dave

I definitely agree with the "it is what it is" outlook on this project. Its a late 1970s analog modulation pedal and it has some quirks. Its on of the gems from that era and you can definitely get it sounding awesome with a little tweaking.

[cathexis]

You want high end audio? Clone an Eventide !
Or, this looks pretty cool...
http://home.debitel.net/user/jhaible/jh_storm_tide_flanger.html

Now, THIS makes me salivate. I wish someone with the brains for the task would figure out a way to adapt this circuit for the 3007 like with the A/DA. That would make my summer vacation so much more nerdy and isolated 
Seriously, PLEASE! Anyone?? I'd do anything not to mess with those nasty SAD1024:s, they make me damn nervous.

On another note, I just finished my expression pedal for the A/DA flanger. I used an old crybaby with the original 100K pot, and mounted the jack as per the moosapotamus schematic. Pretty cool, but I want to tweak it for a bit, not that happy with the sweep. Also, it seems backwards to me, I think I'd like the action the other way. I'm going to fool around with this a bit more, some tapering resistors, maybe.

LARS

[StephenGiles]

I get panacea sometimes after eating a vindaloo!!!

[oldschoolanalog]

I get panacea sometimes after eating a vindaloo!!!

Feel the burn...