A Fantastic analog Flanger !!

[WildMountain]

Sorry Any, I'm quite fond of this one myself. It was my first analog delay at the time.
STM: I know there is an IC below the metal bar, not sure if it's an MN3005 but I think so.
I'll try to open it up again somewhere the next couple of days to do some further investigating. Might start a new thread about it, as it is not only an intrigueing design, but also one that sounds fantastic.
You'll have to bear with me because of my "newbie-ness" in these kinds of effects. Delay, bucket brigades, etc, are things way too complicated for me.
I'm intrigued by the absence of the fuse. The pedal is in working order as it is.

[whythisreason?]

Pics of the FL-01 can be found here:

http://www.anytheband.com/images/FL-01components.jpg

http://www.anytheband.com/images/FL-01trace.jpg

They are large close up pics, so be prepared to wait for loading...
I'll make a partslist and layout when I get the time,
prob. somewhere in the next few weeks.

[Ben N]

It states you can "make steel drum effects" by cranking the feedback,
setting speed and depth to zero and tune to freaquenty with the manual knob.

Sounds sort of like stuff you can do with the filter matrix setting on a Deluxe Electric Mistress and a little palm muting.

Ben

[stm]

Pics of the FL-01 can be found here:

http://www.anytheband.com/images/FL-01components.jpg

http://www.anytheband.com/images/FL-01trace.jpg

They are large close up pics, so be prepared to wait for loading...
I'll make a partslist and layout when I get the time,
prob. somewhere in the next few weeks.

Nice!  I think the pictures after some processing would allow tracing the schem.
Just some questions:

1) What are the transistor names (to define pinout for drawing)
2) What are points labeled (A), (B), (C), (E) and (F)?  Do they have soldered wires or are they just test points?
3) I don't see point (D) in the image.  Does it exist?
4) Are all the four external pots and power connected via the 7-pin connector on the left?

Regards,

STM

[Mark Hammer]

Um, are we sure this is the correct FL-01?  You will note the presence of the number KLM-2800 in the corner of the board ( http://www.anytheband.com/images/FL-01trace.jpg ).  That would normally indicate a Korg PCB.

[whythisreason?]

First of all, the YAMAHA **-01 and Korg **-01 are the same product line as Maxon was to Ibanez.
So yes, a lot of yamaha boards actually have a korg equivalent. (I have both the Korg and Yamaha CH-01 chorus for example)

Second, I'll trace the schem somewhere in the near future as well as note all the correct resistor values, IC's, trannies, caps etc.
(I'll do that first in case someone feels like tracing the pcb) The "A" to "F" points are for the footswitch cable connections,
the pots are wired directly on to various points on the pcb (solder side) I took detailed photo's and will post where they should be made.
(point D is hidden between some resistors in the middle of the board btw)
(I'm very busy rehearsing for a solo gig next sunday...just me on stage performing my own songs, anyway...)

I've put up a huge (577k) "high contrast" PCB scan here:

http://www.anytheband.com/images/fl-01pcb-large.jpg

Hang in there, we'll get it sorted!

[Mark Hammer]

First of all, the YAMAHA **-01 and Korg **-01 are the same product line as Maxon was to Ibanez.
So yes, a lot of yamaha boards actually have a korg equivalent. (I have both the Korg and Yamaha CH-01 chorus for example)

Well you learn something new every day.  I was not previously aware of that product equivalence (Yamaha/Korg).  Thanks!! 
You've earned your salary today.

[whythisreason?]

Ain't that cool?  (they even look almost identical, the korg's are a bit more square looking)
BTW the PCB has some traces doubled on the ground lines most obviously.
They are not second layer nore are they (what looks like it in the picture) splitting two traces apart.
If there is any doubt I'll mark them on the pic.

[Eb7+9]

the Nipponese are known for rebranding their effect series ... In the early days Shin-Ei - Jax - Bruno - Royal - Ibanez and later Roland - Korg - Yamaha - Boss - Pearl - Maxon - Guyatone ... in some cases identical designs, and some schematics done by the same art dpt - always wondered about that ... I'm curious to know what's different about the Yamaha mkII series in the end

jc

[Mark Hammer]

The various Shi-Ei equivalences I was aware of, as well as Maxon-Ibanez.  In some cases these are simply remarketed products under another name, similar to the various Marshall amps sold in different music store chains, like Park and Narb.  But there are other equivalences that come as complete surprises.  Certainly Yamaha/Korg comes as one because these are both such large companies.  It's a bit like finding out that a Dodge van is made by Ford.

BTW, JC, spooky about that ferry sinking near Prince Rupert last night.  Latest word is that everyone was rescued.

[Eb7+9]

... didn't hear about it yet - holy !! trip back from Haida Gwaii once was roughest waters I've ever been in - bad weather cancellations for a whole week before that ... on that one nite the slamming of the waves was so rough, you could count to three from the drop at the crest to the smash at the bottom, vehicles parked in the ferry hold were bouncing around and hitting each other - almost everybody throwing up, lots of crying and weirded out looks - that was one long nite ... makes you wonder how the Haida's crossed that 90 miles in their dugouts on their way to pillaging other tribes along the coast ...

I have a friend who miraculously survived three days in these waters after sinking his fishing boat - it's also a place where this other man I've heard of takes troubled youth out for a survival trip, makes them hang outside in storms at nite and face themselves - a little crazy but apparently it works ...

glad the people got saved - yikes !

ok, back to Flangers ...

[whythisreason?]

The Korg FLG-1:

http://filters.muziq.be/model/korg/1/flg1

The Yamaha FL-01:

http://filters.muziq.be/model/yamaha/01/fl01

BTW, filters.muziq.be is a great site runned by a belgian guy, go have a look!
(I contributed some pictures to his database for various effects)
Note the similarity between the pedals?

[Mark Hammer]

... didn't hear about it yet - holy !! trip back from Haida Gwaii once was roughest waters I've ever been in - bad weather cancellations for a whole week before that ... on that one nite the slamming of the waves was so rough, you could count to three from the drop at the crest to the smash at the bottom, vehicles parked in the ferry hold were bouncing around and hitting each other - almost everybody throwing up, lots of crying and weirded out looks - that was one long nite ... makes you wonder how the Haida's crossed that 90 miles in their dugouts on their way to pillaging other tribes along the coast ...

I have a friend who miraculously survived three days in these waters after sinking his fishing boat - it's also a place where this other man I've heard of takes troubled youth out for a survival trip, makes them hang outside in storms at nite and face themselves - a little crazy but apparently it works ...

glad the people got saved - yikes !

ok, back to Flangers ...

Not just yet.... http://www.cbc.ca/story/canada/national/2006/03/22/bc_ferry060322.html

[MR COFFEE]

Guys, before you go to all the trouble to trace out the flanger schematic, I've got one.

I didn't know the Yamaha-01 and the Korg FLG-1 were the same puppy or I would have offered it sooner.

Anybody that wants one, send me your email. 

Not to dampen anyone's joy in playing through a good flanger, but there is very little unique about the design, except that there are a couple of back-to-back diodes in series with a 4.7K resistor in the pre-3007 filter feedback loop that provide slight waveform compression to soften the input overload characteristics. It's in parallel with a 10K resistor, so it's pretty mild "clipping" (I hesitate to even call it "clipping" when it's that mild).

The clocking circuitry is modulated by a pretty plain vanilla tri-wave oscillator, which does have a slightly different interface to the MN3101 clock driver using a couple of transistors and could result in some interesting warping of the clock sweep modulation. It'd be nice if somebody out there who's got one could check out the frequency sweep and see if it is hyper-triangular or similar.

[stm]

Guys, before you go to all the trouble to trace out the flanger schematic, I've got one.

I didn't know the Yamaha-01 and the Korg FLG-1 were the same puppy or I would have offered it sooner.

Anybody that wants one, send me your email. 

Not to dampen anyone's joy in playing through a good flanger, but there is very little unique about the design, except that there are a couple of back-to-back diodes in series with a 4.7K resistor in the pre-3007 filter feedback loop that provide slight waveform compression to soften the input overload characteristics. It's in parallel with a 10K resistor, so it's pretty mild "clipping" (I hesitate to even call it "clipping" when it's that mild).

The clocking circuitry is modulated by a pretty plain vanilla tri-wave oscillator, which does have a slightly different interface to the MN3101 clock driver using a couple of transistors and could result in some interesting warping of the clock sweep modulation. It'd be nice if somebody out there who's got one could check out the frequency sweep and see if it is hyper-triangular or similar.

Hi Mr. Coffe, please send me a copy to stepper(at)ing(dot)puc(dot)cl THANKS!

Commenting the circuit from what I had already grabbed from the board images, two things have attracted my attention (this is concentrating in the LFO/CLOCK/BBD sections):

1) The BBD clock lines have 51 ohm resistors in series each.  This may soften the driving of the clock lines, don't know if it impacts the BBD sound, reduces the clock spikes at the outputs, or maybe was just an extra precaution to have the MN3101 run more alleviated since, in the MN3101 datasheet such resistors are recommended if driving more than 4096 stages to avoid overheating.
[EDIT: these two 51 ohm resistors--R37 and R38--do not appear in the KORG schematic!  Were they useless and finally removed or do they add some mojo to the sound?]

2) There are three (03) diodes plus two transistors in the MN3101 interface with the LFO.  I checked Boss Flanger and Chorus schematics, as well as other makers, and none had that many diodes in the LFO/CLOCK interface.  This may be there to introduce some warping (hypertriangularity) to the sweep perhaps.

Regarding the two "clipping" diodes in the audio stage prior to the BBD, they are a common practice to avoid oscillation when high levels of regeneration are used.  You can see them in Boss flangers (BF-2 and HF-2) also.  O course as a side effect they introduce some compression, harmonics and clipping.

Bye for now!

[whythisreason?]

I'll post all part values for comparison between FL-01 and FLG-1, I was almost done anyway... 
(mayebe they just shared the pcb but used partvalues to their respective tastes?

Partslist for the FL-01 can be found at:

http://www.anytheband.com/images/FL-01partslist.txt

[stm]

Thanks for posting the values!  I did a comparison and the following table summarizes the differences I could find:

[UPDATED]


[UPDATED]
Items in RED are clear differences.  Items in BLUE are something to further inverstigate, since apparently the Yamaha value is incompatible for the Korg use of this resistor. R2 connects to the node formed by R3 & R10, while its other end goes to the 7-pin connector.  Basically R2 allows summing an external voltage to control remotely the Manual setting of the effect, probably by means of an expression pedal. It doesn't affect normal operation and this difference can be disregarded, since KORG devices don't have this modular connector.

Main differences are on the filter capacitor values, both for the upper and lower frequencies (see those 1u changed to 0.1u?--R8 & R16).  Also, it seems the two summing resistors for the dry and wet paths (R11 & R18) on the Korg schem were more carefully selected, perhaps to compensate for a slightly over unity volume when the effect is engaged.  This leads me to believe that the Korg unit might be a later revision and the Yamaha the original.  Another aspect supporting this are some capacitors (c24 and c25) that didn't exist on the Yamaha version, thus were added later to provide extra filtering.  The fact of removing the two 51 ohm resistors in series with the clock lines makes sense since the datasheet recommends them only for BBD's with more than 4096 stages (i.e. when a single MN3101 is driving two MN3005's).

Two aspects seem unique to this LFO design.  First, the triangular wave is extra filtered by R43+C17 with a cutoff frequency of 1 Hz.  This is certainly an aid when the device is used at high modulation speeds for effects such as chorusing and leslie, turning the triangle shape into a milder waveform.  I think this is key to the good sound reported.  Second, the three diodes in the emitter of Q2 add some nonlinear feedback to the modulation, which might be there to have a more uniform sweep (into the hypertriabgular territory).  This last statement is yet unverified, but makes sense with the special sound reported for this circuit.

An interesting question now rises: which of the two versions is better?  These gems are rather scarce, so it might be difficult to be able to make a side by side comparison between a Yamaha and a Korg version.  Also, proper biasing of the BBD is crucial for good sound.  I've read before in the context of the CE-2 that many "average" sounding units sounded superb after retrimming the bias.  This means if someone ever has the chance to make such a comparison, proper biasing must be ensured on both devices under test for the results to be valid.

As a closing comment, all the 10k resistors installed on the (+) input of the audio opamps are useless and could be replaced by jumpers, since the opamps (TL062) have JFET inputs thus said resistors don't make any difference in terms of offset voltages.

Regards,

STM.

[whythisreason?]

R2 is connected from R3 to the middle pin of the 7pole "molex type" modular connection.
(since the Korg's weren't modular this resistor is indeed unused)

R11 is correct
R18 is correct
R21 is correct
R34 is correct
R44=150k (corrected)
R45=3k4 (corrected)

the rest is as stated,
(board revision is KLM-280D FL-01)

[Arn C.]

MR. COFFEE,
   Please send the schematic my way:  arn.conklin@ametek.com

Thanks a bunch!
Arn C.

[Dai H.]

the schemo was part of that Korg schematics set someone kindly uploaded a while back. I've got a flanger(Yamaha), a chorus, and a POS Hardist (worst kind of overcompressed hair metal type distortion) which I cannibalized for the case(?--I think I had a stripped out batt. screw insert in either the chorus or flg.). The flanger is good, as well as the chorus (IMO). There are two ver. of the chorus--one has a little slide switch, which makes the sound "wobbly"--the other one doesn't have the sw. One of them developed a 'chirp' when switching which I need to fix. Also, Yamaha as part of this series did have a giant pedal board so you could hook all of them up (and prob'ly have presets--Boss had something like this in the 80s so I imagine it was meant to compete with them). Plus I've seen a much smaller ver. where you could hook up 3? of them plus a footpedal for continuous control of something.