Byzantium Flanger (Boss BF-2)

MichaelW

Well-known member
Build Rating
5.00 star(s)
Just buttoned up this build after supper this evening.

I've never owned a flanger. I can probably count on one hand how many times I've actually played through one.
And on NO hands I've played through an all analog one!

(I think the last time I used a flanger was in some Digitech multi-fx pedal board thingy I had at one time)

So needless to say I have very little experience with them. I've been wanting to build the Byzantium for quite some time and it's been
in and out of my cart at least a dozen times. It looked complex and the parts size requirements gave me a headache just thinking about it.

Well, I couldn't have been more wrong. It was actually a fairly straightforward build. Like building two modest effort boards simultaneously.
And since I recently built the Tourbus I already was mostly there with the low profile components needed. Again, big shoutout to @PedalPCB for his elegant layouts. Lots of room to work and nothing feels crammed.

The only low profile components I couldn't find were the 47u e caps. I had ordered some 47u Tantalums and was planning to use those but turns out they weren't any more "low profile" than the electrolytics I already had. So in order to make it all work I had to use a bit of "English" with the 2 47u caps. Everything else, I was either able to get in low pro size or I used tantalums. The only other substitution I made was for the single PNP. BOM called for a BC560 which I couldn't find so I used a 2N5087 (which has reverse pin outs to the BC560 btw). I socketed the PNP in case it didn't work but it all seems to work just fine.

Like my Tourbus, I used the @Betty Wont method of bias trimming, I just set all the trimmers to noon, plugged it in and heard the whooooosh of jet airplanes! I couldn't find any info on biasing to setting the other trimmers, and it sounds so good I'm probably just going to leave it the way it is. I can't imagine getting it to sound more flangey than it already is.

I can get everything from light chorusing to the whole jet airplane sounds from this thing. Rich, lush and chewy flanging. Still trying to figure out what all the knobs do, especially the "manual" control, not sure what that does. But I only had about 30 minutes play time with it so far.

The only downside to this build is the enclosure. Really unhappy with these cheap enclosures I recently got from both Smallbear and I think this one I used was from Stompbox. I had run out of 125b's at one point and threw them in my parts order. The powder coating is really poorly done. Scratches super easily and it chipped on me when I was holding it down to drill. (One of the corners not in the picture).

Needless to say, after I get through these enclosures, I'll be using Tayda or my own painted ones from here on out. I wished I'd had a violet enclosure for this build but alas I didn't. Since it's a wild kind of sound I decided to go with the garish look of the bright orange knobs and an orange LED. I think it all works.

I'm enjoying the heck out of this pedal and looking forward to building the other two flanger boards I have, the MPB Colossalus and the @Chuck D. Bones Electric Ladyparts flanger gifted to me by our ever generous @fig.

You can see all the fine scratches in this box, just from drilling and building it. I hid the chipped corner. I'm planning to raid my wife's nail polish stash tomorrow.
IMG_3529.JPG


Before stacking......lots of room and relatively low component count on each board. It's not as crowded or complex as it might appear.
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All put together....
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Shame they JUST ran out of 125's LMS , I got 1 each 125 and BB coming soon. might be able to get a purp for your collo or electric lady! the rest is impeccable as always Mike. sideways bends work but think Digi also carries the shorty Alum E's besides the better sized tants, at least in 10v's. I'm gonna guess 'manual' is likely tied to the lfo and whether it sweeps through or echoes akin to a reverb.
 
Shame they JUST ran out of 125's LMS , I got 1 each 125 and BB coming soon. might be able to get a purp for your collo or electric lady! the rest is impeccable as always Mike. sideways bends work but think Digi also carries the shorty Alum E's besides the better sized tants, at least in 10v's. I'm gonna guess 'manual' is likely tied to the lfo and whether it sweeps through or echoes akin to a reverb.
I actually found some low pro 47u's at Mouser. (After the fact of course)
These would have just squeaked in.
Also re-stocked on some 100u caps that I always seem to need.
Now if I could find a reliable source for some low profile slim 1u Film caps I'd be happy!

Ok, I looked through my records, this red enclosure did come from Smallbear not Stompbox (sorry Ross:)
I got them because they were cheap. ($4.75) Sometimes you roll the dice and lose....sigh.
 
Clean build as always. For some reason I always thought you would have to solder the two boards to eachother, I forgot about those little connectors. Was it a chore at all to get the pins lined up?
 
Clean build as always. For some reason I always thought you would have to solder the two boards to eachother, I forgot about those little connectors. Was it a chore at all to get the pins lined up?
Not at all, I just used pin headers and cut them off 2 at a time. (Not recommended, they don't cut well) As long as you solder them on straight.
Then put the male headers into the soldered female headers, then place the top board on top of that and solder in place viola.

The 3PDT switch is soldered to both boards. (Meaning 3DPT breakout board and top PCB) I gave some thought to trying to make that also with pin headers or molex connectors but there's just not enough room. So if I had to remove the top board for troubleshooting I'd just need to take the 3dpt out along with it.
 
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That looks excellent! Very nicely done!

The stacked projects look more intimidating than they actually are. Realistically the only differences between them and any other project are the low-profile component requirement and connecting the 3PDT breakout board to the top PCB instead of the lower PCB like most projects. (same idea, but the pinheader goes on top of the 3PDT breakout instead of below)

If you use male/female pinheaders (as you should) the boards just plug together easily.

In the event any troubleshooting is required you can connect the two boards together side-by-side on the bench with male/female breadboard jumper wires.

And yep, like @MichaelW said, just remove the nut from the footswitch and the top layer lifts out.
 
That looks excellent! Very nicely done!

The stacked projects look more intimidating than they actually are. Realistically the only differences between them and any other project are the low-profile component requirement and connecting the 3PDT breakout board to the top PCB instead of the lower PCB like most projects. (same idea, but the pinheader goes on top of the 3PDT breakout instead of below)

If you use male/female pinheaders (as you should) the boards just plug together easily.

In the event any troubleshooting is required you can connect the two boards together side-by-side on the bench with male/female breadboard jumper wires.

And yep, like @MichaelW said, just remove the nut from the footswitch and the top layer lifts out.
I think this was your first introduction to a PedalPCB Dual Board in 2018!
How many have been built, that Nu-Tube was expensive! :
 
That looks excellent! Very nicely done!

The stacked projects look more intimidating than they actually are. Realistically the only differences between them and any other project are the low-profile component requirement and connecting the 3PDT breakout board to the top PCB instead of the lower PCB like most projects. (same idea, but the pinheader goes on top of the 3PDT breakout instead of below)

If you use male/female pinheaders (as you should) the boards just plug together easily.

In the event any troubleshooting is required you can connect the two boards together side-by-side on the bench with male/female breadboard jumper wires.

And yep, like @MichaelW said, just remove the nut from the footswitch and the top layer lifts out.
@Robert is there any specs or guidance on the trimmer settings before I put screws in the enclosure? I mean it sounds awesome but then I don't know what I don't know.....y'know? heh
 
@Robert is there any specs or guidance on the trimmer settings before I put screws in the enclosure? I mean it sounds awesome but then I don't know what I don't know.....y'know? heh
The dearly departed blackhatboojum posted his/Boss’ calibration instructions on here somewhere, just do a search for Byzantium and you will more than likely find them. The WIMA 1uf film caps from Tayda work just fine for stacked builds. I think I ended up bending my electros on my build simply because it was what I had on hand and didn’t feel like digging for buried treasure in Mouser. Think that was ab the time Smallbear closed shop which is where I got my previous low pro electro (🧐 I claim that band name…). Nice job on the build BTW. @Robert ’s fine board layout makes these stacked board projects much less intimidating.
 
The dearly departed blackhatboojum posted his/Boss’ calibration instructions on here somewhere, just do a search for Byzantium and you will more than likely find them. The WIMA 1uf film caps from Tayda work just fine for stacked builds. I think I ended up bending my electros on my build simply because it was what I had on hand and didn’t feel like digging for buried treasure in Mouser. Think that was ab the time Smallbear closed shop which is where I got my previous low pro electro (🧐 I claim that band name…). Nice job on the build BTW. @Robert ’s fine board layout makes these stacked board projects much less intimidating.
I actually ordered some of those 1uf "low pro" film caps from Tayda but what I got was the standard tall size same as the Kemets I get from SPB.
Not sure if they screwed up the order or what but too much of a hassle to do anything about.
Which ones did you order from Tayda?
 
The dearly departed blackhatboojum posted his/Boss’ calibration instructions on here somewhere, just do a search for Byzantium and you will more than likely find them. The WIMA 1uf film caps from Tayda work just fine for stacked builds. I think I ended up bending my electros on my build simply because it was what I had on hand and didn’t feel like digging for buried treasure in Mouser. Think that was ab the time Smallbear closed shop which is where I got my previous low pro electro (🧐 I claim that band name…). Nice job on the build BTW. @Robert ’s fine board layout makes these stacked board projects much less intimidating.
Ok, I found the calibration specs on the MadBeans build docs....sounds complicated....heh. I'm gonna play it some more and see if I can hear clipping or other issues before delving into this. Might just leave it with the @Betty Won't settings.
 
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