HF-2 Blackhat Edition flanger

[blackhatboojum]

What do you do when you get a handful of MN3204 BBDs? Well… You build a Boss HF-2 flanger of course. Now, some of you may be asking the question… “Didn’t you say you were done building for awhile in your BF-2B build report Mr. Blackhat?” You’re right. I did but, what you didn’t know is, I had actually done a pcb layout of a standalone HF-2 board at the same time. Since I finally got my grubby paws on some MN3204 goodness, and my HF-2 Blackhat Edition pcb was already at my disposal, I had to build it.

There’s not much more I can add to this build report that I haven’t said already in previous ones so, I’m just gonna drop in the pics and call it day. Thanks for looking.

 

[Paradox916]

Hands down dark lord of the flanger! Killed it again!

 

[Bricksnbeatles]

Awesome build!

I’ve only seen the schematics for the HF-2, but I was always under the impression that the HF-2 and the BF-2B were identical circuits, just one marketed towards bassists and one towards guitarists. Are there actually any different values between the two?

 

[Bucksears]

Looking at the schematics side-by-side, these are the only differences I can see:

HF-2
R10 22K
CLOCK TRIM 1MB
R46 100K

BF-2B
R10 39K
CLOCK TRIM 470KB
R46 330K

That said, it's believable, based solely on reviews/feedback from users, that the two circuits are similar; many complaints (if you want to call them that) are that the BF-2B is too subtle. On the flip side, that's the major compliment of the HF-2.

 

[blackhatboojum]

Awesome build!

I’ve only seen the schematics for the HF-2, but I was always under the impression that the HF-2 and the BF-2B were identical circuits, just one marketed towards bassists and one towards guitarists. Are there actually any different values between the two?

Thanks! When I referred to the BF-2B, I was actually referring to my Blackhat edition of the standard BF-2 flanger. Which is just that. A Boss BF-2. I can answer your question though, and the difference is just one capacitor value. The cap into the second op amp stage on the HF-2 is 47nF. On the BF-2B it’s 10nF.

Now, the differences between the BF-2 and the HF-2/BF-2B are a little more interesting. The obvious one is the BBD, which most of us are already aware of. The feedback resistor value on the BF-2 is 39k. The HF-2 is 22k. The clock trimpot on the BF-2 is 500k and on the HF-2 it’s 1 meg. The resistor following the trimpot is 300k on the BF-2 and 100K on the HF-2. The HF-2 also has an additional power filtering stage after the voltage regulator. There’s a 33ohm resistor and then a 47uF cap to ground. The clock chip, BBD, clock trim pot, and associated transistor pull power from this node whereas, the BF-2 does not.

 

[Bucksears]

You should be able to build both a BF-2 and an HF-2 from the HF-2 layout. I like the power filtering, and I was going to build a BF-2 to use for bass (Simon Gallup of The Cure reportedly uses one), but I like the bass on my Zoom multi-fx for flanging now.

 

[Gordo]

I wanted to build the HR on your board but found out the hard way that the chips are pretty much unobtainium at this point.

 

[blackhatboojum]

I wanted to build the HR on your board but found out the hard way that the chips are pretty much unobtainium at this point.

Yes they are. I took a chance and bought 5 of them from Utsource. I was honestly expecting relabeled MN3207s but, surprisingly they’re not. They’re definitely used and pulled from something else but, they all work.

 

[Gordo]

I bought in and picked up one from UTSource. I honestly don't expect it to be legit but threw all caution and common sense to the wind. I'm finally getting around to building up the BF-2 board and since my Cabintech chip came up as a dud I figured why not. I can't prove it didn't ship as a working chip so haven't challenged CT on it because they've been SO good on everything I've purchased from them.

Still, on the odd chance I get an HF-2 out of this...

 

[Gordo]

Board is done with the mod parts. Needs calibration yet but I'll be damned if this thing works as an HF. It definitely sounds different than the stock 3102 and I really like the fact that the bottom end seems untouched. Very subtle, this one is.

We won't talk about what I paid for shipping for what was essentially a reasonably priced 3204. Especially since I'm allergic to snake oil. I think I might have done OK.