Has anyone sniffed around the holy fire in the last few years?

Started by ScottB, January 10, 2011, 04:44:11 PM

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ScottB

I am aware of the whole redeemer post, don't want to resurrect what became unnecessarily hot. But at the end, there was an implied promise to release a little more technical info. It's been about 5 years, just wondering if I missed anything? Any speculation over the years?

My reason is just pure curiosity. It sounds (from their press) like they are really proud of "finding a new way to do something using old analog computer technology" to paraphrase.

Okay, so call me intrigued. I have a holy fire, it is a nice cleanish overdrive that goes well with bass. It works fine, I don't want to play with it or duplicate it. Looking inside I see the rows of clipping(?) LEDs, and some other junk, and a potted portion. Now, the press blurbs about "50's and 60's analog computer technology" sound cool in a mad scientist kind of way, and the potted portion to me does resemble what might be two end-to-end bucket brigade memory modules. And BBs do have low pass filtering for the clocks. And there is a dirty side to some BB style delays because of lack of headroom, but i don't know if that is a function of the BB or the parent circuit, or how much. And they do (in their press) talk about waveforming rather than clipping. And if the redeemer mojo carries over to the holy fire, this would exclude FETs and op-amps (IC op-amps at least). Plus there is the matter of the 48V power supply...

tl;dr
Any guesses by now as to what the holy fire circuit is doing and is it kind of unique/elegant/whatever?





Jhouse

Wow. Thank you for saying something about this pedal. I have never heard of it before and it really caught my interest.

I'm sure the 48v power supply gives it an amazing amount of headroom. That could be how it gets so clean.

caress

why don't you post a gutshot and/or de-goop it and i'm sure we could put to rest whatever mysticism surrounds it.

Quote from: ScottB on January 10, 2011, 04:44:11 PMIt sounds (from their press) like they are really proud of "finding a new way to do something using old analog computer technology" to paraphrase.

Now, the press blurbs about "50's and 60's analog computer technology"

that to me sounds like marketing bullshit!  you know what used to be analog computer technology?  tubes.  i don't hear fender claiming to use analog computer technology...

Jhouse

Quotewhy don't you post a gutshot and/or de-goop it and i'm sure we could put to rest whatever mysticism surrounds it.

Agreed. Open that bad boy up!

ScottB

Quote from: Jhouse on January 11, 2011, 11:46:35 AM
Quotewhy don't you post a gutshot and/or de-goop it and i'm sure we could put to rest whatever mysticism surrounds it.

Agreed. Open that bad boy up!

Is that okay with the mods? The FAQ's generally suggest not posting schematics without knowing first, but how does that apply to open boxes? I like this too much to de-pot, I'm just curious if there is something different going on. I just don't want to violate the forum standards.



ScottB

Quote from: caress on January 10, 2011, 08:35:40 PM
...
that to me sounds like marketing bullsh*t!  you know what used to be analog computer technology?  tubes.  i don't hear fender claiming to use analog computer technology...

Really there are plenty of people still using tubes today to surf the net, right? That is kind of pat answer discussion i wanted to avoid; as far as it being marketing hype, oh yes indeed, but entirely bullshit? No, because this is exactly what a lot of bucket brigade delays are doing. Tubes never lent themselves to high speed boolean function (but they were present in the large drum drives, i don't know why). Bucket brigades were the way to build a "discreet component" microprocessor.

Which is the intriguing part. It is a pretty nice little pedal in my (non-musically proficient) opinion. Should I go scrounging magnavox chroma delays out of old TVs? Ha!




slacker

Quote from: ScottB on January 17, 2011, 12:29:51 PM
Is that okay with the mods? The FAQ's generally suggest not posting schematics without knowing first, but how does that apply to open boxes? I like this too much to de-pot, I'm just curious if there is something different going on. I just don't want to violate the forum standards.

Posting pictures of pedal guts is fine.

ScottB

well this is going to take a little more surgery to get apart, I can't find any of my small screwdrivers. Dang kids!

Plus I don't know how well pics will come out with what camaras i have available, but working on it.


Johan

Quote from: ScottB on January 17, 2011, 12:29:51 PM
Quote from: Jhouse on January 11, 2011, 11:46:35 AM
Quotewhy don't you post a gutshot and/or de-goop it and i'm sure we could put to rest whatever mysticism surrounds it.

Agreed. Open that bad boy up!

Is that okay with the mods?

in the past, a few builder have asked that their schematics didnt get circulated through the forum. later when they found that wish was respected, they changed their minds...but when in doubt, ask Aron. it's his forum and he makes the rules
DON'T PANIC

ScottB

Sent a PM to aron just to make sure. Sorry to make you guys wait but these are really crappy pics, and I am going to have to locate a good loop to give specifics because I am too old to see the tiny writing. There are two flavors of mystery meat in this taco, one is a 6-pin IC which appears to have had the silk screen removed and marked for orientation, plus the potted portion which is 5 leads and reminded me of a bucket brigade, which is what got my imagination rolling.





Jhouse

I feel like a little kid at Christmas waiting for this thing.

Johan

Quote from: ScottB on January 17, 2011, 03:00:31 PM
There are two flavors of mystery meat in this taco, one is a 6-pin IC which appears to have had the silk screen removed and marked for orientation, plus the potted portion which is 5 leads and reminded me of a bucket brigade, which is what got my imagination rolling.

I know there are a few opto-ic's like that...a led on one side and usualy a BJT with an optical base on the other. but sometimes they have a FET with optical gate. perhaps this device is related to the old "Expandora"? wich used such ic for pick attack sencitivity...
J
DON'T PANIC

ScottB

I guess nothing wrong with a quick rundown of parts that I can ID

The one mystery IC just needed a loop and a flashlight applied so I could see it.

Two boards, very elegantly arranged. Whole thing is top notch. I really wish the LEDs fit the logo better for aesthetics, but it is a pedal not a light show. Case is a custom clamshell design, the back and L/R sides come off, while the top and T/B sides hold all jacks and pots, which in turn hold the two PCBs. There is room for two 9V batteries in this config (I think) and it might inspire someone trying to fit an 18V creation into a standard box.

Top side has in and out 1/4" jacks plus 48vdc input. Top has a standard stomp switch, and 4 pots; gain, overdrive, distortion and tone (sort of).

All stainless, including the four stainless screws holding it together. Like I said, top notch, but at their price point you should expect that.

Inside are the two boards. One (the main one) with a few discreet parts and several micro board mount parts, I assume various resistors and caps. There are two 1/4w resistors, two diodes (germanium 1N I think, can't read, but the little orange-black in glass kind). A 330uf electrolytic and 3  ICs (op-amps?):

BB-OPA
2604AU
84VFX

The second board is held by the footswitch, and is connected to the first by a ribbon cable (pretty neat space saver). It has 8 LEDs in two rows of 4, two red and two yellow, which apparently are used for distortion. They fluctuate depending on the signal strength (guitar volume and OD setting). A third LED is a three-legger, it appears to show a dim light when plugged in and a stronger light when the switch is on. I like that approach too. This board has the mystery component. A flat potted box with 5 legs coming out. The wide flat kind, like on a power triode or something. And it has an IC:

BB-OPA
2604AU
89N67

That is it. It works well for me. The 48V inline brick supply is to my liking but it might be a pain with a full board. It has plenty of clean gain and sounds good on bass. The distortion I'm not really into but that is where the tone knob comes in; it appears to pull the rough high freqs out of the distortion, muddying it a little and making it a little more pleasing to my ears, but I prefer to use it just as an overdrive to pump up the amp input. I'm not a musician/technician but i did stay at a holiday inn express while playing one on TV. YMMV. 



slacker


ScottB

Nice. That would explain the very clean operation i guess.


ScottB

Quote from: Johan on January 17, 2011, 03:48:13 PM
Quote from: ScottB on January 17, 2011, 03:00:31 PM
There are two flavors of mystery meat in this taco, one is a 6-pin IC which appears to have had the silk screen removed and marked for orientation, plus the potted portion which is 5 leads and reminded me of a bucket brigade, which is what got my imagination rolling.

I know there are a few opto-ic's like that...a led on one side and usualy a BJT with an optical base on the other. but sometimes they have a FET with optical gate. perhaps this device is related to the old "Expandora"? wich used such ic for pick attack sencitivity...
J

The IC I ID'd after getting some light on the subject.

But the potted thing, imagine the flat wide legs on say an SCR. Now imagine 5 of them side by side. That is what is coming out of it.

I put it all back together for now, as i want to play with it some more. And I may have to find a better camara and go back in, these are somewhat disappointing.

caress

Quote from: ScottB on January 17, 2011, 12:46:22 PM
Really there are plenty of people still using tubes today to surf the net, right? That is kind of pat answer discussion i wanted to avoid; as far as it being marketing hype, oh yes indeed, but entirely bullsh*t? No, because this is exactly what a lot of bucket brigade delays are doing. Tubes never lent themselves to high speed boolean function (but they were present in the large drum drives, i don't know why). Bucket brigades were the way to build a "discreet component" microprocessor.

Which is the intriguing part. It is a pretty nice little pedal in my (non-musically proficient) opinion. Should I go scrounging magnavox chroma delays out of old TVs? Ha!

i'm not saying that their claim isn't true.  yes - if you're using silicon transistors or BBDs or whatever random parts an "old analog computer" used, then you're using analog computer technology - great.  what does that mean for the pedal?  nothing.  it's a bullshit claim in that it means nothing.

why don't you post some of your pics?  maybe someone can help you de-mystify those odd components.

ScottB

I'll agree with that.

You know I wonder if the potted part is something as simple as say an LM675 or some other op-amp, in conjunction with the diode array and a clean amplifier.

What the heck, here goes the PB album:

http://s593.photobucket.com/albums/tt16/Caspar98/Holy%20Fire%20guts/

here's the box intact with cover off, the little black box is the mystery part:








Jhouse

It looks a lot simpler that I thought it would be. Oh how I loathe SMD parts though.

ScottB

Sorry to do this to you all, but moved to the members forum. Same great service but with cold beer on tap.

Mods, please feel free to delete this thread entirely, i rehashed and consolidated it in the other forum as advised. Sorry to cause extra work.