Fulltone Ultimate Octave

[LucifersTrip]

I found a thread here dealing with the Ult Oct and Tone Machine that has the schematic:

http://www.diystompboxes.com/smfforum/index.php?topic=82223.msg682384

[swt]

i have one of the early 90s uo, and it has bc108c trannies, 50k pots, .015 for the mid scoop part of the tone control, and switching between .047 and .001 tone caps. In my opinion, it sounds better than the newer ones with 2sc828 and 100k pots.

[jmasciswannabe]

i have one of the early 90s uo, and it has bc108c trannies, 50k pots, .015 for the mid scoop part of the tone control, and switching between .047 and .001 tone caps. In my opinion, it sounds better than the newer ones with 2sc828 and 100k pots.

Do you all think that the values for r3 and r4 (in schematic above) would be different as well since the caps in the tone section would be changed. Any ideas? Thanks!

[jmasciswannabe]

Any ideas...anybody?

[El Heisenberg]

Thats the fulltone schem. All fulltones pedals are just other brands pedals. Amz boost is fat boost. Foxx tone machine is ultimate octave. Tychobrae octavia is fulltone octavia, voodoolabs overdrive is obsessive compulsie drive (OCD). What else is rippes off from other designs? Not even ripped off just totally cloned.

[MmmPedals]

Full drive is a tube screamer

[liquids]

Any ideas...anybody?

Seriously, I chant this mantra to the point of people's nausea, but breadboard it, and see what you yourself prefer, by ear!  And/or check the Foxx Tone Machine / Superfuzz schems and see that variant too...and / or spice simulate the tone stack to get a visual of the changes/expiriments.   It's a simple T-type filter, and worth the investment to learn it and understand it.  It's a common fuzz/octave tone stack, and there are lots of variations on the theme that work well, depending on what your ears want and like to hear.

[jmasciswannabe]

I knew that this is a clone of a FTM, as I ran across it when I set out to build another octave fuzz. I've already got a superfuzz which if I were to build again would go with the zvex clone as he made the volume and tone improvements that I would have liked to have on mine.

I have already completed and populated the board with the values described above using the same resistors. My inquiry was based solely on saving the hassle of having to pry parts out once boxed up. I absolutely hate that, especially since it is on perf. Thankfully, SWT responded to a pm and said the resistors were the same. So no worries.

[El Heisenberg]

So i've decided to build another of these. My first idea was a Tychobrae Octavia and Fulltone Ult Octave together in a box with a DPDT to toggle between the two. Dual gang pots. I'd have to bring a 500k pot down to 50k tho... so I decided to just stick the Ultimate Octave in.

I haven't started. I got the 2SC828 trannies and they have weird pinouts so It'll be a little new trying to perf the thing.

Are the electrolytic caps C7, C8 and C9 oriented properly in the schematic?

I used all tant caps for the 10ufs in my last biuld. Maybe should try normal electrolytic. 

[El Heisenberg]

Jeez I can't beleive how much of a difference 2SC828 transistors had on the sound. You definetly should use these transtors.

[azrael]

Did you measure the hFe? I would guess that is what is making the difference from the other transistors...

[liquids]

That and the lower input impedance of the transistors.

[El Heisenberg]

EH I can't measure HFE, the multimeter I have is crap. I can stick the leads in teh holes but it's like they don't clamp in or somethig and I just get weird random readings jumping all over the place. Been meaning to build a slow gear, but been holding off till I can match some transistors.


But yea, this pedal sounds way different than the one I built before. I used pretty low HFE transistors for that pedal too. I used all tant caps for the coupling caps but there are less highs in this one where I used electrolytics. There's alot less gain too.

[El Heisenberg]

i have one of the early 90s uo, and it has bc108c trannies, 50k pots, .015 for the mid scoop part of the tone control, and switching between .047 and .001 tone caps. In my opinion, it sounds better than the newer ones with 2sc828 and 100k pots.

This must be the one used by Josh Homme. I never wanted to say so, but the Ultimate Octave I had before didn't sound anything like what I heard on Little Sister! I did better with a Green Ringer and a Big Muff. But after changing the mid scoop cap to .015 the mids are back and it sounds just like the record! Finally! The octave up doesn't sound thin and sharp, it sounds round and loud and thick and you can darken it up.

Gunna add a switch to switch that cap between .015 mf and .1 mf. Along with a switch between .001 and (?) for the highs. And another switch to switch the tone control diodes to two 1N4001s.  

50k pots work way better for the fuzz and tone controls. 100k for the volume. The 10k resistor in series with the fuzz pot does have an effect on the sound. Try and play the little sister solo.

I'm really glad I revisited this pedal. The first one was nice but didn;t sound like Josh Homme at all. Heck the reason I went out and got the 2SC828 transistors was cos I thouht those alone would gimme that tone. Had to have both. Lo gain trannies and the mid cap change,

[Derringer]

glad to hear yu got your pedal dialed in man

Do you know if Homme use the non-octave setting for his rhythm sound? I always thought his distorted rhythm was from his amp.

[liquids]

I find the fuzz pot wires as the standard voltage divider is pretty useless in this circuit.   I prefer making it just series resistance - more like a texture control that also has some affect on gain... likewise it's useful to have series resistance at the input.  But that's probably not at all how Josh Homme has his. 

[El Heisenberg]

glad to hear yu got your pedal dialed in man

Do you know if Homme use the non-octave setting for his rhythm sound? I always thought his distorted rhythm was from his amp.

I dunno. I think his sound is from his amp too, and his MPF-1, but the octave on this pedal sounds great without the big scoop.

I dunno why Fulltone would change the FTM and then go BACK to something more similar later. Especially cos the new version sounds like crap compared to the old one.

To be honest I never liked the sound of this pedal before. It was like an ugly sounding big muff with less mids. But now with the mids back i can really get some use out of it. EVERYONE should build this version! Especially if you were disgusted with the first one!

[Derringer]

cool

glad i read this man ... I built one using GGG's layout and modded it to UO specs about a month ago and thought it was just 'ok'
I have a big muff and a superfuzz and this sounded a bit like a cross between the two. I totally understand what you meant when you likened it to a BM.

this morning I switched the 0.1uf scoop cap for 0.015 and now it sounds a lot better in both (oct /non-oct) modes
right now I'm using it primarily for just the non-oct fuzz and have my Superfuzz ahead of it if I need an octave boost

[sansaat]

Has anyone built the ultimate octave using the bc108c trannies that were used in the older pedals? As far as the datasheets go they are pretty high gain, around 800 or so, not anywhere near to the 2sc828.

[jpiddy118]

since it's already been resurrected, when ya'll say "scoop cap", which cap are you referring to? I'm confused... modded my FTM clone to UO specs per El Heisenberg's posts, but now I notice they were posted before this thread came about. I haven't been thrilled with my clone either, it's very BMP and not quite QOTSA, even with UO mods.