Oddfelow Effects - Caveman Overdrive

jreeves47 · Post by **jreeves47** » 13 Mar 2014, 23:09

flavor of the month at the polishers forum
pic from ebay

jubal81 · Post by **jubal81** » 13 Mar 2014, 23:28

Funny. Id've sworn from listening to the demos that it would have been 4049-based.

FiveseveN · Post by **FiveseveN** » 14 Mar 2014, 00:36

Maybe it's a 4049 cut in half!

No close-up yet?

Lawnchair · Post by **Lawnchair** » 24 Mar 2014, 17:25

The descriptions posted on TGP remind me of the CJOD. No idea of the topology.

gtrplaya101 · Post by **gtrplaya101** » 12 Apr 2014, 02:56

Heres another close up: (Photo not mine)

I'm seeing tl072??
single clipping diode
dual transistors
humm

mmolteratx · Post by **mmolteratx** » 12 Apr 2014, 03:54

FET clipping in the feedback loop. It's a boring op amp clipper with basic frequency shaping. Maybe Zen Drive ish. Not worth tracing, IMO.

Manfred · Post by **Manfred** » 12 Apr 2014, 05:15

mmolteratx wrote:FET clipping in the feedback loop. It's a boring op amp clipper with basic frequency shaping. Maybe Zen Drive ish. Not worth tracing, IMO.

I agree with you.

DrBoogey · Post by **DrBoogey** » 19 Jun 2014, 13:12

Hi guys

I looked inside one and I saw two 2N7000 and one TL082, that reminds me of something

Drive

Cheers

mirosol · Post by **mirosol** » 19 Jun 2014, 14:56

Manfred wrote:
mmolteratx wrote:FET clipping in the feedback loop. It's a boring op amp clipper with basic frequency shaping. Maybe Zen Drive ish. Not worth tracing, IMO.
I agree with you.

Nothing is not worth tracing. In fact, more of a ripoff, more important that it is traced.
+m

DrBoogey · Post by **DrBoogey** » 20 Jun 2014, 06:20

I traced a unit from a collegue and my guess was right, its a slightly modded Fulltone OCD
I have drawn the changes in the OCD schematic I found in the net
The Diode is not a 1N34 or other germanium, maybe a shottky diode
I breadboarded the circuit and compared with the original unit, it sounds absolutly the same as the original Caveman Drive (differences: I used a TL072 and a BAT85 for the diode)

Cheers

mirosol · Post by **mirosol** » 20 Jun 2014, 09:05

This is exactly what meant with my comment above. I think it's important that we uncover blatant ripoffs that result in disinformation and well, crap like this:
http://ztalk.proboards.com/thread/60746 ... -overdrive

Quote: "This sounds like an awesome pedal. And, also sounds like an original design. I wonder if this pedal will achieve the same street cred as the Timmy. I'm hoping yes - because I love the idea of people coming up with original designs and becoming successful with them. The question is . . . how long will the $132 price tag last?"

No. I don't want to see anyone becoming successful with changing couple of resistor and cap values in existing design. Seems like the price tag got a bit questionable a few moments ago, when DrBoogey posted his trace.
+m

IvIark · Post by **IvIark** » 20 Jun 2014, 10:15

DrBoogey wrote:I traced a unit from a collegue and my guess was right, its a slightly modded Fulltone OCD
I have drawn the changes in the OCD schematic I found in the net
The Diode is not a 1N34 or other germanium, maybe a shottky diode
I breadboarded the circuit and compared with the original unit, it sounds absolutly the same as the original Caveman Drive (differences: I used a TL072 and a BAT85 for the diode)

Cool. How is the Boost switch wired in the original? I can see in the gutshots that two poles are used but by the schematic you could obviously do that with one pole.

mirosol · Post by **mirosol** » 20 Jun 2014, 10:17

I believe the other pole is for the "Boost" indicator LED.

IvIark · Post by **IvIark** » 20 Jun 2014, 10:33

mirosol wrote:I believe the other pole is for the "Boost" indicator LED.

Ha ha, aah right, I didn't realise it has an indicator. Should have been bloody obvious really

DrBoogey · Post by **DrBoogey** » 20 Jun 2014, 12:06

IvIark wrote:
mirosol wrote:I believe the other pole is for the "Boost" indicator LED.
Ha ha, aah right, I didn't realise it has an indicator. Should have been bloody obvious really

Yes, its the LED indicator

IvIark · Post by **IvIark** » 20 Jun 2014, 13:03

This should cover it

mmolteratx · Post by **mmolteratx** » 20 Jun 2014, 19:37

Here's a redraw of the schem with a slightly less retarded boost control. Might do up a PCB later today.

mmolteratx · Post by **mmolteratx** » 21 Jun 2014, 00:14

Did this pretty quick, but I looked over it and it looks good, as long as the schematic is good. Uploaded to OSH Park. I don't guarantee that it works, but it's very likely that it does. Might be up to organize a group buy after it's verified and if there's enough interest. Will fit in a 125B for sure with battery and everything. Might even fit in a 1590B with a bit of ingenuity. Plus it doesn't look like a monkey designed it.

https://oshpark.com/shared_projects/uhVgxqEH

mmolteratx · Post by **mmolteratx** » 11 Jul 2014, 22:14

PCB above is verified.

zedsnotdead · Post by **zedsnotdead** » 06 Jul 2015, 00:09

Hi guys, sorry for the necro-post.

I built this thing some days ago, and I'd like to share with you some thoughts.

Here it is, built on mmolteratx OSHpark PCB (excelent work, thanks a lot!

there's only just one thing - please check note @ end of post):

Now a few notes regarding the sound.
1- I compared it vs OCD. Caveman seem a little darker sounding, but tweaking the tone control they sound almost identical.
2- I used a B100K pot for boost control. Only at around 80% CW you start to notice a "boost on/off" difference. Lower than that rotation it doesn't do much for boosting the signal. What I mean is if you have the boost pot @ 50% and step on the "boost" footswitch you will hear almost no difference in volume. You only get it significantly above 80%.

So what I was wondering is:
a) how do I make it less dark sounding? Should I change the tone cap? Should I change the pF cap on the feedback? Both??
b) do you think that using a B50K pot for boost control could give a better "range spread" for it?

Thanks!!

@mmolteratx
Boost pot/trimmer connections are backward. 1 is 3, and vice versa

Oddfelow Effects - Caveman Overdrive [traced]