Catalinbread - CB30  [traced]

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mmolteratx
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Post by mmolteratx »

kbibs wrote:I have a question fr anyone that has one of these. With the gain turned down all the way, where about on the volume knob do you get unity volume? ... with my breadboard build and a few different cap values I'm about at max volume before unity. Is this about right?
Yup. The volume needs to be about maxed for me with the gain all the way down. It's below unity with my Suhr's high output bridge no matter what.
roseblood11 wrote:The drive pot and the last transistor stage are different as well.

I still doubt that the marked parts are correct. The cap from input to ground is most likely 220pF.
But there are too many things unclear. I think we need better pictures or a look at a different pedal.

@mmolteratx:
- Could you please recheck the parts values (at least those of the marked parts) and maybe post the codes on the caps?
- Are the connections around the 330pF cap really correct?
- Is the cap from output to gnd really 10nF?
The 22n cap highlighted is a Panasonic labeled 223 so that's definitely 22n. The 10n is a yellow one marked .001k on one line and 100k on the next, these I'm not sure about at all and the 2n2 one to ground at input is one of these. The 470k resistor is yellow-violet-yellow-gold and it's the big carbon comp. The 330p cap is a blue multilayer ceramic marked 331. The cap from output to ground is a Panasonic labeled 103 so that's definitely 10n.

The 2n2 at the input is labeled .0022k on one line and 100k on the next. The source cap off of what's labeled Q3 in the schem should be 22uF.

The styrene caps are the 100pF cap across the gain pot and the 470p to V+. One lead of the 470p goes to the 22uF/680nF filter caps and the other goes to the + lead of the 220n electro and the source of what's labeled Q4 on the schematic. :hmmm: It's labeled 470J.

The 390R source resistors are orange-white-brown-gold.

If the .001k is actually a 100pF and the -0022k is actually a 220pF, the values make perfect sense. :hmmm: I dunno as I've never used these types of caps before. They look like Nichicon films with different codes.

I'll get some pics when the light is better tomorrow and after I manage to finish a paper and get some Calc done.

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roseblood11
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Post by roseblood11 »

if 0.0022 is 2n2, then 0.001 should be 1n, not 10n ;-)

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Post by mmolteratx »

roseblood11 wrote:if 0.0022 is 2n2, then 0.001 should be 1n, not 10n ;-)
Ya, I think I rushed the schem and had some typos that weren't there on my original handdrawn schem. I'm gonna redraw it based on that in Eagle tomorrow and post the project file for anyone who wants to tackle a PCB layout.

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Post by bajaman »

right :thumbsup
so the 10n should be as suspected 1n and the bypass cap on the second gain stage should be 22uf NOT 2.2uf.
A bit gutless gain wise though - perhaps would function best if last in the signal chain :hmmm:
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Post by mmolteratx »

bajaman wrote:right :thumbsup
so the 10n should be as suspected 1n and the bypass cap on the second gain stage should be 22uf NOT 2.2uf.
A bit gutless gain wise though - perhaps would function best if last in the signal chain :hmmm:
bajaman
Yup. It doesn't have a ton of gain or much "punch" like the DLS. The most distortion I can get out of it is Brian May type stuff when the gain is cranked and I'm slamming my strings.

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Post by roseblood11 »

Maybe this pedal is just a joke? "Wampler builds a 'Cranked AC', so let's build a 'Lame AC'..." :mrgreen:

Even in the demos the pedal sounds much better with the Naga Viper booster in front of it.
I'll build it in a BB-enclosure together with a compressor in front of it, that can boost the signal a bit. Maybe mictesters compression sustainer.

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Post by kbibs »

Thanks mmolteratx for the clarifications, they all make sense! ... that 2n2 on the input still loads down my tele if I don't have a buffer or other pedal driving it.

I wonder how much of a difference all the different capacitor types (electro, polystyrene, film, ceramic) make in the sound of this pedal? ... or even the one big carbon comp resistor! :lol:

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Post by mmolteratx »

roseblood11 wrote:Maybe this pedal is just a joke? "Wampler builds a 'Cranked AC', so let's build a 'Lame AC'..." :mrgreen:

Even in the demos the pedal sounds much better with the Naga Viper booster in front of it.
I'll build it in a BB-enclosure together with a compressor in front of it, that can boost the signal a bit. Maybe mictesters compression sustainer.
Ya, it has a kind of AC30 vibe but doesn't sound nearly as good as the WIIO and DLS I've owned. It's kind nasally no matter how I set it with my gear. I've gotta turn the treble and cut knob on my amp way up and then the clean sounds like ass. I'll probably sell it once I snap some more pics.

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Post by roseblood11 »

A treble and a cut knob? Do you have a real Vox? In that case you have two identical tonestacks in series, that would explain why the CB-30 doesn´t sound good with your amp.

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Post by mmolteratx »

roseblood11 wrote:A treble and a cut knob? Do you have a real Vox? In that case you have two identical tonestacks in series, that would explain why the CB-30 doesn´t sound good with your amp.
No, it's a THD Flexi 50. It's similar to a Trainwreck Express with a grid leak biased input stage, passive Baxandall tone stack with mid knob and a Vox style cut knob.

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Post by bajaman »

on reflection - I suspect that this pedal was designed for direct to computer recording - definitely no good as a distortion box in front of a tube amplifier :wink: :lol:
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Post by roseblood11 »

They use an amp in all of their demo videos...

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Post by mmolteratx »

Here's a bunch of new pics. There are some duplicates because I was having trouble with Photobucket. :lol: https://s378.photobucket.com/albums/oo2 ... 1QQtppZZ20

Here are the cap values labeled.

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Image

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Post by mmolteratx »

Also, here's a clip of me futzing around with it. http://dl.dropbox.com/u/8021347/CB30.mp3

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Post by mmolteratx »

Here's the redrawn Eagle schem with the updated values I promised. One's a PNG, one's the Eagle project file for those who want to do a board layout. I used Madbean's library for all the parts.
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CB30.sch
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CB30schem.png

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Post by ShortScaleMike »

OK, updated with the 10nF->1nF and 2.2uF to 22uF changes.

Is anything else needed?
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Post by mmolteratx »

I think that's good. I don't really have time to look over it in detail right now but maybe later tonight or tomorrow I can look it over and I think I have most if not all of the parts needed to build a clone so I'll try to build it up this weekend.

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Post by roseblood11 »

Have you tried a 18V power supply? Is there a huge improvement soundwise? I'm still not sure if I should include a voltage doubler in my build...

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Post by mmolteratx »

I've tried 12V but not 18V. There's considerably more output and headroom and that's about it. I don't have an 18V supply or else I'd try it right now. I'll see if I can find the 18V cable for my PP2+ or if I have enough spare ends to make one.

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Post by ShortScaleMike »

Can we mod this puppy simply to goose more gain out of the Mu Stages?

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