freestompboxes.org

It started out as an incredible story, fromDIY rags to boutique riches.

But somewhere along the long somebody forgot to delete a link, well, not really, seems like a community effort after all... no?

Cream Pie and Fet stage with tone control:


mac

which is here

This is the Cream Pie version I'm building soon:



The texture pot adds some amount o fnice dirt but reduces the final volume at min.

mac

which is here

Meanwhile, on the other side, shit starts hitting the fan when the first boxes are delivered:

QUOTE (jasonfuzz @ Jan 22 2007, 05:12 PM)
So I got mine in the mail today but there seems to be a problem with mine. The tone knob doesn't do anything.

I found the same thing with mine. Tone knob does very little if anything at all. Is that normal?

The Tone knob is subtle, but should be working. We've had a couple of people say the same thing. I just called Andy. We will get the issue resolved before I go into full production. Anyone who has one w/ a tone control that isn't working can send it back and I'll remiburse their shipping cost to get it back to me. I'll either get it fixed for you guys or send you one from the second batch after they've been thoroughly tested. I've been taking on too much, and I rushed the first batch out. This is my fault, so I apologize guys. This isn't the way things normally work for us, and I hope you all know that. Again, I'm very sorry for any inconvenience.

http://z6.invisionfree.com/Tone_Factor/ ... =573&st=90

There it ends, somewhere last January... Btw didn't reread the whole thread but the problem with the tone control is already mentioned there... if it's the same.

Re: When did it become "bad" to post schematics? on: 04-05-2007, 14:13:55
Just a quick 2 cents....

I used to LOVE sharing with the forum....

Then came a time..the last few months, for instance...where i have been licensing designs in order to helps me make a living (FYI...I have eaten Ramen Noodles and Tortillas for the last 2 months, and little else due to finances....but money from the licensing is starting to come in now) ....and then find somebody selling (or underselling) you using your circuit. I'm eating Ramen Noodles, this guy is stealing potential revenue from me.

And I'm not trying to be "punchy" here, but this "anointed / holier than thou" name slinging is bullshit. I , as well as many others, have participated in this forum, freely helping when i can, and generally tried to promote the hobby. Having somebody say that anyone who pulls his schematics thinks he is "better than the rest of the forum", well that pisses me off

I wonder what kind of licensing deal it was that improve his standard of living. All the while Tonefactor could have just used the online schematic and renamed it. Why didn't they do that? Just to cash in on the promotion and noise made about this box at diystompboxes.com.... So amateur diy-ers are given money just to pull their schematics.

On a further level, Tonefactor is making money off the forum's reputation without given any compensation to the forum. See how deep this goes?

zj

i'll have more to say later, an interesting letter....

so I had an honest question about that licensing deal for Tonefactor, so I just mailed the guy:

Dear Sir,

I really have an honest question which has been bugging me for a while.
How do the licensing deals really work? Are you really paying hard cash to the people who developed the pedals? None of that stuff, I believe, is or can be copyrighted or patented or protected otherwise.

I'm specifically talking about fx that were published online before the deal with Tonefactor and are still (with or without your knowledge) floating on the internet. In that case, exclusively can never be guaranteed.

I suppose a healthy business cannot afford paying more money than it legally is obliged to.

thanks for your time,

And an nice and honest reply, but not to every question. Which is ok, of course. But interesting nevertheless:

Hi,

Thanks for your concern. I don't discuss the details of our licensing.
Just for the record, though, most of our products aren't licensed.
They're developed by our own contracted builders, or products are
commissioned by me. If you're talking about the Cream Pie, it's the only one that has really been publicized online, but our version isn't just
like the one that is floating around, so no need to worry.

Also, I feel like I should mention that a big part of what the consumer
pays for is the assurance that they're getting a product from a
legitimate, reputable company. There is no protection circuit-wise,
however as long as we keep up the quality control and customer service
I'm sure we will be fine. Thanks again,

One thing isn't true, however, the Tonefactor Ultralord is in fact the Dirty Sanchez. Just trying to find that thread over there but the server is so slow...

First the samples: Fender Strat + booster into BF Super Reverb

Download Germaniac Clean
Download Germaniac biased at 3_5V
Download Germaniac biased at 4_8V
Download germaniacbiased at 6V

Here the schematic, without a simple volume control I did add after it to be able to max out gain.



Q1 is a low leakage Germanium NPN, I used 2SD352H with gain of hFE 115.

C1 is the input capacitor -- .022uF or 22nF would be a good starting point, but you can try values up to .1uF
C2 is the output cap - .047uF or 47n for starters, but try up to .1uF (100nF)
C3 is 47uF or higher for more extreme though less defined maximum gain. Connect the negative side to the ground.

R1 is the bias resistor, a 100k trimpot that regulated the voltage fed into the transistors collector. Use the variable resistor to put about 4.5V on the collector
R2 is the gain control, a 5k B potentiometer in series with C3 a electrolyte cap 47uF to ground.

To sum it up, put your guitar signal into the base through an input cap, connect collector through a biasing resistor to your 9V, connect the emitter to ground through an electrolyte and take the output signal from the collector after an output cap.

Can you re-introduce the missing layouts too?

I don't like the collector resistor being a pot and I don't like the bias setup.

How do you design for the collector current if you change the collector resistor value as a pot?

Why do people use drain and collector trim pots? You saw it on the web? Not good design IMO for a REPEATABLE build. Trim pots can mean you did not do it right. Yes I have bias trims in some schematics but I wanted an external control and they are not in the collector leg.


If you are going to design like this maybe getting an ohmranger and switch in resistors or use a big pot with clips and measure the resistance that works then make up a parallel/series set of resistors of the right value

Now different things can change the clipping so it is hard to tell what the person had in mind when 'designing" it. I do see the feedback path from collector to base but look at the gain setting by the 3.3meg and series input source vs the openloop gain of the Ge transistor

You can design a bias network to "force" the transistor to bias where you what it: however the input R might be too low but then you might be able to bootstrap it to raise the input R.

Maybe this was part of the sound design but from just reading the web it is hard to tell

How will the bias and tone shift on a stage on a sunny hot day outside?

don't have to sim, measure

Take temp measurements and voltages readings maybe place the effect in the frig take the data, room temp 70F, hot sun for an hour also a fast sound test ateach temp.

gus wrote:I don't like the collector resistor being a pot and I don't like the bias setup.

How do you design for the collector current if you change the collector resistor value as a pot?

Why do people use drain and collector trim pots? You saw it on the web? Not good design IMO for a REPEATABLE build. Trim pots can mean you did not do it right.

I absolutely agree with you 100% - though in the case of Modman's simple booster, I believe the trimpots are there for sake of experimentation. I don't know why they are there in the Cream Pie.

Most people seem to be tacking trimpots into circuits to compensate for variations in different transistors, but I don't see why they don't just design a "correct" circuit as you said, so it doesn't require adjustment to work correctly.
IMO, the worst offenses come when people are trying to emulate a specific tube amplifier by using JFETs and they have trimmers on every Drain to adjust current. What's worse is when the design has instructions to adjust every JFET for "4.5v on the Drain", even when there are clearly different values of Source resistors at the different stages - therefore the idea of using different Source resistors to optimize bias for each stage is completely lost because they've all been adjusted to be as if they had identical Source resistors.

I would really like to know what sort of biasing arrangement you'd suggest for these simple BJT circuits. I've come up with circuits that work well for what I've been doing, but I'd like to see how my ideas compare up against others.

Thanks for confronting this issue Gus! I'm sure this is the only forum where we could dare have this conversation.

Thanks so much for replying Gus and Soulsonic,

I think I need to give a little background here. I got really interested in boosters, and wanted to see that GE booster that was around. However most of the links were dead. When somebody sent me the schematic I couldn't understand that it would be so simple.

There might be a bit of a confusion. I made sample clips with different baising because I didn't know how to bias it. At 7.5V like rangemaster or 4.5V. It's not meant to be a function of the stompbox. it's a trimpot indeed, like soulsonic said.

Does any of the clips sound interesting to you?

All depends on how much grit you want in the sound. Was definitely looking into a tone control for this circuit but got side tracked.

I posted this changed Creampie as an entry for the FX Competetion and it won. But no one cared to comment on the functioning of the circuit, which was the only reason I posted it. It's also very low component count on purpose.

I did omit a large 3,.3M base-collector resitor because I thought it didn't make a difference (in sound).

But please, gus show me how you would set up a one stage GE booster.

When they first appeared this was the original schematic
.

.
.
Then the pot was moved and this schematic was issued
.

.
Then there was a real argument, Andy got his "deal" and the schems were pulled.

I never got that one... whats the big deal? GE version of the Electra distortion, less the clipping diodes. Why waste a perfectly good GE on a booster? Nothing against Andrew, more power to him! IMHO he has posted much more interesting stuff than that.

I wish these forums had a scratching head smiley

phh....3M3 from base to colllector with a Ge-transistor..

I don´t know what the circuit should do, but I think it will be a little bit noisy with a low collector current.

For a (non-distorting) booster a "normal" design would be:
1.) choose the supply voltage (e.g 9V)
2.) choose the collector current (e.g. 340µA)
3.) place the quiescent-collector voltage above the middle of the supply voltage. (e.g. 6V, gives a collector resistor of 10k)
4.) choose the emittter resistor that there is approx. a tenth of the supply or 1V (gives 3k3)
5.) look for the hfe /ß (e.g. 100)
6.) divide the collector current through the hfe (gives 3,4 µA)
7.) mutiply this value by 10 (e.g. 34µA)
8.) place a voltage divider at the base with the caculated crosscurrent (of 34µA) so that the base is biased at the voltage at the emitter resistor (1V) plus the base-emitter voltage (Ge: 0,2 V Si: 0,65V) (is 1,2 V)
9.) so we will get a total resistance for the voltage divider at the base of 265k. For 1,2V we would need 35k from base to ground, let´s take 33k and 220k for the resistor from plus to the base. This will give 253k in total and produce a cross-current of 35,5 µA achieving a voltage of 1.17V at the base.
10.) The emitter resistor is only there to produce a current feedback to stabilize the circuit against temperature changes. For most AC-gain place a bypass cap of 25µF across the emitter resistor.
11.) The base voltage divider contibutes much to the (low) input-impedance. The collector resistor determines the collector current.
So the best way to adjust the circuit is to change the emitter resistor or to make it adjustable. (1k5 resistor in series with a 2k5 poti).
12.) That´s it.

analogguru

analogguru wrote: 2.) choose the collector current (e.g. 340µA)
analogguru

On the basis of what do you choose the collector current? Optimum for the transistor used? Thanks still for spelling this out AG, will look into this with this info once more.

RLBJR65 wrote:I wish these forums had a scratching head smiley

you wish, but just click 'view more emoticons'


still unanimated, I know, will do better soon, but this is a bit low on priority list

On the basis of what do you choose the collector current? Optimum for the transistor used?

After I finished to write my post I awaited this question. But then I was too lazy to edit it.

1.) Input impedance:
If "higher" input impedance is required, lower the collector current or use higher hfe/ß.

2.) Noise characteristics:
If low noise is required look at the data sheet for the noise figure dependent on the collector current drawing for the best collector current for the lowest noise.

3.) power consumtion:
lower collector current = lower power consumtion = longer battery life

4.) Output load:
in very short: the output load should never be lower than the collector resistor.

All this parameters have to be considered by designing an amplifier-stage and influence the collector current decision.

analogguru

AG, thanks for that great explanation!

D'oh! Guess I never paid that much attention to them

Yeah, there's gotta be a way to make this thing sound better. I tried building it twice and still couldn't see what the uproar was all about. Hats off to Dragonfly for making money off this crap!!!!!
For simple germanium booster/overdriver type things Pete Moore's "Range Pig" blows this one away. Do yourselves a favor and build that instead.

To me the CP looks like a stripped down COT 50.

It seems that the Cream Pie was designed for a Si-trannie and I think that any common Si-trannie like a BC109A will work in this circuit. Also, I would bias it to app 5V like a Rangemaster.

JHS

greenskull wrote:Yeah, there's gotta be a way to make this thing sound better. I tried building it twice and still couldn't see what the uproar was all about. Hats off to Dragonfly for making money off this crap!!!!!

I have to say, I was one of the supporters of the Creampie, I thought it sounded pretty darn good with the CV7112's that Aron was selling at the time.
I think I ended up with mine at 5.5V......still haven't boxed it up 'cause after he pulled the schems down, I came up with my own Ge full booster built around the Rangemaster circuit and thought it sounded a bit better.
Besides, then it was "mine"!

markm wrote:

greenskull wrote:Yeah, there's gotta be a way to make this thing sound better. I tried building it twice and still couldn't see what the uproar was all about. Hats off to Dragonfly for making money off this crap!!!!!

I have to say, I was one of the supporters of the Creampie, I thought it sounded pretty darn good with the CV7112's that Aron was selling at the time.
I think I ended up with mine at 5.5V......still haven't boxed it up 'cause after he pulled the schems down, I came up with my own Ge full booster built around the Rangemaster circuit and thought it sounded a bit better.
Besides, then it was "mine"!

Yeah you were!! That's one of the reasons I tried it a second time. Gotta try the one you came up with next and that Soulsonic LPB-1 with the germ inline at the output next to see if they hit the spot.

For fun take the The NPN boost

Drop a NPN Ge in it should work. If you have PNPs reverse the caps and make it a + ground circuit

It is a circuit that has a stable bias and increased input Z and an input interaction with the gain. The values were kind of set by the parts at Radio Shack(USA) when they sold parts so a person could buy the parts at RS.

Hey Gus, I've built your NPN boost.
Handy circiut. I have been meaning to try it Ge some time. I've heard of people having great results with it.

gus wrote:For fun take the The NPN boost

Drop a NPN Ge in it should work. If you have PNPs reverse the caps and make it a + ground circuit

It is a circuit that has a stable bias and increased input Z and an input interaction with the gain. The values were kind of set by the parts at Radio Shack(USA) when they sold parts so a person could buy the parts at RS.

Ya know, I think I did this at some point but never quite got around to solving some of the bias issues.
Certainly worth re-investigating though.