New at runoffgroove.com: 22/7

[tol]

In EPFM Anderton talks about the lower noise in the Tube Sound Fuzz when compared to germanium fuzzes. I've always liked the Red Llama/Tube Sound Fuzz but have noticed noise. So I didn't quite understand his statement. I might try to make the 4049 to 4069 adapter 2nite and see if it makes a difference. I'm still thinking those 2 150pf caps in the clipping stages could be raised since a typical muff has 470-560pf. I'm gonna try when I get home from work. Tempted to go home sick. I hate my job.

[John Lyons]

The 150 cap I assume was chosen to go with the other values to match the big muff tone.
The 22/7 sounds about right tonally compared to a BM. Making the 150p caps 470ish will kill a
lot of the high end making it too dull I believe. Less hiss though 
The Llama has a lot less going on. With all the fuzz and stages going on in the 22/7 I think
that it just might be the nature of the beast.
The Emma Reezafratitz (sp?) uses the same chip and it quiet though...
I'll have to check that schematic.

John

[azrael]

Let us know if the 4069 is tonally different from the 4049. I have a steady supply of 4069's in my EE lab, so I'd like to us some of those.

[Brymus]

OK guys here's my way of removing noise from CMOS builds.
Add a 10-22n at the V+ of the IC (right at the pin)this will remove squeal when the voltage drops as the battery loses charge.
I culled this from the data sheet,now I can run the chip down to 5V w/o any squeals.
And a 10n shunted to ground at the input before the coupling cap,this will get rid of the hiss in the 3LD/WHRL- should work here too.

[John Lyons]

OK guys here's my way of removing noise from CMOS builds.
Add a 10-22n at the V+ of the IC

From V+ to ground correct?

EDIT:
Putting the cap from the input to ground will help with possible oscillation and external noise
at the input but the noise I have is in the circuit somewhere not coming in through the input.
With the guitar vol rolled off the noise is still there.
I audio probed it and it starts after the first clipping stage (no surprise) and gets much louder
after the second clipping stage (no surprise).
The thing is that it's not just his but goes lower into the mid and lower frequencies.
I think it's a by product of the IC and this circuit.
Brian Tremblay, STM where are you? 

JOhn

[tol]

In EPFM Anderton talks about the lower noise in the Tube Sound Fuzz when compared to germanium fuzzes. I've always liked the Red Llama/Tube Sound Fuzz but have noticed noise. So I didn't quite understand his statement. I might try to make the 4049 to 4069 adapter 2nite and see if it makes a difference. I'm still thinking those 2 150pf caps in the clipping stages could be raised since a typical muff has 470-560pf. I'm gonna try when I get home from work. Tempted to go home sick. I hate my job.

I was thinking the feedback loops, not clipping stages! typical muff circuits will have .05-.1uf caps in the clipping stages to block dc.

http://www.buildyourownclone.com/board/viewtopic.php?f=24&t=6006

the forum member also suggests adding a 470-560pf cap in the 1st fdbk loop but I don't know if these will work in the 22/7. I don't really understand the circuit very well in case you didn't notice.

[WGTP]

I'm no expert  , but doesn't using large resistors increase the noise?  My cmos designs try to use lower resistors by a factor of 10.  It won't work in all situations.

I know this changes the basic design, but using twice as many clipping diodes raises the output and lowers distortion, but the noise stays at the same level, increasing the signal to noise ratio.  The overall gain stays the same, but the output goes up.  Try a pair of LED's in each stage. 

For a different tone, leave the clipping diodes out.  This should provide the most output and the least noise.  I think.   (of course diode switching is an option) 

[Brymus]

OK guys here's my way of removing noise from CMOS builds.
Add a 10-22n at the V+ of the IC

From V+ to ground correct?

EDIT:
Putting the cap from the input to ground will help with possible oscillation and external noise
at the input but the noise I have is in the circuit somewhere not coming in through the input.
With the guitar vol rolled off the noise is still there.
I audio probed it and it starts after the first clipping stage (no surprise) and gets much louder
after the second clipping stage (no surprise).
The thing is that it's not just his but goes lower into the mid and lower frequencies.
I think it's a by product of the IC and this circuit.
Brian Tremblay, STM where are you?  

JOhn

Yes from V+ to ground
It wouldnt hurt to try on your breadboard and see if those two caps can knock the noise down some.
I just checked with my meter and I can get usable tones down to 2.7V by adding a 22n to ground at pin 1 of my 4049 UBE

[John Lyons]

I was thinking the feedback loops, not clipping stages! typical muff circuits will have .05-.1uf caps in the clipping stages to block dc.

That's true. I wonder why there are no cap between the diodes and the other end of the FB loop in the 22/7??

Bymus
I tried the caps and there was no change is the noise.
It does help with input noise via guitar and help with the
lower battery oscillation etc but the fundamental noise issue
is still very much there. I'll post some sound clips soon.

[Brymus]

OK John
Sorry that didnt work here. It does help the other CMOS builds be alot less noisy.
I guess some of the ROG guys will have to figure this one out.
BTW whats on my breadboard (a CMOS build) is going in one of the enclosures I ordered from you 

[John Lyons]

I appreciate the tips Bryan! It does help but just not the problem at hand.
I use a cap to ground on a few of the other pedals I make. Helps a lot!
This particular problem is in the circuit design I believe, Rather than noise getting in
at the input. The cap to ground on pin 1 is a good one though for future reference,
especially with batteries!

thanks for your help

John

[Brymus]

Did you guys get this problem sorted out yet ?
Please post the solution when it is resolved,I would like to understand as well.
thanks

[B Tremblay]

I recorded the 22/7 sound clips with the breadboarded circuit.  As you can hear, there is no overwhelming noise, despite the circuit being in a very vulnerable state.  Currently, the circuit and amp are within arm's length of a television, stereo receiver, wireless router, and fluorescent lamp.

I still have that circuit on the breadboard, so I hooked it up and I have no noise issues like others are describing.  Yes, there is background noise characteristic of a high-gain fuzz.  There is some white noise coming through when the guitar volume is at minimum, but not at a distracting level.

[John Lyons]

Here's a clip I made showing the background noise difference between a "Ram's Head" Big Muff and the 22/7.
These were done with a strat and a twin reverb.
The clips goes like this:
22/7in bypass, then on with full gain and tone about noon, then noise with guitar on, then the guitar's vol rolled off.
Second passage is the same thing with the Ram's head Big muff.
At the very end is a short segment of the 22/7s background noise (guitar vol off) then the Ram's head.
I bumped up the level of this but I didn't alter the levels between them.

www.basicaudio.net/Bigmuff-22-7.mp3

Am I crazy?

[juansolo]

Missed this thread, I also made a ROG 22/7 based on John's board. I also don't get any excessive noise... It's completely as stock across the board. I absolutely love this pedal, great with a SHO on the end of it too.

[juansolo]

Duplicate post

[John Lyons]

Nice  looking build Juan

Anyone listen to the clip?

[stm]

I listened to your clip.  Your noise is not "normal", it could be described as "waterfall noise", and sounds pretty much like pink noise as opposed to the white noise usually found in pedals.  Something is not working properly, most likely you have a "faulty" CD4049UB.  By "faulty" I mean faulty for *audio* purposes, since it would probably work OK as a logic IC.  Since there are other OK reports, including my protoboard build and Brian's, I suspect that some CD4049UBs are better than others for linear operation.

It would be very interesting if everybody that has build this circuit could post if background noise was "typical" or "excessive" and the brand/manufacturer of the IC.  I think some years ago there was a thread where a particular brand/manufacturer of CD4049UB IC was reported as unsatisfactory in comparison to other brand.

I am mostly interested in John Lyon's and juansolo info, as the results are opposite yet both use the same layout.  By the way, juansolo's picture of his (masterly accomplished) build doesn't let me read the IC brand!

P.D.  John, have you tried at least two different ICs with the very same result?

[John Lyons]

Sebastian
Yes, I have tried two different 4049 ICs.
I will get you those numbers and letters later tonight.



John

[stm]

Sebastian
Yes, I have tried two different 4049 ICs.
I will get you those numbers and letters later tonight.

John

The major interest here is in the manufacturer and eventually production batch.  The manufacturer can be told from the logo.  The production batch are usually four numbers below or above the P/N, representing the week and year  (two digits each) of the production lot.  A picture would be fine, assuming the lettering is readable, since sometimes it is very faint.