22/7 is a CMOS-based version of the Big Muff Pi. Check it out: http://runoffgroove.com/22-7.html
Three clips are available on the Sounds page: http://runoffgroove.com/salvo.html#227
We've also added an article describing construction of a pinout-matching module for the 4069 CMOS chip. Build one and use the 4069 in 4049-based layouts: http://runoffgroove.com/6949.html
awesome! this is definitely going on the list ;D
How does this compare to earlier versions of the 22/7? There used to be a switched filter in the input stage (rev. 1.3, schem by gaussmarkov). What happened to that?
The PCB ordering page will be up soon.
John
+1, on CMOS Big Muff and the clips ! Very cool !
..just when the BMP has finally taken a position of prominence on my PB..
Interesting idea. Sounds pretty cool.
Brilliant.
Also, the 14pin 74HCU04 suggested by Tim Escobedo is a good chip to use. Don't forget to try LED's as well. :icon_cool:
Very interesting...thx a lot B. Tremblay!
I've built sometime ago an earlier version, but it had too much hiss. Is this version better from this point of view?
Quote from: Ben N on October 05, 2009, 09:57:45 AM
How does this compare to earlier versions of the 22/7? There used to be a switched filter in the input stage (rev. 1.3, schem by gaussmarkov). What happened to that?
The early versions had a BOOST switch at the input. It provided more gain than a stock BMP, but it also raised the noise floor and produced too much trouble with hum and oscillation, therefore it was discarded in later revisions. Besides that, is wasn't a filter per se, as it didn't affect the frequency response in the audio band. More to read here: http://www.diystompboxes.com/smfforum/index.php?topic=55237.msg424565#msg424565
The new circuit has a three-position switch in the tonestack that provides two additional sounds apart from the CLASSIS tonestack. The SCOOP mode has a deeper notch, but not as much as the one found in the Swollen Pickle, as we found this setting too extreme and introduced an appreciable attenuation as well. Nevertheless, if a deeper notch is desired, it is a matter of replacing the 10n extra cap with a 22n cap, or even a 33n cap (which would produce the notch depth as in the S.P. The FLAT mode is a very nice addition, as it produces a sound that can cut its way through the band nicely, especially for leads and solos.
A final note, I just noticed the early schems (1.2, 1.3) in the contest threads are gone. I didn't take them down on purpose; they were hosted at tynipic.com and apparently they were removed due to a long period of inactivity. Please refer to the official release now.
P.D. The 4049 to 4069 adapter module adds the possibility to answer the old question: Is there an audible difference between a 4049 and a 4069? After all, the output current capabilities are different, so it is very likely that it should have a sonic impact somehow.
Looks blissfully simple, and sounds great. I'm just happy that Divide-By-13 didn't produce it, or else the folks in the music stores would be in trouble:"Hi, do you have the 22-divided-by-13, over 7, pedal? or maybe it's the 7-divided by 13/22. Wait a sec, I have it written down here somewhere." :icon_wink:
Quote from: Mark Hammer on October 05, 2009, 12:33:04 PM
Looks blissfully simple, and sounds great. I'm just happy that Divide-By-13 didn't produce it, or else the folks in the music stores would be in trouble:"Hi, do you have the 22-divided-by-13, over 7, pedal? or maybe it's the 7-divided by 13/22. Wait a sec, I have it written down here somewhere." :icon_wink:
:-)
Cool. It's on my list. I'm glad to see you guys are still working on new builds!
Sounds great, man!
WOW that sounded sweet! Very 1969
Thanx ROG for another great circuit,and thanx John for the transfer layout.
Also the tut on the 4049-4069 was really nice too.Should be helpful to lots of people who use the 4049 in pedals.
I look forward to the next build you guys post :icon_exclaim:
Thanks again R.O.G. You rock!
(http://i111.photobucket.com/albums/n140/tol30/DSCN1628.jpg)
Here's my 22/7 built with a sweet basicaudio pcb. Has anybody had any success in lowering the noise in their build? I really love the sound and 'feel' of the pedal. John was saying it's thermal noise rather than power line noise. I am going to try a larger value cap instead of the 100uf to see if it minimizes any hum/hiss but is there somewhere else we should be looking? In a typical bmp there are 470-560pf caps in the clipping stages to block dc. Should we be changing some values there?
There is a discussion on thermal noise from last March here:
http://www.diystompboxes.com/smfforum/index.php?topic=75340.0
Mine is noisy as well. It sounds like thermal noise but I don't know for sure.
Sounds like listening to a large waterfall with your hands covering your ears.
A pink noise if you will. Full frequency noise as you can here low mid and high end hiss.
It's about 3 times as loud of as the big muff variants I've compared it to.
I get relatively little hum or outside noise, just the constant hiss.
With the gain lowered it's less but even with the "sustain" all the way off
It's still there just lower. I'm using all metal film resistors so I don't think
it's thermal noise in the resistors.
I have used 2 different brands and prefixes of 4049 ICs with the same result.
I built a second one just to be sure, same deal.
Is this IC related? I seem to remember the Red Llama being noisy as well.
Other than the noise this thing rocks!
Any ideas?
John
just finished putting mine together with the basic audio layout. sounds awesome and no noise even with switchmode wallwarts on the same powerboard as my pc. running it through my valvecaster into a 50w ss combo and the sound is HUGE (seymour duncan invader pup helps..)
OK so I replaced the 100uf cap with a 220uf and I fancy I hear less noise especially in the low end but I may just be fooling myself. Will somebody try it on theirs and tell me I'm crazy?
Just tried it but didn't hear any difference.
That cap is a reservoir cap to smooth DC ripple
that may be in the line after the typical 1000uf
smoothing cap in you AC adaptor power supply.
It's a local, sort of buffer of DC power...
I need to audio probe the board again...
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.
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 :icon_lol:
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
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. :D
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. :icon_wink:
Quote from: Brymus on January 22, 2010, 01:07:03 PM
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? :D
JOhn
Quote from: tol on January 22, 2010, 09:43:49 AM
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.
I'm no expert :icon_rolleyes:, 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) :icon_cool:
Quote from: John Lyons on January 22, 2010, 01:24:50 PM
Quote from: Brymus on January 22, 2010, 01:07:03 PM
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? :D
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
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.
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 :icon_biggrin:
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
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
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.
(http://runoffgroove.com/227proto.jpg)
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 (http://www.basicaudio.net/Bigmuff-22-7.mp3)
Am I crazy?
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.
(http://farm3.static.flickr.com/2485/4079939747_3466a41501_o.jpg)
(http://farm3.static.flickr.com/2600/4060215705_6fb0c921c6_o.jpg)
Duplicate post :icon_frown:
Nice looking build Juan
Anyone listen to the clip?
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?
Sebastian
Yes, I have tried two different 4049 ICs.
I will get you those numbers and letters later tonight.
John
Quote from: John Lyons on January 26, 2010, 10:52:58 PM
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.
My chip is a Fairchild CD4049UBCN (http://pdf1.alldatasheet.com/datasheet-pdf/view/50855/FAIRCHILD/CD4049UBCN.html). I'm guessing the production number is PJ25AH. Bought the chip from Rapid, it's in their catalogue as unbranded, but what we got was a Fairchild.
Mine definitely isn't making the noise that John's is. Nothing like that at all.
The ICs I've used are:
Fairchild CD4049UBCN Batch P9948AK
Texas Instruments CD4049UBE Batch 3CE1H4K
Those are the only two types I have.
I tried a few from each type....
Thanks for the info juansolo.
John, based on the info available on the chips, I think it is safe to assume that the chips are not the problem.
The kind of noise you have might be caused by some sort of oscillation. Possible causes for oscillation are:
1) Unused inputs not grounded or Vcc'ed (this should not be the problem since the layout takes care of unused inputs.)
2) Power supply quality and filtering. The 470R and 100uF capacitor should filter the power supply adequately, however we should suspect these components until we prove they are OK. Principal suspect would be the 100uF capacitor. Things to do:
a. Check polarity as mounted in the PCB
b. Replace with a different cap, let's say a 10uF to 100uF WITH a 100nF ceramic or polyester capacitor in parallel.
c. Reduce the value of the 470R resistor, probably reduce it first to 100R, then just place a wire jumper, and see if the noise character changes. These tests should be performed with a battery to eliminate the possibility of noise coming from a power adapter.
3) Layout issues. This would not be the first time where the wires and the tracks layout give trouble. This is a relatively high gain circuit and should be treated with some care.
a. In your layout the 1k resistor from the gain pot returns to GND sharing a common path with the power supply filter capacitor. I'd suggest lifting the GND end of said 1k resistor and connecting to a different place far apart, let's say the GND of the 1M resistor in the tonestack.
b. The GND wires from the input/output jacks, as well as the volume pot and the power supply could be causing trouble. I suggest changing the connections to see if there is some effect. One thing to try would be a single GND point where all GND wires converge. A suitable point would be the GND terminal on the PCB
The cause for the oscillation must lie somewhere along the lines described above.
Regards and good luck.
Quote from: stm on January 28, 2010, 07:24:43 AM
Thanks for the info juansolo.
John, based on the info available on the chips, I think it is safe to assume that the chips are not the problem.
The kind of noise you have might be caused by some sort of oscillation. Possible causes for oscillation are:
1) Unused inputs not grounded or Vcc'ed (this should not be the problem since the layout takes care of unused inputs.)
2) Power supply quality and filtering. The 470R and 100uF capacitor should filter the power supply adequately, however we should suspect these components until we prove they are OK. Principal suspect would be the 100uF capacitor. Things to do:
a. Check polarity as mounted in the PCB
b. Replace with a different cap, let's say a 10uF to 100uF WITH a 100nF ceramic or polyester capacitor in parallel.
c. Reduce the value of the 470R resistor, probably reduce it first to 100R, then just place a wire jumper, and see if the noise character changes. These tests should be performed with a battery to eliminate the possibility of noise coming from a power adapter.
3) Layout issues. This would not be the first time where the wires and the tracks layout give trouble. This is a relatively high gain circuit and should be treated with some care.
a. In your layout the 1k resistor from the gain pot returns to GND sharing a common path with the power supply filter capacitor. I'd suggest lifting the GND end of said 1k resistor and connecting to a different place far apart, let's say the GND of the 1M resistor in the tonestack.
b. The GND wires from the input/output jacks, as well as the volume pot and the power supply could be causing trouble. I suggest changing the connections to see if there is some effect. One thing to try would be a single GND point where all GND wires converge. A suitable point would be the GND terminal on the PCB
The cause for the oscillation must lie somewhere along the lines described above.
Regards and good luck.
2) b. WITH a 100nF ceramic or polyester capacitor in parallel.
3) a. I'd suggest lifting the GND end of said 1k resistor and connecting to a different place
b. One thing to try would be a single GND point where all GND wires converge
i.e.: at the 100uF negative pin.
Doesn't that contradict what was said?
If the star ground point was the neg pin of the 100uf cap then
why should I remove the 1K from that point.
I understand that that point (100uf pin 1) is a high(er) current ground point but the board is small...
Moving the 1K to a point down the line near the tone section is closer to the end
of the circuit...won't that be a "dirtier" ground point...not sure that it maters much at
9v though...
Thanks for the Tips STM.
I'll try them out tonight.
EDIT:
Ok, tried everything above. still get the background noise, no change :(
The board has a single ground point that connects to the battery and in/out jacks.
Lowered the series power resistor, ceramic .1 across the (new) 100uf cap.
1k moved to the other side of the ground trace.
John
Kinda wanted to bump this, as I don't see it built often, but it's a very cool twist on the classic BMP.
Also, I made this layout:
(http://i131.photobucket.com/albums/p315/naazrael/TwentyTwoSevenths.gif)
Not verified yet, and actually a second of set of eyes to check for errors would be welcome. :D
John, did you ever alleviate your noise problem?
for your eyes only: :icon_cool:
http://www.diystompboxes.com/smfforum/index.php?topic=85661.0 (http://www.diystompboxes.com/smfforum/index.php?topic=85661.0)
one can never have enough pi !
oh yes, I saw yours. That was actually a big inspiration for mine, I wanted to compact it a lot more, wanted to fit it in like a 1590B or so. :D
Wanted to bump this, had a thought: For those having problems with noise, did you try grounding the unused inputs on the 4049?
Quote from: azrael on March 11, 2012, 12:52:12 AM
Wanted to bump this, had a thought: For those having problems with noise, did you try grounding the unused inputs on the 4049?
Hopefully they did, as there is a note on the schematic that those pins are to be grounded.
Did you have any noise issue with your layout?
Oh, never built it. I actually missed that note on layout, haha, so it's possible others did.