ATOMISOR New Version 2016

[tubelectron]

Hello All DIYstompboxers,

This pedal is not new, and certainly some of you will recognize its "retro-cool" look (below, at the right side) :



The original circuit that I built was a "modified Muff-Fuzz sounding à la Santana" kind of device that I barely used, so I decided that something new and more interesting could be done in that little box...

The ATOMISOR New Version 2016 is an overdrive-booster intended to give a boost added with just a bit of dirtyness to your sound, in order to help your amp reach the "sweet spot" more easily, at the stomp of a box.

Here is the schematic :



As you can see, this is a simple device (if we except the triple LED status indicator ) using a single Si transistor and a switchable Si / Ge clipper at the output. No gain adjustment, only the output volume. Gain variation are meant to be controlled by the volume pot on the guitar. Let's say that it is not a "clean boost" but a "dirty boost"...

Inside view (OK, it is not premium skillness wiring  , but it works as it should ) :



I will try to record some samples in the days to come.

Give it a go on your breadboard - you'll be surprised...

A+!

[kaycee]

Beautiful boxes there, love your style. Also the schematic is very pleasing to the eye. Good work!

[jizam]

Je ne suis pas capable de commenter sur la qualité du circuit ou du travail de soudure, mais qu'est-ce que ça envoie niveau look.
Absolument magnifique!

[tubelectron]

Thank you, guys !

"light-show" mode :

ON, 1 = Si clipping :



ON, 2 = Ge clipping :



The 1/2 switch has been replaced by a footswitch, but I could also add a switch for a linear, non-clip boost.

I'll post some soundsamples soon...

A+!

[digi2t]

As a millwright and electro-mechanic, that industrial look gets me every time. Reminds me of the German veneer equipment I used to work on year back. Gorgeous!!

[tubelectron]

Thanks !

Here is a sample of the ATOMISOR :

https://soundcloud.com/tubelectron/r05-0013-atomisor-new-version-2016mp3

Each small riff is recorded : 1/clean 2/Ge clip 3/Si clip, with : Bridge PU, then Bridge+Neck PUs, then Neck PU.

Hearing that, I notice that when I engage the effect, there is painful click  : I will have to correct that issue, sorry...

Here are the recording conditions :



And a closer view of the unit :



A+!

[Tony Forestiere]

IT  GOES   TO   13 !!! 

The clips sound very nice.

[tubelectron]

Thanks !

IT  GOES   TO   13 !!! 

Yes, that's pretty unusual and "diabolic" , along with the reversed "NO ! NO" FSW label and the ATOMISOR name

All of these nameplates comes from various leftover used equipments, going from cable-cars to medical devices...

Oh ! And my post numbers has just reached 666 with this last one... What an obscure coincidence  !

A+!

[mth5044]

Those are so awesome. Love the plates.

[escapeplan]

Really like the build aesthetic,  great job!

Sent from my SCH-I535 using Tapatalk

[tubelectron]

Thank you, Guys !

In the meantime, I added a 1M "antiklik" resistor at the input to GND, before the 47n, to avoid the noisy engagement/disengagement of the pedal.

A+!

[thermionix]

Man, I think that is the cleanest copy I've ever seen of the Gerald Weber book.  Mine isn't just dogeared, it's in five or six different pieces!

Love the Dano with the FilterTrons!  The pedal sounds awesome on the neck pickup especially.

[tubelectron]

Man, I think that is the cleanest copy I've ever seen of the Gerald Weber book.  Mine isn't just dogeared, it's in five or six different pieces!

Well, It is still in good condition because I don't read it so much : I do not find this book so much a "revolutionary" one on the subject...

Love the Dano with the FilterTrons!  The pedal sounds awesome on the neck pickup especially.

Thanks again !

My Danelectro DC59 Custom is a unique item, a one-of-a-kind lefty "fake", only borrowing the name and the overall design as a tribute to this genius brand and model, thanks to the skills of a good amateur-luthier pal.




I should have recorded it with a bigger amp than my COMET, like my SF PR and SF DR set near the clean limit, using the pedal to go in the "sweet spot" : it would have been more representative of the aims of the ATOMISOR... But I wasn't alone at home, sorry  ...

A+!

[tubelectron]

Edit, for those who are interested :

I added the 1M input resistor to suppress the switching pops that I spoke about.

I added a 1M // resistor on the 3M3. This modifies the biasing of the 2N2219 and allow some slight tone improvement : attacks are more neat, less intermodulation, decay more regular, more drive and more output level. The difference is not huge, but noticeable to be worth to be done.

I used my Dano Custom and my Fender Deluxe Reverb SF, at " still clean close to sweet spot" level, to check this (sorry, I didn't took the time to record samples  ).



A+!

[Cozybuilder]

If you're getting a pop when switching the diodes, you might consider this alternative:

[M.A.P]

Hi Bruno,

the pedal sounds great and is only outreached by its incredible look! I love old electrical devices and your pedal really catches that look perfect.

The 1M and the parallel 3M3 resistor could be replaced by a single 750k resistor.

@Russ: That's a really nice solution for the changing of the diodes. Is it an on-off-on swith or an on-on switch in your drawing? If it's an on-off-on you would have all ge an si diodes in a row.

Greetings from Germany,
Marcus

[Cozybuilder]

Hi Marcus- and thankyou 

I was just looking at this as being half of Bruno's NO-NO footswitch. But yes, an on-off-on would give a third flavor- something to file away for a future build.

[tubelectron]

Thanks M.A.P and Cozybuilder !

the switching of the clipper is done via the upper "1/2" FSW, and I do not experiment klikz here - nonetheless your idea is good and would probably cure the issue if it occured here. The kliklaklok problem was at the NO-NO FSW : I forgot the resistor to discharge the potential of the 47n input cap, so I added here the 1M to GND.

Yes, I was hesitating between putting a 750K or a 820K, and finally I put a 1M in // because it is the value that I found with my decade box put in // on the 3M3, and I'm lazy, OK. Since my wiring in this pedal is not premium grade at all, this is not of a major importance

As you mention it, I tested the disconnection of the clipper : it has no sounding interest IMHO, the transistor sounding not so clean itself. I did not tested the "serial" clippers according to your drawing : I think that the gain of the circuit would be too low to give a significant clipping in that configuration, but I could perform a test to check, nonetheless...

What I should test, interestingly maybe, would be the use of a FET instead of a bipolar. Maybe it would be another further improvement in the overdriven tone ?

A+!

[tubelectron]

End of the story : a last sample of the updated ATOMISOR with the Dano and my Princeton Reverb SF :

https://soundcloud.com/tubelectron/r05-0008-atomisor-new-version-2016-prmp3

A+!

[Jamdog]

That box looks awesome!