Fuzz for beginners

[GibsonGM]

There is interaction between the bias voltage and the collector voltage, LSG - so your deduction is both logical, and correct

[LightSoundGeometry]

I have two of the rangemaster built from the small bear transistors..best sounding pedals I have ever used/heard that I have built and just as good sounding as about any own including a lumpys & analogman beeno ..except I am only getting like .1ma on collector and like zero or nothing on the B n E

puzzles me but I am new and learning ..this is the gold legged "US NPN" branded transistor ..I left the heat shrink short so I can get my probe on the legs to take readings .

only modification I did was the 100K range pot instead of the 10k range and used a 2.2n tropical fish instead of a 5n on C2

[mfunky]

mfunky-
I stuck the 22K in series with the 220p to dial back the treble a bit, its more of a Germanium sound to my tin ears, you might prefer a different value (or none).

A lower C3 brought up the treble a bit, before that it was too dark (IMHO). R5 and R6 were chosen to give 4.5V at the collector. Basically, try 1K for R5, and a 10K pot for R6, adjust to 4.5 volts, play & listen, adjust the bias until you like it, and read the pot value. Add 1K for total R, and choose 2 fixed resistors that will get you very close to the total R. R5 should be near 1K (I like 1.2 - 1.5K). Don't be surprised if you wind up with under 5K total resistance needed.

Changed R5 to 330R, left C3 at 33nF (I have a bright amp/guitar setup, so this was ok for me). I measured the voltage at the collector of Q2, measured the trimpot afterwards and replaced it with a fixed R of 3,9 K. So yes, I ended up with under 5 K total resistance (and like what I hear).

The attack pot gives a lot of versatility, this is really a more important control than "smooth"- you can use a fixed R for that.

I think if you use 9mm pots you will be able to fit a 3-pot Axis Face into a 1590A with battery. You will have to be clever about the component types and locations of course- but the necessary volume is there. Good luck, I may do one also, it really is a great sounding pedal.

Unfortunately, I already veroed it, so it is too late for that. But I plan to build a couple of those as gifts and will try the other suggested changes on the next build. Thanks for your support, man!

[mfunky]

P.S. Vero layout:



Adjust the "no trim" resistor for 4.5 V on the collector of Q2. Add a pulldown resistor (1M) on the input jack (tip-shield) and add a voltage stabilizer electrolytic capacitor (100uF) on the power jack.

[plexi12000]

Thanks for the great info Mark Hammer!  REALLY insightful for those of us "still in diapers"--

[Cozybuilder]

P.S. Vero layout:



Adjust the "no trim" resistor for 4.5 V on the collector of Q2. Add a pulldown resistor (1M) on the input jack (tip-shield) and add a voltage stabilizer electrolytic capacitor (100uF) on the power jack.

If its still too dark when you add resistance at the smooth pot, you could try a small bypass cap directly onto the pot (lugs 2 and 3)- try clipping it in place first, see if you like it, try different values. This is a mod that doesn't require Vero soldering.

[mfunky]

If its still too dark when you add resistance at the smooth pot, you could try a small bypass cap directly onto the pot (lugs 2 and 3)- try clipping it in place first, see if you like it, try different values. This is a mod that doesn't require Vero soldering.

Great, I did not think of that (although I have done similar stuff on guitar volume pots like a hundred times...) ! These 1590a-Projects (especially the ones with battery) are killing me! Whatever you do, there is always room for EVEN MORE components to stuff in there!!!

[Cozybuilder]

Wait until you try the 1590LB! There is a lot of room to work with once you work out the geometry of the necessary hardware. "Keyring" pedals.

[mfunky]

This will work. One pot more than in my last build [emoji6]

[mfunky]

Done!

[LightSoundGeometry]

not a fuzz but I am making progress with the 1590a boxes

[tubelectron]

Done!

Fine mfunky !

I was wondering if a 2-knobs Fuzz (or overdrive) would enter a 1590A box along with a 9V battery : the answer is yes, looking to your release.

- It seems though that the very compact jacks sockets you use here are not supply-cutting when unplugged : right ?

The idea of using the supersmall pots is good also.

For my FuzzRite 2000 Pound Bee Ventures Model, I used a 12V battery, because I could not enter the classic 9V battery like you did :







A+!

[mfunky]

Nice! How long does the 12 v battery last ? And to answer your question: the input jack is stereo and does break ...

[tubelectron]

Nice! How long does the 12 v battery last ? And to answer your question: the input jack is stereo and does break ...

Thanks mfunky !

I finished my FuzzRite in 2011, and the A23 12V battery is still the original one. That pedal, when engaged (led ON), absorbs only 150µA. The battery will probably die of old age...

You're lucky : I never could find that model of jack in stereo, only in mono : that was the aim of my question... Do you remember by chance where you sourced it ?

A+!

[mfunky]

Nice! How long does the 12 v battery last ? And to answer your question: the input jack is stereo and does break ...

Thanks mfunky !

I finished my FuzzRite in 2011, and the A23 12V battery is still the original one. That pedal, when engaged (led ON), absorbs only 150µA. The battery will probably die of old age...

You're lucky : I never could find that model of jack in stereo, only in mono : that was the aim of my question... Do you remember by chance where you sourced it ?

A+!

Good to know, that these batteries work for (low current) circuits. I know exactly, where I sourced it: http://uk-electronic.de/onlineshop/product_info.php?products_id=1219&osCsid=4ffbfe9615e1a54bc8f0e9b172ca258c

Or do a search for Lumberg KLBS (if you are not in Germany/Europe).