My First Build - Colorsound One Knob Fuzz (Dragonfly's Layout)

[py5ir5]

Hello all

Please see some pictures of my first build - a Colorsound One Knob Fuzz, as per Dragonfly's Tutorial (Thank you). This is possibly THE most expensive stompbox ever, but fills me with an enormous sense of well being and achievement. Extended thanks to all who contribute to these and similar DIY pages, the information has proved its worth a thousand fold. Thank you.

Mothra sounds amazing, I thought it was good at home through an M-audio black box, but on Thursday I played through a nice Vintage Marshall JMP and it sounds Oh So Good - a genuinely usable loud fuzz.

So, now some questions.

1) Where in the UK (Ideally London)can I buy some coloured Davies Pointer 1510 type knobs? I'm thinking of red or orange for this one; also some of those plastic barrel 2.1mm DC sockets?

2) I have used the BC108 & BC109 as specified for this circuit, but I'm interested in finding out a little more about how/why these particular ones are used instead of say 2n2222(?) other than the Hfe/ gain what qualities do different transistors (Silicon) have? Is there some way to determine how things might sound e.g. sharp/ metallic or muddy/ gloopy sounding depending on a particular transistor. Any pointers here would be greatly appreciated.


Thank you and Good Luck

Iain

[skrunk]

banzai is good for knobs:

http://www.banzaimusic.com/Pointer/

Is there some way to determine how things might sound e.g. sharp/ metallic or muddy/ gloopy sounding depending on a particular transistor.

you should pick up a breadboard too, essential for trying out how different components sound:

http://www.banzaimusic.com/Breadboards/

lots of breadboard projects and other info at beavis' site to get you started:

http://www.beavisaudio.com/bboard/projects/

[makaze808]

Congrats on a nice build. When wondering about trannies and diodes input/output caps effecting or shaping the sound the answer is always to get a circuit breadboarded and play around. It was a process I was slow at starting and regret that. All my keepers are not as spec'd in the posts, at the end of the day if they are for you then you won't lie to yourself.

There is a tendency to want to mod for modding sake, but trannies are great to swap about. I have discovered some great boxes to match particular amps.

PLAY TIME and ENJOY.

Best Wishes.

Woz.

[makaze808]

Get small boxes dude.

[petemoore]

  It looks like the board connections could touch the box.
  A piece of anything insulative [I like clear thick plastic stuff used for theft preventive/sealed packaging, free] slid under/sized or other/so it has to stay in place is a good preventative measure.
  Otherwise looks very very ugly, as only Mothra can.

[deadastronaut]

bitsbox will do the bits your after.uk based..great service too...online..

dont bother with maplins, they are thick and pricey.........

or dr tweek is also on here too...........welcome to you as a fellow  uk diyer'.

[py5ir5]

Thank you for your replies,

Banzai do seem to be the only provider of those Davies style 1510 knobs I'm after this side of the Atlantic. I'll have to wait until I've got some more to buy to make the shipping costs worth it.
Bitsbox are great, I got a fair bit of stuff from them - good service from a person, but they don't have much in the way of knobs (Oooh err)
Other stuff I bought from Rapid - they're pretty good too.
Maplin - only when absolutely necessary.

I will get some of that sticky back foam to prevent the board from touching the case.

As for experimenting with different transistors/ caps etc. I do have a breadboard and have changed values etc to see what would happen and this is very much part of the fun, but what I'm after is a more scientific understanding of the sonic differences of two different transistors. For instance let's say

Transistor A (say a BC108) has gain (Hfe) of 100
Transistor B (say a 2n2222) has gain (Hfe) of 100

So they should sound the same, but let's say in the same pedal Transistor B sounds 'tinnier' than Transistor B, but has longer sustain. This is because...

Transistor B's larger design includes a greater surface area which contributes a minute amount of capacitance, which combined with the resistors in the signal path adds an element of filtering around the 20khz mark, therefore reducing the higher harmonics a touch. This effect happens in all transistors designed in this way

Or the current in Transistor A dissipates faster, so the audio signal attenuates faster, hence less sustain. This is a known effect of these types of transistors

I'd like to know if there is some quantifable, measurable qualities in addition to the Hfe that one could use as a reference when desiging audio circuits. So one could compare and perhaps anticpate the behaviour of the transistor and circuit, rather than simply trying every single transistor in the world, particularly where a circuit has more than one transistor then the combinations would quickly become bonkers.


Any ideas, thoughts and comments welcome.

Iain