Wah transistors...should I care?

[axg20202]

I am about to build a wah based on the tonepad layout. Should I really care that much about transistor type? I've got plenty of 2n5088, 2n5089, MPSA18 etc. With all the talk about using BC109Bs (or similar), should I be that 'bovvered' or will it make next to no difference? Just wondering if it's actually worth making a special order to get some in. If it does make a fair bit of difference, I'd quick like to try some out. Should I be looking at BC109B, BC109C, BC107C or what? What's the difference in terms of tone?

I don't buy into all that tropical fish cap nonsense, but there might be something in this, at least for Q1.

Thanks,

Andy.

[jonathan perez]

there is no magical quality to the BC109...no mojo, just gain. what you need to think about is what amount of gain do you want on that transistor? anything above 500 will sound the same, really. 2n5089 have alot of gain, and the difference will probably be subtle to the untrained ear, in that they add more treble and bass to the overall sweep. bc109 have a nice balace and is probably the "standard" for transistors. otherwise, the resistors and capacitors that follow the transistors are really what you need to be concerned about. also, you DONT NEED TO BUY BC109 transistors. 2n4401 transistors will work very well.

[axg20202]

Thanks TBOM. Actually, I have some 2N3904s (max Hfe approx 300) which I could try as an alternative to the high gain NPNs I have. ??

[jonathan perez]

those will do the trick. 

[Paul Marossy]

I like the BC109Cs in a wah pedal. As mentioned, the actual type isn't terribly important. Lowering or increasing the gain of Q1 will make the most noticeable difference.

[axg20202]

Thanks guys. Looks like a case of 'socket and see'.