Tube scream

[RobA]

Socket the op-amp. The 4558 makes this circuit. 072 sounds harsh, 5532 sounds mushy and fuzzy, LM833N is pretty good but is a bit too hard, OP2134 sounds much like the 072, etc. The second stage, the high shelf filter, would do better with most any of those I just listed, but the distortion is just so much better with the JRC4558D that the reduced noise is meaningless. Put it in a socket and test for taste yourself.

I like playing with clipping diodes. I like LED's and mosfet clippers and Ge diodes and anything else you can think of, but none of them work as well in the TS circuit as just the 1N4148 diodes. The circuit, with stock components, just must be tuned to make those diodes yield that smooth but aggressive sound. I do like the asymmetric/symmetric mod though.

Box film caps. The cap in the tone control is fairly critical. It needs to be a good stable cap (i.e. not ceramic).

All that said, it's a great circuit to breadboard and play with yourself to find out what you like. It's the only way to really figure out what's best to you. Tube Screamer, Distortion+, and Big Muff are all great to breadboard and experiment with.

Rob 

[gtangas]

Nice explanation

I bought an 072 and a 833n I couldn't find the jrc

As for the diodes 2x3mm yellow led and 3 1n4148

I had a bad time finding box film caps.... I will try another Shop in Lisbon a try to find them... Or else tayda. Com

I'm populating the board and justo stop for a smoke 

I will add all the switches.

I love build this things man!

Again Thx for the tips

Hope to soon share my TS

[RobA]

Since you are in Europe, you can get most stuff for DIY electronics at decent prices in reasonable quantities from Banzai (http://www.banzaimusic.com). I used to get stuff there when I lived in the UK and their shipping was pretty fast and not too bad on the costs.

[gtangas]

The prices from banzai are higher than tayda. In terms of shipping time I don't have the experience but from tayda things arrives in 7/9 days to Portugal.

Here in Portugal Is f *** difficult to think things like box film caps, pots that aren't made of plastic, precision resistors, etc.... Even in Lisbon

And with this economic recession.... Ui! A lot of the old shops that I remember visiting with my father (and I'm 40 years old) where you could find most of this stuff are closed.

But thank god for the e shops hehehe

[RobA]

For the stuff that Tayda has, they are certainly cheaper. But Banzai does carry things you aren't going to find at most any electronics source. When you need to buy in large quantities, Rapid and Farnell are pretty good sources in Europe.

[gtangas]

i´m confuse with two things (for the moment...      )

I will use two yellow led on D4 and D5. According to some browsing that i made on polarity of led vs the diode i think this the correct polarity of the led.



but normally the square pads are for V+...

The other thing is the wiring of the fat or bright switch. is this wiring correct?



thx
Sergio

[pedalman]

the switch calls for a single pole single throw (just 2 prongs) you have a double throw in the pic
this is just a make/break connection

as far as the diode goes im not sure what your trying to do
are you trying to do a diode mod ?

[gtangas]

the switch calls for a single pole single throw (just 2 prongs) you have a double throw in the pic
this is just a make/break connection

as far as the diode goes im not sure what your trying to do
are you trying to do a diode mod ?

I'm replacing these diodes for 3mm leds..
My doubt is the polarity of the led vs the diode.

According to some research the stripe of the diode indicates the ground side and that way I soldered the flat side of the led to that side.

My question is if that right?

[pedalman]

think you got it backwards
stripe is the +
long led on the led is +


       1N914     1N914    LED
          l   l          l   l       l  l

+ -----l   l--------l   l-----l   l------ -
   
          l__l          l__l     l__l
      jumper      jumper    jumper


on/on dpdt

[gtangas]

I found this

[gtangas]

I found this



And according to it and the Pcb diode orientation I soldered the way I told early

But as the square pads normally indicates the +v... I start thinking that something was wrong

[pedalman]

i dont think thats right, square pad is a +

[Stomptown]

i've done a couple of tonepad screamers, and something doesn't quite sit right, maybe it's just me :/

George

I agree! Somethings definitely off with the tonepad version of the TS! I built a couple from BYOC when i first started building and they sounded far better. I need to give the bean board a try soon...

[RobA]

The bar on a diode is the cathode, the "-" side. So this corresponds to the short leg of the LED or the flatted side. The square pad for the diode is the cathode side, but for a crowbar diode (the 1N4001) used as reverse polarity protection, the square pad sits on the +9V side. But, that's because it's only supposed to conduct when the polarity is reversed.

Rob

[alanp]

It's easier to think in terms of current will flow from the unmarked end TO the marked end, but NOT in the other direction. With how diodes get used in all kindsa ways, any other train of thought does my head in.