madbeanpedals::forum

General => Open Discussion => Topic started by: gtangas on January 29, 2013, 02:48:15 PM

Title: Tube scream
Post by: gtangas on January 29, 2013, 02:48:15 PM
Hi guys

Need some help on building a tube sreamer

I saw on the Madbean projects but there isn't an etch board

Any help?
Title: Re: Tube scream
Post by: stecykmi on January 29, 2013, 06:26:32 PM
tonepad.com has a etch layout with a few common mods.
Title: Re: Tube scream
Post by: gtangas on January 29, 2013, 06:50:24 PM
Quote from: stecykmi on January 29, 2013, 06:26:32 PM
tonepad.com has a etch layout with a few common mods.

Yes I have seen it. But I am a Madbean builder lol

I like the way Brian build this babies :-)

But will check it again

Thx
Title: Re: Tube scream
Post by: Vallhagen on January 29, 2013, 07:07:52 PM
Quote from: gtangas on January 29, 2013, 06:50:24 PM
But I am a Madbean builder lol

Good thinking;)

There IS an open madbean TS project right here on the forum. Gimme a minute, ill find the link.

Cheers

EDIT: Here you go:
http://www.madbeanpedals.com/forum/index.php?topic=1661.0

Cheers
Title: Re: Tube scream
Post by: slimtriggers on January 29, 2013, 07:45:05 PM
I've built both the Tonepad and the Open Source Madbean TS.  I like the Madbean layout better  8)
Title: Re: Tube scream
Post by: hammerheadmusicman on January 29, 2013, 11:01:50 PM
i've done a couple of tonepad screamers, and something doesn't quite sit right, maybe it's just me :/

George
Title: Re: Tube scream
Post by: gtangas on January 29, 2013, 11:28:04 PM
that´s why i´m a MD builder!  ;D

Ok so i was looking at the layout/pcb and i need some help.

I think the switch is ok but what is the "1" for?
(http://i775.photobucket.com/albums/yy38/gtangas/TS_zps0aa5613b.jpg)

another question:
I've seen in different projects that diodes are replace by leds... clipping mode.. why? more gain? can i use a normal led?
Title: Re: Tube scream
Post by: jkokura on January 29, 2013, 11:36:27 PM
Not positive, but it might be for the empty lug of the switch you already drew in...

Jacob
Title: Re: Tube scream
Post by: Haberdasher on January 29, 2013, 11:44:48 PM
1 goes with pads 2 and 3 (above d2 and d3) for the comp switch that lets you choose between different clippers.
when using leds for clippers most people use 3mm red leds wich sound the same as 5mm red leds but are easier to fit.
Title: Re: Tube scream
Post by: gtangas on January 30, 2013, 12:44:11 AM
Quote from: Haberdasher on January 29, 2013, 11:44:48 PM
1 goes with pads 2 and 3 (above d2 and d3) for the comp switch that lets you choose between different clippers.
when using leds for clippers most people use 3mm red leds wich sound the same as 5mm red leds but are easier to fit.

ok, i have two comp switchs? one for fat and another for the clippers?

In that case can i change these diodes for leds?
Title: Re: Tube scream
Post by: Haberdasher on January 30, 2013, 12:51:19 AM
there are 3 switches available:  fat, bright, and comp.  the explanation for what they each do is on the schematic and there's probably lots of info in the green bean doc as well.

yes you can use led's.  I used them in d4 and d5 and used 3 bat46 type for the others.  I don't remember being completely sold on the bat46.  I'd probably like plain old 1n914's better. just socket them if you want & experiment around.
Title: Re: Tube scream
Post by: slimtriggers on January 30, 2013, 01:04:47 AM
Quote from: Haberdasher on January 30, 2013, 12:51:19 AM
 I'd probably like plain old 1n914's better. just socket them if you want & experiment around.

I feel bad about admitting I like 1n914/1n4148 better than other clippers I've tried-at least in the Tubescreamer.  Also, I've never been able to tell a difference in opamps in a TS circuit.  Maybe there's something wrong with me (http://fc06.deviantart.net/fs15/f/2007/060/2/4/_crazy_by_sml_e.gif)
Title: Re: Tube scream
Post by: Haberdasher on January 30, 2013, 01:38:28 AM
Quote from: slimtriggers on January 30, 2013, 01:04:47 AM
Quote from: Haberdasher on January 30, 2013, 12:51:19 AM
I'd probably like plain old 1n914's better. just socket them if you want & experiment around.

I feel bad about admitting I like 1n914/1n4148 better than other clippers I've tried-at least in the Tubescreamer.  Also, I've never been able to tell a difference in opamps in a TS circuit.  Maybe there's something wrong with me (http://fc06.deviantart.net/fs15/f/2007/060/2/4/_crazy_by_sml_e.gif)

You're not alone.  1n914's are my favorite.  I used to buy a lot of diodes thinking I'd find something exotic, but truth is 1n914's just sound right.  Love them in a timmy.
As far as opamps, about the only time I've really ever appreciated a change was when I dropped a opa2604 in the serendipity.  I'm not sure why but it just sounded at home there, but in most other circuits they all sound about the same to me.

In all honesty though, I'm not the world's biggest tubescreamer fan so I probably shouldn't be doling out lots of advice concerning it.  I would just urge folks to socket the diodes and play around. :)
Title: Re: Tube scream
Post by: gtangas on January 30, 2013, 12:00:10 PM
Quote from: Haberdasher on January 30, 2013, 01:38:28 AM
Quote from: slimtriggers on January 30, 2013, 01:04:47 AM
Quote from: Haberdasher on January 30, 2013, 12:51:19 AM
I'd probably like plain old 1n914's better. just socket them if you want & experiment around.

I feel bad about admitting I like 1n914/1n4148 better than other clippers I've tried-at least in the Tubescreamer.  Also, I've never been able to tell a difference in opamps in a TS circuit.  Maybe there's something wrong with me (http://fc06.deviantart.net/fs15/f/2007/060/2/4/_crazy_by_sml_e.gif)

You're not alone.  1n914's are my favorite.  I used to buy a lot of diodes thinking I'd find something exotic, but truth is 1n914's just sound right.  Love them in a timmy.
As far as opamps, about the only time I've really ever appreciated a change was when I dropped a opa2604 in the serendipity.  I'm not sure why but it just sounded at home there, but in most other circuits they all sound about the same to me.

In all honesty though, I'm not the world's biggest tubescreamer fan so I probably shouldn't be doling out lots of advice concerning it.  I would just urge folks to socket the diodes and play around. :)


Then I will use 3mm leds on D4-D6, TL072 for the opa, and D1-D3 1n914

And what caps? ceramic? Film? Box?

I hallways have difficulty on the choice of caps (not the electros  ;D)
Title: Re: Tube scream
Post by: pedalman on January 30, 2013, 03:58:29 PM
i permanently bridged 2 & 3 and didnt use the comp switch. by doing this it removed D1-3.
D4-5 were lifted offboard for crazy options. more to come
Title: Re: Tube scream
Post by: RobA on January 30, 2013, 06:17:41 PM
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 

Title: Re: Tube scream
Post by: gtangas on January 30, 2013, 11:17:45 PM
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  ;D

I will add all the switches.

I love build this things man!

Again Thx for the tips

Hope to soon share my TS
Title: Re: Tube scream
Post by: RobA on January 30, 2013, 11:51:36 PM
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.
Title: Re: Tube scream
Post by: gtangas on February 01, 2013, 10:39:55 AM
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
Title: Re: Tube scream
Post by: RobA on February 01, 2013, 01:30:09 PM
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.
Title: Re: Tube scream
Post by: gtangas on February 02, 2013, 11:57:26 PM
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.

(http://i775.photobucket.com/albums/yy38/gtangas/diodevsled_zpsa946221d.jpg)

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

The other thing is the wiring of the fat or bright switch. is this wiring correct?
(http://i775.photobucket.com/albums/yy38/gtangas/switch_zps1807ca18.jpg)


thx
Sergio
Title: Re: Tube scream
Post by: pedalman on February 03, 2013, 12:55:37 AM
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 ?
Title: Re: Tube scream
Post by: gtangas on February 03, 2013, 02:04:33 AM
Quote from: pedalman on February 03, 2013, 12:55:37 AM
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?



Title: Re: Tube scream
Post by: pedalman on February 03, 2013, 02:41:46 AM
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

Title: Re: Tube scream
Post by: gtangas on February 03, 2013, 12:44:24 PM
I found this

(http://i775.photobucket.com/albums/yy38/gtangas/led_sil_zpsc609a41b.gif)

Title: Re: Tube scream
Post by: gtangas on February 03, 2013, 01:27:23 PM
Quote from: gtangas on February 03, 2013, 12:44:24 PM
I found this

(http://i775.photobucket.com/albums/yy38/gtangas/led_sil_zpsc609a41b.gif)

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



Title: Re: Tube scream
Post by: pedalman on February 04, 2013, 03:37:00 AM
i dont think thats right, square pad is a +
Title: Re: Tube scream
Post by: Stomptown on February 04, 2013, 07:35:21 AM
Quote from: hammerheadmusicman on January 29, 2013, 11:01:50 PM
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...
Title: Re: Tube scream
Post by: RobA on February 04, 2013, 07:44:27 AM
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
Title: Re: Tube scream
Post by: alanp on February 04, 2013, 07:49:00 AM
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.
Title: Re: Tube scream
Post by: gtangas on February 04, 2013, 10:16:40 AM
Quote from: RobA on February 04, 2013, 07:44:27 AM
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


Hi Rob

So i have to fix it again? When I start populating the board I soldered (d4 d5) with the flatted side of the led to the square pad.. After that I flip this setting...

According to yours explanations I have at the moment the leds soldered at the wrong way right ?

Thx
Title: Re: Tube scream
Post by: RobA on February 04, 2013, 02:21:10 PM
This is the Green Bean layout? If so, it doesn't matter which one you have going which way. As, long as the the two diodes are opposite each other, it is fine. Electrically, it doesn't matter which one is oriented which way.

Title: Re: Tube scream
Post by: gtangas on February 04, 2013, 02:25:50 PM
Yes it's the green bean layout.

Ok.... Uff....

I was thinking that I have to desolder those guys again!!