Easiest way to test different clipping diodes/transistors?

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ledvedder

ledvedder

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I have a few different diodes/transistors (MPSA06, 1N4733A, 2N5400),that I'd like to test in my 50 watt Chupacabra. Based on the attached layout, what would be the easiest way to test them, aside from desoldering the existing diodes and soldering the new ones in?
 

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Get a rotary switch and wire them all up to it. Then twist to change them. Determine which ones you like most and hard wire them in.
 
Desolder existing diodes and install sockets or connectors so you can easily swap parts in/out without soldering. You'll probably want to solder in place once you figure out what you like.

If you have 2 or 3 you like, you can always solder them in on a switch when you're all done.
 
This is what Nik sent in an email response, but I'm not understanding what he's describing.

"Say you want to experiment.

The easiest way is to hook it up.

Look at the current config - 1 side is grounded for the zeners on the board. Same with the MV, 1 lug is grounded.

The other side of the zeners, goes to the MV lug, thus they're actually across the MV pot.

So you can just wire from board - 0.22uf to the right leg of MV pot, zeners across to the ground lug of the MV pot

This is just to make it easy, without rewiring on the board, which can make it messy."
 
rstites":3o0h7sbe said:
Desolder existing diodes and install sockets or connectors so you can easily swap parts in/out without soldering. You'll probably want to solder in place once you figure out what you like.

What are these sockets or connectors?
 
ledvedder":1ia5566d said:
rstites":1ia5566d said:
Desolder existing diodes and install sockets or connectors so you can easily swap parts in/out without soldering. You'll probably want to solder in place once you figure out what you like.

What are these sockets or connectors?

I hate to sound like a dick, but if you’re asking that question, you probably shouldn’t be soldering inside an amp.

If you’ve never worked on an amp or at least pedals, I wouldn’t start here.
 
diocide":n906lsi3 said:
ledvedder":n906lsi3 said:
rstites":n906lsi3 said:
Desolder existing diodes and install sockets or connectors so you can easily swap parts in/out without soldering. You'll probably want to solder in place once you figure out what you like.

What are these sockets or connectors?

I hate to sound like a dick, but if you’re asking that question, you probably shouldn’t be soldering inside an amp.

If you’ve never worked on an amp or at least pedals, I wouldn’t start here.
Way to be a dick!

:D
 
diocide":2ib4eu76 said:
ledvedder":2ib4eu76 said:
rstites":2ib4eu76 said:
Desolder existing diodes and install sockets or connectors so you can easily swap parts in/out without soldering. You'll probably want to solder in place once you figure out what you like.

What are these sockets or connectors?

I hate to sound like a dick, but if you’re asking that question, you probably shouldn’t be soldering inside an amp.

If you’ve never worked on an amp or at least pedals, I wouldn’t start here.

I've worked on pedals and amps. But, I've always just replaced one component for another, or used alligator clips to test different component values. I never knew there were some sort of sockets or connectors that allow this, without soldering.
 
ledvedder":32cgtt3y said:
This is what Nik sent in an email response, but I'm not understanding what he's describing.

"Say you want to experiment.

The easiest way is to hook it up.

Look at the current config - 1 side is grounded for the zeners on the board. Same with the MV, 1 lug is grounded.

The other side of the zeners, goes to the MV lug, thus they're actually across the MV pot.

So you can just wire from board - 0.22uf to the right leg of MV pot, zeners across to the ground lug of the MV pot

This is just to make it easy, without rewiring on the board, which can make it messy."

I think what he is saying is just solder them to the easiest access points. One side goes to ground so pick your easiest ground point; the buss, the left lug on the MV, etc. The other side goes to the .22uF cap. Pick your easiest access to that; the middle lug of the Era switch, the right lug of the MV, etc. Of course when you do this the Era switch needs to be in the middle (OFF) position or you'll be putting it in parallel with the other diodes on the board (for whichever era the switch has selected).
 
But FWIW, I agree with psychodave. Use a rotary switch or the existing 3-way switch. I think you're going to want to go back and forth many times to make sure you can compare/contrast and get it right. Not everybody has dog ears like Dave.
 
Do I solder the black ends facing each other, or opposing?
 

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ledvedder":2392rjxe said:
Do I solder the black ends facing each other, or opposing?

Either. Try opposing. Don’t let the iron cook them. Twist together, hit with a little solder to join them and snip excess.
 
psychodave":6yfd0yc6 said:
ledvedder":6yfd0yc6 said:
Do I solder the black ends facing each other, or opposing?

Either. Try opposing. Don’t let the iron cook them. Twist together, hit with a little solder to join them and snip excess.
I was going to say it didn't matter but I wanted him to start to read the layout. The simple answer was right there. :thumbsup:

FWIW, you can use those alligator clips as heatsinks when you solder them, just clip the alligator between your solder point and the diode, closer to the diode.
 
I think what Nik meant was to adapt an IC socket in there. They are 8-pin. So maybe hang the other 2 off the board or cut them off.

You could mock it up in an old pedal box. Clamp it nice and close on the chassis and fly some leads in there with clips.

I wonder if parallel clippers would sound good? Like a wet dry blend?
 
I tested them using alligator clips between ground and the middle lug of the era switch. 2x5v zeners was too much clipping and to much volume drop.

2xMPSA06 transistors as well as 2x2N5400 transistors sounded better.

I've been reading about different variations using diodes, transistors, rectifiers, leds. Also, symmetrical vs asymmetrical. So many choices!
 
ledvedder":36jgjiba said:
rstites":36jgjiba said:
Desolder existing diodes and install sockets or connectors so you can easily swap parts in/out without soldering. You'll probably want to solder in place once you figure out what you like.

What are these sockets or connectors?

Here's a link: http://www.smallbear-electronics.mybigc ... -mill-max/

These are designed for circuit boards, but they'll work for your application. They're a SIP (single inline pin) type connector. You just break off what you need. They're just like a DIP socket for chips, but these work with caps, resistors, etc. Anything you want to experiment with without soldering, you can use these type of sockets.

However, given the amount of space in there, I'd probably just desolder the original set and use alligator clips to hold things on solder lugs while you try them out. If you try a bunch and don't want just one setting, then I'd go to a rotary switch as mentioned by someone else. Or, if you want just a couple of sounds, you can swap out a pot with a push-pull pot.......keep doing that and you'll end up with a Mesa-style front end where everything is pot and a switch! :)
 
ledvedder":3tia13r1 said:
I tested them using alligator clips between ground and the middle lug of the era switch. 2x5v zeners was too much clipping and to much volume drop.

2xMPSA06 transistors as well as 2x2N5400 transistors sounded better.

I've been reading about different variations using diodes, transistors, rectifiers, leds. Also, symmetrical vs asymmetrical. So many choices!

Think of the sum of everything. With 5 volt zeners you get a big volume drop, but now you can turn up the master and get the power tubes working more, which is a different sound. Also, you should adjust the gain pots to see if you like the tone at a different setting. Lastly, your gain pots have bright caps attached. You may like different values with different voltage zeners. You can’t just change zeners and hope for the best, you need to think of everything else in the circuit as well.
 
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