Now the Fun Begins

[VenomBallistics]

Actually, I am veering off this idea. What I am finding with the different op amps is that at a point, that happens fairly early, the change in sound is negligible. Especially given the nature of distortion. As a guitar player, and musically, the difference is not significant. But I love learning.

Yup, you're learning.
these are the primary three takeaways of diode clipping where real differences are heard
the change from small signal diodes to LED is significant, as is the symmetrical and asymmetrical architectures.
I've found a good bit more mileage out of the bypass capacitors to be honest.

As a fellow wielder of the six stringed razor, I've come to understand these things quite well ... So much so that I don't really use them as directed anymore. I play tube fired heads. I have the magic these circuits aspire to offer in hot bottles of hollow state witchcraft.
In the next few weeks I hope to begin building a delay / boost pedal. all I want is a bigger signal to send to the 12AX7 in the front of the house and some time based witchery.
But that's me. while I encourage migration to tubes, I also encourage solid state exploration. Mistakes as solid state power levels are quite minor in consequence to the same in tube level power, so it is a great place to play until your error rate and bench protocols reach acceptable levels to host 300 - 600 volt projects.

 

[bertus]

Hello,

You could also try different colors of leds, as each color has its own curve:

Each color will give an other distortion sound.

You will also notice difference between Germanium , Silicium and Shottky diodes.

Bertus

 

[VenomBallistics]

Hello,

You could also try different colors of leds, as each color has its own curve:
View attachment 52573
Each color will give an other distortion sound.

You will also notice difference between Germanium , Silicium and Shottky diodes.

Bertus

Yes, I've seen this. Some are quite marked.
It's kinda worth it to cannibalize some Christmas tree strings. For indicator LEDs if nothing else.
But I think I might know what he's running into.
While different and audibly so, it's not so far removed that one holds significant value over the other. Our controls are rather course.
If you played MP3s through one of our amps, you'd quickly encounter frustration with our tone controls.
You might be happy with 8 - 10 db adjustment range over a flat response. Our response curves are radical as are our 16-24 db meat grinder tone stacks. We can make Peter Steel of Type O negative sound like Minie Ripperton. It is this vulgar range of adjustment to which we are accustomed that the relative subtlety seems lacking.

 

[bertus]

Hello,

ESP has a page about audio design with opamps:
https://sound-au.com/dwopa2.htm
Peter Vis has a page where you can calculate a baxendal tone control:
https://www.petervis.com/record_pla...dall-tone-control/circuit-and-calculator.html
And Anglefire has a page with all kinds of tone controls:
https://www.angelfire.com/sd/paulkemble/sound4e.html

Bertus

 

[VenomBallistics]

Elliott sound ... That's a blast from the past.
Save that link for sure. ESP was always good for a fresh take on concepts in a world of regurgitation.

 

[Audioguru]

The opamps shown recently are missing the very important two resistors at the - input. The resistors set the amount of gain. Without the resistors the gain is a few hundred thousand at low frequencies and with severe distortion.

 

[VenomBallistics]

The opamps shown recently are missing the very important two resistors at the - input. The resistors set the amount of gain. Without the resistors the gain is a few hundred thousand at low frequencies and with severe distortion.

Perhaps the examples shown were to illustrate clipping diode strategies to augment pre established knowledge.

 

[SparkyCal]

Thanks for all the info. I've done a lot of mixing and matching on my breadboard. Different LED colors, one LED and one regular diode, etc etc. I do hear a difference in some configurations, but unless you're looking for a precise sound in a recording environment, much of it will get washed out with the rest of the sounds you'll be playing to and with. However, as mentioned, I did appreciate it from a learning perspective. I've also watched many YouTube videos in which comparisons are made between configs- also, there is a pedal (I believe it is called the Walrus), that has the built in ability to switch between many diode configs. All very interesting/. I doubt the average guitar player would notice or appreciate the differences. After a chord or two, distortion is distortion.

Now...weighing what should be my nest project. Maybe something non musical for a change? There were suggestions made on another thread, but they may have been musical suggestions. I'll have to find the thread.

Maybe a 555 timer project? I've got plenty of the those and I think k I have 4017 chips too.

Thanks for hanging in with me during all my ideas and mistakes. Like I said, it's like a child going through the terrible twos lol

 

[SparkyCal]

The attached schematic looks interest g. What is a TIP127, as referenced in the schematic? Is it a type of transistor? I have a BC547 transitor, but not sure if I have a TIP127

 

[VenomBallistics]

The attached schematic looks interest g. What is a TIP127, as referenced in the schematic? Is it a type of transistor? I have a BC547 transitor, but not sure if I have a TIP127

Looks like a power transistor of some flavor.
It's function is to switch current to the siren once triggered by the high gain Darlington pair monitoring the piezo transducer

 

[Audioguru]

The datasheet for a TIP127 shows that it is a power PNP darlington transistor.
A BC547 is not a power transistor, is not PNP and is not a darlington.

The circuit is very old and was probably designed before a power Mosfet transistor was invented.

 

[SparkyCal]

The datasheet for a TIP127 shows that it is a power PNP darlington transistor.
A BC547 is not a power transistor, is not PNP and is not a darlington.

The circuit is very old and was probably designed before a power Mosfet transistor was invented.

Ok. Crossing it off the list

 

[SparkyCal]

Hmmm maybe I will stick to pedals for now and try the attached. Anyone know why there are grey circles throughout the schematic? I got this from EveryCircuit software

 

[VenomBallistics]

Never used said software, but I'll spitball at the circles being some kind of setpoint for the software

 

[VenomBallistics]

Don't be so easily dissuaded. It's kinda a cool circuit, even if it's old and AG would like to play games with me again ...
You have two BC 547s arranged in a Darlington pair.
One feeds into the other to create a very sensitive input stage.
When this gets tickled it will exceed the threshold of the TIP 127 which not only dumps current to the siren load, but also feeds current back to the input, effectively latching it into an on state until the power is disconnected.
Swap out parts as needed because that can easily be leveraged into a sort of tattle tale device to babysit for fault conditions as you screw around with things.
Do work that one out

 

[SparkyCal]

Hi VB and AG- I have already started the MXR Distortion pedal. I am actually interested in this one, as it is a popular pedal out there, and this one pro ports to be a clone.

 

[SparkyCal]

Don't be so easily dissuaded. It's kinda a cool circuit, even if it's old and AG would like to play games with me again ...
You have two BC 547s arranged in a Darlington pair.
One feeds into the other to create a very sensitive input stage.
When this gets tickled it will exceed the threshold of the TIP 127 which not only dumps current to the siren load, but also feeds current back to the input, effectively latching it into an on state until the power is disconnected.
Swap out parts as needed because that can easily be leveraged into a sort of tattle tale device to babysit for fault conditions as you screw around with things.
Do work that one out

The other issue is that I do not have a TIP127

 

[SparkyCal]

View attachment 52568
Yup, you're learning.
these are the primary three takeaways of diode clipping where real differences are heard
the change from small signal diodes to LED is significant, as is the symmetrical and asymmetrical architectures.
I've found a good bit more mileage out of the bypass capacitors to be honest.

As a fellow wielder of the six stringed razor, I've come to understand these things quite well ... So much so that I don't really use them as directed anymore. I play tube fired heads. I have the magic these circuits aspire to offer in hot bottles of hollow state witchcraft.
In the next few weeks I hope to begin building a delay / boost pedal. all I want is a bigger signal to send to the 12AX7 in the front of the house and some time based witchery.
But that's me. while I encourage migration to tubes, I also encourage solid state exploration. Mistakes as solid state power levels are quite minor in consequence to the same in tube level power, so it is a great place to play until your error rate and bench protocols reach acceptable levels to host 300 - 600 volt projects.

my stage gear consists of a Fender hot rod deluxe tube amp, and a suite of pedals. Fulton ocd distortion, boss chorus, boss digital delay and tuner. I have been there and back so many times with boss multi effects boards, Helix, Line 6 etc. I have learned that it is best to keep it simple and let the musIc talk.

 

[VenomBallistics]

The other issue is that I do not have a TIP127

I don't believe that to be a limiting factor to be honest.
Much the same as your use of a 4558, where a TL072 is holy writ, you may swap out parts.
You can hit DigiKey and use it's parametric parts search against specs of the parts called for, and have a list of suitable substitutes.

Funny thing is, for the vast overwhelming sea of parts out there, you would think we'd use more than the usual dozen or so that keep coming up since 1968. That kinda implies that you can get away with quite a lot with very little.

 

[VenomBallistics]

my stage gear consists of a Fender hot rod deluxe tube amp, and a suite of pedals. Fulton ocd distortion, boss chorus, boss digital delay and tuner. I have been there and back so many times with boss multi effects boards, Helix, Line 6 etc. I have learned that it is best to keep it simple and let the musIc talk.

I have a trainwreck clone and a Laney AOR.
Few Boss offerings like the od3 mt2 a chorus, and a delay. A random smattering of other things.
Honestly, I use very little if any drive from any of my distortions. Mainly, I use them as boosters and or extra tone control.
I really just let the amp be the instrument it was designed to be.
Though the pursuit of specialized pedal design remains intriguing.