Stuff you wanted to know but were afraid to ask

[Chuck D. Bones]

Not mV, Volts. Vf for 1N4148 is around 0.7V = 700mV. Also, the Vf you read in a datasheet or measure with a meter will not be the same as the clipping voltage, but it will be in the ballpark. The dB difference is 20*LOG(Vf1/Vf2) where LOG is base 10. In this example, Vf1 = 1.8V and Vf2 = 0.7V. Therefore, the dB increase going from 1N4148s to red LEDs is approx 8dB, which will be noticeably louder. The tone will be different too because the knee of the I/V curves is different.

 

[cdwillis]

Ok. I have another question then. Bare in mind I haven't had a math class in a long long time. What do you mean by base 10 in that equation? If I see base 10 I assume it means a number system based on tens, vs something like binary based on two values or an octal system based on eight.

 

[Chuck D. Bones]

Do you know what LOG means? If not, look it up. There are three common LOG bases. "Natural logarithms" are base e. If you see LN(x) in an equation, it's a natural logarithm. dB uses base 10 logarithms,represented as LOG(x). Octaves use base 2 logarithms, represented as LOG2(x). They are all the same function, just different scale factors.

Log is the inverse of exponential, if that helps. 10 squared is 100. LOG(100) = 2.

 

[cdwillis]

Ok, like a logarithmic pot versus a linear. I knew there were a couple different logarithmic tapers used in pots from watching Psionic Audio amplifier videos. At first I thought maybe you meant 20^10 (twenty to the tenth power). That's really helpful. I was trying to figure out if the LEDs would let enough signal through to use a full TMB EQ without killing the signal. Gotta take into consideration the minimum gain in the noninverting op amp gain stage beforehand.

 

[Chuck D. Bones]

You will probably want some make-up gain after the EQ. Typical loss in a Fender/Marshall TMB is 10 to 20 dB, depending on settings. Or you could stack LEDs or diodes to get a higher clipping voltage.

 

[Harry Klippton]

What's a harmonic percolator supposed to sound like?
My only experience with playing one was a pedal my friend had from a small builder. I thought it sounded awful and made everything sound only worse.

 

[cdwillis]

That's pretty much what they sound like

I have a friend that's built several. They sound somewhere between a fuzz and a distortion, probably because of the clipping diodes at the end. I keep saying I'm going to build one, but it keeps getting put on the back burner.

 

[eh là bas ma]

What is the effect used on bass at the beggining of this song (1996) ? enveloppe filters ? Which one ?

 

[Harry Klippton]

What does it mean on pedalpcb schematics when resistors and capacitors have their opposite ends labeled 1 and 2?
For example

 

[benny_profane]

their opposite ends labeled 1 and 2

I believe it has to do with identifying the pads of the package, which will have an impact on the silkscreen. You can move the refdes/values on the board view if the orientation isn't correct for your layout.

 

[Chuck D. Bones]

The board routing software needs to have pin numbers assigned to every component. Pin numbers on R's & C's don't need to be visible on the schematic.

 

[Robert]

What does it mean on pedalpcb schematics when resistors and capacitors have their opposite ends labeled 1 and 2?

I use the numbers for reference when tracing a PCB. It makes things much easier when I can look at the schematic and know without a doubt which end of a component a particular trace connects to. 1 = Bottom or Left end of a component, 2 = Top or Right end of a component, depending on whether they are oriented horizontally or vertically. (this is just a mental note that I use, not some set standard that anyone else follows)

They mean nothing as far as the finished PCB is concerned. Sometimes I remove them from the final schematic but it's a bit of a manual process since I can't just "Hide all" because we DO want the pin numbers visible for ICs, potentiometers, transistors, and switches.

 

[Harry Klippton]

Thanks @benny_profane @Chuck D. Bones @Robert

 

[UtilityBeltFX]

How do you guys solder your LED legs (On/Off LEDs, not clipping LEDs)? I'm not talking about when they drop in perfectly to the pcb, but when the legs are just dangling there. I see some people heat-shrink each individual leg to the wires. I haven't quite figured that out...

 

[jjjimi84]

Ask @jjjimi84 what to do with extra pedals.

Give them away to someone who will love them, I do this to try and fill up the karma slush fund.

He's gonna say build a spare room with shelves to store them!

If it was up to me my basement would be completed and be an entire giant room to record and build and store pedals. I am out of room again and i just put up more shelving.

I haven't listened to a lot of Zappa but to me it's the musical equivalent of an inside joke that I'm not in on. It seems like, from my uninformed perspective, that at least part of the appeal of his work is the relative complexity, which is a huge turnoff, and there's an undercurrent of comedy or cleverness that I don't appreciate either

@Harry Klippton just explaining shit in a way i like.

Robert Plant could've been replaced with a keyboard and I'd've been fine with that.

Queue the cat piano, putting that on the list.

How do you guys solder your LED legs (On/Off LEDs, not clipping LEDs)? I'm not talking about when they drop in perfectly to the pcb, but when the legs are just dangling there. I see some people heat-shrink each individual leg to the wires. I haven't quite figured that out...

I solder a wire as close to the led on the cathode and then bend the anode out a bit and solder it a bit further out. Once i stuff them in a bezel they never touch

 

[KR Sound]

How do you guys solder your LED legs (On/Off LEDs, not clipping LEDs)? I'm not talking about when they drop in perfectly to the pcb, but when the legs are just dangling there. I see some people heat-shrink each individual leg to the wires. I haven't quite figured that out...

I strip the wire about an inch and wrap it around the legs a couple times, solder it on, trim the excess lead of the LED, then heat shrink them.

 

[Chuck D. Bones]

I mount my 5mm LEDs in a chrome bezel. If the LED leads can be more-or-less straight from the board to the bezel, then I omit the plastic LED retainer. If the LED is to be mounted nowhere near the LED pads on the board, then I put the plastic retainer on the LED, then lap-solder flex leads to the LED leads and then put heat shrink over the solder joints for insulation and strain relief. I use different color wires so I don't lose track of the polarity. I use clear heat shrink, first over each wire and then another piece over both wires.

 

[andare]

I strip the wire about an inch and wrap it around the legs a couple times, solder it on, trim the excess lead of the LED, then heat shrink them.

View attachment 44856

That's what I do also but mine look horrible. I haven't found a clean way to splice the CLR to the LED leg. Not as easy as twisting them together as the leads are rather sturdy.

 

[Feral Feline]

What is the effect used on bass at the beggining of this song (1996) ? enveloppe filters ? Which one ?

Sounded like EHX Bassballs to me.

Thanks for the vid, haven't listened to Skunk Anansie in ages.


PS: @eh là bas ma — I forgot to mention you can get the Bassballs in the PPCB shop, “Lowballer”

 

[KR Sound]

That's what I do also but mine look horrible. I haven't found a clean way to splice the CLR to the LED leg. Not as easy as twisting them together as the leads are rather sturdy.

I’ll take some pics of how I do it. I’m out of town now, but can do it this weekend.