Conspiracy to Commit Electronics Megathread

[Chris Hass]

I watch to build (and add my own post-effect additons) a pedal that creates nice tubey saturation. Heavy on the tubey harmonics, but very low-gain.

Any suggestions for which C2C kit might be a good base for this?

 

[RomanS]

I watch to build (and add my own post-effect additons) a pedal that creates nice tubey saturation. Heavy on the tubey harmonics, but very low-gain.

Any suggestions for which C2C kit might be a good base for this?

Particle Accelerator!

 

[SamuelG]

And it's an easy mod to bypass the EQ if all you want is tube warmth/compression. You can also go a lower gain tube like a 12AT7 or even a 12AU7 if you want to stay completely clean.

 

[Chris Hass]

Particle Accelerator!

This is what I was leaning already, thank you for the reinforcement!

And it's an easy mod to bypass the EQ if all you want is tube warmth/compression. You can also go a lower gain tube like a 12AT7 or even a 12AU7 if you want to stay completely clean.

This may be the play. Any experience with the harmonics generated from one over the other at low-gain? It is so much easier to do at high gain!

 

[Tassieviking]

Does anyone know of a place that sells A250k dual gang 9mm potentiometers apart from Stompboxparts ?
I was going to order the pot from Stompboxparts but they wanted $95 US for postage for 12 little 9mm pots.
The new pedal has 1 x Dual gang A250k pot, 2 x B1M pots, 2 x B250k pots and 1 x B25k pot, all in 9mm like all C2CE builds.

If you live in the US you will be able to order them from Cusack Music / Stompbox Parts at :

9mm Potentiometer - Dual Gang

Top Quality Parts for Guitar Effects Pedals and DIY Music Devices. Knobs, Pots, Switches, Kits, LEDs, Enclosures, Jacks, Wire, Resistors, Capacitors, Semiconductors

stompboxparts.com

I would prefer to find a dual gang A250k pot but if I can't I will have to use a dual gang B250k pot instead for the XLR volume from Tayda.
Thanks guys and gals for any help
Mick

 

[sunbeast]

Does anyone know of a place that sells A250k dual gang 9mm potentiometers apart from Stompboxparts ?
I was going to order the pot from Stompboxparts but they wanted $95 for postage for 12 little 9mm pots.
The new pedal has 1 x Dual gang A250k pot, 2 x B1M pots, 2 x B250k pots and 1 x B25k pot, all in 9mm like all C2CE builds.

If you live in the US you will be able to order them from Cusack Music / Stompbox Parts at :

9mm Potentiometer - Dual Gang

Top Quality Parts for Guitar Effects Pedals and DIY Music Devices. Knobs, Pots, Switches, Kits, LEDs, Enclosures, Jacks, Wire, Resistors, Capacitors, Semiconductors

stompboxparts.com

I would prefer to find a dual gang A250k pot but if I can't I will have to use a dual gang B250k pot instead for the XLR volume from Tayda.
Thanks guys and gals for any help
Mick

A Google search showed me a few options (mostly US-based), here's one in Spain (though with knurled shaft): [Invalid or Expired Link Removed]

 

[Tassieviking]

It's supposed to rain where I am for the next 3 days, I wonder what I can do.

 

[davelowell2]

It's supposed to rain where I am for the next 3 days, I wonder what I can do.

Ok, spill it. What's the new circuit?

 

[wayshot]

Ok, spill it. What's the new circuit?

My curious mind started thinking "gotta figure out that circuit!" and took a closer look at the PCB pictures. Seems like a preamp designed as follows:

Input -> gain stage 1 -> tone stack -> gain control -> gain stage 2 -> cathodyne phase inverter. The two outputs split into 1) XLR volume control (dual pot) -> XLR output and 2) amp phase switch -> hi/lo signal level switch -> amp level control -> 1/4" output.

 

[Tassieviking]

I'm amazed no one has spotted the new art and drill files at the C2CE shop, they have been there for over a week now.

No transformer for the XLR

 

[Jared Houseman]

It's supposed to rain where I am for the next 3 days, I wonder what I can do.

This one has me stumped.

There's no room for a foot switch so it must be an always on preamp/ probably not very gainy

It looks like only one half of the input tube is being used, then it feeds directly to the tone stack.

There's also no room for a transformer and there's a dual gang pot for the XLR output, so I'm guessing the second tube is what is generating the differential signal for the XLR.

Nothing is coming to mind at the moment and I don't think it's copying any existing amps. Maybe this is more featured(3 band eq) , but still affordable (no xformer) sibling to the Steddi?

 

[Tassieviking]

I like this thread: Booya Tube Preamp /DI

This is my first rough trace of the PCB circuit, I always trace any new PCB i get.
There will most likely be mistakes on this schematic cause I did it in 1 hour tonight.

 

[Jared Houseman]

Well it definitely seems like an interesting different tube di approach. From skimming that thread, it seems like no one knows what it does or what it sounds like, not even the original designers.

Im needing another di to go on my pedalboard. I think I have enough information to start ordering parts...

 

[wayshot]

This is my first rough trace of the PCB circuit, I always trace any new PCB i get.
There will most likely be mistakes on this schematic cause I did it in 1 hour tonight.

Seems right to me.

Using a cathodyne phase inverter as a transformer-less balanced driver is an interesting design choice. However, I read something from Merlin "Valve Wizard" Blencowe about cathodyne inverters, taken from his Designing Hi-Fi Valve Preamps book:

Before finishing this section it is worth mentioning again that although the cathodyne is an exemplary phase inverter, it is unsuitable as a balanced line driver. When sending balanced signals down cables, the unbalanced source impedances must be equal if we want good rejection of interfering signals (that is the point of balanced signal transmission, after all). The cathodyne fails this criterion miserably; it would allow far more interference to couple to the anode-driven output, which would not be rejected by the CMRR of the receiving circuit at the far end of the cable. In other words, the cathodyne needs to be buffered from the outside world. This is easy enough to do, but it is perhaps disappointing that the cathodyne's two outputs idle at different DC voltages, so they cannot be directly coupled to a pair of identical cathode followers, say.

 

[Tassieviking]

Im needing another di to go on my pedalboard. I think I have enough information to start ordering parts...

Please note there are 4 Mallory type 150 capacitors on the PCB, 2 x 330nF 630V and 2 x 33nF 630V, Also the XLR volume pot is a Dual Gang A250k 9mm pot.
I order my stuff through Tayda and they don't have any dual A250k pots but they have a B250k dual pot and also some 1M dual pots that you could add resistors to to make it a A250K dual pot.
The Gain and Volume pots are marked B1M but I can see no reason why they should not be A1M pots, I thought audio pots should work better then linear pots in those places.

I can't imagine it will be too long before the PCB's appear in the C2CE shop now, hopefully soon now that I revealed what it is.
Cheers
Mick

My box was ordered 9 days ago from Tayda but it is still in the drill queue and then the paint and UV wait list after that, hey must be really swamped still with orders.

 

[Jeff Kissell]

and now for something completely different...

Is the Steddi Go DI basically a Vampire Slayer with a transformer and XLR? I love my VS and I actually really dig the sounds from my upright piezo pickup and from my P-bass thru this buffer, no real need for EQ. However I fly a bit and having a simple tube DI/buffer could be cool.
Follow up...
How hard would it be to build a Vampire Slayer with a transformer and balanced XLR out?

FWIW, I would not be the one to build either scenario, it's more of a "I can't read schematics and I don't have the soldering skills, so I'm asking those who can" type situation.

 

[wayshot]

Is the Steddi Go DI basically a Vampire Slayer with a transformer and XLR?

The circuits are different. The Vampire Slayer circuit is a parallel cathode follower as a near-unity-gain buffer. The Steddi Go consists of a gain stage into into a cathode follower with a volume control before the outputs. It can provide quite a lot of clean gain when the volume is turned up.

 

[Tassieviking]

and now for something completely different...

Is the Steddi Go DI basically a Vampire Slayer with a transformer and XLR? I love my VS and I actually really dig the sounds from my upright piezo pickup and from my P-bass thru this buffer, no real need for EQ. However I fly a bit and having a simple tube DI/buffer could be cool.
Follow up...
How hard would it be to build a Vampire Slayer with a transformer and balanced XLR out?

FWIW, I would not be the one to build either scenario, it's more of a "I can't read schematics and I don't have the soldering skills, so I'm asking those who can" type situation.

So what you want is a Vampire Slayer with a Pedalnetics DI after it ? The Pedalnetics is basically just a Sushi Box DI transformer in a box.
Pedalnetics has the DIM-Stick tiny DI or the newer MiniDI which is as small as you can get with whats inside the box.
I think that adding either of the Pedalnetics DI's will be the same as if Nathan designed a new Vampire Slayer with a XLR transformer in it.
Or you could get someone to build you a Vampire Slayer in a larger box and adding a Unagi E4305 DI transformer in the box for a DI output.
I would go for the separate Vampire Slayer and a Pedalnetics DI since it will be more versatile, you can add the DI to anything then.
EDIT: The newer MiniDI cost the same as buying the transformer itself to add to a Vampire Slayer, I know what I would get for sure.

DIm Stick - Pedalnetics

Experience the versatility of the DIm Stick with a transformer from Unagi Magnetics, making it perfect for any instrument you use. DIm Stick.

pedalnetics.com

MiniDI - Pedalnetics

(Ok, so as "mini" as far as we can get it with an actual transformer inside!) Our MiniDI is rocking a transformer from Unagi Magnetics, which is the house-brand from our friends over at SushiBoxFX! This is the same transformer they use in the tube-based Finally DI and the Venus Z. The frequency...

pedalnetics.com

Vampire Slayer PCB Set

This is a PCB set for building your own Vampire Slayer buffer. This is not a beginner project, so if you’ve never built a pedal before, then this isn’t for you. I’ve tried to make this as affordabl…

c2celectronics.com

Unagi Magnetics E4305 – D.I. Transformer

The E4305 from Unagi Magnetics is a D.I. transformer that was designed by Sushi Box FX for use in tube preamps, but it also works great as a passive direct box transformer or as a balanced output t…

c2celectronics.com

 

[Tassieviking]

This is the final trace I have done on the Tungsten Preamp, I had a few values wrong on the first trace I did that I posted above.
When I make up a schematic in KiCad I just copy and paste components that I have already placed and that is why I end up having to check component values after I have drawn the schematics.
I don't know what value resistor RADJ should be but it would help to adjust the High Voltage of the board to whatever it should be.
We will find out when the Build Docs comes out.
Cheers
Mick

 

[Tassieviking]

I got another parcel from Tayda yesterday, I installed everything for a dry run so I could see what it looks like.
I just have to do some soldering and wiring everything up, I also need to wait for the build doc to find out what the last "RADJ" resistor value is.
I decided to try the Pearl Grey box with some 1900H blue knobs since I haven't tried that colour before, I placed it next to 2 other pedals I haven't shown before.
I also got a Wah pedal box from Tayda and you can definitely fit a tube or two in there if you are careful, now I just have to find the tube wah schematic Nathan sent me and I can start experimenting.