Messages

Guys.. need some help.

Received a request from a local player to create a custom volume pedal. His idea is to have a pedal with two or three foot switches that would allow him to adijust the volume Up, Down and possibly bypass. He later added maybe having leds that showed the current output level. So after talking to him what it looks like he wants is a pedal that will allow him to step the volume down at set increments (with 10 to 16 steps) and then step the volume back up to unity.

What I think I would need is an IC that would allow we to step up/down thru several resistor values to emulate turning a pot up / down. Not looking to boost the signal. From there I would imagine a second IC of the same type to control LEDs representing the current "level". Then wire up a standard bypass.

Any help would appreciated if anyone knows of a sample circuit or IC that would help get me started. I just started searching thru google, but figured someone here may already have an idea of where to start.

AllenM
MadTone

I started out with EZ Drummer and upgraded to EZ Drummer 2 and use it for all my song writing. Trying to decide on Midi Packs was always a chore until I discovered I could try out the Midi packs in the Search tab, you just have to check off a Show Web Shop MIDI and you have access to everything. Then I just select the library and run thru the MIdI pack and see how many of the grooves in the pack I like, if there is enough I add that this to my list to buy next time there is a sale.

Hope that helps.

AllenM

Shout out to Aion on the new 125b projects - love the layouts, features and the new documentation - the addition of the spreadsheet BOMs - ordered 10 PCBs and I cant wait to see what else you add to this series!

**also like that the BOM list currently available parts for items that are hard to find**

AllenM / MadTone fx

Link to project
https://aionelectronics.com/wp-content/uploads/2013/11/aion-cerulean-bb-documentation-v2.pdf

I had a friend request a build for a Prince Of Tone - after some research I decided to go with Aion's Cerulean board built as a King of Tone with a couple of the recommended mods. Based on the build document I included the Clipping Mod and changed the Drive pot to 250kB. For D1-4 I used 1n914, for D5-8 I also used 1n914 but asymmetrical and for DX1-2 I used 1n4148.

The pedal does work but I have a few questions / concerns - first is the volume control, I am having to turn to about 3-4 o'clock to get above what sounds like unity versus bypassed signal. This may be normal as I have never built this circuit before. My other concern is the Clipping Mod and Hard Clipping feature, with the pedal in gaged I am not noting any "sound" difference when changing the positions of either switch ( I used SPDT on/on). I figured I would at least have some signal / gain changed or even a "pop" when changing the settings awhile the pedal was active.

One concern is that using the same diodes for the two Clipping mods even though the second set is asymmetrical may not be noticeable and I need to use something more varied. But I was expecting to hear something change when engaging the Hard Clipping option.

Anyway.. any insights or suggestions would be appreciated. I will include some pics from the build process.

AllenM
Madtone

https://www.flickr.com/gp/17129774@N06/Z71P0m

https://www.flickr.com/gp/17129774@N06/1o0w94

https://www.flickr.com/gp/17129774@N06/26VcJG

Thanks for the update and looking forward to your new designs! Can't wait to see the top mount jack designs!!

AllenM
Madtone

Well the pedal needs to be on stage tonight so I replaced the booster with a JMK Beauty Booster and all is well. I may revisit this issue in the future if I decide to combine two circuits using charge pumps.

Again thanks for the recommendations and input.

AllenM

To gordo - I was wondering if I could run the boost from the Klon charge pump - I will have to look at that option.

I also thought about adding separate power jacks for the two devices but then that defeats the purpose of the all in one, plus most people I know use a daisy chains power cord  so it should end up the same.

The Klon plays fine with no whine at all - I only hear the whine when the Boost is active, otherwise the pedal is dead quite.

I did star ground and everything is separate. I replaced the chips in both units just to be sure and the whine remains.

In the long run I may just change out the Boost to another circuit that does not have a charge pump.

I have not considered the ground to the DC jack - currently it is tied to the Input jack with the rest of the ground connections.

Thanks for all the input and suggestions.

AllenM

Hey guys.. I put together a multi build http://www.madbeanpedals.com/forum/index.php?topic=27708.0 and I am getting a "whine" from the Boost section. After some testing I have verified that the boost circuit when removed from the multi build works normal. Upon further testing I noticed the whine would change pitch when touching the TC1044S on the boost and the Klon, so it appears I am getting some type of interference with them both in the same enclosure. Hoping there is a solution to possibly isolate the circuits from each other, otherwise it looks like I will need to replace the boost with a different circuit.

Here is the link to the tech support on the noise issue under the JMK section with a video link.

http://www.madbeanpedals.com/forum/index.php?topic=27698.0

Any help or suggestions appreciated.

AllenM

This is a custom one off by request. The layout is a Boss FA-1(Aion Prism) into a Klon(Aion Refractor) into a Wakizashi Boost (JMK). Things were pretty smooth over all and the enclosure had plenty of room to work in. I have some trouble shooting to do on the boost but nothing major.

The pedal sounds really nice in front of my 18 Watt clone. I set the Prism up as my clean drive and eq'd to taste, then the Refractor setup as my crunch and then finished it up with the boost set to push it up a notch for leads.

The finish was my standard wet sanded bare enclosure with labels.

I did get a new label maker and now I have 4 tape sizes to work with.

AllenM

Anyone seen a similar tap tempo kit available in the US?

http://uk-electronic.de/onlineshop/product_info.php?products_id=3099

I like that it is more compact than the current option from diystompboxes and possibly more budget friendly.

AllenM

So it turns out one of the ICs was bad. When I swapped them I lost the EQ and the volume started working. Removed them and installed the optional IC3 slot with a TL072 and everything is working!

Thanks to everyone one who chimed in!

AllenM

I update my last post. Tonight I will look into all my solder joints and also double check my ICs. I am now thinking the circuit is not amplifying the signal, I have used the FA-1 before and if normally has a lot of boost. The volume I have counter clockwise is not very loud and then fades as I turn clockwise.

AllenM

added a pic of the pot installation.. they should be good to go, hard to mess them up since they can only really go in one place. There are even little outlines on the PCB showing the pot outlines.

I have also added a picture of the component side, this was before I installed the ICs and Transistor.

Maybe my description of the problem is incorrect, I have volume counter clockwise and as I turn the pot clockwise the volume fades. Maybe my issue is the volume is not being amplified? So possibly an issue with the ICs or Transistor?

AllenM

Solder side along with the other pots, this why I am wondering what other part of the pedal could cause this action to happen.

AllenM

I just completed my build and was testing it before boxing it up noticed the volume control works in reverse. Trying to figure out what part of the build could cause that. The pot is PCB mount so I know it is correct.

Any ideas on what I should be looking at? I thought maybe the transistor as I had to substitute it, but the one I am using is only reversed orientation of the one specd.





Here is a link to the project page

https://aionelectronics.com/project/prism-boss-fa-1-fet-amp-pcb/

Just looking for som insight on what part or parts could cause the volume pot to act in reverse.

Thanks

AllenM