A Famous 1980's Vintage Chorus - With a Purple Dinosaur??? (AionFX Lithium)

Fingolfen

Well-known member
Build Rating
5.00 star(s)
I'd picked up the AionFX Lithium project when it was first released, but it sat in my build queue for a while. I finally got around to building it, and honestly I really like what he's done with the circuit...

AionFX Lithium - Purple Plesiosaurus - 01.jpg

The original Small Clone only had one knob (rate) and a depth switch (which provided two positions). The Lithium converts the depth switch into a knob allowing greater fine-tuning of the effect. The original also had no mix knob - the dry/wet signal mix was hardwired. This version of the pedal therefore allows even greater tuning of the signal than the original. There is also an internal toggle switch that allows you to alternate between the "vintage" and "modern" voicings of the pedal. Given I was only interested in the vintage version, I considered just hardwiring it, but in this case it was easy enough to have the option just in case I needed it later.

Most of the components for the build are fairly standard. I'm using my normal mix of 1% metal film resistors and WIMA/KEMET 5% tolerance film capacitors. The electrolytic capacitors are all Nichicon. As with most modulation effect pedals, the circuit is largely built around the BBD chip. The original used two different chips - the MN3007 or the SAD1024. The MN3007 is reasonably easy to find either in its original vintage form or the Xvive re-issue. The SAD1024 was used in a lot of early modulation effects and is sadly (pun intended) unobtanium at this point. Vintage units are rarely found and expensive if they are, and no one is making a re-issue chip at this point (Xvive I'm looking at you here!!!).

AionFX Lithium - Purple Plesiosaurus - 02.jpg

The Lithium project itself is designed to work on either the MN3007 or the MN3207 very similar to the most recent iteration of the Madbean Current Lover (an electric mistress clone which I built last year - and need to build more of!). Like the Madbean board, there are a pair of jumpers which need to be set depending on what chip you end up using. If you use the MN3207, however, there are several additional parts (two resistors, one tantalum capacitor, and a zener diode) which need to be added. I decided to go with the MN3007 because it was the most common BBD chip used on the originals.

The board is a little bit tight, but goes together straightforwardly. There is a 100K trimmer which is used to set the bias of the pedal. Like most chorus pedals, the bias can either be set by ear or oscilloscope. At this point I've just biased it by ear, but I may go back and tweak it just a little. As with all AionFX boards, there is a 3PDT daughter board with the reverse polarity diode and a few other components on it. I used ribbon cable to connect the two boards and aviation grade wiring for the rest of the hook up wire. The jack connections are all insulated with heat shrink tubing.

AionFX Lithium - Purple Plesiosaurus - 03.jpg

As the original pedal was purple, I figured the pedal needed a purple dinosaur as its mascot. Before you start running in terror - it isn't that purple dinosaur. We don't speak that purple dinosaur's name! Instead we have an awesome Purple Plesiosaurus. The dinosaur itself is licensed art from Adobe Stock that I've changed the colors around on to make it, well, purple! I ran the "Purple Plesiosaurus" text through a LOT of filters in Photoshop and Illustrator to mimic the style of Nirvana's Nevermind album - honestly I think that took almost as long as populating the PCB! I decided to go with the Tayda matte clear for the enclosure itself, and I really love the effect of the graphics directly on essentially a bare aluminum enclosure.

As for the sound of the pedal, with a little dialing in, you can definitely play Nirvana riffs to your heart's content (I tested it using my dino-built Noventa Jazzmaster - not a perfect replica of Kurt's guitar, but close enough for now!). Overall it's an amazing pedal which simultaneously captures the sound of the original, but with modifications to provide additional flexibility.

Original blog entry (with more preamble): https://steggostudios.blogspot.com/2024/04/a-famous-1980s-vintage-chorus-with.html
 
I'd picked up the AionFX Lithium project when it was first released, but it sat in my build queue for a while. I finally got around to building it, and honestly I really like what he's done with the circuit...

View attachment 72059

The original Small Clone only had one knob (rate) and a depth switch (which provided two positions). The Lithium converts the depth switch into a knob allowing greater fine-tuning of the effect. The original also had no mix knob - the dry/wet signal mix was hardwired. This version of the pedal therefore allows even greater tuning of the signal than the original. There is also an internal toggle switch that allows you to alternate between the "vintage" and "modern" voicings of the pedal. Given I was only interested in the vintage version, I considered just hardwiring it, but in this case it was easy enough to have the option just in case I needed it later.

Most of the components for the build are fairly standard. I'm using my normal mix of 1% metal film resistors and WIMA/KEMET 5% tolerance film capacitors. The electrolytic capacitors are all Nichicon. As with most modulation effect pedals, the circuit is largely built around the BBD chip. The original used two different chips - the MN3007 or the SAD1024. The MN3007 is reasonably easy to find either in its original vintage form or the Xvive re-issue. The SAD1024 was used in a lot of early modulation effects and is sadly (pun intended) unobtanium at this point. Vintage units are rarely found and expensive if they are, and no one is making a re-issue chip at this point (Xvive I'm looking at you here!!!).

View attachment 72061

The Lithium project itself is designed to work on either the MN3007 or the MN3207 very similar to the most recent iteration of the Madbean Current Lover (an electric mistress clone which I built last year - and need to build more of!). Like the Madbean board, there are a pair of jumpers which need to be set depending on what chip you end up using. If you use the MN3207, however, there are several additional parts (two resistors, one tantalum capacitor, and a zener diode) which need to be added. I decided to go with the MN3007 because it was the most common BBD chip used on the originals.

The board is a little bit tight, but goes together straightforwardly. There is a 100K trimmer which is used to set the bias of the pedal. Like most chorus pedals, the bias can either be set by ear or oscilloscope. At this point I've just biased it by ear, but I may go back and tweak it just a little. As with all AionFX boards, there is a 3PDT daughter board with the reverse polarity diode and a few other components on it. I used ribbon cable to connect the two boards and aviation grade wiring for the rest of the hook up wire. The jack connections are all insulated with heat shrink tubing.

View attachment 72062

As the original pedal was purple, I figured the pedal needed a purple dinosaur as its mascot. Before you start running in terror - it isn't that purple dinosaur. We don't speak that purple dinosaur's name! Instead we have an awesome Purple Plesiosaurus. The dinosaur itself is licensed art from Adobe Stock that I've changed the colors around on to make it, well, purple! I ran the "Purple Plesiosaurus" text through a LOT of filters in Photoshop and Illustrator to mimic the style of Nirvana's Nevermind album - honestly I think that took almost as long as populating the PCB! I decided to go with the Tayda matte clear for the enclosure itself, and I really love the effect of the graphics directly on essentially a bare aluminum enclosure.

As for the sound of the pedal, with a little dialing in, you can definitely play Nirvana riffs to your heart's content (I tested it using my dino-built Noventa Jazzmaster - not a perfect replica of Kurt's guitar, but close enough for now!). Overall it's an amazing pedal which simultaneously captures the sound of the original, but with modifications to provide additional flexibility.

Original blog entry (with more preamble): https://steggostudios.blogspot.com/2024/04/a-famous-1980s-vintage-chorus-with.html
Sweet build. I didn’t realize this version had additional controls added.
 
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