So far so good! I'm thinking about placing the speed adj pots on the front.
I do have the speed adjust trims up a bit - wasn't sure what frequency to dial it to so I just set it fast for a fun sample.
As for the 3rd harmonic, I'm not quite hearing it but I do know the treble section was more dominant for that part due to the position of the balance pot for much of the demo.
Perhaps it can be explained by the signal source. I was using a Pro-One clone. At first it's just a single oscillator quickly sampled via mono, stereo and then super stereo through the rest of the demo. Then came white noise and finally two oscillators. The two slightly detuned oscillators could definitely cause some strange or rather interesting harmonic oscillation.
I need to do a demo with an organ as a sound source - that'll show it's true colors as a Leslie. That's coming next.
Since the CLS-22 began as a DIY project according to the original designer I will respectfully share my files with the DIY community after I polish things up.
I will also be selling my spare CLS-2022 PCBs, adapter boards for other BBDs (when ready) and likely some specialized parts on the side like the two TDA1074A with heatsinks pre-glued and maybe a pre-wired rotary switch solution.
The next thing I may do is design a custom rack model to be fabricated and also the front panel artwork. I will offer these as well.
I have to tidy up some details of my schematic and will share the fabrication gerbers, bill-of-material spreadsheet and also my interactive build guide.
A little update. I've secured a small supply of the TDA1074A chips which is great - enough to get a dozen or so of these built.
I've been picking away and verifying things as well as including possible mods.
Now, I've been running a virtual B3 through this thing and let me say... this thing is spot on for a Leslie!
If anyone would like to recommend some other mods I'd be happy to entertain the possibilities.
I've been picking away and verifying things as well as including possible mods.
- Modifying the 22 to use a 4-throw Basis rotary switch. Since the mini rotaries I have are 4-throw I've decided to sort out the necessary mods to have it function similar to the CLS-222 with an extra Stereo option before "Super Stereo".
- Effect switch for buffer bypass - again like the 222. I wanted to simply snub in a true-bypass switch but isn't possible with the stereo split. So instead of working out my own buffer circuits I've simply borrowed from the 222 circuit. Right now it's on vero-board but will be included in the next revision of the PCB. This circuit uses the other half of the opamp as a buffer for mixed channels so I'll also have a mono output!
- Using MN3007/MN3207 - looks like my source for the TDA1022 chips went up dramatically. In retaliation I'm going to modify the circuit to use V3207/MN3207 & MN3007 BBDs. For this I will have to modify the comparator circuits to double the frequency, include a buffer for sharper pulses, bring the BBD's reference voltage to 14/15th VDD with a simple resistor swap and include a 9-volt regulators (optional) for the 3207 chips. The signal will likely have to be brought down a little for the 9-volt BBDs.
Now, I've been running a virtual B3 through this thing and let me say... this thing is spot on for a Leslie!
If anyone would like to recommend some other mods I'd be happy to entertain the possibilities.
I'll put up another video of the circuit board over the weekend to demo the mods and some B3 action. When finalized I'll do a complete demo and use my friend who plays keys professionally.
Anyone could do what I'm doing. I've just had years of practice! I really do enjoy the learning experience of it all, plus with better understanding I can see why the author kept their ambition to develop the circuit over a year - it's brilliant!
A note about a previous question I had on why 4 comparator ICs were in the original design. After reviewing the datasheets once more I've realized that the channels in the CA3290 have common gates for the mosfets which may induce glitching between the channels. Additionally, while the LM339 is a quad version of the LM393, the 339 also has common connections between the 4 channels while the 393 does not show this between the 2. So out of curiosity I'm going to place a few jumpers to see if I can omit two of the comparator chips. I may also try this with the CD4013 chips as I believe the channels are isolated other than the supply rails. It would be nice to be able to omit some redundancy especially since I'm adding buffer chips to drive the alternative BBDs.
The more you know.
Had an afterthought to share the "mods" that I had described for the Effect switch and mixed Mono output.
Also, here's one for the rotary. I understand some folks have units with bad rotaries so a 4-throw mini can be wired and used like I had done though you'd have to widen the front-panel hole due to the wider bushing. Here's some notes on the mod to make it like the 222. While the photo was pre-mod, I wired the 3rd throw to the open pads and soldered the extra resistors on the underside.
This will all be in my final document which is more-or-less a journal of my progress. Figured I'd share these bits to help folks with original CLS-22 units.
Also, here's one for the rotary. I understand some folks have units with bad rotaries so a 4-throw mini can be wired and used like I had done though you'd have to widen the front-panel hole due to the wider bushing. Here's some notes on the mod to make it like the 222. While the photo was pre-mod, I wired the 3rd throw to the open pads and soldered the extra resistors on the underside.
This will all be in my final document which is more-or-less a journal of my progress. Figured I'd share these bits to help folks with original CLS-22 units.
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Hey, BassAmp. Sorry I had missed your reply. The forum seems to have disabled my account and I had to reverify my email to respond here. I had pulled up this thread today for another reason and caught your post.
I wasn't sure if anyone was still interested!
I had put the brakes on updating the circuit for modern parts as other projects popped up (story of my life).
I also wanted to do a custom rack enclosure but hadn't had time to finish it up.
I did however fix some small bugs (one bad track & mislabeled a couple terminals for the LEDs) and can say it's 100% ready for others to build. However the current asking price for the TDA1022 is absolutely insane. They are over 4 times more expensive than they were when I had done this project.
That all said, I'll share the gerber files within the next few days.
I do have spare boards from the first run and I'd be more than happy to ship it out to anyone interested if they don't want to put in their own PCB order. I'll throw in the pair of TDA1074A chips with the heatsinks as well. Best to email me if interested to discuss price & shipping costs.
Thanks for taking interest and keeping up with the project. I'll be back soon.
I wasn't sure if anyone was still interested!
I had put the brakes on updating the circuit for modern parts as other projects popped up (story of my life).
I also wanted to do a custom rack enclosure but hadn't had time to finish it up.
I did however fix some small bugs (one bad track & mislabeled a couple terminals for the LEDs) and can say it's 100% ready for others to build. However the current asking price for the TDA1022 is absolutely insane. They are over 4 times more expensive than they were when I had done this project.
That all said, I'll share the gerber files within the next few days.
I do have spare boards from the first run and I'd be more than happy to ship it out to anyone interested if they don't want to put in their own PCB order. I'll throw in the pair of TDA1074A chips with the heatsinks as well. Best to email me if interested to discuss price & shipping costs.
Thanks for taking interest and keeping up with the project. I'll be back soon.
No worries! Really glad to see that you're back. I've had this in the back of my mind since you posted your video. I need to re-read the thread but I seem to recall you were going to use try replacing the TDA1022 with an MN3007 or something like that. Did that never materialize? I just did a little looking around and you're right, these things are pricey. This would be quite an expensive undertaking. Looking forward to the updates.
Thanks!
As for my original CLS-22 clone, here's what I was working on for the DIY community. You'll find links for the gerber files, interactive build guide, BOM spreadsheet with links to my personal sources and of course the massive schematic. This was more-or-less ready to share, I guess I was just waiting for the bell 
With great appreciation & admiration to the original author for educating us on his classic design, I present the open-source CLS-22 clone project.
CLS-2022 V1.0 Document & Build Info
For anyone wanting to entertain this build as it sits, please do feel free to ask any questions.
I will return with a better demo using organ sounds rather than a free running mono synth and at the proper leslie speeds.
BassAmp,
Looking back on my files I do see where I had left off. What's best for updating this project would be for me to peruse my adapter board idea where MN3007 can be used in place of nearly any TDA1022 based circuit with only minimum modification to the existing circuit. While I'm currently in the middle of a couple intensive DIY projects I have every intention of revisiting this one for the MN3007 solution. You'll be the first to know when that's good to go (perhaps within the next few months).
Be back soon.
Take care!
With great appreciation & admiration to the original author for educating us on his classic design, I present the open-source CLS-22 clone project.
CLS-2022 V1.0 Document & Build Info
For anyone wanting to entertain this build as it sits, please do feel free to ask any questions.
I will return with a better demo using organ sounds rather than a free running mono synth and at the proper leslie speeds.
BassAmp,
Looking back on my files I do see where I had left off. What's best for updating this project would be for me to peruse my adapter board idea where MN3007 can be used in place of nearly any TDA1022 based circuit with only minimum modification to the existing circuit. While I'm currently in the middle of a couple intensive DIY projects I have every intention of revisiting this one for the MN3007 solution. You'll be the first to know when that's good to go (perhaps within the next few months).
Be back soon.
Take care!
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OK guys so can someone explain to me the basic operation of this unit?
So signal goes in and gets split into high and low frequencies much like in an actual Leslie, then it gets sent into two BBD lines per channel, one being 180 degrees out of phase with the other, then it goes into the TDA1074 chip for the amplitude modulation, but there are two in series per channel am I correct? Why is the second one seems to be controlled by an LFO 90 degrees out of phase from the first one though?
Then a portion of one channel is being fed into the output of the other channel and vice versa, am I correct?
So signal goes in and gets split into high and low frequencies much like in an actual Leslie, then it gets sent into two BBD lines per channel, one being 180 degrees out of phase with the other, then it goes into the TDA1074 chip for the amplitude modulation, but there are two in series per channel am I correct? Why is the second one seems to be controlled by an LFO 90 degrees out of phase from the first one though?
Then a portion of one channel is being fed into the output of the other channel and vice versa, am I correct?