Cloudlifter CL-1 Teardown + Custom PCB Build

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Bonfire

Member
Joined
Sep 5, 2023
Messages
8
Location
New England, USA
I wanted to share a four part video series on the Cloudlifter CL-1. Including a teardown and analysis of the components, recreating the circuit in KiCad, and ultimately producing a smaller version that fits into a Neutrik NA enclosure.

I've enjoyed reading the various threads on different designs of mic activator/preamps (all from people much smarter than me on this topic). I chose to deep dive on the CL-1 because I had one and I thought because of the general popularity that people might enjoy it. I posted the teardown video in a comment on another thread, but thought this might be worth its own post.

Feedback welcome! I'm sure people will find my desoldering blunders entertaining :) Enjoy!

 
Feedback welcome!
That's good entertainment, I didn't even know that this type of device is called an activator.

Anyway, your videos make me want to look at KiCAD again, I'm using EasyEDA at the moment, I'm actually satisfied, only the transfer of the circuit diagram to the PCB layout could be better. That seems to be well done in KiCAD.

You are very well equipped, I like the magnifying camera solution, how much does it cost? Are you happy with it?

The vacuum tool is also cool and of course the reflow oven, which I'm sure every DIYer has at home!;)

I can think of other applications for the Neutrik case, thanks for the tip.

The company that sells the Cloudlifter will certainly be grateful to you for all eternity. You also mention this in video 4, which is unfortunately the downside of such clone projects, especially when Gerber files are involved.

If this were a self-etching project, the risk of supporting industrial product piracy would be much lower.

I think your intentions are good but the consequences can be less good, you make it very easy for possible product pirates. They can simply get started with production thanks to your precise preparatory work.

Just my 2 cents
 
The company that sells the Cloudlifter will certainly be grateful to you for all eternity. You also mention this in video 4, which is unfortunately the downside of such clone projects, especially when Gerber files are involved.

If this were a self-etching project, the risk of supporting industrial product piracy would be much lower.

I think your intentions are good but the consequences can be less good, you make it very easy for possible product pirates. They can simply get started with production thanks to your precise preparatory work.
IMO there are better circuits to clone than CL1. What makes the CL1 sell is not its performance, it's its marketing, which is much harder to clone.
 
IMO there are better circuits to clone than CL1. What makes the CL1 sell is not its performance, it's its marketing, which is much harder to clone.
That is quite possible, I have no experience with these things as I have high gain mic preamps. Yes, it's true, most brands are made primarily through marketing, not just in the audio industry. (..and that usually costs money = "much harder to clone"). I was responsible for marketing and communication in the software sector for many years.

Edit: On the other hand, a very low price with comparable performance is also a very good selling point (due to no costs for development, preproduction and marketing). See all that China stuff and the rise of Alibaba, Temu, Aliexpress and so on...

Thanks to the OP's good preparatory work, a specialised company can generate a clone product within a very short time. This has already been done many times and is still happening.
 
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The derived Cloudifter schematic in the video shows just how similar the Cloudlifter is to the Alctron MA-1 (schematic attached)
That uses 4 x 2SK170s instead of the 2 x LS389 devices, but those devices are very similar - even noise wise.

The MA-1 is about the same size as the original Cloudlifter, but is extruded aluminium and not folded steel. ( It's built like a tank! )
It's also quite a lot cheaper than either the Cloudlifter or, I suspect, the device in the video...
(Typical price HERE --- or a bit more if you want it with the Alctron logo )

I see that the empty Neutrik case - with shipping - is more expensive than the complete Alctron device! 😮
 

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The derived Cloudifter schematic in the video shows just how similar the Cloudlifter is to the Alctron MA-1 (schematic attached)
That uses 4 x 2SK170s instead of the 2 x LS389 devices, but those devices are very similar - even noise wise.

The MA-1 is about the same size as the original Clouliffter, but is extruded aluminium and not folded steel. ( It's built like a tank! )
It's also quite a lot cheaper than either the Cloudlifter or, I suspect, the device in the video...
(Typical price HERE )
Yes, I would have been surprised if this product hadn't already served as "inspiration" several times.

Wow, that's really cheap, I discard my moral values and will order it immediately. 😅 😅
 
The MA-1 is about the same size as the original Clouliffter, but is extruded aluminium and not folded steel. ( It's built like a tank! )
It's also quite a lot cheaper than either the Cloudlifter or, I suspect, the device in the video...
(Typical price HERE --- or a bit more if you want it with the Alctron logo )

The unbranded 'activator' in the first of the links you provided has a very special distinction. Per the listed specs, it operates from Fantasy power:

Fantasy.png

While that's clearly a fantastic feature (!), imaginary power would be even better. Or so I imagine... o_O
 
There are a few threads here dealing with this type of products.
https://groupdiy.com/threads/cloudlifter-cl-1repair.78404/https://groupdiy.com/threads/microphone-boosters.75923/
In normal conditions, these things are at best neutral, but generally detrimental to noise. That's because it is almost impossible, within the constraints of P48 phantom power, to achieve better than ca. -125dBu EIN, when any half-decent mic pre is capable of about -127-128.
However, there are conditions where such a product can bring betterment. the most common case is when the connection between mic and preamp is polluted with RFI/EMI, then the increased level helps repelling noise.
Another case is when the mic impedance is significantly higher than the nominal 150/200 ohm standard. It happened to me, and that's why I decided to investigate these things.
But in most cases, like their ubiquitous use in conjunction with an SM7, it's just a matter of being louder, which is the most common lure in audio.
 
Cloudlifter_Schematic.jpg

Screen captured the end of part 2...

For a 200Ω source it looks to have a differential input LPF of about 884 kHz.
Is EMI the cloud being lifted?
WRT avoiding rectification the choice of a FET input seems wise.

"Fantasy" power is auto-corrected "phantom" and shows the complete lack of any proofreading.
 
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I've emailed back and forth with the person who designed and builds cloudlifter and he has re-ribboned some very fragile vintage mics of mine with RCA-spec ribbons. He's a good dude. He's doing it for the right reasons, and the CL is application specific. He's an incredible source of knowledge about ribbon mics among other things. I say, kudos to him for building a useful tool for ribbon mic owners, recording studios and definitely for broadcast. If you need it great, if you don't, great. And my 2c is that if you're going to clone it, it might be nice to reach out to him out of courtesy and have a conversation. The internet makes it feel like there aren't people behind products and companies. You might find he is amiable and supportive of your efforts, or he might direct you to pursue something more original if he isn't comfortable with it. That is def intersting info about 48V not being capable of high-enough headroom in a mic activator role.
 
I've emailed back and forth with the person who designed and builds cloudlifter and he has re-ribboned some very fragile vintage mics of mine with RCA-spec ribbons. He's a good dude. He's doing it for the right reasons, and the CL is application specific. He's an incredible source of knowledge about ribbon mics among other things. I say, kudos to him for building a useful tool for ribbon mic owners, recording studios and definitely for broadcast. If you need it great, if you don't, great. And my 2c is that if you're going to clone it, it might be nice to reach out to him out of courtesy and have a conversation. The internet makes it feel like there aren't people behind products and companies. You might find he is amiable and supportive of your efforts, or he might direct you to pursue something more original if he isn't comfortable with it. That is def intersting info about 48V not being capable of high-enough headroom in a mic activator role.
He has done an excellent job on a handful of vintage ribbons for me as well. He is also a very nice guy.

I have a handful of these types of devices in my studio and I have never found a time it’s actually worked great. I guess I have mic pres that don’t need the help from these devices or I just haven’t found the right application yet. Too me they are a neat idea just not useful for me (as of yet).
 
He has done an excellent job on a handful of vintage ribbons for me as well. He is also a very nice guy.

I have a handful of these types of devices in my studio and I have never found a time it’s actually worked great. I guess I have mic pres that don’t need the help from these devices or I just haven’t found the right application yet. Too me they are a neat idea just not useful for me (as of yet).

I have one of the dual-channel Cloudlifters (CL-2) and also several TritonAudio Fetheads here.

While I get what you're saying, I do find that they make certain mics (ribbons and moving coil dynamics) sound a bit different from how they would otherwise sound (including slightly more high end extension, so a bit closer to the sound I'd normally associate with a condenser mic, while retaining some of the character of the 'original' mic). As part of that, they open up opportunities to use those mics in situations where I would not otherwise use them.

If you never find yourself wanting to use a mic in a situation where it is struggling (or if your response to that situation is always to swap the mic out - and your mic locker is replete enough to support that) I can see how you might think these devices redundant.

Even so, there's a smoothness to some ribbons that works exceptionally well on certain instruments and voices - providing the attendant low output and high end rolloff don't 'spoil the party'. The RPQ from AEA has curves and extended gain to surmount that - but the cloudlifter/fethead can get a comparable result with a number of other pres that aren't quite so well adapted to the task.
 
The derived Cloudifter schematic in the video shows just how similar the Cloudlifter is to the Alctron MA-1 (schematic attached)
That uses 4 x 2SK170s instead of the 2 x LS389 devices, but those devices are very similar - even noise wise.
Linear Systems clearly mentions them as identical, except the dual LSK389 has better thermal tracking, which results in less offset drift.
It may matter if the "actuator" is connected to a preamp with an input xfmr, because this offset may result in some DC current in the xfmr winding.
I would think in most instances it would be unconsequential.
2SK170 is very common, contrary to the LSK389, which commands a big premium.
I've considered re-laying mic MicBooster PCB for more options (TH, SMD and singles).
 
Interesting that the circuit is basically a voltage-to-current converter so the actual gain you see will depend on the preamp's input impedance (and cable capacitance). It also looks (from the LSK389C datasheet) that each output leg wil be pulling 5mA or so, so it's quite demanding on the phantom fantasy power.
 
You are very well equipped, I like the magnifying camera solution, how much does it cost? Are you happy with it?
I saw that you found it (Andonstar AD407). I paid a little under $200 for it when I bought it a few years ago. I'm really happy with it for soldering and inspecting my work. It's a solid hobbyist tool, but you won't start a biotech company in your garage with it :)

I don't use the stand that it came with. I made a mount for it and I use a microphone arm to hold it above my solder station. I like that I can get it far enough away from what I'm working on to get my iron and hot air in there without being jammed up against the lens. Being on a microphone arm is also nice because I can easily swing it out of the way when I'm not using it.

The only downside to eliminating the stand is that you lose the LED lamps that are attached to it. I bought a ring light that I attach to the microscope directly. Very happy with this setup. I never planned to use it for recording videos, but that has worked out really well.

The company that sells the Cloudlifter will certainly be grateful to you for all eternity. You also mention this in video 4, which is unfortunately the downside of such clone projects, especially when Gerber files are involved.

If this were a self-etching project, the risk of supporting industrial product piracy would be much lower.

I think your intentions are good but the consequences can be less good, you make it very easy for possible product pirates. They can simply get started with production thanks to your precise preparatory work.
I get what you are saying. I was a bit conflicted about this, which is why I put that disclaimer in video 4 @ 1:08. Some thoughts on this topic:
  • There is so much competition in this space at a variety of price points (some being MUCH cheaper than the CL1). It's hard for me to imagine a new entrant in this space having any success. It's hard to beat cloud being the name brand that is used as the standard.
  • The build that I did was surprisingly expensive and a lot of effort to assemble. I probably spent like $50-70 (not including labor). Someone trying to set up a small operation would probably find that it isn't worth their time. Someone who is already set up to do this sort of thing could easily reproduce this board even without my design files.
  • I suspect the market for mic activators is probably going to drop off a cliff in the near future (from the perspective of youtubers and streamers etc). Mainly because budget interfaces have become so good that a mic activator isn't really needed anymore (the 4th gen scarlet line excluding the Solo for example). A SM7B + 4th gen scarlet 2i2 is cheaper than a SM7B + scarlet solo + cloudlifter. Also, the SM7dB that was recently released already has a Cloud preamp in it.
Anyway, I hope I didn't upset Cloud with this project. That wasn't my intent. I gave them credit for the build quality being great. Hats off to all their success. If the choice is between buying versus building one, buying a real cloudlifter is more cost effective IMO. Building is more of a passion type thing. That's my 2 cents.

Thanks for the kind words about the video series. Super cool to see conversation being sparked about it.
 
Mainly because budget interfaces have become so good that a mic activator isn't really needed anymore

I was thinking that very same thing.

Question: I presume these devices boost both noise and signal, and, perhaps, introduce some noise of their own - n'est ce pas?

Thanks - James / K8JHR
 
The build that I did was surprisingly expensive and a lot of effort to assemble. I probably spent like $50-70 (not including labor).

... For a one-off. How huge must the overhead on the real thing be, considering bulk discounts on components, and that the thing retails well north of $100?
 
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