OPEN SOURCE DIY Mic Project - ORS 87 - Stripped Down u87

[Wordsushi]

*UPDATE
This is an OPEN SOURCE project. Feel free to experiment and comment with your questions, ideas and build experiences.

What initially started as another boring thread about the possibility of modding a Chinese-made u87 clone circuit mic turned into a banger when @OneRoomStudio posted an idea for a stripped down u87, made up of just 21 components on perfboard. He had eliminated the extraneous pad, filter and pattern portions of the vintage u87i from the schematic and the end result is something really raw and beautiful, and quite a cool little project, which I have dubbed the ORS 87 in recognition of OneRoomStudio's humble contribution.

So, I've decided to edit and update this thread and this first post to reflect the change in direction that this thread took.

The ORS 87 stuff begins on Page 3.
https://groupdiy.com/threads/aliexpress-faux-tlm-193-is-a-u87.86814/post-1137386

And if you do decide to build this project, or any other project you find on GroupDIY, please consider making a small donation to GroupDIY.com in order to help support this one-of-a-kind platform for DIY.

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So, the fake TLM-103 on Ali has a bastardized 87ai circuit, BUT is this fake TLM-193, as seen above, also, let's just call it, an 87ai variant?
The Ali/Ari TLM-103 I have with an Arienne k87 sounds far, far better on me than a real 103 and is quiet AF.
Kinda find myself wondering what a fake TLM-87193 with the Ari 87 capsule I have coming soon would sound like together. Hmmmm.
Or an Ali u87ai, you know that total imposter looking one that people say sounds surprisingly closer than you'd think. Ruud, I'm looking at you.
Someone please talk me out of it.
I'm helpless against my microphone addiction.

 

[SparkleBear]

I'm helpless against my microphone addiction

That makes two of us bubb.

I find that body to be way more attractive than the fake u87 with the fake switches. The darker tone and no fake switches are slick. I want one… ugh. I bet a trafo swap would do good too.

Curious what Ruud has to say hehe

 

[RuudNL]

I see a transformer inside, so it can never be a TLM! (TransformerLess Microphone .)
I also see a 180 pF capacitor that indicates a de-emphasis filter.

@Wordsushi: I have modified several 'Ali' U87ai's.
Rebiased the FET (all microphones seem to have a 7.5K source resistor!), increased the value of the 47 nF capacitor to 100 nF for a better LF response and tuned the 180 pF (original 160 pF) capacitor to obtain te desired high-end. After these minimal modifications, the 'Ali' U87ai sounds identical to the 'real thing'...
So far I always kept the original capsules.

 

[LevinGuitar]

Aren't those circuits an emitter follower like the rest of the chinese mics? What ratio is the transformer?

 

[living sounds]

This looks like an actual U87 circuit. The fake 103 has a hybrid circuit, TLM103 for the DC converter part and otherwise U87 circuit with a few errors/simplifications.

 

[svyet]

Loving the product features: stereo, ABS plastic, noise-cancelling hahah

I saw this and another "193" with a Neuma badge.

As far as talking you out of it, just ask yourself if you need another 87. Or perhaps this is filling a gap given the circuitry? I guess if it really adds something by way of looks and the existing circuitry, you can always sell off some of what you have. I'm sure you'd be able to achieve that pretty quickly through your platform. This definitely doesn't help, but as an occasional viewer, I certainly wouldn't mind seeing a review of this haha...but for $200 it's not my place to suggest one way or the other. Ruud's suggestions are englightening though by way of economics..it certainly has me tempted if/when I were looking for an 87. I have a real 193 with no need for other flavors at the moment.

 

[Wordsushi]

“Building a better mousetrap” implies that one already has available mousetraps, but instead better speaks to the innate human curiosity that makes us want to see “what would happen if…?”
And that’s where I am right now. I really don’t need another 87 style mic, but creating my little Frankenstein army of them, all with their slightly different flavors of 87-ishness, has become a bit of an obsession.
Also, a fairly major consideration to explore the dark underbelly of possibly turning the Ali fakes into competent professional tools is its value as original content.

This looks like an actual U87 circuit. The fake 103 has a hybrid circuit, TLM103 for the DC converter part and otherwise U87 circuit with a few errors/simplifications.

Thank you for your assessment! What errors, in particular, do you notice? What in your opinion could be improved here?

 

[Wordsushi]

I see a transformer inside, so it can never be a TLM! (TransformerLess Microphone .)
I also see a 180 pF capacitor that indicates a de-emphasis filter.

@Wordsushi: I have modified several 'Ali' U87ai's.
Rebiased the FET (all microphones seem to have a 7.5K source resistor!), increased the value of the 47 nF capacitor to 100 nF for a better LF response and tuned the 180 pF (original 160 pF) capacitor to obtain te desired high-end. After these minimal modifications, the 'Ali' U87ai sounds identical to the 'real thing'...
So far I always kept the original capsules.

@Ruud - You are a wizard! This is exactly the kind of info I need to hear. May I ask, is R105 the bias resistor, and is C104 the low end contour capacitor on the Ali87ai?

 

[RuudNL]

The components to 'fine tune':

 

[OneRoomStudio]

Most of the ones I'm seeing of that model run ~$200 USD. For a few hundred more than that, you could get one of the "U87ai" mics with functional switches, wooden case, and shock mount. Just a thought.

 

[OneRoomStudio]

Plus, they're so clever about getting around trademark issues

 

[Wordsushi]

Most of the ones I'm seeing of that model run ~$200 USD. For a few hundred more than that, you could get one of the "U87ai" mics with functional switches, wooden case, and shock mount. Just a thought.

That's a very good point. I do admit I'm very curious to try one, but I don't use multi-pattern, pad or roll off or need a box or a shock mount, and my current thinking is that I go down the rabbit hole with the fake 193 first. I'm willing to part with $220 (sales tax included) on a whim for this more than I am willing to spend $500-550 on a whim.
A second consideration is, again, content. "Is this an actual $200 U87ai?" is about as sensationalized as I can imagine for a clickbait-ish title, if I'm going to be a total prostitute about it. In this regard, strategically it would make more sense to do the fake 193 first, and if that content's performance merited further exploration of the potential of fake Ali mics, then following up with the fake 87ai is a no-brainer. Someone who buys, or just covets a fake 193 (if it sounds good enough) may be more inclined to also buy a fake 87ai if they saw that at a later date than doing the fake 87 first and the 193 afterwards.
Still, I'm on the fence. I'm heavily leaning toward getting one of these to satisfy my curiosity. And I'm sure as @SparkleBear and many here can attest, there's just a magnetic pull about wanting to know "what would this sound like if...?"

 

[Wordsushi]

The components to 'fine tune':
View attachment 124050

Ruud, dude, you are the best. Ok, just so I can be spoon fed here, I've attached a pic with those components marked. Is this correct?

 

[soliloqueen]

The bias resistor is marked RS I think.

 

[RuudNL]

This is the effect of increasing the value of the 47 nF capacitor. (C104)

Rs (R source) is indeed the bias resistor. Other components are correctly marked.

 

[Wordsushi]

This is the effect of increasing the value of the 47 nF capacitor. (C104)

Rs (R source) is indeed the bias resistor. Other components are correctly marked.

A-ha! That makes more sense. I initially thought the marking on the board was R5, but now that I've had my morning coffee I see the purple and green stripes on the RS resistor that align with your observation that they just initially stuff them with a 7.5k in that spot.

Thank you again, Ruud. You are always very generous with your knowledge and I really appreciate it. I have learned a lot from your posts over the last decade of reading this forum.

 

[svyet]

“Building a better mousetrap” implies that one already has available mousetraps, but instead better speaks to the innate human curiosity that makes us want to see “what would happen if…?”
And that’s where I am right now. I really don’t need another 87 style mic, but creating my little Frankenstein army of them, all with their slightly different flavors of 87-ishness, has become a bit of an obsession.
Also, a fairly major consideration to explore the dark underbelly of possibly turning the Ali fakes into competent professional tools is its value as original content.

In your line of work and for how long, I won't pretend to know what you need and don't need! Content-wise, of course it's brilliant. I'll be in line to watch out of the same curiosity. You're no doubt bringing DIY to a much wider audience in addition to those who are inclined to peruse these forums. And what I appreciate about the proliferation of great cheap equipment - much like with cameras over the years - it does give artists a much lower cost of entry and the ability to just focus on their art where equipment is no longer a sometimes-legitimate limitation. Sure, that will mean a lot more trash to sift through be it music or voice work (i.e. everyone is a photographer and/or podcaster now), BUT it does mean we get to discover some really great stuff that we otherwise might not if the artist had felt like the initial investment was too high (which we can definitely say it's not now). Though, I think we probably could have said that for a while now, as there have been successful albums recorded entirely on an SM57/58 through a cheap interface into a laptop. That brings me to the point that proliferation equally - however - does create the temptation to focus more on the gear now than ever before instead of just creating. The options are overwhelming and certain requires a lot more self-control - otherwise: analysis paralysis and loss of creativity. It's a two-edged sword, that's for sure. But someone just getting into it and watching things like your channel will give them a great head start, myself included! Rant over!

Plus, they're so clever about getting around trademark issues

View attachment 124053

Yes, that's exactly what I was talking about

That's a very good point. I do admit I'm very curious to try one, but I don't use multi-pattern, pad or roll off or need a box or a shock mount, and my current thinking is that I go down the rabbit hole with the fake 193 first. I'm willing to part with $220 (sales tax included) on a whim for this more than I am willing to spend $500-550 on a whim.
A second consideration is, again, content. "Is this an actual $200 U87ai?" is about as sensationalized as I can imagine for a clickbait-ish title, if I'm going to be a total prostitute about it. In this regard, strategically it would make more sense to do the fake 193 first, and if that content's performance merited further exploration of the potential of fake Ali mics, then following up with the fake 87ai is a no-brainer. Someone who buys, or just covets a fake 193 (if it sounds good enough) may be more inclined to also buy a fake 87ai if they saw that at a later date than doing the fake 87 first and the 193 afterwards.
Still, I'm on the fence. I'm heavily leaning toward getting one of these to satisfy my curiosity. And I'm sure as @SparkleBear and many here can attest, there's just a magnetic pull about wanting to know "what would this sound like if...?"

If money is no object, my vote goes for the 193 first before someone else gets to it. Way more interesting for me that something labeled as a 193 is actually a "legitimate" 87 underneath. And it lets you talk about two different mics. Would be important to note the size and proportions of the fake 193. Hard to tell from the pictures. The real one is pretty diminuative at only around ~170mm long and ~45mm at its widest (top of the headbasket). If the fake is the size of an 87, then it would be safe to say it's only labeled as a 193, but in fact it's an 87 clone inside and out - which is also interesting content, and a reason to keep your eyes peeled for stuff like this (i.e. "the best Ali 87 might actually be an Ali 193" haha).

 

[svyet]

rather "the best cardioid-only Ali 87..." but that kills some of the click-baitiness

 

[micolas]

Would be important to note the size and proportions of the fake 193. Hard to tell from the pictures. The real one is pretty diminuative at only around ~170mm long and ~45mm at its widest (top of the headbasket). If the fake is the size of an 87, then it would be safe to say it's only labeled as a 193, but in fact it's an 87 clone inside and out - which is also interesting content, and a reason to keep your eyes peeled for stuff like this (i.e. "the best Ali 87 might actually be an Ali 193" haha).

https://a.aliexpress.com/_Ew2jWkv

 

[svyet]

https://a.aliexpress.com/_Ew2jWkv

Thanks, @micolas, so it's slightly bigger than even an actual 87. There you go @Wordsushi, "the best Ali 87 might actually be an Ali 193"