JLI-103 Unscientific Impression

[stridentlinear]

On a quest to salvage something useful out of a few cheapie mics I've upgraded from, but still hoarding. I saw the JLI-103 capsules listed on JLI. I remember reading the 103 capsule as being inspired by the 67, but designed for a flat circuit, so just a little less bright than a k67 as is.

My completely unscientific observation: They're still on the bright side, but noticeably less so than the stock k67 types they replaced in two of my junk mics. A tad more modern as opposed to vintage-y, but still neumann-y. I totally think these are usable mics now, and I didn't have to radically change their character or order a million tiny capacitors from digikey.

Totally underrated benefit: Proximity effect (or lack of) is excellent, as are plosives (or lack of). Get right up on it and belt away. For whatever that might be worth. Disclaimer: I'm not in any way affiliated, and aware they also sell some duds (some of which I've been invoiced for). That is all.

 

[soliloqueen]

I took this apart a bit ago, here it is next to a real K103:

I think the thru holes are slightly smaller. Diaphragm may constitute some difference. I believe AYM uses 3 micron film. There are also tuning differences possible. All in all, it's a close clone. It's closer to its original than most other third party capsules available.

 

[rock soderstrom]

All in all, it's a close clone.

Looks very similar.

 

[stridentlinear]

Interestingly, the better u87 clones out there focus on tuning the capsule to correct the high end bump of the 67 capsule, rather than trying to duplicate the negative feedback circuit. And their methodology being fewer backplate holes (one poster here even used epoxy to close some of them). Which is pretty much what Neumann already did with the 103, only they go the extra step of sealing the backplate altogether (apparently not fans of epoxy)? (forgive my lack of technical nuance -- I'm just pretending to know what I'm talking about).

My ears at least tell me if you're going to make a u87 knock-off, you'd want to start with this capsule (tlm103 is still a lot closer to a u87 to me than an akg perception, just being honest).

 

[kingkorg]

My ears at least tell me if you're going to make a u87 knock-off, you'd want to start with this capsule (tlm103 is still a lot closer to a u87 to me than an akg perception, just being honest).

No, "closed" holes on tlm103 affect the damping of the diaphragm, and capacitance. It behaves much different than k67, not related just to frequency response. You are forgetting the rear backplate on 103, which doesn't have a diaphragm at all, it is just a metal plate with some holes in it, a lot like Røde nt1 capsule. This affects how polar pattern is created. K103 and k64 have very little in common.

To nail the u87 you have to nail the capsule, headbasket, and de-emphasis. If the capsule is of the right FR shape but slightly darker or brighter, you can just compensate by adjusting the circuit, the result would be the same. The trick is that you need good acoustic measurement system and a reference u87 you want to nail. Anything else is just a shot in the dark.

You simply can't do it by ear because of high Q notches here and there which are difficult to hear at first, but are very obvious under certain conditions.

Until recently that Perception capsule was the closest thing you could get to Neumann. Your ears are playing tricks on you because of the wrong headbasket on the Perception.

 

[k brown]

If JLI's published response is even within shouting distance of the actual, I'd sure prefer it over the Neumann - yikes!

 

[k brown]

No, "closed" holes on tlm103 affect the damping of the diaphragm, and capacitance. It behaves much different than k67, not related just to frequency response. You are forgetting the rear backplate on 103, which doesn't have a diaphragm at all, it is just a metal plate with some holes in it, a lot like Røde nt1 capsule. This affects how polar pattern is created. K103 and k64 have very little in common.

To nail the u87 you have to nail the capsule, headbasket, and de-emphasis. If the capsule is of the right FR shape but slightly darker or brighter, you can just compensate by adjusting the circuit, the result would be the same. The trick is that you need good acoustic measurement system and a reference u87 you want to nail. Anything else is just a shot in the dark.

You simply can't do it by ear because of high Q notches here and there which are difficult to hear at first, but are very obvious under certain conditions.

Until recently that Perception capsule was the closest thing you could get to Neumann. Your ears are playing tricks on you because of the wrong headbasket on the Perception.

Which Perception are you referring to - the dual-diaphragm one?

 

[kingkorg]

Which Perception are you referring to - the dual-diaphragm one?

Yes, it's the Takstar produced one, also available from JLI.

 

[k brown]

Thanks.

I didn't care much for the single-diaphragm Perception capsule; is it known who made that one?

 

[kingkorg]

Thanks.

I didn't care much for the single-diaphragm Perception capsule; is it known who made that one?

Also Takstar to the best of my knowledge. But it does perform differently.

 

[stridentlinear]

Until recently that Perception capsule was the closest thing you could get to Neumann. Your ears are playing tricks on you because of the wrong headbasket on the Perception.

From what I've gathered, the Perception (and others) were flawed for a number of reasons, and the de-emphasis circuit wasn't working as it should. And if it were easy to reproduce, then why would the likes of Advanced Audio, 3UAudio, etc. focusing on the capsule instead of the circuit?

I can't speak for "nailing a u87." Just saying that replacing the capsule with the the 103 variant gets you closer to at least a u87 inspired sound than whatever else is out there in the budget range.

 

[kingkorg]

I can't speak for "nailing a u87." Just saying that replacing the capsule with the the 103 variant gets you closer to at least a u87 inspired sound than whatever else is out there in the budget range.

Well i just explained why it isn't, but of course you have right to your own opinion.

And if it were easy to reproduce, then why would the likes of Advanced Audio, 3UAudio, etc. focusing on the capsule instead of the circuit?

Because they are in retail business, and they have financial benefit? You can't make much money by tuning one capacitor. Akg has more resources and knowledge than both. Advanced Audio doesn't make capsules.

Im not trying to counter you, just present what are by now well established facts. All of this has been discussed here before. Try to stay away from marketing plots presented by different "manufacturers".

 

[kingkorg]

One more thing, k103 is not made to be k67 for a flat circuit, someone somewhere just stated that and people went with it. It is it's own thing, made to be part of budget, low noise, allrounder mic.

Take a look at off axis polar pattern shape per frequency and you can see these have very little in common.

 

[stridentlinear]

Because they are in retail business, and they have financial benefit? You can't make much money by tuning one capacitor. Akg has more resources and knowledge than both.

I think the opposite is probably true. AKG pretty much markets that model to the guitar center masses who don't know much better. Whereas the more "boutique" or value-added suppliers are putting more thought in to things so as to tailor to the more discerning crowd willing to pay more than a hundred bucks (exaggeration but you get the idea).

Advanced Audio doesn't make capsules.

Most don't, but they do have them made to their specs, and there is some thought put in to the engineering. From AA's site regarding their k67 variant:

Our AK67 is an improved version of the venerable K67 capsule used in the U67 and U87 microphones. The AK67 has a 35mm OD with dual back-plates skinned with 6 micron German Mylar. The larger OD increases the low end response and more damping holes are drilled to tame the HF rise another 2-3db from the original K67.

And this seems to be common among the smaller operations across the board. Focusing on the capsule rather than the circuit for the HF de-emphasis. Like you mentioned, probably making more sense from a manufacturing standpoint. If "nailing the u87" is the goal, then obviously none of this really matters, but if you're okay with "somewhere in the ballpark," then none of the v67s or Perceptions of the world are going to get you there because no one is bothering with nailing the circuit at this point -- even most of the diy community has moved on from that.

 

[Gus]

A few things

The N channel, PNP with about a 2:1 output transformer microphones can be adjusted. Adding a larger value cap for the 220pf is not the best way.
People that post on forums are missing an important part of how the 87 67 etc circuits work.

If you do some reading you can adjust the circuits to the capsule OR you can EQ it after.
The grill shape, diameter, dome or flat bottom, mesh hole sizes and % open area, height of the capsule in the grill, damping if present and a few other things are important.
That is why I don't understand how people like the BM800 with cylinder grills I have two and not much you can do with that setup.
You can make some 32mm sound OK if you adjust the EQ and capsule environment.

It might be better to focus on the capsule environment than changing the capsule

What are you posting about "even most of the diy community has moved on from that."
People have figured stuff out and I am guessing that might be like me in not posting things that some "designer" will take and call there own

I learned early not to believe what you read on the web about microphones. I bought some based on what I read in the early 2000s and there not that impressive. I had an early VM1 that had a weird high end. I have read on this forum the capsule was changed in later models.

 

[stridentlinear]

What are you posting about "even most of the diy community has moved on from that."

Moved on from the idea that they can get a cheap mic to sound like a u87 with reasonable amount of effort/time/expense.

It might be better to focus on the capsule environment than changing the capsule

Definitely a huge part of it.

 

[stridentlinear]

One more thing, k103 is not made to be k67 for a flat circuit, someone somewhere just stated that and people went with it. It is it's own thing, made to be part of budget, low noise, allrounder mic.

I think the intent was to also offer a bit of the Neumann magic to the project studio or recording musician, and they succeeded there.

 

[Icantthinkofaname]

I think the opposite is probably true. AKG pretty much markets that model to the guitar center masses who don't know much better. Whereas the more "boutique" or value-added suppliers are putting more thought in to things so as to tailor to the more discerning crowd willing to pay more than a hundred bucks (exaggeration but you get the idea).



Most don't, but they do have them made to their specs, and there is some thought put in to the engineering. From AA's site regarding their k67 variant:

Our AK67 is an improved version of the venerable K67 capsule used in the U67 and U87 microphones. The AK67 has a 35mm OD with dual back-plates skinned with 6 micron German Mylar. The larger OD increases the low end response and more damping holes are drilled to tame the HF rise another 2-3db from the original K67.

And this seems to be common among the smaller operations across the board. Focusing on the capsule rather than the circuit for the HF de-emphasis. Like you mentioned, probably making more sense from a manufacturing standpoint. If "nailing the u87" is the goal, then obviously none of this really matters, but if you're okay with "somewhere in the ballpark," then none of the v67s or Perceptions of the world are going to get you there because no one is bothering with nailing the circuit at this point -- even most of the diy community has moved on from that.

Advanced Audio's K67 still has about a +7dB boost at 12K. I'm pretty sure Neumann's capsule is +4 or 5 dB there. So that's already incorrect. It's 2-3 dB darker there than something like the RK67 (or whatever AYM calls it originally) or similar super bright capsules. You can definitely tell the CM87 is bright because of this as it doesn't use the HF attenuation that's supposed to be in a U87, Dave will build it in if you pay for the CM87se, but even then you HAVE to request it. It's the reason I won't touch an Advanced Audio product.

I also wouldn't say the DIY community has moved on from thinking they can get a DIY or modded cheap mic to sound like a U87, there's just nothing left to talk about there unless you're doing something more original like building it with a switch that controls the high frequency roll off or you're putting a lot of effort into increasing the capsule polarization voltage and figuring out the best components to use to make it as quiet as possible. As long as you can read the schematics and have to components you should be able to build it pretty easily following the discussion that's existed for years.

The only thing that can really be done differently is using the correct body and headbasket shape and dimensions but Neumann has a design patent on the headbasket and sends C&Ds to companies that use a similar headbasket, look at the revised WA-87.

Because they are in retail business, and they have financial benefit? You can't make much money by tuning one capacitor. Akg has more resources and knowledge than both. Advanced Audio doesn't make capsules.

Im not trying to counter you, just present what are by now well established facts. All of this has been discussed here before. Try to stay away from marketing plots presented by different "manufacturers".

They sell capsules and transformers so of course they're gonna tell people how much they improved the capsules, even if it's wrong. I give 3U Audio a pass because of how good their stuff is for the price compared to similar offerings (for complete mics I mean). I won't touch Advanced Audio stuff because I can hear how bright it is and I have to pay them another $200~ USD for the CM87se and REQUEST that they use the circuit they're supposed to use to get it to sound like a U87. It's not hard to EQ their mic to sound right (I've done it with samples comparing it to a U87 and made them sound nearly indistinguishable) but I shouldn't HAVE to do that on a mic they claim improves on the original.

 

[stridentlinear]

Advanced Audio's K67 still has about a +7dB boost at 12K. I'm pretty sure Neumann's capsule is +4 or 5 dB there. So that's already incorrect.

So even they're not trying to nail the u87.

I also wouldn't say the DIY community has moved on from thinking they can get a DIY or modded cheap mic to sound like a U87, there's just nothing left to talk about there unless you're doing something more original like building it with a switch that controls the high frequency roll off or you're putting a lot of effort into increasing the capsule polarization voltage and figuring out the best components to use to make it as quiet as possible. As long as you can read the schematics and have to components you should be able to build it pretty easily following the discussion that's existed for years.

Not sure if building one from scratch qualifies as easy/cheap/inexpensive. But to some I suppose it is, which is great.. To me, even the very best of the modded v67s, Perceptions and the like can sound pretty cool, but still not like a Neumann. And as far as the $500-ish options go (Advanced Audio, Warm, 3u, etc.), they're all just shooting for "in the general ballpark." And if you're okay with that, then the 103 capsule I think is a pretty quick/easy alternative. You're in the ballpark of a Neumann LDC (if not a specific model) that gives you a nice improvement. And it probably only set you back $150 and a half hour's time as opposed to scouring the internets for schematics, ordering parts that may/may not be discontinued. -- Just my take on the matter, but certainly not the only valid take.

 

[kingkorg]

To get in u87 ballpark is relatively easy.

However if you want to nail all the aspects, the exact way it behaves under high spl, headbasket, fet/bias/transformer in respect of harmonic profile under different conditions, body resonances (or absence of these), transformer interraction with transformer coupled preamps, it could easily become never ending game.

All of these are relatively easy to measure in order to know what you are going for, if you have the original. Going by ear is a waste of time.

Under some "normal" conditions, vocal recording, voiceover, acoustic guitar, you will rarely get to the point where any of these really matter. Even though it's measureable, harmonic profile at reasonable level won't be audible no matter what anyone says.

I'd say nail the capsule, make the headbasket non resonant, non reflective, adjust bias/hf response, and as long as the mic doesn't ring like a church bell you are pretty much there. For anything more than that it would only make sense to buy the original, you will spare time and sell at good price once you get tired of it.