KM84 DIY Body & PCB kit – CLOSED

[GraemeWoller]

There's an interesting physical difference between the MXL 603s and our kit.

Visually they're identical except for a fine mesh grill on the 603s capsule verses the punched plate on our one. BUT, the XLR housing of the 603s is longer internally and screws directly to the board, then the XLR pins are wired to the board not soldered directly to the PCB like ours. The MXL board is 3mm shorter and has no cutouts for the housing so our boards don't fit in the 603s body.

The capsule sounds different too, brasher and brighter, without the wonderful open, but mellow, character of our kit. That's what I noticed testing the 603s capsule with the same KM84 circuit as we're using anyway. I'm not sure if all 603s are like that but the one I was testing with this circuit was "interesting". Not bad, as such, just "interesting" and not to my tastes.

The original 603s circuit is transformerless too, but I didn't bother testing that, I just dumped it in favour of the Neumann circuit.

That's just the differences I noticed for sake of interest. All these mics are pretty much identical, just Chinese gear that helps us all make cool mics for much less cost.

 

[HosaMogami]

This was a super fun little build. Thank you guys so much for the work you put into this! Will definitely order more when the next run comes out!

 

[Banzai]

This was a super fun little build. Thank you guys so much for the work you put into this! Will definitely order more when the next run comes out!

Great to hear, and thanks for the confidence! 

 

[jordan s]

I'm having an issues with these guys on my first session with them. I set all the mics up on a drum kit, adjusted everything to my liking, tried out various mics on different parts of the kit and tuned everything up, they sounded great as overheads. Then I powered everything down, covered the mics with regular soft cases while still on the stands and left for the night.  When I came back the next day to record, both mics were fading in and out and distorting with loud drums. Unfortunately I had tracked a whole song before realizing. When I switched over to the little blondies I usually use, they worked perfectly fine.  Anyone have any ideas why they worked perfectly one day and not the next while nothing had changed? The symptoms sound like humidity or a dirty capsule but on brand new mics that had only been out overnight, partially covered, seems odd.

 

[gyraf]

humidity in the covers? that´s about the only obvious explanation, isn´t it, if both mics were affecterd?

Jakob E.

 

[jordan s]

humidity in the covers? that´s about the only obvious explanation, isn´t it, if both mics were affecterd?

Jakob E.

I suppose so. I find it odd because I've never experienced this before. I thought the covers would protect them from humidity. Maybe some time in a dehydrator would do the trick?

 

[Matador]

A day or two in a bag with desicant salts usually takes care of it.

 

[gyraf]

Unless having set up outdoor, I see no reason to ever cover up microphones (that are in use) overnight..?

Jakob E.

 

[Banzai]

I suppose so. I find it odd because I've never experienced this before. I thought the covers would protect them from humidity. Maybe some time in a dehydrator would do the trick?

Covers are great for dust, but can also trap humidity if not breathable enough. Especially in summer (or basements).

If you have a humidity gauge, you can check your room: 40-50% humidity is normal/ideal.

 

[AW_music]

Hello ,

I'm completing the assembly,
is it correct that i have to cut the moving pin on the plastic part screwed to the pcb?
This pin is way too long and i cannot  screw the capsule into the body.
Anyone has the same problem?

Nick

 

[TillM]

Yes everyone has this “problem”.
Just cut it. Be careful with trimming .

 

[jrmintz]

I'm having a problem with mine - the level is very, very low. I checked my voltages and there's one anomaly:

R9 + R10:  46.3V

R5 + R6: 23.1V

R4 + R5: 19.6V

C2 + R4: 10V

R1 + R7: 15.5V,  should be 46V

What would cause that, and is that what is also causing my level problem? I worked carefully and I believe everything is in the correct place and orientation. The only difference is that I replaced C1 with an axial polystyrene cap. I installed the original polypropylene cap incorrectly and I had to cut it out. I had the polystyrenes on hand. Thanks.

Thanks.

 

[gyraf]

Voltmeter impedance?

Jakob E.

 

[jrmintz]

Voltmeter impedance?

Jakob E.

Thanks Jakob. Any thoughts about the level problem?

 

[jrmintz]

Hi all,

It was me. The trafo wasn't hooked up correctly. Seems to be working fine now. Thanks!

 

[jrmintz]

Hi all,

Thought you might like to know that I tried the AMI T8 transformer in my mic and it makes the mic sound much more like my real KM84s. The Cinemag had a nice rich bottom but was noticeably darker than my KM84s - both of which are later ones with 5000 serial numbers. With the AMI it's much, much closer to the authentic tonal balance. The Cinemag is not at all bad, just not as authentic. Whether it's worth the additional cost is another question. I have no connection to the company, btw.

 

[Banzai]

Hi all,

Thought you might like to know that I tried the AMI T8 transformer in my mic and it makes the mic sound much more like my real KM84s. The Cinemag had a nice rich bottom but was noticeably darker than my KM84s - both of which are later ones with 5000 serial numbers. With the AMI it's much, much closer to the authentic tonal balance. The Cinemag is not at all bad, just not as authentic. Whether it's worth the additional cost is another question. I have no connection to the company, btw.

Thanks for trying it out!

Still waiting on the Haufe's to come through, to see if they're also a viable option in terms of price and availability.

 

[Hank Dussen]

Anybody has some extra 2N3819's?
They're not so hard to find but shipping costs are often €10 or more...

 

[Banzai]

Anybody has some extra 2N3819's?
They're not so hard to find but shipping costs are often €10 or more...

I can spare a couple!

Only have the two available though.

 

[Banzai]

Sale open!

To place your order, please follow instructions here:
https://groupdiy.com/index.php?topic=68360.msg869537#msg869537