Upgrading a Solid State LDC

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Lo-Fi Mike

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can anyone point me in the right direction on upgrading a Solid State LDC microphone.

where do i by the part? which ones are good? how do i swap'em out?

thanks a lot for the help.:D
 
Which one did you plan on modifying? We'll have to know that to get you headed in the right direction.
Craig
 
Mxl 992

craigmorris74 said:
Which one did you plan on modifying? We'll have to know that to get you headed in the right direction.
Craig
Click to expand...

it's an MXL 992, i really like it for it's clarity and crispiness.
as far as LDC's i have an MA200 and a KSM27, and just recently an MXL 992.
When i tested this thing out it blew me away how clear and crispy the highs are. I thought "Man..This would be perfect for female vocals or the bright side of an acoustic.
I normally use my two NT5's for acoustic, They sound really good and full, but not as crispy as the 992. (not saying i would use the mxl alone on acoustic, but i would combine it with another condenser)

So to sum it all up, i love the sound of the MXL 992, but on the down side: It's pretty thin. If there was a way i could upgrade it to keep the nice high range clarity, but add more bigness (if that's even a word), Then it would be one awesome mic.

thanks for the response.:D
 
The should be at least a couple of capacitors in the signal path. Generally, these are ceramics (especially the one that usually couple the capsule to the FET) or electrolytics. Changing these to film caps typically works well. Just go to Mouser and search for polystyrene film capacitors and find the values you need.

We'll probably need a few more details about the cicuit before making recommendations about how to increase your bass response. You could post pics of the guts of the mic, or if you're comfortable doing so, sketch out the schematic.
 
also, could you either get up really close to it for proximity effect or use some eq instead?
 
l_732a36fbfff4a3aa3fb34e32aae6821a.jpg


Do you need a picture of the capsule (looks kinda hard to get in there)
but if you need one i will try.

by the way, thanks a-lot Craig
 
by the way,
two of the the three big black things read: 25V220uf
and one of them reads: 50V47uf

the blue square reads:
539TO
P502 w/ a 3362 on top

and the 4 light brown m&m looking things read:
1-102
2-102
3-27
4-15

and the 4 plastic black pieces with 3 legs all read:
2N
5551
Y-448

Just let me know if you guys need anything else :)
 
I don't have any mics using this circuit, but a lot of other guys on here do, so they might be able to point you in the right direction. Is there another PCB, or is that it? I'll look through my schematics and see what I can find.

EDIT: I think I might have a similar schemitic, but the part #'s are different. Sorry to ask so much, but could you filp the board over so I could see the traces on the other side?

Craig
 
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Lo-Fi Mike said:
is this what you mean by another PCB?
QUOTE]

I was actually thinking about the other side of the mic, but there's definitely some othe parts on that round board. Unless you can get a pic of what's on that round board, I'm probably not going to be able to point out exactly what needs to be changed. From what I see right now though, C15 and what looks like C14 to the right of it would be parts that I would change. What are they labeled?
Click to expand...
 
Well it looks like the 3 big electrolytics could probably stay because they are most likely Power supply filtering and finding those Large values in poly would be impossible to find much less fit in the mic...You could replace those with a Low ESR Type of electro cap which might help a bit .....

You could replace all of the Ceramic caps with Poly caps of the same Value ,but without seeing a schematic a I couldn"t tell you which ones are in the Signal path and what aren"t.....
 
Here guys.

I know these aren't the best pictures, but I'm in a bit of a rush to get out of here. I can do more detailed ones later.

I remembered I had kept the circuit boards out of a 992 so I took pictures (top and bottom) of the main circuit boards and the one underneath the grill that has the high pass filter and the pad. I had to paint out the background on one so I could compress it enough to upload. (it was all speckled)

Maybe it will help.
 

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i wonder why yours has Mogami written on it ( Just like Advertised)
but mine don't.

AM i a victim of false advertisement. :)

anyway, like i said the mic does sound good for what it does, just need to thicken it up a touch.
 
Lo-Fi Mike said:
i wonder why yours has Mogami written on it ( Just like Advertised)
but mine don't.

AM i a victim of false advertisement. :)

anyway, like i said the mic does sound good for what it does, just need to thicken it up a touch.
Click to expand...

Like 2 inches of wire is really going to make that big a change in the sound.:rolleyes:
 
Based on what's on that PCB by the capsule, I'm not familiar enough with this cicuit to for sure make a recommendation. Maybe one of the big kids will come in and help you out. PhilGood, can you tell which cap couples the capsule with the FET? That would be my biggest recommendation for change.
 
craigmorris74 said:
Based on what's on that PCB by the capsule, I'm not familiar enough with this cicuit to for sure make a recommendation. Maybe one of the big kids will come in and help you out. PhilGood, can you tell which cap couples the capsule with the FET? That would be my biggest recommendation for change.
Click to expand...

From what I can see in the picture, I think, but am not certain, that the long, rectangular cap on the round filter board is the coupling cap. I can't tell what kind of cap that is. It could be ceramic or it could be film. You'd just about have to look up the part number to know for sure. That packaging is sometimes used for both.

Those boards remind me a lot of the Apex 435 except that I think they consolidated it onto only two boards. If so, I suspect you'll find that none of the electrolytic capacitors are in the signal path. They're all used to filter the power for the circuits. I suspect you'll also find that the four ceramic caps, C8, C9, C14, and C15 are performing a similar function, but I'm less sure about that.

All of those yellow caps that look like somebody dipped two wires in yellow glue and they just sort of formed round blobs... those are either multilayer ceramic or tantalum. If they're tantalum, rip 'em out. If they're MLC, you could get away with leaving them, but then you wouldn't have much modding left to do; they're probably all in the signal path somehow, so you might as well replace them with film. :D
 
There doesn't appear to be one. This one seems biased in a peculiar way. The capsule connects at one standoff where an FET and the 1KM ohm resistor meet. The 1KM ohm resister branches off to two resistors, R14 then goes to ground. The other capsule lead appears to go down to the main board where it crosses the lead of R12 before being coupled to ground at C16. A tantalium marked 104 (.1uF), so I presume that one is it. It seems that all tants and ceramics in the top portion interact in some way with the signal path. C4 on the upper deck appears to couple from the FET to ground. I'd just replace all ceramics and tants with 50v films of the same value and see what happens. Heck, their only a few cents each.
 
dgatwood said:
From what I can see in the picture, I think, but am not certain, that the long, rectangular cap on the round filter board is the coupling cap.
Click to expand...

Thats actually the 1kM ohm (read 1 gigaohm) biasing resistor.
 
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