Question on the MXL990

[mrdarkside2k3]

For those of you that have the MXL990, I am looking to see where most people go with the EQ on it. I think I have a decent EQ on mine. I know it's all subjective to your ears, but I am just looking for comparisons.

 

[antichef]

the only eq advice I have is to replace the capacitor that's on the backside of the little circuit board (at the end closest to the capsule) inside the mic (the capsule coupler capacitor?) with a 1000pf value capacitor of some other type than what's in there (polystyrene is what I'm using). 40cent capacitor and $8 soldering iron, 5 minute job in my case. You can open it up by screwing the three little screws at the base of the mic *inward* (not outward, like I did) until the base will pull/drop out, pulling the innards with it.

This change mellowed and smoothed the sound of the mic quite a bit. Before, I really couldn't use it for much because it was harsh and edgy sounding, but now it's alright, and I usually don't think I need to eq it at all.

 

[mrdarkside2k3]

I will give it a shot. I will take it apart and look at the capacitor and see what I have to do to take it off. I have some soldering experience. Thanks

 

[P. Glaser]

Hey thanks, Antichef. I've got a 990 that I've never used because it sounds so harsh. I'll try this mod and see what happens. I've got 1000pf caps left over from when I did a mod on my 603s. BTW, would it make any difference in the sound to swap out any of the other caps? Thanks.

Mrdarkside. When I did the mod on the 603s, I found that the traces are very fragile. This time I'm going to just clip the old cap off and solder the new one to the old leads. Should be very easy.

Paul

 

[dgatwood]

Mrdarkside. When I did the mod on the 603s, I found that the traces are very fragile. This time I'm going to just clip the old cap off and solder the new one to the old leads. Should be very easy.

Well, that will work, but it would be more prone to coming unsoldered than doing it right, I would think.

My suggestion on that would be to start by removing all traces of solder using a solder wick. Once you do that, the fragility of the traces should be moot.

What usually causes problems for traces is someone pulling a lead halfway out with solder still stuck to both the lead and the trace while molten, then pushing on the part after the solder resolidifies, thus lifting the trace from the board. It's easy to do that---I've done it myself on more than one occasion. It's also easy to fix with cyanoacrylate glue if you don't tear the trace. If you do, that's what CircuitWriter(tm) pens are for.

Anyway, if you use a solder wick, the part should literally fall out by itself without the need to keep the leads heated, thus just about avoiding any real possibility of lifting the trace. If it doesn't fall out after wicking away the solder, at a minimum, the pins should wiggle when you touch the part, and a gentle tug should get the component out. If not, use a different spot on the wick to remove more solder.

Another useful thing to do is head up a needle (hold it with pliers) and push it through the hole from the trace side to clean out the hole, then carefully pull it back through. That way, when you push the lead through from the other side, you generally won't bump into any gunk in a via or whatever and end up with the lead catching the edge of the trace and lifting it.

 

[antichef]

I am going to write those instructions on my hand -- thanks!

In this particular case, the capacitor I'm talking about is soldered to two posts sticking out of the back of the top of the circuit board, and so there's no issue with traces, and it's pretty easy.

I think the 990 and the 603 are essentially the same mic - search around, and you'll see instructions for replacing more of the capacitors and other parts, too. I *think* that coupler capacitor is pretty much the only low hanging fruit, so to speak - that is, the other changes are more difficult and result in less improvement. For that reason, I haven't tried them.