There isn't really anything you can do to improve the 990 or 991 from stock. Their limiting feature is the uber-cheap capsule, not the electronics.

There are 2 things you can do to improve the 990 without changing the elctronics:

1) Remove the 2 outer layers of grille. You can carefully cut them away with a small pair of wire cutters. The outer layer is the cheap, thick aluminum grill and beneath that you'll find a very fine screen mesh. There are 3 layers of grill. The inside layer is soldered to it's frame so don't remove that or you'll lose your grounding. This gets the diaphram more "out in the open".

2) Coat the inside of the base with a heavy silicon and layer-in a thin sheet of rubber or dense foam-rubber if you can. That'll keep that cheap metal base from ringing so much and mucking up your upper-mids.

Those 2 mods are simple but you'll notice an immediate difference and male vox won't sound so "spitty". From about 2 feet or more away, the 990 is actually a really decent LDC for acoustic guitar that won't produce a lot of self-noise and picks up the qualities of your live-room pretty well. Doesn't make for a bad room-mic either and sounds pretty nice on celtic harp and female vocals. But I would recommend those 2 mods to nix out the inherent design flaws.

Thanks for the tips, I'll try taking off a few of those extra layers... also any tips for a tube pre-amp that may warm up the mids for this mic?

Believe it or not, the cheap MXL sounds really good through a rather cheap pre...the BlueTubeDP. As long as you use the balanced output. This pre is very decent sounding with a Tesla JJ tube instead of the stock Sylvania. An uppgrade to the op-amps does wonders as well....

I believe I got off point.

I like to split the output from that mic into a dual mono situation where I can color each side mildly. This, plus creative use of proximity effect on vocals makes this mic sound like a million bucks...I will have to see about one of the mods Coyote suggested, though. And carefully...

The Tesla/JJ tubes are great IMO. They have good clarity and a little less output than the usual stock 12AX7 so they're smoother.

I like the way the 990 sounds on some vocals too. Like a lot of other mics in all price ranges, sometimes it's just "the right mic".

I recently bought the Electro harmonix 12AY7 Tube Pre and I like it on the 990 alot. For $189 it's an amazing bargain IMO. It's got quality characteristics you typically only find in more expensive pre's like the Brick or a UA610. It's sound is extremely focused with enough dimension to represent the signal with outstanding accuracy. It's got just enough thickness and color to allow you to avoid the need for EQ and engaging the phase flip switch will give you a useful transparency if that's what you want.

You can also split the mic signal with it (which I like too) and you have complete control over the split output, which is balanced.

I like that pre alot with the 990 and The MK012 cardioid and omni capsule. Especially the omni capsule.

CoyoteTrax, I gotta say man, I removed that outter layer on the 990 last night and recorded some vocals through a Presonus TUBEpre and the difference was eye opening, who knew? Apparently YOU did! Thanks for the tips. As far as tip#2 goes when you say 'heavy silicon' is that the same kind of stuff I would pickup at a hardware store? Do you just fill the whole bottom cavity with the stuff?

Thanks!
Nick

I'm glad that worked out for you SS. It's not a bad capsule once you've exposed it a little.

Dampening the resonant ring in that cheap metal body is the next step and I'm not sure you can fill the bottom as you suggested but what I did was just take some silicon caulking, wiped it around the inside of the body rather heavily and applied a layer of rubber sheeting from the hardware store. Let it setup for about 24 hours and that's it.

The idea is to add dampening weight to the inside of that body so you can layer most any rubber sheeting or dense neoprene. Whatever you find at the hardware store you think is suitable. I haven't found a certain product that I'd recommend specifically.

hmmmmmm I might have to try this trick.

CoyoteTrax wrote: There are 2 things you can do to improve the 990 without changing the elctronics:

1) Remove the 2 outer layers of grille. You can carefully cut them away with a small pair of wire cutters. The outer layer is the cheap, thick aluminum grill and beneath that you'll find a very fine screen mesh. There are 3 layers of grill. The inside layer is soldered to it's frame so don't remove that or you'll lose your grounding. This gets the diaphram more "out in the open".

2) Coat the inside of the base with a heavy silicon and layer-in a thin sheet of rubber or dense foam-rubber if you can. That'll keep that cheap metal base from ringing so much and mucking up your upper-mids.

Those 2 mods are simple but you'll notice an immediate difference and male vox won't sound so "spitty". From about 2 feet or more away, the 990 is actually a really decent LDC for acoustic guitar that won't produce a lot of self-noise and picks up the qualities of your live-room pretty well. Doesn't make for a bad room-mic either and sounds pretty nice on celtic harp and female vocals. But I would recommend those 2 mods to nix out the inherent design flaws.

do you have any pics of the finished product?

I don't have any pics. I probably should have taken before and after shots but it was a "spur of the moment decision".

I'll take some after-the-fact pics this weekend and post them.

So i tried #1, but i haven't had time to test it out yet. I wanted to let people know that 1. you must be patient because its going to take a while. 2. Wear goggles so when you are cutting the wire little pieces aren't going to fly in your eyes. 3. I tried to clean it up as much as I could but now there are some little pieces of wire hanging off the edges of the grill. and 4. if you make a few cuts in the soft middle mesh to the point where you can grab it, you can pull it off the microphone pretty cleanly without leaving any excess material.

Ok thats all i have for now, i'm eager to test it.