Are MXL 990 and 991 really crap?

[hild]

I have a 990, what are some circuit-mod/parts-swap ideas? Can't wait to try out a new recipe on an old mic.

[@?,*???&?]

So hear is the deal. I'm new to mics, I'm not sure I want to start out with anything expensive. I was considering just s SM57 to start but I'm also in the market for monitors and will most likely be getting some KRKs and I can across a package with these 2 mics and some other junk to get me going. Are they worth bothering with? I'm mostly looking to use them for vocals.

For vocals? They will suck.

A great, inexpensive, starter mic for you would be the Shure KSM 27. It's got the necessary features of pad and hpf and also has a good 'sonic' character.

[Marik]

I have a 990, what are some circuit-mod/parts-swap ideas? Can't wait to try out a new recipe on an old mic.

First, have some search on the forums (esp. www.groupdiy.com) for MXL603. It is basically the same microphone, but the 990 has much larger body, so you have much more room for quality parts. The main capacitors to replace are input (C13) and two coupling (C3, C4) ones. Use your favorite quality types there and increase coupling capacitors value to 1uf. This will not increase the low end by two octaves, as somebody made a claim here, but you will still here an improvement.
Removing the mesh layers will improve the sound, as well.

Then comes the capsule...

The main complaints about those microphones (and capsule being the main contributor) is lack of bass, peaky high frequency response and crappy cardioid pattern.
In order to make this mic look more like a LD mic they use a brass ring around the capsule. It is actually one of the ways to increase the low end output, because of changing pressure gradient path. It however, creates another set of problems and screws up the cardioid pattern even further.

To address this problem I turn this capsule from two-chambered design into three-chambered one. That is, the original capsule has only one plastic piece behind the backplate giving us two chambers?1st between the diaphragm and backplate and the 2nd between backplate and plastic time delay piece. I add one more plastic piece for completely different time delay parameters, which also affects the voicing and also gives much more flexibility in the capsule?s fine tuning, as well as resulting in a much tighter cardioid pattern over original capsule.

With the three-chamber design I get the flexibility of tuning the capsule and voicing it hundreds different ways--from very rich ribbon-like sound with thick low end and rolled off top, through the honky type of sound, with accentuated mids, to ruler flat response, i.e. I can manipulate with any range of interest, and custom voice them for any application. It is not a problem to tune it like say, KM84, or Schoeps.

As a final touch, I machine off the front of the capsule to reduce front cavity resonances. I also replace the grill mesh with a more rigid one and with much more open area. I form it into a dome to avoid parallel surfaces (and standing waves, as a result), ensure rigidity, and move it further from the diaphragm to reduce diaphragm damage.

Best, M

[jgimbel]

Digging up an old thread here. I've got an MXL 990 (with the 991 set) that I never use. I actually do use the 991 under snare when one is needed, and it does pretty well there. But the 990 never comes out. Last night I was thinking about how it's a bright mic and that it's always sounded too crispy to me on things like acoustic guitar and vocals. Lately I've had some tracks where I was using a 57 on snare and the 991 under, and I wanted more top end, but from the top mic, not actually the sizzle of the snare. I've been looking at getting an Audix i5 as I've heard some great comparisons between the i5 and a 57 and it seems to have more up top. I thought I'd try the 990 on snare, since it's not a mic I care too much about and it's definitely got more up top than a 57. I did a really quick test today, and what do you know, it actually sounds pretty damn good! It actually has a LOT in common with the i5's sound samples I've heard - not entirely un-57like, but with a boosted high end.

Here's my quick test from today. It's just the 990 on snare, into an API 312 clone with the pad on. I decided not to put other mics up just to see if the condenser would pick up way too much of the rest of the kit. Some pretty bad drum playing, and I also decided to throw a quick guitar part over the drums to see how a guitar sound interacted with the snare (guitar also just with the 990 on it, a few feet back). Some compression on the guitar, nothing at all on the snare. Here's the clip:

http://jessegimbel.com/990snare.wav

I think it sounds pretty decent and could work beautifully in the right mix. The bleed isn't so overbearing either, and I was able to gate the snare track easily to cut out bleed, so it's definitely doable if needed. I was impressed! And hell, it's cheaper then a 57, if I blow one up it wouldn't be hard to find another.



*Sidenote, before posting here I did a search for Tape Op threads about the 990, very interesting to see how opinions change over the years. In 2004 a lot of people were asking about it, and it got RAVE reviews by a lot of posters, including people who have thousands of posts on here. Everything from saying it's a nice beautiful airy mic that should cost hundreds more, to saying it has absolutely no trouble being alongside Neumann U87s. The opinion of the mics has generally declined now, to the point that many people consider them unusable trash. Just interesting to see how the reputation of a mic, at least for the first few years, can have nearly as much to do with hype and who's using it as how the mic actually sounds.

[LupineSound]

I think they make great, inexpensive drum overheads.

[IanWalker]

I think they make great, inexpensive drum overheads.

That's where I've used my 990s the most, although not in a while.

I've used them on acoustic guitar and vocals with some decent results, too. Monkey around with placement, and a pop screen for vox, and you can get some perfectly serviceable results.

Example:
http://michigansoundservices.com/media/ ... istmas.mp3
Male vox and acoustic with the 990, into an MBox.
Forgive the somewhat-out-of-tune violin playing.

[studiodog]

They work pretty well for drum over heads...

[kickoldman]

+1 on ripping out the inner layers of mesh. That made an immediate and positive difference.

I also did zapnspark from micbuilders "direct coupling" mod, which was dead simple and eliminated a few components. I haven't been able to A/B with an unmodded mic since then, but it *seems* like it sounds better. I'm gonna try to get my hands on an unmodded mic this weekend and make a direct comparison.

I've never been too excited by these mics, but they've never utterly sucked either.

[digitaldrummer]

changing caps helps too, but they are what they are.... and they are not a $1000+ mic.

[IanWalker]

I also did zapnspark from micbuilders "direct coupling" mod, which was dead simple and eliminated a few components.

Care to share a link?

[kickoldman]

I also did zapnspark from micbuilders "direct coupling" mod, which was dead simple and eliminated a few components.

Care to share a link?

I wanted to double-check with zapnspark before posting his schematics. With his permission here ya go. The component numbering on the schematic corresponds with the MCA SP-1, but it's easy to figure out what's going on.

Again, this is all from the Yahoo micbuilders group; tons of cool information there. Larger pics can be viewed here: https://picasaweb.google.com/1179900452 ... ariousGear#

The general concept:


Stock schematic:



modded schematic:

[IanWalker]

So like a few people have mentioned doing, I ripped out the two inner layers of screens on one of my 990s.

I figured I would see how it compared to the unmodded mic, and while I was at it, I figured I'd share what I found.

They were placed on a stereo bar as close to coincident as I could get them, and angled in slightly so they were pointed at the same fret on my guitar, sitting about 12" out from the upper bout.

They went through my Rane preamp and direct into my Digi002 for a/d conversion. No post processing.

My playing is somewhat lackluster, but I feel like it gives enough of an example of what the mics sound like.

In this first photo, you can clearly see the difference in the screen between the two mics:


This second photo is the angle they were at when I was recording:


For sound examples, I'm going to give you 3 selections I played. Once with each mic. For fun, I'm not going to tell you straight off which mic is which sample, I'd like to hear some guesses.

mp3s:
http://michigansoundservices.com/990s/1a.mp3
http://michigansoundservices.com/990s/1b.mp3
http://michigansoundservices.com/990s/1a.mp3
http://michigansoundservices.com/990s/2a.mp3
http://michigansoundservices.com/990s/2b.mp3
http://michigansoundservices.com/990s/3a.mp3
http://michigansoundservices.com/990s/3b.mp3

If you want to hear uncompressed versions:
http://michigansoundservices.com/990s/aifs.zip

After you've listened, and made a guess as to which mic is which (or didn't and just want to know), I tell you here:
http://michigansoundservices.com/990s/WhatsWhat.txt

Thoughts?

[eeldip]

right out of the gate, 1a sounded crazy peaky to me. like OUCH. 1b sounded smoother. but then when i listened back and forth, the difference seemed less dramatic. i think i was just SHOCKED at first listen.

basically, for solo acoustic i would probably never use a mic like this. but i could see this track poking thru a dense rock mix pretty well. honestly they both would do that trick pretty well. especially with a nice HPF.

bright nice is a very difficult thing for a mic to do. i would hope the full mod takes the edge off of this material!

[IanWalker]

right out of the gate, 1a sounded crazy peaky to me. like OUCH. 1b sounded smoother. but then when i listened back and forth, the difference seemed less dramatic. i think i was just SHOCKED at first listen.

basically, for solo acoustic i would probably never use a mic like this. but i could see this track poking thru a dense rock mix pretty well. honestly they both would do that trick pretty well. especially with a nice HPF.

bright nice is a very difficult thing for a mic to do. i would hope the full mod takes the edge off of this material!

Well, as for the peaky-ness of it, my less-than-stellar playing doesn't help that

In a real-world scenario, I'd probably have some compression on it too.

And yeah, I see why you probably wouldn't use this mic on solo acoustic, and I'd probably agree. But I've done it before, and it was a familiar sound source that I had on hand, and was actually able to play.

Maybe I'll try this with a somewhat warmer pre and see what that does for the sound.

Either way, I'll probably end up modding the second mic too, just so that they're as similar as possible, in case I want to use them as a pair.

[eeldip]

or you could just back off the mic a bit. bright mics work well from distance i find, as long as the room sounds nice.

screen mods, as i understand it, tend to deal with really HF stuff, prevent smearing there. as only the HF material bounces around those cages. i really didnt hear that much of a difference on the high highs, but mostly it was because i was distracted by the whole 5k, 6k, thing going on there. (also, listening on my grado 80s which are decently bright to begin with). PEAKY PRESENCE. the pokey frequencies.

i dont think it will hurt the mic to pull off those screens if you keep pop screens around for vocalists.