Topic: MXL 990, 991 and Oktava 319 Mods

[Javier Cinakowski]

I need to dig up some old posts/emails, but the k10 does not share the same capsule lineage as the 797 mics. Karma has something to do with the seelectronics/felio split.

The list earlier in this thread has mics that are made in-house, not rebranded.  797 and Felio arn't the only manufactures in hk/shanghai.    seelectronics has its own factory now, I would imagine they are similar to Rode, making their own mics from evolved 797 designs.  Just cause the threads are the same doesn't mean the actual capsule was made in the same plant.

[chris319]

earlier you said that your measurements were in reference to the manufacturer's curve, which I took to mean MXL's curves

I looked over my posts in this thread and didn't find myself saying that. I said my curves are 1/12 octave compared to other curves which are generally 1/3 octave.

Still, you have a cardioid, albeit a very wide cardioid, with -3dB at 20Hz.  That is unusual.  It's actually more typical of a small diaphragm omni.

Maybe so, but it's still a pressure gradient transducer owing to the existence of vent holes behind the diaphragm. If the bass response were deficient in this mic I'm sure it would show up just as it did with the E-V mics.

Joly's observed +8dB 8kHz peak is gone missing.

With all due respect to Michael, maybe that peak is in his ears rather than derived through actual measurement. The whole point of my setting up a measurement station is to bring some objective data to the discussion which has not been embellished by a manufacturer. The other option is to send these mics out for testing but that costs $$$.

BTW I did some proximity effect tests. It starts to become noticeable around 18" from the sound source, up about 1 dB at 50 Hz. At 24" it is so tiny as to be considered negligible.

[goodcooker]

Awesome...now I'll have something to do when it starts snowing 

[chris319]

I should elucidate on my proximity effect measurements. Going from 24" to 18", a small increase in proximity effect is observed on the order of 1 dB. Going from 24" to 30", the increase in bass due to proximity effect is tiny -- a small fraction of a dB. The measurements were made with a Shure SM57. The E-V N/D 367s, a cardioid, demonstrates that proximity effect is not a major factor in my measurements with a mic having such poor bass response.

I prefer to go by objective measurements rather than subjective guesstimates of what people think they hear, particularly when we don't know the characteristics of the device they are using to listen.

[chris319]

Yes clearly Mr. Fouxman and I are dilettantes who are incapable of making an objective measurement.

Good day to you.

What did I say to warrant such sarcasm? I never intimated that you are dilettantes. You are either set up to make measurements, in which case you have hard data as the basis for discussion, or not.

Good day to you, too.

[kirk97132]

Hey,  fwiw...Jon I really don't think there was any kind of put down or derogatory intent.   At least that is how I see it. 

This thread has been a wealth of knowledge and sharing and I for one would hate to see it go south like so many other mic mod threads have done...mostly over at GS.   

I have tons of respect to the guys who are building and/or modding mics.  Me, I'm just a wanna be electrical genius.  Lots and lots of want and very very very little traces of anything remotely resembling genius.   Of all the people who do this Jon is always the guy who is up front and willing to share.  Joly can get to be more salesman and when others enter into it  with Michael devolves quickly into off topic things. 

So before this turns into something else, I really have appreciated everyone's feedback and answers to me stupid questions.  I hope that I get to keep asking the questions here and this gets back on track to working on mics. 

The one thing I was going to post before this little hiccup......Chris do you have a stock 603 that you could test the same way as you tested the mod?  At least then we could compare the differences between before and after.  And maybe that would help to negate the method.  I cannot even begin to discuss some of this stuff on the level you guys do.  But I could see the difference between a before graph and an after graph. 

[Chuck]

Jim over on the gearslutz thread says those eBay capsules "will fit any 22mm pencil consenser mic 991,603 etc."

[chris319]

I do have a stock 991 somewhere. I'm not saying the bass response is due to a capacitor substitution. All we know is there is very little rolloff down to 125 Hz according to MXL.

[bugg100]

yeah, thats what i see there. i may order a pair of the hypers to try out. i really only tape din'ish on stage withe the drum kit in the nullpoint of both cards and am curious about hypers/super in this usage. this seems certainly the cheapest option for that.

I'm just concerned about the vents on the capsule as well as on the body, any input?

Joe

[Chuck]

I have the same thought.

[bugg100]

unfortunately there is no discount on combined shipping, still not unreasonable.

btw, same seller has the metal shockmounts in silver and black that come with the apex 185 stereo kit for about $15 each after shipping.

they work well for me despite being REALLY abused.  like when a rather large girl jumped on the back of a rather drunk, rather slight boy.... he held up for at least 10 seconds before going cheekbone first into the corner of the stage.... pulling my stand by the cables onto the floor in a vain attempt to save himself.... the band (gentleman jesse and his men) were so freaked out by dude being knocked cold that they stopped mid-song to check on the poor guy.  i got a great tape with an interesting interlude and he got cool scar.

These shocks work....

[Chuck]

The first outing with my modified CAD GXL1200's was a huge disappointment.
They both sound very, very thin. No bass at all. I haven't run a spectrum analysis yet, but I'm guessing that everything below 120Hz is gone. I ran them within inches of my C-463s into the DR-680 and the difference is huge. AKG's sound warm and round. GXL1200's extremely thin and tinny.

There must be a problem with one or more of the values of the components I swapped out.

I ran them twice yesterday. First at an acoustic in-store The Gracious Few performance and then later that night at the Black Sheep. I ran them into a Busman UA-5 at the in-store and got the same extremely thin sound. My C-481's sounded great on the same mic stand at the same event.

I'm not really sure how to proceed on figuring out what is wrong. If one of them had an issue, it would be easy enough to just examine all of the components and figure out what the difference is. But, they both sound the same, really bad.



Edit to add:

Short samples:

TGF_GXL1200.wav
http://www.filesavr.com/B4gml4FH

TGF_C-463.wav
http://www.filesavr.com/UsIL0XV0

These links don't work correctly using Google Chrome. They work OK with MS IE. Go figure 

[kirk97132]

Bummer dude. 

[Chuck]

lol

[chris319]

Chuck -

Did you make before and after recordings with these mics?