Become a Site Supporter and Never see Ads again!

Author Topic: MXL 990, 991 and Oktava 319 Mods  (Read 62142 times)

0 Members and 1 Guest are viewing this topic.

Offline Chuck

  • Trade Count: (42)
  • Needs to get out more...
  • *****
  • Posts: 10812
  • Gender: Male
  • time between the notes...
    • My recordings on the LMA
Re: MXL 990, 991 and Oktava 319 Mods
« Reply #30 on: October 25, 2010, 05:37:44 PM »
They looked like this before the mod:
Reality is merely an illusion, albeit a very persistent one.

Microphones: AKG C 480 B comb-ULS/ CK 61/ CK 63, Sennheiser MKE 2 elements,  Audix M1290-o, Micro capsule active cables w/ Naiant PFA's, Naiant MSH-1O, Naiant AKG Active cables, Church CA-11 (cardioid), (1) Nady SCM-1000 (mod)
Pre-amps: Naiant littlebox, Naiant littlekit v2.0, BM2p+ Edirol UA-5, Church STC-9000
Recorders: Sound Devices MixPre-6, iRiver iHP-120 (Rockboxed & RTC mod)

Recordings on the LMA: http://www.archive.org/bookmarks/ChuckM
Recording website & blog: http://www.timebetweenthenotes.com

Offline jbell

  • TDS
  • Trade Count: (149)
  • Needs to get out more...
  • *****
  • Posts: 4582
  • Gender: Male
  • Spreadicated
Re: MXL 990, 991 and Oktava 319 Mods
« Reply #31 on: October 25, 2010, 07:13:27 PM »
These look similar to the Avantone CK1.  Are they the same mic?

They looked like this before the mod:
Mics: DPA ST4011ER & 4018ER | Neumann kk 184 (matched)> Nbob/PFA
Preamps: DPA MMA 6000 | Audioroot Femto
Recorders: Sound Devices Mixpre-10 II | Sony PCM A10

-20        -12         -6        TDS   (32/48)     
]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]][}   
]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]][} 
__________________________
|Record|  Runtime: 4:19.99  {|||] 75%

Offline Chuck

  • Trade Count: (42)
  • Needs to get out more...
  • *****
  • Posts: 10812
  • Gender: Male
  • time between the notes...
    • My recordings on the LMA
Re: MXL 990, 991 and Oktava 319 Mods
« Reply #32 on: October 25, 2010, 07:55:53 PM »
They all start out as the same microphone, using basically the same circuit and the same capsule. Avantone may have better parts or QC. I have not opened up an Avantone.
Reality is merely an illusion, albeit a very persistent one.

Microphones: AKG C 480 B comb-ULS/ CK 61/ CK 63, Sennheiser MKE 2 elements,  Audix M1290-o, Micro capsule active cables w/ Naiant PFA's, Naiant MSH-1O, Naiant AKG Active cables, Church CA-11 (cardioid), (1) Nady SCM-1000 (mod)
Pre-amps: Naiant littlebox, Naiant littlekit v2.0, BM2p+ Edirol UA-5, Church STC-9000
Recorders: Sound Devices MixPre-6, iRiver iHP-120 (Rockboxed & RTC mod)

Recordings on the LMA: http://www.archive.org/bookmarks/ChuckM
Recording website & blog: http://www.timebetweenthenotes.com

Offline raymonda

  • Trade Count: (10)
  • Taperssection All-Star
  • ****
  • Posts: 1631
Re: MXL 990, 991 and Oktava 319 Mods
« Reply #33 on: October 25, 2010, 11:04:10 PM »
I did get the capsules modified. I touched them up with some Nickel Metallic (Krylon) spray paint.

What method did you use to sand them down?

Offline Chuck

  • Trade Count: (42)
  • Needs to get out more...
  • *****
  • Posts: 10812
  • Gender: Male
  • time between the notes...
    • My recordings on the LMA
Re: MXL 990, 991 and Oktava 319 Mods
« Reply #34 on: October 26, 2010, 09:18:44 AM »
I hand sanded the front chamber off with 80 - 220 grit sand paper.
Then, I wound some gaffers tape around the sanding attachment on my dremel. I wound enough so that I could slip the capsule housing over it with the capsule being tightly secured. Then I checked and adjusted the run-out until it was pretty even all around.

I turned on the dremel and ran it against increasingly finer sand paper until I got the thickness and chamfer that I wanted. I finished by running it against some ScotchBrite. I measured everything and proceeded with the next one. It took 3 hours total.
Reality is merely an illusion, albeit a very persistent one.

Microphones: AKG C 480 B comb-ULS/ CK 61/ CK 63, Sennheiser MKE 2 elements,  Audix M1290-o, Micro capsule active cables w/ Naiant PFA's, Naiant MSH-1O, Naiant AKG Active cables, Church CA-11 (cardioid), (1) Nady SCM-1000 (mod)
Pre-amps: Naiant littlebox, Naiant littlekit v2.0, BM2p+ Edirol UA-5, Church STC-9000
Recorders: Sound Devices MixPre-6, iRiver iHP-120 (Rockboxed & RTC mod)

Recordings on the LMA: http://www.archive.org/bookmarks/ChuckM
Recording website & blog: http://www.timebetweenthenotes.com

Offline Chuck

  • Trade Count: (42)
  • Needs to get out more...
  • *****
  • Posts: 10812
  • Gender: Male
  • time between the notes...
    • My recordings on the LMA
Re: MXL 990, 991 and Oktava 319 Mods
« Reply #35 on: October 26, 2010, 09:24:08 AM »
Hey Ray, do you know if these caps with fit on the MXL603/CAD GXL1200 bodies? Do they use the same diaphragm?

http://cgi.ebay.com/New-Mic-Hypercardioid-Capsules-MXL-CAD-Apex-45-/290467075180?pt=LH_DefaultDomain_0&hash=item43a12fd46c#ht_2088wt_906

http://cgi.ebay.com/New-Condenser-Mic-Omni-Capsules-MXL-CAD-Apex-43-/290467075171?pt=LH_DefaultDomain_0&hash=item43a12fd463#ht_2088wt_906

http://cgi.ebay.com/Condenser-Mic-Cardioid-Capsules-MXL-CAD-Apex-44-/290467075164?pt=LH_DefaultDomain_0&hash=item43a12fd45c#ht_2088wt_906

They are different than the typical capsule that came with these mics, as the vents are actually on the capsules. They're cheap too!



edit to add:
So far, his is one of the more satisfying recording gear mods I've done. It's so cool to be able to take the capsules apart and see exactly what the components are. If those eBay capsules will work, I'll have a pretty good pair of microphones with omni, cardioid and hyper-cardioid capsules for well under $200!

I've read everything I can get my hands on about these mics and have come to the conclusion that that are worth the work to mod.
« Last Edit: October 26, 2010, 09:36:08 AM by Chuck »
Reality is merely an illusion, albeit a very persistent one.

Microphones: AKG C 480 B comb-ULS/ CK 61/ CK 63, Sennheiser MKE 2 elements,  Audix M1290-o, Micro capsule active cables w/ Naiant PFA's, Naiant MSH-1O, Naiant AKG Active cables, Church CA-11 (cardioid), (1) Nady SCM-1000 (mod)
Pre-amps: Naiant littlebox, Naiant littlekit v2.0, BM2p+ Edirol UA-5, Church STC-9000
Recorders: Sound Devices MixPre-6, iRiver iHP-120 (Rockboxed & RTC mod)

Recordings on the LMA: http://www.archive.org/bookmarks/ChuckM
Recording website & blog: http://www.timebetweenthenotes.com

Offline raymonda

  • Trade Count: (10)
  • Taperssection All-Star
  • ****
  • Posts: 1631
Re: MXL 990, 991 and Oktava 319 Mods
« Reply #36 on: October 26, 2010, 08:59:29 PM »
These don't look to be the right match for the MXL's and are not the same ones I bought off e-bay a while back. Wait until the others come back up on ebay.

Offline Chuck

  • Trade Count: (42)
  • Needs to get out more...
  • *****
  • Posts: 10812
  • Gender: Male
  • time between the notes...
    • My recordings on the LMA
Re: MXL 990, 991 and Oktava 319 Mods
« Reply #37 on: October 30, 2010, 06:39:34 PM »
I finished moding my CAD GXL1200 microphones today.
I took some pictures.
The first picture is the stock internals. The rest of the pictures are of the finished mics.

The next thing is to take them out and use them.



Reality is merely an illusion, albeit a very persistent one.

Microphones: AKG C 480 B comb-ULS/ CK 61/ CK 63, Sennheiser MKE 2 elements,  Audix M1290-o, Micro capsule active cables w/ Naiant PFA's, Naiant MSH-1O, Naiant AKG Active cables, Church CA-11 (cardioid), (1) Nady SCM-1000 (mod)
Pre-amps: Naiant littlebox, Naiant littlekit v2.0, BM2p+ Edirol UA-5, Church STC-9000
Recorders: Sound Devices MixPre-6, iRiver iHP-120 (Rockboxed & RTC mod)

Recordings on the LMA: http://www.archive.org/bookmarks/ChuckM
Recording website & blog: http://www.timebetweenthenotes.com

Offline jbell

  • TDS
  • Trade Count: (149)
  • Needs to get out more...
  • *****
  • Posts: 4582
  • Gender: Male
  • Spreadicated
Re: MXL 990, 991 and Oktava 319 Mods
« Reply #38 on: October 30, 2010, 06:41:31 PM »
Nice!  They look good
Mics: DPA ST4011ER & 4018ER | Neumann kk 184 (matched)> Nbob/PFA
Preamps: DPA MMA 6000 | Audioroot Femto
Recorders: Sound Devices Mixpre-10 II | Sony PCM A10

-20        -12         -6        TDS   (32/48)     
]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]][}   
]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]][} 
__________________________
|Record|  Runtime: 4:19.99  {|||] 75%

Offline illconditioned

  • Trade Count: (9)
  • Needs to get out more...
  • *****
  • Posts: 2998
Re: MXL 990, 991 and Oktava 319 Mods
« Reply #39 on: October 30, 2010, 07:35:35 PM »
^^ nice work.


Any benefit to replacing the 1G resistors?  I don't know if they introduce noise or not, but I'm curious.


Also, can you tell me something about the capsule?  Electret or externally polarized?  Does it have the Neumann-look front, a brass plate with regular pattern of holes in front of the capsule?


  Richard

Please DO NOT mail me with tech questions.  I will try to answer in the forums when I get a chance.  Thanks.

Sample recordings at: http://www.soundmann.com.

Offline Chuck

  • Trade Count: (42)
  • Needs to get out more...
  • *****
  • Posts: 10812
  • Gender: Male
  • time between the notes...
    • My recordings on the LMA
Re: MXL 990, 991 and Oktava 319 Mods
« Reply #40 on: October 30, 2010, 10:12:31 PM »
Richard, I have taken apart the capsule. It's a gold sputtered diaphragm, a couple of spacers then the back-plate, venting holes and the center connector. The front does not have a plate with holes in front like the Neumanns. There was an elaborate grill on the front of the mic, but it's recommended to remove that, so I did. I put a 3/4" stainless steel screen in front to replace it.

Here's a little bit about it:

http://recordinghacks.com/microphones/MXL/603S

There are photos on line showing the disassembled capsules, but I'm having trouble find them online now. It's my understanding that it's a true condenser.

The capsule gets a lot of praise, that's why I started messing around with this mic. I haven't recorded anything loud with it yet.

I do not have a source for 1G or bigger resistors, so I didn't change them or the stock transistors.


Edit to add photo of dissected capsule.
« Last Edit: October 30, 2010, 10:24:07 PM by Chuck »
Reality is merely an illusion, albeit a very persistent one.

Microphones: AKG C 480 B comb-ULS/ CK 61/ CK 63, Sennheiser MKE 2 elements,  Audix M1290-o, Micro capsule active cables w/ Naiant PFA's, Naiant MSH-1O, Naiant AKG Active cables, Church CA-11 (cardioid), (1) Nady SCM-1000 (mod)
Pre-amps: Naiant littlebox, Naiant littlekit v2.0, BM2p+ Edirol UA-5, Church STC-9000
Recorders: Sound Devices MixPre-6, iRiver iHP-120 (Rockboxed & RTC mod)

Recordings on the LMA: http://www.archive.org/bookmarks/ChuckM
Recording website & blog: http://www.timebetweenthenotes.com

Offline raymonda

  • Trade Count: (10)
  • Taperssection All-Star
  • ****
  • Posts: 1631
Re: MXL 990, 991 and Oktava 319 Mods
« Reply #41 on: October 30, 2010, 11:12:00 PM »
Nice work!!!!!!!!!!

Offline illconditioned

  • Trade Count: (9)
  • Needs to get out more...
  • *****
  • Posts: 2998
Re: MXL 990, 991 and Oktava 319 Mods
« Reply #42 on: October 30, 2010, 11:23:36 PM »
^^^ Nice!  Thanks for the tech details.


  Richard
Please DO NOT mail me with tech questions.  I will try to answer in the forums when I get a chance.  Thanks.

Sample recordings at: http://www.soundmann.com.

kirk97132

  • Guest
  • Trade Count: (0)
Re: MXL 990, 991 and Oktava 319 Mods
« Reply #43 on: October 31, 2010, 03:53:53 PM »
Chuck...first off, nice work!  So I see you had replaced a lot of stuff.  And I am wondering about a lot of things.  Should I ask here or would you rather take it to PM's or e-mail?  Thanks, Kirk

Offline Chuck

  • Trade Count: (42)
  • Needs to get out more...
  • *****
  • Posts: 10812
  • Gender: Male
  • time between the notes...
    • My recordings on the LMA
Re: MXL 990, 991 and Oktava 319 Mods
« Reply #44 on: October 31, 2010, 04:20:38 PM »
Chuck...first off, nice work!  So I see you had replaced a lot of stuff.  And I am wondering about a lot of things.  Should I ask here or would you rather take it to PM's or e-mail?  Thanks, Kirk

Either way. But, keep in mind, I just followed instructions others have posted in various DIY forums. I didn't re-design anything. I can follow a schematic to stuff a circuit board, but I really can't design/re-design a circuit.

I started testing the moded mics this morning, while watching the Broncos lose to SF. :(

One of the bodies has 4-6dB less gain than the other and has a slightly different self noise sound. There is a 4v difference in the voltage getting to the capsules from the bodies. I have to admit that I don't have much experience working on transistor circuits. Op-amps I know pretty well, but transistors and biasing is not something I have done before. If biasing is even the problem ???

I replaced most of the resistors (hand matched values between mics) and capacitors, but left the main transistor 2SK170BL biasing resistors alone. I also didn't change any of the transistors.

Reality is merely an illusion, albeit a very persistent one.

Microphones: AKG C 480 B comb-ULS/ CK 61/ CK 63, Sennheiser MKE 2 elements,  Audix M1290-o, Micro capsule active cables w/ Naiant PFA's, Naiant MSH-1O, Naiant AKG Active cables, Church CA-11 (cardioid), (1) Nady SCM-1000 (mod)
Pre-amps: Naiant littlebox, Naiant littlekit v2.0, BM2p+ Edirol UA-5, Church STC-9000
Recorders: Sound Devices MixPre-6, iRiver iHP-120 (Rockboxed & RTC mod)

Recordings on the LMA: http://www.archive.org/bookmarks/ChuckM
Recording website & blog: http://www.timebetweenthenotes.com

 

RSS | Mobile
Page created in 0.059 seconds with 38 queries.
© 2002-2024 Taperssection.com
Powered by SMF