Oktava 219/319 mod Questions?

[tonycamp]

Its a transistor that looks like a little black semi circle with three legs off the bottom. Reminds me of the aliens in the war of the worlds movie. I think you were mistaking the transformer for this? Thats the big rectangular box at the base of the mic with multiple wires and the russian pencil writing on it.

 

[rokus666]

My bad, sometimes I mix up the words tranny and transistor... I'm a noob...I only do electrical stuff only when I build or modify things...I am mostly clear about concepts on how things work...I think...except the math part...

Well I have decided to buy already sourced kits from Sitler. I don't really have time to surf the web and source myself. I will replace all the caps, and leave the stock JFET...will try to document the process to help out the beginners and also to post some examples if I can...

 

[Gus]

FWIW

I have adjusted changed parts in a number of microphones sometime the stock parts work the best.
IIRC someone that posted here in the past changed their 319 parts and ended up liking the stock parts the best.  They saved the stock parts and then installed them again

If you don't know ohms law or understand biasing a Jfet etc changing the JFET in a circuit like the Oktava 219,319 might cause an issue.  As I posted before read the numbers on the transformer.

You might even like the ringing of the body.  A simple thing I did to damp the 219s bodies I have, is to use a small C clamp and gently tighten the haves together be careful you can break the microphone and also use padding between the clamp and body.  This is reversible and like I posted maybe you will like the body stock undamped.

I have not worked on a 319 but maybe you could use a  few screw/band hose clamps http://en.wikipedia.org/wiki/Hose_clamp with a rubber sheet between the body and clamp as a test for the change with damping.

I have compared adjusted 012s against stock 012s and stock sounds better with certain sources.

IMO the web has some good information and some ? information

 

[tchgtr]

  What I remember is someone saying that the Oktava 219/319/MC-012 are well biased at the factory (unlike a lot of the Chinese stuff), and all transistors are getting proper voltages. Best just to leave them alone.
  On the 319, I changed input and output caps (to polypro and polyester), removed some mesh from the screen, dampened the body, and removed all the switch wiring. Sounds great.
  Then I bought a second one, and left it alone, as the stock mic has a unique sound, very different from the modded one.
  I loved my pair of MC-012s stock, but changed the capsule to gate cap, and now I like them even more.

 

[rokus666]

I am sure the stock parts work well and give the overall character to the microphone design.  :-\

As I am looking inside both 219/319, some caps have rust on them/leaky. They have to go!
Of course, I will leave the stock JFET and try not to mess with electronics parts too much.

As the matter of fact, I am so curious to compare modded and unmodded. Will do so as I modify one by one and test them side by side.

And, by the way, all the four microphones have different resisrors and caps!

 

[rokus666]

Anyone knows where to solder the capsule leads on the PCB on 319 ?

 

[rokus666]

I have figured it out...silicon curing...

 

[rokus666]

Question:

how do you glue back the grill mesh onto the capsule cover???

Silicone? Or....

 

[HellfireStudios]

Question:

how do you glue back the grill mesh onto the capsule cover???

Silicone? Or....

Conductive epoxy would do the trick, but if you are sure the screen is grounded to the body, you can use JB Weld...

-James-

 

[rokus666]

What's a JB weld ? 

 

[Gus]

What's a JB weld ? 

Did you try google or bing or another search engine for your questions?

 

[rokus666]

What's a JB weld ? 

Did you try google or bing or another search engine for your questions?

Actually I have. I have successfully completed 219 mod following Dorsey's article.
I have recorded dozen of different instruments in studio side by side with stock 219. Stock sounds a bit harsh and mid-rangey, the only difference I have noticed, considering I was listening to a bunch of different instruments. Mod sounds a bit more open, not harsh and it seems that bottom end is punchier but it's extremely subtle. Definitely, this modded microphone has a warm vibe to it. Doesn't sound good on everything but it could be useful on some sources. I liked it on acoustic guitar a lot, not much on classical.
On accordion sounds nice. I wasn't impressed how it sounded on flutes. Banjo sound was all right, nothing special. Darbuka was also dull, actually the stock 219 won on this darbuka.

overall I think modded 219 could be very useful color mic to your cabinet.

Anyone care to hear the examples ???

 

[rokus666]

I am just wondering if electronic modification is necessary considering that major improvement in sound comes from removing extra stuff from the head basket.

 

[hazmatstrat]

Question:

how do you glue back the grill mesh onto the capsule cover???

Silicone? Or....

MG Chemicals 8331 Conductive Epoxy Adhesive...... Expensive will do about 4 to 5 mics..... no hummmmmm

 

[rokus666]

I have used some 2 part epoxy from home depot.

Actually, I have checked the conductivity of the mic body and the grill prior to using this glue. All went well...

 

[rokus666]

Ok, I am keeping all the recorded examples to myself. 

All Oktava modders businessmen will be out of business if I posted the AB mechanical VS electrical mod.
Electronic modification to Oktava microphone does nothing noticeable to the freq. response! If you don't believe, experiment for yourself. Considering I recorded 12 different instruments and listened in good acoustic environment(o300, ASP8, NS10). It does nothing to those 12.

Only mechanical mod to the capsule smooths out upper mid range.

Stock 219 is a great rock kick drum microphone. I am keeping one for only that purpose.

This is the reason why I got four Oktava 219 and 319 microphones so I can really see for myself what the mods do and how they sound like.

There is nothing magical as I was hoping to find.

Absolutely nothing. 

Moving on to 319's

 

[sebastianzetin]

is there an actual BOM for dorsey's mod? i have been searching for a long time. I found schematics but not a simple BOM. Thanks.

The upgrade plan is next:

-First I need to remove the pcb from the body which is kind of hard
-Dampen the mic body by killing resonance with silicon
-remove/chop off the grill bars on the front and back
-install some kind of shock mount between the capsule and the holder????? ???
-remove the capsule plastic screens (both of them?)
-replace the electrical components- Looking at Dorsey BOM but if anyone have other suggestions I will gladly take them

 

[ShaneSBG]

is there an actual BOM for dorsey's mod? i have been searching for a long time. I found schematics but not a simple BOM. Thanks.

I pretty much did these mods to my MK219's

http://www.recordingmag.com/resources/resourceDetail/316.html

I didn't use shortened teflon/silver wire & didn't removing the pad & HPF switching.  This switching is done with sealed reed relays opereated by permanent magnets, which are pretty clean in operation & I never experienced an issues with them, so personally I didn't see the point in removing this function.

I did find adding the caulking to damp the body resonances was quite a positive improvement.

The link to the  info is on the 1st page of this topic, but I added the quote here. At the bottom of that link there is a parts list and it also says all the parts except the Toshiba Fet can be purchased from Digi-key...even has the part #'s.
I have never done this and this thread is pretty old so I personally don't know if all that is still available, but I would assume so because that link itself is still good

I think that was what you were asking, no?