octavia mk 319 dumb question 1 and smart question 2

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pucho812

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Oct 4, 2004
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Tried to get the grill off and failed. I took out the four screws and it wouldn't budge. I wasn't too sure about forcing it off as I would hate to damage it. I tried a lil force and nada.
Is it glued on? am I missing something?

question 2
what would happen if I put a 1 gigohm resister in the place of r1 in this mk319 circuit?

MK1319.jpg
 
on my 219 (maybe similar construction??) the thinnest end of the case (where the socket is) is kinda sprung together using copper shims.

i managed to get a screwdriver blade inbetween my case halves and twist to persuade the halves to come apart.
 
yes the case has very tightly wedged copper shims for unknown reasons. use a small screwdriver and it will pop right apart.

if you replace R1, you must replace R2. this IS an upgrade. some even try for 2G resistors.

replace c2 with a 1000pf poly(ester, pro or styrene for different tastes) right away. there are other well documented mods such as changing the JFET and other caps. Do a search and you will find a lot. look for mods for a mk219, which has the same stuff inside..

:guinness:
 
Two 2 gigs for the 680 megs in that circuit will be close to the highest value and still at the low noise part of the input R vs noise of a FET, AN06 at Vishay.

The 680 megs are ok with that circuit and capsule IMO.
 
" Now the 219 I have are not worth the time I worked on them. The capsule is not that good, I like the 32mm china ones better. "

agreed, however, Some capsules seem to fair a little better than others whn it comes to the russian mics. mine is decent, but others I have messed with are bordering on terrible. YMMV.

the studio projects cheapos may be cheap but are leaps and bounds better for starters.
 
yes the case has very tightly wedged copper shims for unknown reasons. use a small screwdriver and it will pop right apart.

if you replace R1, you must replace R2. this IS an upgrade. some even try for 2G resistors.

replace c2 with a 1000pf poly(ester, pro or styrene for different tastes) right away. there are other well documented mods such as changing the JFET and other caps. Do a search and you will find a lot. look for mods for a mk219, which has the same stuff inside..
:thumb:
thanks man.. :guinness: :guinness: :guinness:
 
I no this is old thread but was wondering has anyone  tried a tube circuit in a 319 /219 ? or has anyone used capsule or transformer for other DIY mic ? or has anyone tried a different capsule & or transformer in a MK 319 ?....Im currently messing with a 319 stock & I think its is great for the money...Imliking it on vocals......Cheers
 
I've got some chinese capsules in my upgraded 219s.  Picked 'em up on the bay a few months back.  They were pulls from ADK Hamburg mics and were being sold by ADK.  Also sprayed down the inside of the body with a few layers of rubberized undercoating, pulled off the inner grille mesh, and cut away the metal bars in front of the grille.
The chinese capsules are quite a bit brighter than the stock capsules, which is a good thing in this circuit (IMO).  The stock mic was pretty dark sounding.
 
Years ago there was a site up for some guy who I think lived in the wilds in California, who managed to squash a valve into a MK219.  I can't for the life of me remember his name or the site, but I do seem to remember he was crazy about his cat, & every picture seemed to have his cat somewhere in it.

But anyway it is possible although I think he said t was a bit tight !!
 
Thanks guys yeah I seem to remember a chap like that there was a pic of cat walking thru tube pre he was building.....I have a similar cat he singes his fur on my sodering iron treads on my keyboad & sits i front of the bloody monitor...
Anyway Im just wondering what anyones done with the octavas I know theres m jolly mod site seems lots people rate them & lots hate them I borrowed a 319 I think it sounds nice but I dont have U47 to comare it too but for 116 pounds its hard to beat. all I have to compare it to is a C28A Im told same electroncs and tran as C12 with a Violet Vin 67 lollypop ( meant to sound like a U67} they sell for 400 pounds plus so I woulda thought should fairly decent, I also have a Elam 251 circuit I built that the lollypop Vin 67 goes on too & this is my best & main vocal mic....I think it sounds nice tho as I say I have nothing ready made and classic to compare it to.

Comparing the un modded Octava to the Elam job ...the Octava doesnt sound bad just different makes me want to hear the mods....& try its capsule in Elam, try its tran in Elam, try Lollypop on 319 ....well you get the picture try all combinations.....bloody mics not mine tho...bugger !

 
Rob Flinn said:
Years ago there was a site up for some guy who I think lived in the wilds in California, who managed to squash a valve into a MK219.  I can't for the life of me remember his name or the site, but I do seem to remember he was crazy about his cat, & every picture seemed to have his cat somewhere in it.

Lulu The Spacecat!

http://webpages.charter.net/altaflux/

Gary, I probably wouldn't bother with the Joly mods. Just my personal opinion... I've worked with various Oktavas, solid-state and valve, and the Oktava character will always remain for the 319 because of the capsule design. I actually quite like it.

Your easiest mod option would be the Royer Countryboy circuit (schematic at Jensen site). Other than that, there are tonnes of other circuits which would work well. Some would say to aim for something brighter sounding, but I'm happy with it as-is.
 
rodabod said:
Rob Flinn said:
Years ago there was a site up for some guy who I think lived in the wilds in California, who managed to squash a valve into a MK219.  I can't for the life of me remember his name or the site, but I do seem to remember he was crazy about his cat, & every picture seemed to have his cat somewhere in it.

I've worked with various Oktavas, solid-state and valve, and the Oktava character will always remain for the 319 because of the capsule design. I actually quite like it.

Yeah. I actually prefer the 219/319 SS than tubed ones. The stock transformer does not have a big bass response, so it nicely rounds off the lows and complimenting the capsule qualities. With tube circuits and big iron the bass can become really overpowering.

Best, M
 
The space cat thats it ha I like his sense of humour weired his DIY stuff look like mine ....Yeah I think the 319 sounds cool as is if was my mic id prob do the shortening of capsules wires mod & maybe the grill mod if I mod I like to make so I can pu back, but I do like to try things.....T14 in my Elam circuit is small ...I wonder how the 319 capsule would sound in that circuit...
Would you guys rate capsule better than most chinise .....I have no experence of chinise other than the food

Im toying with the idea of buy a 319 now as a different flavour and to DIY play with
 
gary o said:
Would you guys rate capsule better than most chinise .....I have no experence of chinise other than the food

Yeah, most of the Chinese capsules are like Chinese Buffet--all over the place...  ;D

But the Oktava is quite different and maybe closer to a ribbon kind of sound. For sure you won't have any sibilance problems.

Best, M
 
The Chinese capsules vary vastly. Although I'd say a large number of them are awful - ie. the 32mm bog-standard Shanghai model. I think it's partly how thw Chinese mics tend to get such a bad name. Some people find them useable, but I can't work with them, no matter how much filtering, etc. The 797s are nice. The edge-terminated model by SE (also skinned by Peluso) sounds nice, although bright.

The 319 capsule will always sound like a 319. Yes, you can vary the low-end to thin it down if you like, but the main character of the capsule will still remain. I would say this applies to all condenser mics in my opinion actually.
 
Funny this old thread came up just now. This monday I looked at the U47 schematic while the TV was on with news about the recession. So I thought, well, how could I possibly make the cheapest U47 type mic? The Oktava MK319, at least a good one, does have a bit of a U47 flavor - so why not put a tube circuit in there? To keep things cheap I decided to use as much of the original mic as possible while getting as close to the U47 schematic as I could with that material.

The MK-319 transformer is about 8:1, which is an okay ratio for most tube circuits, so why not re-use it? I also used the 10M and 50M resistors from the low cut circuit in series for a 60M grid to ground resistor (i.e. original U47 value). I also re-used one of the 500M resistors for a hefty low pass on the polarization voltage (the high value resistors in recent Oktavas are 500M, not 680M).

For a power suply I decided to use a Chinese one which came with a t.bone Retro tube III, a cheap tube mic I recently bought (and already modded). It puts out 120V and 6.5V.

So all I really needed exta was a 7-pin XLR plug, a handful of resistors, a 1u film resistor (I could have re-used the 1u/160V electrolytic, for maximum cheapness) and a couple smaller caps. Since space inside the mic is a little limited, I decided to use a 5840W subminiature tube. Total cost about 10-15 bucks (I actually had all the stuff lying around).

Well, built the mic and it works very well. Sounds a bit more direct and forward than my (modded) solid state MK-319; it is hardly any noisier than my (pretty quiet) solid state MK-319.

I'm no tube genius, so I  basically just tried replicate U47 values, i.e. I copied some values (1.75K cathode resistor, 100k plate resistor) and regulated voltages to U47 voltages. For some underheating I used a 4.7 ohms resistor to drop the heater voltage to about 5.9V. Initially I used a 47k resistor instead of the 30k resistor in the original U47 circuit as my supply voltage is higher. But I found that a slightly higher voltage sounds better with the 5840 tube, so I soldered another 47k in parallel (thus effectively 23.5k). Other than that, I haven't done any tweaking so far; and to be honest, I'm not sure it needs any further tweaking. It really sounds nice as is.

Anyway, it is a fairly easy and very inexpensive project. Will post pics later.
 
Hehe cool ......can we have solid state and tube A B sound files or am I pushing it now....I dont have axcess to U47 sadly.....I read it has hell of a proximity effect but in a good way so does it have big transformer for the bass & while we are here does the grill really have much difference to the sound of a mic..
 
Here's a pic. I don't think I'll have the time to do comparative soundfiles. I have an assload of work to do. I'm a freelance writer for a couple of German recording/music magazines. So I might write an article about this mod at a later point, which, if I decide to do it, would also include soundfiles.
 

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