Rode NTK with NOS Telefunken 6922. Where to get tube in US?

[bluebird]

Cat 5:
can you take a couple pic of it?

Flatpicker:

yea sometimes I know I'm missing something. I new there was a small difference but I didn't want to sensationalize the mod. I think it is definitely worth the time and parts but thats just me....
thanks for taking the time to listen.

 

[Marik]

[quote author="bluebird"]
I knew there was a small difference... [/quote]

My piano teacher in Russia used to tell me: "Marik, the difference between good and great is small".
I agree with you--it was more than worth for effort, parts, and time here. Very often I spend much more for differences only I can hear (to be fair, in blind tests), and my friends tell me:" Yeah, I think it sounds better", very often just to comfort me and not to let me feel bad. :roll: :thumb:

 

[Gus]

Something I forgot to post if using higher gain tubes. The 15pf cap is used to make sure the circuit stays stable when the global feedback loop is closed. I don't know the gain of the russian 6dj8 type tube used and I don't know how far Rode went to keep the circuit stable.

One might have to increase the 15pf value with a higher gain tube.

You can still find good 12ay7/6072a tube for not to much money in the USA.

A 15 pf or so polystryene should be better than the silver mica I used but I could not find any.

 

[Gus]

yesterday 10-26-2004 I was at gearslutz and found a thread with information from Rode about tube voltages and why they picked the tube they did. I can't find it today! I forgot to save the link. Has anyone seen the thread and maybe have the link?

EDIT

Found the link I was thinking of the wrong forum.

http://www.homerecording.com/bbs/showthread.php?t=135830

 

[Category 5]

[quote author="bluebird"]Cat 5:
can you take a couple pic of it?

Flatpicker:

yea sometimes I know I'm missing something. I new there was a small difference but I didn't want to sensationalize the mod. I think it is definitely worth the time and parts but thats just me....
thanks for taking the time to listen.[/quote]

Here are some Pics

http://www.pbase.com/sbushman/image/35613075/original.jpg

http://www.pbase.com/sbushman/image/35613076/original.jpg

And fitted with the tube that titled the thread...

http://www.pbase.com/sbushman/image/35613074/original.jpg

And for fun, here is the new studio desk my Dad built for me!

http://www.pbase.com/sbushman/image/35613079/original.jpg

Shane

 

[bluebird]

Yea, on the new board there are surface mount resistors.

there are caps under the circuit board. I bet they're better ones on your circuit board than the surface mount caps Gus replaced on mine.

That tube sure does look nice.

Oh and the desk is rad!

 

[Gus]

Shane

Colors are not right on my monitor. Could you post the values and R numbers of your microphone. I wonder if they are the risitor number and value of the smd one.

 

[Category 5]

When I get a chance I will post the resistor values. Maybe Sunday I'll have some time. i am working all weekend.

Shane

 

[Gus]

Shane

Could you take a picture of the back of the board?

One of the white plastic block caps might be the one in the feedback part of the circuit. If it is you might hear an improvement with changing it to a .1uf polypro The Xicon .1uf 250V is what I used in bluebirds ntk. I don't like xicon elecros but the polypro are fine and don't cost that much.

The electros I used were nichicon low z ones from the mouser cat I would use a 330uf instead of a 220uf because it fits. The 47 at 160 don't come in low Z however the ones at mouser measured better than stock (low Z?) Hitanos.

If you can find Rubycons at 47 160 I would try them. FWIW Rubycon higher voltage caps I have tested >100V tend to measure better than other good brands. Mouser did carry them in the past but i can seem to find them now. I have a few rubycon 47 at 250 that have 1/2 the ESR of the stock Hitanos but they don't fit in the NTK.

Maybe you can try the Mod Bluebird did to use a 12ay7/6072a

To be clear I am thinking of maybe selling a kit of parts to upgrade the NTK/K2 as well as other microphones based on my own work. Do you people think there could be a market for this?

 

[Bri]

Hey guys...finally found this place(thanks to CJ).
Just came across this thread. I remember asking about modding the NTK back when "Tech Talk" existed. Lot's of great info here. I just wanted to say I appreciate all your efforts...Gus, Bluebird, etc.

Gus, in regards to a market for an NTK mod kit, since I'm still a novice, someone like me would be interested in an upgrade kit...is that market enough? :wink: :guinness:

--Brian