[Advice needed] Rode K2 - Capsule Replacement

[teclis22]

Hi guys,

i am new to the forum. An impressive wealth of information here. While i found a similar thread to the Rode K2, i would like to try and narrow down the question futher more.
(https://groupdiy.com/threads/rode-k2-capsule-suggestions.85520/#post-1114796)
(https://groupdiy.com/threads/best-of-the-affordable-ck12-type-capsules.56932/ )
(https://groupdiy.com/threads/hierarchy-of-edge-terminated-capsules-for-c12-251-build.75433/)
(https://gearspace.com/board/geekzone/1316017-hierarchy-edge-terminated-capsules-c12-251-build.html)
(https://gearspace.com/board/low-end-theory/823811-rode-k2-capsule-upgrade-thiersch-pvc-m7.html)

Background:
I picked up a Rode K2 over ebay with an unclear history. It is approximately 4 years old. Somewhere i read that Rode has changed capsules in the past in their production line up, but i wasnt able to find out when that actually took place time wise. So in order to get it back into good condition and - if possible - upgrade it a little, i was looking at capsule options. It needs to be said: I dont make money with audio stuff, just for fun reading fantasy themed short stories for youtube (and i am a beginner i fear)
It is my understanding Beesneez and Tim from Denmark are pretty much the top dogs but the capsules would run the same as i payed for the entire mic, and are (honestly) a bit out of my price range.

So, I would like to put the spotlight on the difference between the (cheaper) sided Capsules that are easily available (understanding they are not "real" Ck12s, but just proxies). Originally i was drawn to Advanced Audio, as i read some good things over them in general, but wasn't able to find anything specific on their AK12 capsule. Being from Europe their AK12 runs approx 140€ all in (shipping and tax). Plus - though i don't remember the exact source - i read somewhere that the AA capsule was the better choice compared to the Mic-Parts RK12 [found it, last link above], however i cannot recite an actual reason. To my understanding the AA just like the MP are all "chinese capsules" (for a lack of a better term).

In the forum i read about the "flat K47" from Arienne Audio. It would run approximately 200€ all in (shipping and tax). So between these two, wich one would you recommend?
Note: I dont do the capsule change myself. The mic goes for a "refresher" to the local small audio company and i asked them to replace the tube, mic cable and capacitators in an overhaul. So they would do the swap in the same go.

Or is there another "chinese" version or other maker (in that price braket) that i should look into?

Any information is much appreciated.

best regards

 

[Khron]

Is something wrong with the current / stock capsule in that mic?

 

[teclis22]

Hi Khron,
there is nothing wrong with it per se. It gives a tone and the patterns are working.
It just sounds... how to put this: underwhelming, maybe boring ? I dont have any measurement abilities.
Just sounds... not as "good" as i heared it sound on reviews.
Hence the refreshment treatment and its for my piece of mind knowing its as good as it can get, the rest is entirely up to my fledgling skills.

 

[wafelki]

Have you tried changing the tube? K2 is a clean, even sounding transformerless mic, maybe what you liked in those reviews was the sound of a preamp?

 

[micolas]

Hi @teclis22 !
Rode K2 is a good microphone even unmodified. It has its own character, personality. Low inherent noise, continuously varying polar patterns,having no transformer sounds very clean, almost like a jFET.
Here you can hear stock:



I replaced the stock tube with a 1975 NOS Soviet military type 6n23p-ev tube. Works great, improvements are noticeable.
The stock capsule in the K2 is similar to the one in the NT2a, it's an excellent capsule.

 

[wafelki]

Hi @teclis22 !
Rode K2 is a good microphone even unmodified. It has its own character, personality. Low inherent noise, continuously varying polar patterns,having no transformer sounds very clean, almost like a jFET.
Here you can hear stock:



I replaced the stock tube with a 1975 NOS Soviet military type 6n23p-ev tube. Works great, improvements are noticeable.
The stock capsule in the K2 is similar to the one in the NT2a, it's an excellent capsule.

Good move with that tube. Is it sharper, more detailed now? Are these 6n23p still reasonably priced in Romania btw? Something went off with their prices here in Poland... Audiophiles probably...

 

[micolas]

Good move with that tube. Is it sharper, more detailed now? Are these 6n23p still reasonably priced in Romania btw? Something went off with their prices here in Poland... Audiophiles probably...

Hi, @wafelki !
I bought some of these (for military use) several years ago brought directly from Russia. The best ones are those produced by Reflektor in the 70s...80s.
If they appear for sale here in Romania, I will announce on groupdiy.
But they are still found, for example here:

https://www.tubeampdoctor.com/en/6n23p-ev/6h23p-eb-nos/russia

With the Soviet tube, the sound became bigger, more natural, smoother, with more dimension. Maybe I'm being subjective, it's been a few years, but it's really starting to sound like a tube mic, not a solid-state.
It was modified for a friend who has a studio, very good musician.

 

[teclis22]

Dear all,
thank you very much for the feedback.
That i heared the pre-amp might very well be the case :/
I havent switched the tube yet. Wasnt sure wich one to order.
Thank you very much for the link from tube amp doc.
Going to pick that one up and post the results.

Wheee ^^

 

[Migs 31]

Hi @teclis22
I think @micolas description is the best:
“ varying polar patterns,having no transformer sounds very clean, almost like a jFET.”

I remember using it in a recording in conjonction with an AKG C-414eb at the time. And like you, I was “underwhelmed”.

Changing the Valve/Tube will change the sound a good 10/15%? (just an arbitrary number) Then changing some electronics, will give you another 5%?, then putting a transformer in, another 5/10%?, then upgrading the Capsule a good 30/40%? No one knows for sure...

Next thing you know, you opened the DIY Pandora box and spent double the money of the price of that mic. And still you think you can get “more out of it”

M