[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 just “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...just extrapolating.

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

 

[teclis22]

@Migs yeah the DIY box of doom
I read the post somewhere in the forum, that states DIY does NOT save you any money.. i am starting to think it is right ^^.

Oh can you really put in a transformer into the K2 ?!?! How ? Wich one ?!! Link me up pretty please .

 

[micolas]

@teclis22
You want to turn K2 into a completely different animal, change its DNA. Well, build another microphone, with another topology.
For K2 isn't it more practical to use a mic preamp with transformers for some Neve-style magnetic saturation, harmonics, possibly a cheaper clone, or a vst Plugin?

 

[wafelki]

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.

Hi micolas!

Yeah well, the sad and simple truth is that russian tubes are the best ;F However 50 euro each..? Seems a bit too much.

Im almost sure there is one NTK somewhere in my closet

teclis22 - Putting transformer there would be a perfect example of diy-not-saving-your-money You would probably need to seriously rebuild the mic because of little physical space... Selling it and building something or buying and modding would be much more cost effective. If you ask me - for example grab an old NT1-A and build a simple tube circuit in it. Then just buy a power supply for Tbone SCT2000, just 50 euro in Thomann. Hmm, its such a good idea I might do it myself

 

[micolas]

Hi @teclis22 !
If you want to mod or build microphones, you have so many possibilities in Germany. Search eBay Kleinanzeigen and similar local sites for some used microphone models that offer great value for money eg AKG Perception series any generation, t.boneSC450,1100,SCT800,2000, Fame Studio C 01,02,05, Behringer B2pro old model, StudioProjectsC1,etc.
So you have to look for these microphones, which have good parts, with through-hole components, not smds.
The major advantage is that you have the body, the capsule, specific parts, at an attractive price. The performances can be improved or the microphones can be platforms for other projects.

Edit:I apologize for deviating a bit from the topic of the thread, but I tried to give some good advice. DIY is full of pitfalls, temptations, obsessions, doubts, mistakes, financial costs, time-consuming, we all go through these.

 

[untamedfrontier]

Yeah well, the sad and simple truth is that russian tubes are the best ;F However 50 euro each..? Seems a bit too much.

Curious logic that 50 for a tube is too much but a potentially 200-400 capsule is not...

Even if the tube isn't a drastic improvement you'd have a spare for much cheaper than a capsule.