Rode NT-1A Capsule Mod

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If the 47nF capacitor base-to-emitter of Q1, here the driver for the final transistors, were larger than the other 47nF capacitor, there would probably be attenuation at high frequencies.

http://www.douglas-self.com/ampins/dipa/dipa.htm#4

The capacitor across the bases of the output transistors is there only to clean up the fixed DC bias between the bases. Nothing more, nothing less.

The other 47nF is unlikely to be a filter anywhere within the audio range. I haven't even sim'd the circuit, but you can go ahead and see if other values affect the frequency response in any way.

https://electronics.stackexchange.c...t-switching-circuit-due-to-miller-capacitance
 
Sorry to keep piling on, but I continue to be amazed on this one. Swapped the B8 into an NT1 gen 4, sounded marginally better than stock but both were unimpressive beside the NT1A. As an aside, swapping the NT1 cap into the NT1A sounded like the NT1A stock although mine are clearly different capsule iterations.

So I swapped the B8 back into the NT1A and also added a bit of foam as KK had suggested elsewhere. I also just got a TLM 170 that I've been super excited for. Ran it through all my standard tests, then gave the NT1A another round with the foam.

The NT1A results were consistent with before. I've listened to every mic in this project next to the NT1A, including every polar pattern on the 170, and for my voice and for my tastes it is superior to all of them. I paid $27 freaking dollars for this thing and threw in a capsule I had sitting in a drawer (albeit a nice capsule).

Even stock it sounds better than several much more expensive mics in my tests, but has a recessed area (to my ears) before the rise in the high frequencies that makes it feel a bit off. Again, I hear every flaw in every other mic next to this.

It is not flat, there is still a bump in the upper range but it sounds right, natural, unhyped. The lift is balanced with the rest of the freq response so it doesn't feel as though the lift detracts or makes it have less body as can often be the case when there is a bump in the highs.

Okay, I'll stop beating this dead horse now. I just wanted to come back as I am astounded. I know there are a lot of mixed feelings on Rode, I share those mixed feelings having owned multiple K2s, NTKs, and various other mics that I've always ended up selling (though my first K2 was a favorite for a long time). This particular NT1A will remain with me henceforth.
 
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I have a pair of NT1A’s that I am planning a capsule replacement for. I have already ordered one Arienne Flat 47 from soliloqueen - I was considering trying out the Advanced Audio AK-47 for the other NT1A. However, I just spotted a Mic Parts RK47 brand new for $110 - curious as to whether any of you may prefer one over the other.

I am sticking to a less than $200 price point per capsule because I questioned whether it would be worth it to put a extremely expensive capsule into this microphone electronics No matter what mods I do, it’s safe to assume that this is not going to end up being able to compete with our Telefunken E LAM 250 or any of the other upscale microphones that we have here.
 
Couldn't be further!

Nt1a capsule is a pretty flat, cardioid-only edge-terminated capsule. RK47 is a chinese k47 with a ~5dB peak around 5kHz.

@kingkorg posted measurements some time ago.
 
Interesting. The stock model always sounds extremely bright to me.
If the stock capsule is flat, where is the extra treble coming from?
And does this contradict my theory that the capsule replacement will be an improvement?
 
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When I first mentioned capsule replacement and later mentioned eliminating some of the high treble brightness, you could probably have inferred that that would have been the improvement that I was referring to.

Your suggestion was to purchase a random, cheap capsule from AliExpress, which may or may not have any kind of quality control or consistency whatsoever. There’s nothing that would even guarantee that would capsule that I would buy there would have any relevance or minor similarity to whatever you are suggesting. Why? Because it’s AliExpress.

So I might pose your same question back to you which would be: what kind of improvement are you suggesting?
 
Your suggestion was to purchase a random, cheap capsule from AliExpress,

... Which is what the MicParts RK47 is albeit they may or may not screen out the complete duds - whether that's worth a 2-300% premium is up to you.

If it's just the brightness that bothers you (and eq in post is not an option), i'd rather look at messing with the circuit first. But that's just me...
 
... Which is what the MicParts RK47 is albeit they may or may not screen out the complete duds - whether that's worth a 2-300% premium is up to you.
Just for the heck of it, I decided to try out your suggestion of the AliExpress capsule. I searched for a K 47 capsule and selected a company that had the most buyers, hoping that would be a good indicator.

The capsule arrived today (photos 2 & 3) but it looks different than the original that is in there. it has a screw/wire terminal in the center of the capsule. I have also attached a screenshot of the RODE NT1A with its original capsule still somewhat attached. (First photo)

On the RODE, there is a red wire attached to the screw on the outer ring of the front & a yellow wire screwed into the side.
If I were to use this capsule that has just arrived from AliExpress, would I replace the connection on the red wire from the old capsule with the central wire in the new capsule?
And then just add the second wire on the side?
 

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Just for the heck of it, I decided to try out your suggestion of the AliExpress capsule. I searched for a K 47 capsule and selected a company that had the most buyers, hoping that would be a good indicator.

The capsule arrived today (photos 2 & 3) but it looks different than the original that is in there. it has a screw/wire terminal in the center of the capsule. I have also attached a screenshot of the RODE NT1A with its original capsule still somewhat attached. (First photo)

On the RODE, there is a red wire attached to the screw on the outer ring of the front & a yellow wire screwed into the side.
If I were to use this capsule that has just arrived from AliExpress, would I replace the connection on the red wire from the old capsule with the central wire in the new capsule?
And then just add the second wire on the side?
Yes
Center wire to red wire in NT1a
And the second wire(yellow) on the side
 
Just for the heck of it, I decided to try out your suggestion of the AliExpress capsule. I searched for a K 47 capsule and selected a company that had the most buyers, hoping that would be a good indicator.

The capsule arrived today (photos 2 & 3) but it looks different than the original that is in there. it has a screw/wire terminal in the center of the capsule.
can you please post the link on Ali where you bought the k47 capsule?
 
The capsule arrived today (photos 2 & 3) but it looks different than the original that is in there. it has a screw/wire terminal in the center of the capsule.

Yes it does. Except the first Rode NT1, the "hospital blue" one (which used a single-sided K67/K87-type capsule, with several variations), all the subsequent ones have used edge-terminated capsules. Edge-terminated, as opposed to center-terminated (hence the center screw and wire-tag connecting to it).
 
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