Rode NT-1A Capsule Mod

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Are you sure that there is enough space to mount the (rather high) M7 capsule + mount?
Also, Røde uses a pretty high polarisation voltage (ca. 75 V) on the capsule, do you know for certain that the capsule can withstand such a high voltage without collapsing?
 
Not sure the voltage *across* the capsule is quite that high - the JFET gate isn't quite at ground potential, but a few volts higher. About 6v, if that reverse engineered schematic is correct. That's still at the "hot" end of the 60v range though...

Iirc the JFET gate in the NT2-A sits around 12v or so.

But the height of the capsule assembly would be my primary concern too, actually.
 
Should i just go for a K47 or CK12 Capsule because of the height and voltage then?

Thank you for the Help
 
According to the information I have here, the voltage on the gate of the FET is 6.3 V.
So still a voltage of more than 60 V. between membrane and backplate.
Personally I wouldn't risk it without changing the polarisation voltage.
 

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Little Update:
I will try an build the NT-1A with a Maiku K47 Capsule.

If you know anybody who sells the Maiku pls let me know. They are really hard to find.
Thank you
 
Felix, if you are removing the original capsule and want to sell it, let me know. I have my 20 year old NT1 that has a broken capsule. I don't want to mod it or upgrade it, just want to get it working again so happy with a stock capsule. Let me know, thx
 
Hey Carnold,

I am currently trying to find a good K47 Capsule, hard to find a good vendor. I will write you asap

Greetings
 
Felix, if you are removing the original capsule and want to sell it, let me know. I have my 20 year old NT1 that has a broken capsule. I don't want to mod it or upgrade it, just want to get it working again so happy with a stock capsule. Let me know, thx
Could it be your 20yo NT1 is of the first variant and using center terminated capsule?
 
Well, I had what we in the Southern segment of the US would call a "come to Jesus moment" in regards to my mic locker last night, courtesy of this subject (i.e. capsule swap in an NT1-A).

Warning, questionable and highly subjective observations ahead!

I swapped a spare capsule I had pulled from a Blue B8 bottle cap into the NT1-A I just picked up for $27 (shipped) on eBay. It seemed absurd and gratuitous, but otherwise the capsule was just sitting in a drawer so why not. Before the swap I recorded a standardized vocal test I do with all my mics. That test suffers the common problems of re-recording vocal performances on different microphones, performances differ and regardless of controlled distances, signal chain, etc... there will always be slight environmental differences. Of course I did the same after the swap.

So, on to my subjective observations. For the before and after, before it sounded more shrill and grainy by comparison. It is not bad with the stock capsule, but subjectively ranked would definitely fall below most of the mics and capsules I've tested.

The "after" is where my whole world started to crumble. Very hyperbolic I know, but here is what happened that was so shocking. It did not have a "sound" or character of it's own. There is no magic or mojo, nothing particularly special or unique about the sound. What it did do is instantly reveal every "flaw" in every other microphone and capsule I've tested.

Even the exact same Blue B8 capsule in my Blue Bottle, along with the same capsule on a custom Blue Mouse and custom Blueberry. All of them, by comparison, have sonic oddities, anomalies, fingerprints all their own. They all impart something on the sound that when compared to the NT1-A w/ B8 is instantly identifiable. I thought my ears deceived me when I did the comparison yesterday so came back with fresh ears today and had the exact same experience.

Outside of the Bottle none of the mics compared are particularly high-end (Sony C-100, Warm WA-47, custom Blue mics mentioned above with all caps, a 251 clone, UT Twin87, and several budget mics), but all the same I did not expect this combo to add anything interesting and it did. It set a benchmark for my mic testing project that reveals the sonic signature of all the other mics. It's unlikely to become a go to mic as it is often all those "flaws" that draw me to a given mic for a given source, but it will certainly have it's uses.

That's all, sorry for that highly subjective rant, I was just a bit astonished and wanted to share.
 
Well, I had what we in the Southern segment of the US would call a "come to Jesus moment" in regards to my mic locker last night, courtesy of this subject (i.e. capsule swap in an NT1-A).

Warning, questionable and highly subjective observations ahead!

I swapped a spare capsule I had pulled from a Blue B8 bottle cap into the NT1-A I just picked up for $27 (shipped) on eBay. It seemed absurd and gratuitous, but otherwise the capsule was just sitting in a drawer so why not. Before the swap I recorded a standardized vocal test I do with all my mics. That test suffers the common problems of re-recording vocal performances on different microphones, performances differ and regardless of controlled distances, signal chain, etc... there will always be slight environmental differences. Of course I did the same after the swap.

So, on to my subjective observations. For the before and after, before it sounded more shrill and grainy by comparison. It is not bad with the stock capsule, but subjectively ranked would definitely fall below most of the mics and capsules I've tested.

The "after" is where my whole world started to crumble. Very hyperbolic I know, but here is what happened that was so shocking. It did not have a "sound" or character of it's own. There is no magic or mojo, nothing particularly special or unique about the sound. What it did do is instantly reveal every "flaw" in every other microphone and capsule I've tested.

Even the exact same Blue B8 capsule in my Blue Bottle, along with the same capsule on a custom Blue Mouse and custom Blueberry. All of them, by comparison, have sonic oddities, anomalies, fingerprints all their own. They all impart something on the sound that when compared to the NT1-A w/ B8 is instantly identifiable. I thought my ears deceived me when I did the comparison yesterday so came back with fresh ears today and had the exact same experience.

Outside of the Bottle none of the mics compared are particularly high-end (Sony C-100, Warm WA-47, custom Blue mics mentioned above with all caps, a 251 clone, UT Twin87, and several budget mics), but all the same I did not expect this combo to add anything interesting and it did. It set a benchmark for my mic testing project that reveals the sonic signature of all the other mics. It's unlikely to become a go to mic as it is often all those "flaws" that draw me to a given mic for a given source, but it will certainly have it's uses.

That's all, sorry for that highly subjective rant, I was just a bit astonished and wanted to share.
Interesting!
I also test all the capsules that pass through my hand in the NT1a, it is true with a slightly modified, expanded, enlarged headbasket.
Depending on the character of the sound, I decide on the circuit and the body in which I will install the respective capsule.
It is quite possible that Rode's circuit is very linear.
 
It's not only possible, it's a complete certainty.

https://groupdiy.com/threads/rode.61032/post-902381
So it seems from the diagram, linear, the entire audio chain is galvanically coupled, without coupling capacitors
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.
And I don't know where the 47uF electrolytic capacitors dampen the low frequencies.
In any case some measurements of the circuit response would be good.
 
It's not only possible, it's a complete certainty.

https://groupdiy.com/threads/rode.61032/post-902381
Yes, that certainly explains why it is so revealing compared to the other mic circuits I tested. This is another subjective observation (as Blue never published meaningful FR graphs of the capsules) but the B8 certainly seems the most honest of all the Blue caps to my ears. Both of which make my experience more logical and less shocking than I initially perceived it to be.

Edit: Well, ATK has it graphed and it is far from linear after 2kHz, but that is also in the Bottle circuit and with the lollipop headbasket. I suspect the headbasket has much to do with how it compares with the B8 on the other mics in addition to the circuit. The 3 Blue mics have quite different circuits but they all sound far more similar to each other than they do the NT1-A with the same capsule.

b8-nt1a.png
 
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It's not only possible, it's a complete certainty.

https://groupdiy.com/threads/rode.61032/post-902381
However, the circuit of the NT1 kit black, generation 4, is linear, as kingkorg says, but the circuit of the NT1a seems to me to have a little more treble.Are my ears playing tricks on me? Would it be possible for the difference between the polarizing voltages of the capsule, between NT1a and NT1 (black) to make a difference in the input part of the circuit?
I compared them to the same Rode capsules (from NT1a, NT1 4th, NT2-A, NT1000).
 
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