Rode NT1 Kit (the black one) Mods

[kingkorg]

Sure. I'm trying to figure out how i can make this mic  "better". If anyone has an idea, besides bashing it i'm open to it. I was afraid it could come to "Rode will never sound right" conclusion.

One thing to point out, keep in mind this little thing slays any vintage mic when it comes to noise. Mics are also used for voice overs, tv and radio studios, podcasts.

ASMR is a huge community and NT1 is one of the favorites. Field recording as well! A lot of classic mics wouldn't stand a chance against it, if you take that angle.

And i assure you guys, this microphone is not bright.

I was even thinking about making it a flat cardioid which can be used for measurement, or modeling. The correction curve wouldn't have to be too complex, and noise, capsule manufacture consistency are great features here.

 

[Whoops]

I have a Rode NT1000 mic and it's pretty good.
Love it on Cello, Doudle Bass and Kick Drum.

Although I don't have a Rode NT1 and don't use one for a long time, there's nothing wrong with Rode mics, there's no reason to bash them, contrary to a lot of other brands they are priced right and as you said they are used not only in music but in all audio related recording.

I'm sure the mic can be improved, but then it's a personal thing, what do you dont like? and what do you to improve?

In my experience with Rode mics, I never liked the high end, the sibilance area, similar to the way I dont like that area in Chinese mics, thats why I use my NT1000 for Bass heavy instruments that are not harsh on the top end.
I found that in all Rode condensers LDC I tried, didnt matter the model or revision.
So personally I would try to improve that

As for other characteristics they're pretty good, like you said Noise is extremely low, distortion is low also.
Most of the specs are top notch already

 

[Tim Campbell]

Well if you really want a flatter response capsule this mic is a perfect candidate. Flatter capsules tend to be noisier/quieter because of their increased damping resulting in lower output. The higher polarization voltage would compensate for that. A Neumann U89/TLM170 type capsule would be much flatter.

 

[Whoops]

Personally the high end would be the only thing I would try to improve in a Rode mic, as I find that besides that they are fine as is.

But Kingkorg might have other ideas or things he would like to improve

I wanted to mod my NT1000 with another capsule for years, to make it less sibilant but as I like it so much as is on Low End instruments I then feel there's no need for that. I found the specific uses I like that mic for.
But I may try an U89/TLM170 type capsule at some point as per your suggestion

 

[Tim Campbell]

really I think these mics really shine with a good CK12

 

[ubxf]

I heard there's a guy in Denmark that makes pretty good ones

 

[Whoops]

really I think these mics really shine with a good CK12

Sorry the ignorance, I just got into the capsules and circuits of LDC mics lately, so I'm still learning.

In what aspects would a good CK12 capsule improve on this mic?
Also what would happen in the sibilance area? or between 4K and 12K?

Thanks

 

[gyraf]

The CK12 on a NT1 more or less make the mic take post-recording EQ much better. Like there being content everywhere to be emphasized or toned down, but none of the content feels strained.

A little hard to describe, and I can say for sure that this property is NOT reflected in its measured frequency response.. CK12's are notorious for being all-over when it comes to tonal balance, yet they all share the property of eq'ing well..

And btw thanks guys. This why I love this place.

/Jakob E.

 

[Whoops]

The CK12 on a NT1 more or less make the mic take post-recording EQ much better. Like there being content everywhere to be emphasized or toned down, but none of the content feels strained.

A little hard to describe, and I can say for sure that this property is NOT reflected in its measured frequency response.. CK12's are notorious for being all-over when it comes to tonal balance, yet they all share the property of eq'ing well..

Thank you so much for your input Jakob.

What I felt from the Rode NT1 (dont know the version but used different ones over the years) and also the NT1000, and other Rode LDC I used was that I don't like the top end.
It's a subjective thing so my adjectives might not mean the same thing to you, but the way I can explain it, is not only that I find the sound (on Vocals specially) a little bit bright but specially is that I don't like the "quality" of the high end, it's an harsh high end.
It's something I never found on a U87 for example, it has high end and sibilance but it's not "ugly" in that area and the Rode mics are.
Thats my personal experience.

I remember maybe around 16 years ago when I first tried a Rode mic, it was an NT2000, I had recorded a Singer with an U87 for a track and he sounded pretty good, but some vocals needed to be redone some days after to improve the performance.
When we went in the studio to redo the vocals the U87 was not available so I tried the NT2000, same singer, same setup , same position and the sound was harsher.
The Low End, Low Mids, Mids were fine, it sounded similar to the U87 what was quite noticeable was an added "ugly" harshness between 4K and 12K that was not there with an U87 that sounded smother and with a
"Velvety" quality in the high end when compared to the NT2000.

Kick drum and Double bass don't excite the capsule in that region that much, that's why I like to use my NT1000 on those instruments. I love the Low End quality of the NT1000 and NT2000 and even the NT1.

I don't know if changing the capsule for a good CK12 would solve the problems I feel in the 4K and 12K region, I actually prefer not to use any EQ to try to solve problems in that area as I'm never as satisfied with the results as when I record it without problems there in the first place.
So taking well EQ might not be what I'm looking for.

Thanks

 

[Khron]

Well, technically, the U87 has hardware "EQ" built in, and the resulting response (if not even the capsule itself) doesn't have quite so extended response in the top end (afaik).

 

[kingkorg]

Here's a circuit mod i came up with. I had a 22mH inductor so i worked around that one. This gives the mic flat-ish response. Reminds somewhat of u67 response. Some trace cutting necessary, smd tinkering, so not very DIY friendly.

Here's before and after, and filter response curve on the top.

 

[Whoops]

Nice, would like to try that out.

How do you like the sound?

 

[Whoops]

Sorry, forgot to ask,
what do you personally would like to improve on the NT1?

 

[kingkorg]

Well, i was interested if it could get any more quiet. Yes, but it is already so quiet there is no point, the ambient or preamp noise will always be higher.

As for the sound, it sounds perfectly usable to me. Very flexible. Gearslutz people would certainly call it warm. I try not to use those terms.

Huge issue is the Rycote style capsule holder, i would just fill it out and glue it permanently. It creates terrible rumble even in a spider stand.

Maybe add a pad?

As for this filter to even out the response, i would rather do it with external eq. We came to conclusion after several experiments it's better to do it later in the chain. But for those who love to get the sound straight out from the mic, this could be an option. Or for live sound with analog mixers with limited amount of bands.


 

 

[ricardo]

kingkorg, I've just sorta returned to groupdiy and saw this awesome thread. Could you clarify a few things please.

1 The front & back responses (0 & 180) you posted in #1, what was the measuring distance?

2 I'm a bit suspicious of your before & after 'filter' responses, later in the same post. The red 'filter' responses show a return to '0dB' about 18kHz. But your before & after responses don't meet up again above 18kHz.

3 Are Q3 & associated bits also part of the 'filter'?

4 I don't quite understand #17. Is the 'Black CK12' curve, your C12 with Tim's capsule? .. the one with scooped 1.5kHz & 10kHz peak. Again, what is the measuring distance?

6 Tim Campbell, could you confirm that this is what you'd expect with your capsule on flat response electronics?

The 'Red NT1' curve appears to be the curve you posted in #1.

A simple way to deal with the 30Hz resonant Rycote mounting is simply to stuff some foam into the slot/holes. This damps the resonance. Less decoupling below resonance but the situation would still be better than solid mounting if you get the stuffing right. Just stuff it until most of the rumble goes away.

 

[kingkorg]

1. Distance for all the measurements is 40cm.

2. Edit: Now that i gave it some thought, it's entirely possible i left my reference mic compensation curve on for that circuit measurement. The curve looks right, but slight boost in the high end might come from that. So i might have messed up that one.

Btw I used a pot in place of 1.8k resistor. So i adjusted it to get flatest response, it landed at 1.8k and replaced it with a resistor.

3. Nope, its just the three resistors, inductor and the cap. The parts with large letters.

4. I have Tim's capsule in a detachable head which i can use with different bodies. This measurement is taken with a flat fet circuit with a transparent headgrille which doesn't affect sound. 40 cm again, a distance which allows me to get smooth responses (at 1m would be too far), but yet at 40cm i have no proximity effect. This is a distance used by Townsend Labs, Shure, Rode in production process QC measurements. Or so i've heard...


Lately i've been able to double check my measurement setup thanks to people from 797 audio. They sent me 2 pcs. of their capsules with measurements from their anechoic chamber. Once they arrived i measured them and curves matched 100%. Another confirmation i have is from Audio Test Kitchen. I have KSM44, KSM32, NT1, and mine measurements line up with their. I had to use Photoshop though to transform ATK measurement screenshots as they use weird scaling. I've spent about 4 years to nail the setup, and im finally 100% confident it works. I am not sure about 180° responses, there are way to many reflections there, but fine enough for approximation.

 

[ricardo]

Tim Campbell, can you confirm that the Black CK12 curve measured by Kingkorg in #37 is what you'd expect of your capsule with 'flat' electronics?

This would explain many parts of the legend of C12 & early C414 with CK12 brass capsules.

 

[ricardo]

1. Distance for all the measurements is 40cm.

2. Edit: Now that i gave it some thought, it's entirely possible i left my reference mic compensation curve on for that circuit measurement. The curve looks right, but slight boost in the high end might come from that. So i might have messed up that one.

Thanks for this Kingkorg. I take it this is with your REW setup; 1ms window above 500Hz and 10ms below. Do you have a special space to do your measurements?

I think you said you used a cardioid reference microphone? Which one and how did you get the calibration for it?

Are you allowed to post the complete circuit of the Black NT1 kit? I'm intrigued by Q3.

I'm in danger of hijacking this thread but do you think you could do a measurement of Tim's capsule in Fig-8 mode?

 

[ricardo]

One thing i noticed after listening to quite a few capsules is that beyond the frequency response there is also an impression of depth that makes a difference. What causes that ? is that due to dynamics, speed of response of the capsule.

Are you saying the Black NT1 has good impression of depth or are you referring to some other capsule/mike?

 

[kingkorg]

Thanks for this Kingkorg. I take it this is with your REW setup; 1ms window above 500Hz and 10ms below. Do you have a special space to do your measurements?

I think you said you used a cardioid reference microphone? Which one and how did you get the calibration for it?

Are you allowed to post the complete circuit of the Black NT1 kit? I'm intrigued by Q3.

I'm in danger of hijacking this thread but do you think you could do a measurement of Tim's capsule in Fig-8 mode?

Yes, it's exactly how i measured it. I use Line Audio CM4 for cardioid reference. I have also Beyerdynamic MM1 which comes with factory calibration file attached to serial number, i had also calibrated BK mic at one point. I used both of these to make calibration file for CM4. It needs just a tiny bit of correction, it could really be used with no calibration, but i did my best to make measurements as precise as possible.

This video is great resource, and they do basically the same thing i do, just that i do it without moving the mic, i use the same distance for under and above 500hz. I use both cardioid and omni ref. mics. I used cardioid for NT1.



As for the schematic, i used NT1-a schematic found in the technical documents/rode. They are basically the same.

Sadly i can't do CK12 F8, as all the mic bodies i use it with are cardioid only. I have this weird trip and don't care about using LDCs in F8 and omni. I feel no matter what i do and what capsule it is i get weird responses, and feel like diaphragms fight each other. But that's just my personal trip. I use omni capsules for omni, and ribbons for F8.