Lowering self-noise of Sennheiser e614? (Bought CM4’s instead)

[svyet]

Update: I’m committing to a pair of CM4’s based on all the recommendations, and as I have immediate and consistent use for them, but the 8040’s and 8050’s are just too far out of my reach and justification right now. I emailed Line Audio with a question on Thursday regarding a stereo pair, but so far no reply. Searched the forum, but no answer found. Maybe someone here in the forum has enough experience with these mics (and/or communicating with Line Audio) to answer this question. @kingkorg I know you have at least four CM4’s based on a February 2022 post, and you really seem to trust them.

My question: is it possible to order a matched stereo pair, or are these mics consistent enough to use any two as a stereo pair without much tweaking?

If they are consistent enough to simply order two from anywhere, I’ve read that No Hype Audio ships fast to the U.S., as opposed to dealing with Line Audio directly? Or is there little difference? I want to receive them quickly, but not at the expense of doing the “right thing” if the purpose is to also support Line Audio’s work.

Thanks in advance—

 

[kingkorg]

I have several of these, manufactured and bought at different periods, i even disassembled one of these to the tiniest parts to lift the schematic, and check what they've done with the capsule, after re-assembly all of them measured and sounded within a db from each other. I'd say just pull the trigger, you'll thank me later

 

[Icantthinkofaname]

Update: I’m committing to a pair of CM4’s based on all the recommendations, and as I have immediate and consistent use for them, but the 8040’s and 8050’s are just too far out of my reach and justification right now. I emailed Line Audio with a question on Thursday regarding a stereo pair, but so far no reply. Searched the forum, but no answer found. Maybe someone here in the forum has enough experience with these mics (and/or communicating with Line Audio) to answer this question. @kingkorg I know you have at least four CM4’s based on a February 2022 post, and you really seem to trust them.

My question: is it possible to order a matched stereo pair, or are these mics consistent enough to use any two as a stereo pair without much tweaking?

If they are consistent enough to simply order two from anywhere, I’ve read that No Hype Audio ships fast to the U.S., as opposed to dealing with Line Audio directly? Or is there little difference? I want to receive them quickly, but not at the expense of doing the “right thing” if the purpose is to also support Line Audio’s work.

Thanks in advance—

They really are great if you need cardioids. There's potentially a hypercardioid coming down the line, right now they're swamped with building the CM4 and Omni1 orders. I haven't measured mine but mine sound really close to me, probably closer than some "matched" mics I've used.

 

[svyet]

That's all great news. I guess it's settled then!

I'm pretty excited, because the same week I came here with the e614 question and not knowing whether or not I even need a different SDC (nevermind two), I asked a friend of mine yesterday out of pure curiousity if anyone was recording their group's orchestral concerts. They said a local tv station will usually tape them, but audio is terrible, captured only by some old overheads. I smelled blood (haha) and offered to record for free to get some practice in, but I need a good pair of cardioids first - enter the CM4's. The price seems like a joke really.

I'll take it as divine providence given the timing, especially as this could very well work into some extra income in the future for my family once I'm confident enough to start charging

Doing more research on live stereo recording in the meantime.

Thank you guys again for the suggestions and confirmation!

 

[xeawr]

I've used CM3s, CM4s (and OM1s) a lot.

Lovely mics, relaxed cardioid pattern, good resolution, nice sound, no noticeable noise issues (used them along LDC mics with 12-16 dbA self noise - they blended right in). I would record a whole album with those if I had to (think "desert island status").

The only gripe I have is they don't take EQ too well, but maybe that's too much to ask for (for the price).

Cheers!

 

[svyet]

I've used CM3s, CM4s (and OM1s) a lot.

Lovely mics, relaxed cardioid pattern, good resolution, nice sound, no noticeable noise issues (used them along LDC mics with 12-16 dbA self noise - they blended right in). I would record a whole album with those if I had to (think "desert island status").

The only gripe I have is they don't take EQ too well, but maybe that's too much to ask for (for the price).

Cheers!

Thank you for all of that.

Would you mind elaborating on them not taking EQ well? Do you mean even for small sweetening adjustments, or only for large corrective adjustments? Are you talking about all three mics in general, or specifically the CM4? I bought the CM4’s given their neutrality, which for me usually implies more flexibility in post than if they are colored and potentially require larger adjustments.

Thanks!

 

[kingkorg]

I personally haven't had anny issues with eq. Maybe due to the fact they are flat, one might want to approach eqing differently than "regular" colored mics. I like to apply dozens of different IR curves of various mics i've measured and collected during the years. Use it as a kind of modeling mic.

 

[svyet]

I personally haven't had anny issues with eq. Maybe due to the fact they are flat, one might want to approach eqing differently than "regular" colored mics. I like to apply dozens of different IR curves of various mics i've measured and collected during the years. Use it as a kind of modeling mic.

Yeah, that’s really clever, and one reason I bought the black NT1 a couple years ago. Not necessarily for IR in my case, but for the flexibility (but now that you mention it, that would be an excellent philosophy of use for the black NT1 as well). That was the same rationale for the CM4’s based on your suggestions and the flat response. Flexibility and adaptability. By the way, the guy from No Hype was an absolute pleasure to deal with. Super communicator.

I've used CM3s, CM4s (and OM1s) a lot.

Lovely mics, relaxed cardioid pattern, good resolution, nice sound, no noticeable noise issues (used them along LDC mics with 12-16 dbA self noise - they blended right in). I would record a whole album with those if I had to (think "desert island status").

The only gripe I have is they don't take EQ too well, but maybe that's too much to ask for (for the price).

Cheers!

My original questions from post #26 remain, with the addition of some questions specifically regarding EQ in post:

- could it be the actual equalizer that you have issues with (outboard? Plug-ins?)
- how extreme were you correcting in terms of dB’s at any given frequency?
- could it be room conditions that influence your ability to correct the EQ to your liking? (weird filtering, room reflections, etc.)
- would an equalizer with linear phase alleviate some of the problem you experienced (especially when making larger or more precise frequency corrections?)

I’m trying to understand any potential mic-specific problems to avoid, if in fact they exist, aside from the typical recording and post-production things to be aware of. But as it stands, my understanding is that if the mic is neutral, it should take EQ much better than any colored mic (at least compared to the frequencies that are already colored to any extreme), assuming all other factors are taken into account (environment, mic placement, quality recorder and preamps, good equalizer, linear phase when needed, etc.)

Cheers—

 

[kingkorg]

Yeah, that’s really clever, and one reason I bought the black NT1 a couple years ago. Not necessarily for IR in my case, but for the flexibility (but now that you mention it, that would be an excellent philosophy of use for the black NT1 as well). That was the same rationale for the CM4’s based on your suggestions and the flat response. Flexibility and adaptability. By the way, the guy from No Hype was an absolute pleasure to deal with. Super communicator.

I had an idea a while ago. Since the black NT1 is crazy consistent, and the response can be easily flattened with a simple eq curve, i wanted to pitch the idea to a free plugin developer guy and provide him the curves to make a freeware modeling plugin that can be used with otherwise transparent, consistent, inexpensive, silent readily available NT1. However for whatever reason i never got to it. Not saying modeling mics can replace the originals, but i've had tremendous success playing with Slate and TL Sphere, also knockoffs of both i made myself. The NT1 would most certainly be better platform for this compared to the ML1.

If you are interested i can share the correction curve for the black NT1 that can be loaded in Voxengo CurveEQ, or make an IR.

 

[svyet]

I had an idea a while ago. Since the black NT1 is crazy consistent, and the response can be easily flattened with a simple eq curve, i wanted to pitch the idea to a free plugin developer guy and provide him the curves to make a freeware modeling plugin that can be used with otherwise transparent, consistent, inexpensive, silent readily available NT1. However for whatever reason i never got to it. Not saying modeling mics can replace the originals, but i've had tremendous success playing with Slate and TL Sphere, also knockoffs of both i made myself. The NT1 would most certainly be better platform for this compared to the ML1.

If you are interested i can share the correction curve for the black NT1 that can be loaded in Voxengo CurveEQ, or make an IR.

That's a great idea, and very generous of you! And I'm sure Rode would love anything that would help sell more black NT1's haha..

I don't have enough of an immediate use for the curve and IR's, and I also don't have CurveEQ (can't justify $80 for it either). However, I'd certainly wait for a plugin, and I'd be happy to help you see that through.

Who did you have in mind for a developer? Underneath, it would seem simple enough, utilizing a baked in correction curve for the black NT1 (might be helpful to test a few more NT1's to generate an average curve?) with a selection mechanism that loads and displays the different IR's (which I assume could also be baked into the plugin as opposed to a separate folder?). If you were to keep the selection boiled down to a handful of select classic mics, it might be nice to have a GUI with a vintage vibe and small array of backlit push buttons. I foresee most people with a black NT1 (or really anyone) being primarily interested in at least simulating other LDC's, and obviously the most famous ones like U87, U67, TLM103, etc., so that could help keep the selection focused and tidy. In any case, I think GUI should be attractive but simple, and definitely uncluttered. There would probably be room in the future for "upgrading" the GUI, but I think most plugins are ugly and cluttered, even for simple stuff. Slate and TL feel too busy. I can help put together a "mood board" and general layout to eventually get a designer involved.

Either that or keep it entirely utilitarian with a simple drop down menu. For a general idea of that kind of option, I made a super-rough proof of concept by taking a quick screenshot of the drop down section of a very basic IR loader, cleaned it up, and put a gold title on top for NT1 vibe. It should look much nicer than this. This would also assume the IR's are baked into the plugin as opposed to separate wav files. Something like this is probably the most feasible, and gets the job done in any case. However, GUI itself is something that only needs to be designed once (for the most part). So you could keep a simple functionality, but still have a pleasant GUI to look at, like something with back-lit analog push buttons, etc.

General thoughts? Should we continue this under the NT1 thread?

EDIT: redid the attached mockup and replaced the previous one. I'll work on some nicer mockups to reflect the analog push-button idea when I have some time in the next couple of days.

 

[JW]

Is off axis sound good with the CM4 mics? Subjective I know, but curious about the blend between say, vocal mic (?) and CM4 on acoustic guitar, like behind the bridge.

 

[kingkorg]

Is off axis sound good with the CM4 mics? Subjective I know, but curious about the blend between say, vocal mic (?) and CM4 on acoustic guitar, like behind the bridge.

It's exceptional according to my measurements. HF response just gradually falls off when you move towards 180°, no crazy peaks anywhere, not even at 180°.

 

[ccaudle]

It's exceptional according to my measurements

That's pretty unusual for a low cost microphone. Do you know the heritage of the capsules used?

 

[kingkorg]

Primo EM200, but it is modified to the point that it has nothing in common with the original capsule. Tuned, and measured individually. I have even bought some em200 (em204 as well) and got nowhere near the desired result. Chamber back the capsule is custom, and the hole pattern visible from the cm4 front impacts the sound tremendously. The hole pattern of the capsule is changed as well. The circuitry of the mic is very unique as well. Having in mind the price of the capsule (40$ish) it makes no sense to even try. Roger (Line Audio) is absolutely insane, and so are all of his products.

 

[xeawr]

Thank you for all of that.

Would you mind elaborating on them not taking EQ well? Do you mean even for small sweetening adjustments, or only for large corrective adjustments? Are you talking about all three mics in general, or specifically the CM4? I bought the CM4’s given their neutrality, which for me usually implies more flexibility in post than if they are colored and potentially require larger adjustments.

Thanks!

Hi!
I can give you a practical example of what has happened to me a number of times: I record cello for instance with the CM4 and a UM70S and say, a 414EB and later find out that I like the sound of the CM4s a lot, so I decide to go with them for mixing. I then start to apply normal amounts of compression and corrective EQ (pop mix) and all of a sudden they bring out a harsh quality that is not present with Schoeps, KM184 etc (or of course the UM70S or the C414EB). It seems like the sound falls apart. It's something I call "resolution" - "how much signal is really behind what you can hear?"

I recorded guitar, cello, violin, vocals, ukulele, shaker, organ, misc orchestra duties and other instruments with them. I like them - no I LOVE em, but because of the aforementioned phenomenon I now use them only when I know I want to use their natural clean sound (in the mix).

The U87Ai (to me) is (one of many) perfect examples of a mic that you can just put up there and then later adjust to your liking. However that's not good practice if you plan doing it that way.


Keep in mind ears are different. While I don't hear "everything", I'm pretty sensitive when it comes to the subtleties I notice/hear in my recording equipment, chain, studio etc.

 

[xeawr]

Yeah, that’s really clever, and one reason I bought the black NT1 a couple years ago. Not necessarily for IR in my case, but for the flexibility (but now that you mention it, that would be an excellent philosophy of use for the black NT1 as well). That was the same rationale for the CM4’s based on your suggestions and the flat response. Flexibility and adaptability. By the way, the guy from No Hype was an absolute pleasure to deal with. Super communicator.



My original questions from post #26 remain, with the addition of some questions specifically regarding EQ in post:

- could it be the actual equalizer that you have issues with (outboard? Plug-ins?)
- how extreme were you correcting in terms of dB’s at any given frequency?
- could it be room conditions that influence your ability to correct the EQ to your liking? (weird filtering, room reflections, etc.)
- would an equalizer with linear phase alleviate some of the problem you experienced (especially when making larger or more precise frequency corrections?)

I’m trying to understand any potential mic-specific problems to avoid, if in fact they exist, aside from the typical recording and post-production things to be aware of. But as it stands, my understanding is that if the mic is neutral, it should take EQ much better than any colored mic (at least compared to the frequencies that are already colored to any extreme), assuming all other factors are taken into account (environment, mic placement, quality recorder and preamps, good equalizer, linear phase when needed, etc.)

Cheers—

Hi Svyet,

the EQ is fine (ITB). I had these results after recording (and mixing) in a professionally built studio, but I can reproduce this phenomenon at home if I want to. It's simple and obvious, BUT it's nothing to lose sleep over if you only apply moderate amounts of EQ.
The EQ that I applied was something in the magnitude of +- 6 to 9dB with a high Q, corrective EQing, maybe a couple of bands, (say, to remove unwanted resonances from close micing an acoustical instrument, or really polishing up a vocal track).

If you want to get good SDC mics, get these. Basically everything I have heard up to say 300 Euros or maybe more (a piece) is equal or worse. While (to me) there are good cheap LDC options, for SDC I keep coming back the known brands and models.

Boy, I'm probably too picky, I should probably just grab a 58 and use it for a couple of weeks...

Cheers!

 

[Icantthinkofaname]

Hi!
I can give you a practical example of what has happened to me a number of times: I record cello for instance with the CM4 and a UM70S and say, a 414EB and later find out that I like the sound of the CM4s a lot, so I decide to go with them for mixing. I then start to apply normal amounts of compression and corrective EQ (pop mix) and all of a sudden they bring out a harsh quality that is not present with Schoeps, KM184 etc (or of course the UM70S or the C414EB). It seems like the sound falls apart. It's something I call "resolution" - "how much signal is really behind what you can hear?"

I recorded guitar, cello, violin, vocals, ukulele, shaker, organ, misc orchestra duties and other instruments with them. I like them - no I LOVE em, but because of the aforementioned phenomenon I now only use them when I now I want to use their natural clean sound in the mix.

The U87Ai (to me) is (one of many) perfect examples of a mic that you can just put up there and then later adjust to your liking. However that's not good practice if you plan doing it that way.


Keep in mind ears are different. While I don't hear "everything", I'm pretty sensitive when it comes to the subtleties I notice/hear in my recording equipment, chain, studio etc.

Have you tried applying 2-3 extra dB on the CM4? Because they're supposed to be ruler flat, meaning they should by flatter than a U87ai. I actually just got a pair of AT4053bs, which are noticeably flatter than my Oktavas, but I don't hear a noticeable difference aside from that. Of course a U87ai will sound different from a CM4 because it's a large diaphragm mic with a transformer, but if you EQ the two with cardioid pattern recordings, to the same boosts (including matching the CM4 to the U87ai's existing boost) I think you'd find the CM4 is really good. I don't have a U87ai or C414 EB to compare it too, I just have the C414 B-ULS, but I wouldn't consider an SDC like the CM4 to be worse because of the different sound.

Before making any conclusions I would grab something like a Schoeps MK4 or the wide cardioid capsule (ideally with a slightly older body like the CMC5) and throw it and the CM4 on the exact same performance, spaced the same, then gain match them and compare raw and EQ'd samples.

I suspect my AT4053bs will be closer to my MK-012s on my Zoom F6 than a CM4 will be to a Schoeps, but I also have a hard time imagining the CM4 will take EQ any worse than another cardioid mic (assuming both are similarly positioned and on axis).

 

[svyet]

Hi Svyet,

the EQ is fine (ITB). I had these results after recording (and mixing) in a professionally built studio, but I can reproduce this phenomenon at home if I want to. It's simple and obvious, BUT it's nothing to lose sleep over if you only apply moderate amounts of EQ.
The EQ that I applied was something in the magnitude of +- 6 to 9dB with a high Q, corrective EQing, maybe a couple of bands, (say, to remove unwanted resonances from close micing an acoustical instrument, or really polishing up a vocal track).

If you want to get good SDC mics, get these. Basically everything I have heard up to say 300 Euros or maybe more (a piece) is equal or worse. While (to me) there are good cheap LDC options, for SDC I keep coming back the known brands and models.

Boy, I'm probably too picky, I should probably just grab a 58 and use it for a couple of weeks...

Cheers!

I appreciate the clarification! Certainly, I won't lose sleep if the scenario you described (+-6 to 9dB, high Q) is the worry. I think that is well outside of my intended use for these mics anyway, which is more in the realm of organic ambience for video and the occasional concert recording (just for experience) with no real intent of EQ'ing if not necessary. High/low cuts and a light touch of compression will typically do. For anything vocals or instruments that might need a heavier touch of EQ, I'd be using the black NT1, so that's no problem.

I do have a question for you in terms of EQ, particularly in a heavier correction, high Q scenario: have you tried using an equalizer with linear phase to alleviate the abnormalities that can come from such correction? I'd be interested to know if that makes a difference for you. That's not to say it's a fix-all. I've heard a great case for deciding on linear phase on a case-by-case basis, as one is not always better than the other in some cases. Just different. I guess in some cases, abnormalities from heavy EQ without linear phase might actually produce more desirable results. Our ears tend to like certain kinds of distortion sometimes. But if clarity is the goal, it's my understanding that for heavy adjustments, linear phase can help alleviate the resulting aforementioned abnormalities. Correct me if I'm wrong.

And yes, the only reason I don't use an SM58 (or SM57) is because I don't have a need for a dynamic. At least not yet!

 

[xeawr]

but I also have a hard time imagining the CM4 will take EQ any worse than another cardioid mic (assuming both are similarly positioned and on axis).

Dear friends,

"your mileage may vary" as they say. When helping new engineers or amateurs that get into recording and mixing I always advise them to listen to their judgement, as it helps developing their hearing. They need to establish personal reference points and train their ears so that in the future they can evaluate (acoustic/sound) material.
Because of this we all hear things differently, which is perfectly fine. We also access microphones (= tools) differently, as we all have a different workflow and approach to the art and craft of sound/music production.

It is well known, that some microphones take EQ better than others. Not all flat SDC cardioid mics sound the same.
Those that have extensively worked with many different mics can attest to the fact that the frequency response graph gives only a vague idea of what the sound of a mic will be like, and usually mics are not being selected for specific applications because of their FR graphs, but other reasons, often described by those unpopular unscientific terms such as "detail, smoothness, resolution" etc.

So as for the CM4, I've already described my findings with them. When I still used them a lot I was using Fabfilter EQ in Linear Phase Mode (usually Medium setting). It's my standard for corrective, uncolored EQing.

The CM4 are superb mics, and Roger has been more than friendly, helpful and professional when I had to call him or contact him by email. You can't go wrong with any of his stuff really!

Cheers

 

[Mellow Audio]

Yeah,
Check the zeners for sure.
Sometimes over heating components can cause this.