Topic: [DPA 4061 users] A few questions about SPL and modding possibilities

[fandelive]

Hi everyone,

I've taped a whole bunch of hard-rock shows within the last few years using a pair of 4.7k modded MM-HLSC-1's and I have been thrilled with the results.
Point is that I'd like to enjoy concerts from front rows and I want to be able to move my head a bit more (mics are usually mounted to a hat). Also, a bit more bass in the mix would be welcome.

So I'm considering buying a pair of miniature omnidirectional mics. The DPA 4061's seems to be a taperssection's users favourite.

I have a few questions thought :

1) I tape mainly hard rock bands in club-type venues (and sometimes arenas too). That means the mics have to handle loud SPL.
My MM-HLSC's had to be 4.7k modded to be able to handle high SPLs, even if the specs were announcing a 138dB threshold when powered with a battery-box (which I did use). That wasn't true, trust me.
Will I have to apply the mod to the DPAs too (134dB SPL threshold) ?

The DPA 4060 are said to be able to handle a 124dB SPL. I know they'll get me brickwalling results with the kind of shows I'm attending.
I've heard brickwalled tapes made with them. 4061 are only handling 10dB more SPL...

2) Does high-sens and low-sens mics have something to do with the SPL ? Or is it a whole different thing ?

3) I plan on purchasing the mics from another reseller than Core Sounds. That means I'll get 2 separated single point mics terminated with microdot plugs.
I have a Chruch Audio CA-9100 preamp which I'd like to use with the mics. This preamp has one stereo mini-jack input.
Is it possible to merge both single points mics to a single "Y" pair of mics terminated with one single cable and a stereo mini-jack plug ?

So my rig would be : DPA 4061 > CA-9100 > Edirol R09-HR (line in).

4) Which forum user would be able to mod the mics for me ? I'm thinking about Darktrain; I might send him a PM.

Thanks,
-Frank

[jlykos]

I use 4061s to tape a lot of metal and hard rock shows and have never approached clipping the microphones. In fact, I usually need to turn the gain on the recorder pretty high. It's different from my old pair of Sonic Studios microphones, which were excellent sounding mics, but clipped like crazy at high shows.

Yes, you can use them with a Church Audio preamp; in fact, that's what I am using right now. Chris Church modified the mics to a single Y-cable that plugs into the 1/8" input on the CA preamp. It's a good system because the CA allows you to add plenty of clean gain to the mics if you find yourself taping quieter shows. I figure that plenty of people on here can rewire the mics if you don't feel like sending them to Canada.

[adrianf74]

I figure that plenty of people on here can rewire the mics if you don't feel like sending them to Canada.

Darktrain did a great job on the pair of 4061's that I have.  I'll also add that the 4061's have never overloaded on me.  I think the only time somebody's done that is at a Mogwai show and they hand out earplugs at their shows. 

[fandelive]

I use 4061s to tape a lot of metal and hard rock shows and have never approached clipping the microphones. In fact, I usually need to turn the gain on the recorder pretty high.

Even when taping from the first row and/or doing stack taping ?

[DSatz]

Let's try to establish a sense of proportion here. 134 dB SPL is so very loud that you would not--could not--stay in a room where it was happening. You would soon be driven into such a high state of stress that you could well have a heart attack and die.

A pressure transducer (which these mikes evidently are) with a 134 dB maximum SPL specification could be placed 1" in front of the mouth of the loudest opera singer the world has ever known, and it wouldn't overload. You could put it in the bell of a trumpet or trombone, and at the loudest end of a professional player's ability it would occasionally clip--but if you backed it away a foot or more, the problem would be solved.

That's really what these extreme specifications are about: very close placement to exceptionally loud sound sources. Not 40 feet or 10 feet or even 2 feet away from a P.A. loudspeaker--because to produce 130+ dB SPL at those miking distances, the original sound would have to be so loud that everyone anywhere near the speakers would have permanent hearing loss within a fairly short time.

> The DPA 4060 are said to be able to handle a 124dB SPL. I know they'll get me brickwalling results with the kind of shows I'm attending.
> I've heard brickwalled tapes made with them. 4061 are only handling 10dB more SPL...

This way of looking at things overlooks some basic points.

(1) Condenser microphone capsules are virtually unclippable by any real-world musical sound that human beings would tolerate for five seconds; it's the electronics of the microphone that reach their limit at the specified levels. But maximum SPL specifications are based on the specified method and voltage for powering the microphone, and apply only when the microphone is connected to an input with the minimum specified impedance or greater. If you use modified powering, modified microphone circuitry, or if you're feeding recorder inputs that have lower impedance than the manufacturer specifies, the specs go out the window; you'll have to remeasure the maximum SPL of your non-standard arrangement as a whole.

(2) Even if standard conditions for the microphones are completely met, with consumer-grade recording equipment the main risk of overload isn't in the microphones--it's the input circuit of the recorder or preamp. This is why attenuators exist. When a live recording has distortion from overloading but the meters on the recorder never got to 0 dB, the first thing to try is a resistive pad at the input of the recorder. If the distortion goes away, you have your diagnosis and your solution right there.

--best regards

[ilduclo]

I use 4061s to tape a lot of metal and hard rock shows and have never approached clipping the microphones. In fact, I usually need to turn the gain on the recorder pretty high.

Even when taping from the first row and/or doing stack taping ?

yes, in my experience, the dpa's have never gone over for me. right next to the stacks for the Melvins, Mascis and Mike Watt.

[Gutbucket]

(2) Even if standard conditions for the microphones are completely met, with consumer-grade recording equipment the main risk of overload isn't in the microphones--it's the input circuit of the recorder or preamp.

^^
In my opinion, not all, but many reports of 4060 clipping on concert recordings is actually due to this.  The sensitivity difference between 4060 (20 mV/Pa) and 4061 (6 mV/Pa) [edit- in consideration with the flat low-frequency response of these pressure-omnis] seems more significant to me than the difference between the max SPL before clipping figures for most concert recording.

In practical terms, my own assessment of appropriate applications for the 4060 verses 4061 primarily considers their differences in sensitivity and self-noise:

4060- significantly more sensitive (hotter output), quiet enough for classical material I record in quiet halls with silent audiences, where the noise floor of the recording is still that of the room, not the self-noise of the microphone.

4061- less sensitive and a better match for louder, amplified material (less hot output), plenty quiet enough for the venues and musical styles you mention, but not quiet enough for silent audiences in good halls, where the noise floor of the recording will be determined by the self-noise of the microphone.

4062- reportedly has been used to record professional racecar engines under the hood.

I expect, but can't guarantee that the 4061 will be appropriate for your uses.  For what you are recording, it's self-noise should not be an issue.  The 4062 (1mv/PA) would unquestionably not clip, but its self-noise could be an issue.  From the specifications, the increase in self-noise going from 4061 to 4062 is significantly larger than the difference between the 4060 and 4061, but I've never used a 4062 so I have no subjective reference for how noisy it actually is.

[Gutbucket]

You either need to chop off the microdot connectors and re-terminate to a single stereo mini-plug (simplest answer), or have a custom 'Y' cable built with a stereo mini and two female microdots or two male dots + threaded microdot barrel connectors.  An off-the-shelf 'Y' cable like that does not exist.

If you decide to chop the dots, please consider leaving enough cable on them so that they can be re-used (at least a couple inches, the more the better) and sending them my way.  I can use them, thanks.

[ilduclo]

I record a lot of quiet shows with 4061's and have no problems with "mic noise". Maybe I have different hearing than others, but I think they are all around great mics

[adrianf74]

I record a lot of quiet shows with 4061's and have no problems with "mic noise". Maybe I have different hearing than others, but I think they are all around great mics

It all depends on how far back you are from the stacks as well as how the mics are placed in a room.  I've encountered some extra hiss in situations where recorded levels were peaking around -28 on my recorder as it was simply an artist and guitar (played quietly) without a band before the band came out.   I've also heard onstage mic noise through PA's (even in the BEST sounding rooms -- this happened most recent at a solo singer-piano based show I just saw in one of the world's best sounding room).

4061's are _THAT_ good that they'll pick up the good and the warts and all.

[Len Moskowitz (Core Sound)]

Jon Stoppable, DSatz and Gutbucket posted lots of good advice.

The 4061s are the correct capsule for what and where you're recording. You can add a simple and low-cost attentuator cable if you're really recording over 134 dB SPL, but I really doubt that will ever happen.

One caution: The capsules are easily destroyed if you put too much voltage on them, so be sure that the limiting resistor is correct for the voltage that you're using.

One other note: Finding a pair of well-matched capsules is absolutely not guaranteed by having serial numbers close to each other. We've tested hundreds of 4060s and 4061s (and even a few 4062s), and it's really true.

And we can make that dual micro-dot-F to 1/8" stereo plug cable adapter for you. Please contact us for pricing.

[fmaderjr]

The DPA 4060 are said to be able to handle a 124dB SPL. I know they'll get me brickwalling results with the kind of shows I'm attending.
I've heard brickwalled tapes made with them. 4061 are only handling 10dB more SPL...

No the 4060's will handle 134 dB SPL and the 4061's 144 dB.

The 4061's are almost impossible to overload.
The 4060's are a bit better for acoustic and much better for very quiet stuff (due to lower noise floor) but also do well recording very loud stuff unless you are recording insanely loud shows near the stacks. Then they could overload.

You would surely have no worries with 4061's.

[yates7592]

The DPA 4060 are said to be able to handle a 124dB SPL. I know they'll get me brickwalling results with the kind of shows I'm attending.
I've heard brickwalled tapes made with them. 4061 are only handling 10dB more SPL...

No the 4060's will handle 134 dB SPL and the 4061's 144 dB.

The 4061's are almost impossible to overload.
The 4060's are a bit better for acoustic and much better for very quiet stuff (due to lower noise floor) but also do well recording very loud stuff unless you are recording insanely loud shows near the stacks. Then they could overload.

You would surely have no worries with 4061's.

The 134/144dB figures for 4060/4061 are max values when using 48V phantom power. When supplying 5V or so they will be closer to the 124/134dB figures previously suggested (134dB is still plenty of course). As others mentioned, the bigger issue with 4060 is that it puts out a much hotter signal so with very loud music you can run the risk of overloading your downstream pre / recorder.

[yousef]

The 134/144dB figures for 4060/4061 are max values when using 48V phantom power. When supplying 5V or so they will be closer to the 124/134dB figures previously suggested (134dB is still plenty of course).

Surely not - if you apply 48v to these mics without something to step it down to single figures you'll release that magic smoke that makes them sound so good.

I was initially a bit edgy about using even a 9v supply on my 4060s.

DPA does make some adaptors that would allow use with a 48v supply but presumably these serve only to bring that voltage down to the 5v that the mics require, I can't imagine that they would bring any advantage in terms of  maximum SPL.

[yates7592]

@ Yousef - see the attached, table at bottom of p.2 "changes in specification if you supply less than 48V phantom power" - is this not suggesting what I said, or have I misunderstood something? (quite possible):

http://images.thomann.de/pics/prod/176428_manual.pdf

[Gutbucket]

@ Yousef - see the attached, table at bottom of p.2 "changes in specification if you supply less than 48V phantom power" - is this not suggesting what I said, or have I misunderstood something? (quite possible):

http://images.thomann.de/pics/prod/176428_manual.pdf

That's through the DAD6001 adapter.  When properly powered with 48V phantom power, the output of the adapter to the microphone itself is 5V.

[yates7592]

Yes, I can understand that, so  what is that table actually telling us about the apparent variation in max spl of 4061?

[Gutbucket]

That the output voltage of the DAD6001 adapter varies with input voltage.  As phantom power voltage into the adapter is reduced, the stepped-down output voltage to the microphone is also reduced.  And as the mic's supply voltage is reduced, self-noise increases and max SPL is decreased.

One would need to measure the actual output voltage of the DAD6001 adapter under those varying input phantom voltages to determine what actual mic power voltages correspond to the figures in the table.  Too bad they don't list that in another row along the bottom of the table, as it would apply to any powering scheme for the microphone and not just the DAD6001.

[ilduclo]

9v works great w/4061's

[Len Moskowitz (Core Sound)]

Even slightly too much voltage (e.g., 9.6 V) can destroy a 4061. Some of the newer batteries (not the old alkalines) can hit those voltages.

Be careful out there!

[beatkilla]

Even slightly too much voltage (e.g., 9.6 V) can destroy a 4061. Some of the newer batteries (not the old alkalines) can hit those voltages.

Be careful out there!

Can you tell me what the voltage supplied that the DPA 4061 on your Mic2496 v2?

[Gutbucket]

Safe range for full spec performance with most of the miniature DPAs is between 5V and about ~10V 9V or so to the microphone.  Standard 9V battery boxes or preamp supplies fall in that range.  Higher voltage risks damaging the FET whereas lower voltage limits performance as noted previously (it's just not well quantified below 5V). 

4063 is the exception.  Its a lower supply voltage omni which works to specification down to 3V (same sensitivity as 4061).  Not sure if it also has a lower limit above which the FET is at risk.

Len posted while I was typing, he knows these mics well.  Safest to keep it below 9.6V on his recommendation.  Last I checked, my primary powering schemes for them provide around 8V.

[Len Moskowitz (Core Sound)]

In our experience, 10 Volts, without correct current limiting, will almost certainly destroy the capsules.

[Len Moskowitz (Core Sound)]

Can you tell me what the voltage supplied that the DPA 4061 on your Mic2496 v2?

9 Volts through a 13k resistor.

[audBall]

Just an anecdotal note that I have run the 406x with the SP-SPSB-10 battery box supplying 12v.

In an email exchange with DPA, they told me that "12v should be fine...when you go above 15v you want to use the DAD6001 adapter".

Did I receive incorrect info from them?

[Len Moskowitz (Core Sound)]

It depends on the value of the current limiting resistor, which also drops the voltage at the capsule.

If you connected the capsule directly to 12 Volts, with no limiting resistor, you'd have a very dead capsule.

[MBHOTAPER]

Let's try to establish a sense of proportion here. 134 dB SPL is so very loud that you would not--could not--stay in a room where it was happening. You would soon be driven into such a high state of stress that you could well have a heart attack and die.

A pressure transducer (which these mikes evidently are) with a 134 dB maximum SPL specification could be placed 1" in front of the mouth of the loudest opera singer the world has ever known, and it wouldn't overload. You could put it in the bell of a trumpet or trombone, and at the loudest end of a professional player's ability it would occasionally clip--but if you backed it away a foot or more, the problem would be solved.

That's really what these extreme specifications are about: very close placement to exceptionally loud sound sources. Not 40 feet or 10 feet or even 2 feet away from a P.A. loudspeaker--because to produce 130+ dB SPL at those miking distances, the original sound would have to be so loud that everyone anywhere near the speakers would have permanent hearing loss within a fairly short time.

When I bought my first mbho rig from Nutter at sonic sense I asked about their 134db SPL. He jokingly said at 138 db it would make my ears bleed. 

[Cheesecadet]

Never overloaded my 4061s even when stack taping and extrmely close.

I would highly suggest you keep the microdot terminations and get a dual microdot to 1/8" cable made.  Darktrain made mine and it has been solid!