Topic: SPL question for someone in the know...

[Cheesecadet]

Hey all...just curious.  When comparing 2 different mics, and the maximum input SPL is 125dB vs. 131dB...which mic is better???  I always get confused when dealing with dBs and I thought the 131db mics would be better but I am not sure.

Can anyone answer this with some support for me???

Thanks

Ryan in WA

[Genghis Cougar Mellen Khan]

Hey all...just curious.  When comparing 2 different mics, and the maximum input SPL is 125dB vs. 131dB...which mic is better???  I always get confused when dealing with dBs and I thought the 131db mics would be better but I am not sure.

Can anyone answer this with some support for me???

Thanks

Ryan in WA

The mics that can handle 131db spl would just take a bit more sound pressure before they would distort.  Mics with a lower SPL might sound a lot better than the mic that can handle higher SPL's, it really depends on the mic and what you're looking for.  The SPL spec is when the mic is powered to the manufatureres spec, so if you're using an aftermarket battery box that spec might mean anything.  Look into the 3-wire battery boxes if you're considering an aftermarket power supply (IE: sound pros).

[balou2]

Mr. Neroy!  Welcome!!!

Mike Tausig

[Cheesecadet]

Hey Mike...it's been a while.  I hope all is well with you.  I've been lurking around this site for some time now just asking questions here and there.  I'm planning on picking up a new stealth rig (fairly inexpensive) and trying to figure out some of the techy stuff i don't know..

Anyway, good to hear from you!  Later...

Ryan

[Church-Audio]

Hi that’s a very good question First off in order to know who spec is better we have to know at what frequency or group of frequencies the distortion test was conducted.

Allot of manufactures use 1k. Some use at least 5 or 6 different frequencies and average them out. The latter is the best method because a condenser mic is actually more prone to distortion at low frequencies then high ones. In most cases so a measurement at 1k does not tell you much.

So I guess what I am trying to say is you almost have to contact the technical department of these companies to find out how they are measuring the distortion in the microphones they make. I use a computer program + a sound source that will put out 1k at 114 db with a distortion of less then 0.02%.

Other companies do things differently. Some use pure math to figure out distortion.

I am sure there are many opinions on this subject. At the end of the day talk to the other users of this board. I doubt that there is any mic out there that a user here has not used, and knows about its distortion or lack of distortion.


Chris Church

Hey all...just curious.  When comparing 2 different mics, and the maximum input SPL is 125dB vs. 131dB...which mic is better???  I always get confused when dealing with dBs and I thought the 131db mics would be better but I am not sure.

Can anyone answer this with some support for me???

Thanks

Ryan in WA

[balou2]

Chris is right...if you have questions about a specific mic, someone here has likely used it.

The SHURE site has a cool educational description on SPL

http://www.shure.com/support/technotes/app-sensitive.html

[Nick's Picks]

the best mic I owned only had a limit of 119db

[12345]

the best way to tell which setup is better is to compare the two... Which SOUNDS BETTER?  Price and specs don't mean a thing, what does it sound like? 

[guysonic]

SPL handling ability seems important when recording certain types of venues with strong 'over-th-top' bass content.  Bass is by far the largest (sound energy) part of a live sound pop/rock type venue.   My experiences indicate that 125 dB SPL handling is mostly OK for 80-90% pop/rock recording unless maybe right up against the stacks (likely should be wearing hearing protection).   

130+ SPL handling is needed for extreme loudness bass venues, and most needed for recording very near the speakers. 

Maybe good to remember the mic must be rated for the PEAK energy content of the bass, not the average signal, so having this seemingly high loudness handling for those 'gut-thumping-bass' sounds does improve the ability of recording clean sounding low frequency content.

For recording extreme bass or espeicially if positioned very near the speakers, a 1 pole (6 dB/octave high pass) bass filter (of at least 85 cycles to sometimes as much as 250 cycles setting) is most useful as it will help limit the excessive bass signal going into the first mic amp stage (less likely to produce clipping distortion); allowing the recording level of the mid-to-high frequencies to be increased.  This usually gives a cleaner, more balanced sounding 'raw' recording that plays better with no or needing less bass reduction (for speaker playback or in post editing).

[guysonic]

130+ SPL handling is needed for extreme loudness bass venues, and most needed for recording very near the speakers. 

To expand a bit on this topic I must relate sobering experience 4-5 years ago from DSM-6S/EL (ok with 134+ dB SPL) mic customer recording pop/rock concert in Japan using just 85 cycle bass filter.  Complaint was 'muddy or distorted sounding bass' at good distance from speakers using D8 deck mic input set at 'LOW' mic input sensitivity.  Customer offered to send DAT dub typical of problems experienced at concerts in Japan.

Doing a simple spectrum analysis of the rock concert DAT recording showed the 20-100 cycle low bass sound (with effect of 85 cycle filter removed) was nearly 40 dB ABOVE the mid-high frequencies!  I then realized those Japan pop/rock concerts (at least at that time) were typical for 'FLOATING' THE AUDIENCE in a massive 'sea of bass energy' that must be very exciting to experience! 

However, making a recording of this meant the mid-high frequencies were later heard as totally 'drowned in a sea of bass,' and worse, the deck was being overloaded (first stage mic preamp clip distortion) by the mic's (undistorted) higher signal output from the 'way-way-over-the-top' bass sound energy (SPL).

This was the first bass distortion complaint (with DSM-6S/EL model) that resulted in a new most agressive bass filter product with three high pass filter choices of 85/170/250 cycles.

In Japan, for these type concerts in Japan/Germany, this was mostly used in the 170/250 cycle settings to solve both deck overload, and allow a clean unclipped recording, and with more balanced sounding bass more compatible for enjoying on home type speaker systems.

[Church-Audio]

As a concert engineer I have to agree with what you’re saying. The problem is exacerbated by the Fletcher Munson curve if I need to get it to be 115db at 100' I have to reduce highs and pump lows up so I do not kill the people in the first row and so that my mix is not "top end heavy"

I also know that the sound system couples at a close distance so the inverse square law is multiplied many times because of this coupling of speaker cabinets. For bass speakers a well designed sound system will yield a 3db to 2.5db increase in sound pressure for every bass cabinet I add to the system. That is allot of free power just because of coupling.

So 115db at 100' it can be 130+ close up not maybe broad band (full spectrum) but for sure the low end can be that level. I also think for some reason some people do not realize that bass can damage your hearing just as well as highs can. I hate to see people right up against a sound system at a large venue where I know I have to push levels.That's is one reason why we fly our sound systems but even with a system that is hung in the air the bass cabinets in most cases are still at chest height on the ground.

 

130+ SPL handling is needed for extreme loudness bass venues, and most needed for recording very near the speakers. 

To expand a bit on this topic I must relate sobering experience 4-5 years ago from DSM-6S/EL (ok with 134+ dB SPL) mic customer recording pop/rock concert in Japan using just 85 cycle bass filter.  Complaint was 'muddy or distorted sounding bass' at good distance from speakers using D8 deck mic input set at 'LOW' mic input sensitivity.  Customer offered to send DAT dub typical of problems experienced at concerts in Japan.

Doing a simple spectrum analysis of the rock concert DAT recording showed the 20-100 cycle low bass sound (with effect of 85 cycle filter removed) was nearly 40 dB ABOVE the mid-high frequencies!  I then realized those Japan pop/rock concerts (at least at that time) were typical for 'FLOATING' THE AUDIENCE in a massive 'sea of bass energy' that must be very exciting to experience! 

However, making a recording of this meant the mid-high frequencies were later heard as totally 'drowned in a sea of bass,' and worse, the deck was being overloaded (first stage mic preamp clip distortion) by the mic's (undistorted) higher signal output from the 'way-way-over-the-top' bass sound energy (SPL).

This was the first bass distortion complaint (with DSM-6S/EL model) that resulted in a new most agressive bass filter product with three high pass filter choices of 85/170/250 cycles.

In Japan, for these type concerts in Japan/Germany, this was mostly used in the 170/250 cycle settings to solve both deck overload, and allow a clean unclipped recording, and with more balanced sounding bass more compatible for enjoying on home type speaker systems.

[mmmatt]

the best mic I owned only had a limit of 119db

was that a ribbon or something Nick?

Matt

[Genghis Cougar Mellen Khan]

130+ SPL handling is needed for extreme loudness bass venues, and most needed for recording very near the speakers. 

To expand a bit on this topic I must relate sobering experience 4-5 years ago from DSM-6S/EL (ok with 134+ dB SPL) mic customer recording pop/rock concert in Japan using just 85 cycle bass filter.  Complaint was 'muddy or distorted sounding bass' at good distance from speakers using D8 deck mic input set at 'LOW' mic input sensitivity.  Customer offered to send DAT dub typical of problems experienced at concerts in Japan.

Doing a simple spectrum analysis of the rock concert DAT recording showed the 20-100 cycle low bass sound (with effect of 85 cycle filter removed) was nearly 40 dB ABOVE the mid-high frequencies!  I then realized those Japan pop/rock concerts (at least at that time) were typical for 'FLOATING' THE AUDIENCE in a massive 'sea of bass energy' that must be very exciting to experience! 

However, making a recording of this meant the mid-high frequencies were later heard as totally 'drowned in a sea of bass,' and worse, the deck was being overloaded (first stage mic preamp clip distortion) by the mic's (undistorted) higher signal output from the 'way-way-over-the-top' bass sound energy (SPL).

This was the first bass distortion complaint (with DSM-6S/EL model) that resulted in a new most agressive bass filter product with three high pass filter choices of 85/170/250 cycles.

In Japan, for these type concerts in Japan/Germany, this was mostly used in the 170/250 cycle settings to solve both deck overload, and allow a clean unclipped recording, and with more balanced sounding bass more compatible for enjoying on home type speaker systems.

In my experiences with the DSM-6S/EL mics was that they OR the bass filter were the inherent weakness when it came to bass distortion issues.  Devices with much higher input levels have not distorted the mic input, it's not the deck that is the problem.

[guysonic]

130+ SPL handling is needed for extreme loudness bass venues, and most needed for recording very near the speakers. 

To expand a bit on this topic I must relate sobering experience 4-5 years ago from DSM-6S/EL (ok with 134+ dB SPL) mic customer recording pop/rock concert in Japan using just 85 cycle bass filter.  Complaint was 'muddy or distorted sounding bass' at good distance from speakers using D8 deck mic input set at 'LOW' mic input sensitivity.  Customer offered to send DAT dub typical of problems experienced at concerts in Japan.

Doing a simple spectrum analysis of the rock concert DAT recording showed the 20-100 cycle low bass sound (with effect of 85 cycle filter removed) was nearly 40 dB ABOVE the mid-high frequencies!  I then realized those Japan pop/rock concerts (at least at that time) were typical for 'FLOATING' THE AUDIENCE in a massive 'sea of bass energy' that must be very exciting to experience! 

However, making a recording of this meant the mid-high frequencies were later heard as totally 'drowned in a sea of bass,' and worse, the deck was being overloaded (first stage mic preamp clip distortion) by the mic's (undistorted) higher signal output from the 'way-way-over-the-top' bass sound energy (SPL).

This was the first bass distortion complaint (with DSM-6S/EL model) that resulted in a new most agressive bass filter product with three high pass filter choices of 85/170/250 cycles.

In Japan, for these type concerts in Japan/Germany, this was mostly used in the 170/250 cycle settings to solve both deck overload, and allow a clean unclipped recording, and with more balanced sounding bass more compatible for enjoying on home type speaker systems.

In my experiences using the DSM-6S/EL model mics was that they OR the bass filter were the inherent weakness when it came to bass distortion issues.  Devices with much higher input levels have not distorted the mic input, it's not the deck that is the problem.

In my experience with communicative users reporting bass distortion while recording extremely high (>128 dB) SPL with DSM-6S/EL models working into the mic input set at -20 dB or 'LOW' sensitivity, is this is (mostly) solved by using the most agressive PA-6LC3B model powering adapter set at 170 or 250 cycles.   Effective bass filtering at the mic output eliminates deck's first stage (mic input) overloads; this works to avoid the clipping that happens BEFORE the REC level adjustment 2'd stage to acceptable non-distorting deck input levels.   

While DSM-6S/EL mics are untypical with having VERY low level output suitable ONLY for MIC INPUT, most ALL other types of mics (except some dynamic types) have much greater signal (voltage) output that mostly require using ONLY the LINE input, and/or aggessive output attenuation (in-series network) to avoid deck generated clipping distortion. 

[Genghis Cougar Mellen Khan]

In my experience with communicative users reporting bass distortion while recording extremely high (>128 dB) SPL with DSM-6S/EL models working into the mic input set at -20 dB or 'LOW' sensitivity, is this is (mostly) solved by using the most agressive PA-6LC3B model powering adapter set at 170 or 250 cycles.   Effective bass filtering at the mic output eliminates deck's first stage (mic input) overloads; this works to avoid the clipping that happens BEFORE the REC level adjustment 2'd stage to acceptable non-distorting deck input levels.   

While DSM-6S/EL mics are untypical with having VERY low level output suitable ONLY for MIC INPUT, most ALL other types of mics (except some dynamic types) have much greater signal (voltage) output that mostly require using ONLY the LINE input, and/or aggessive output attenuation (in-series network) to avoid deck generated clipping distortion. 

170 Cycles mic in with the -20 att engaged, this is into an Oade mod'ed mic input.  The mic in can easily handle DPA406X series mic output, CSB output which are well above the output level of the DSM/PA-6LC3B combo, the level knob at no lower than 7.  DiStOrTiOn.  The wavform shows signs of capsule failure, not brickwalling, it's probably attributed to the lower bias voltage use to power the mics (1.5v).  While they sound much better than a simple rev-polarity modified WM capsule running on 9v they just can't hang with higher SPL's, esp. lower frequencies.