Topic: Heavy bass distortions.

[JD]

Last night I recorded Railroad Earth at the Sherman Theater in Stroudsburg, PA.  The overall sound level in the room was of normal levels, but way heavy in bass. It literally shook the place all night, I could see it vibrating my drink and at times it almost made me feel ill.

I recorded about the middle of the room with the following; DPA4060> MMA600> r-09.  Almost every bass note distorts on the recording, dumping the bass in post did not help and you can see the distortions in the sound waves in soundforge. The levels peak at -6db.  I have never had this problem in the past,  and I  am now  wondering what happened and what I could have done different. In the few areas on the recording that the bass player wasn't thumpin away, the recording sounds fantastic.

What do you think distorted, the mics? the pre? the recorder?
Would the bass cut on the pre helped?


On another note, this was my first time around with both the band and the venue. The venue gets two thumbs up, laid back,  mellow security, way taper friendly, and good beer.

The band, not sure what to say, its the first time in many years that I have been blown away llike that. I had a great time and the whole scene last night had a great vibe going on (besides the bass vibes ).

I saw several stands up about the place. If anyone here ran there last night, I would love a copy.

[JD]

The mma6000 batter had maybe 6 to 8 hours before last night(LED is still green).

Line in.   
Level on r-09   = 5
Level on MMA6000  = +15db
agc =  off
mic gain =  low

[JD]

Hooked up the mics and ran the mma6k for about 15 min, led stayed green.

What exactly do you mean by overloading the mma6k?  Was the mic signal too hot for it?

I thought about flipping the HPF on at the beginning of the show but was reluctant to do so being unsure of the results. Kind of wish i would of for at least one song so I could see the difference it makes.

[BayTaynt3d]

Since it seems you were bricking well under 0 db (not clipping), then the evidence seems to point to either the mics or the preamp bricking, but not the recorder clipping. The mics could brick by being under-powered or simply from too much SPL than they could handle. Running rolloff might have helped a lot, because there's a lot of energy down in those lows, and if you had a pad on those mics that would have been interesting to see. If it was the preamp and not the mics, it might be possible to put a pad inline between the mics and the preamp like this: mics > pad > preamp. But not sure about that, anyone?

[sml42]

What do you think distorted, the mics? the pre? the recorder?

If the bass was loud enough to make your drink shake, then I'd say your mics self-distorted.

I've run dpa4060>mps6030>jb3 on many occasion and had exactly this problem, with just a handful of bass-heavy shows. The mps6030 has no gain - it's a straight battery box - and I cranked the gain on the jb3 right down, after transfer audacity showed peaks at around -6dB and it still sounded badly distorted to the ears. I looked at it every which way and came to the conclusion it couldnt't be anything other than my mics self-distorting.

My solution was to buy a pair of dpa4061s and run those if I knew in advance it was going to be bass-heavy

[JD]

If the bass was loud enough to make your drink shake, then I'd say your mics self-distorted.

That is what I am thinking happened. Have you ever had this problem with your 4061's?

[Patrick]

You wouldn't think that RRE would be the type of band that would produce "sickening" bass frequencies.  Interesting.

[sml42]

If the bass was loud enough to make your drink shake, then I'd say your mics self-distorted.

That is what I am thinking happened. Have you ever had this problem with your 4061's?

Not yet. I recorded mogwai from stagelip with 4061s - they're notorious for having thunderous bass, and the recording came out just fine. By way of comparison I'd previously recorded mogwai FOB with the 4060s, and got distortion. This isn't very scientific - we're talking different venues spaced months apart - but my gut feeling is that the 4061s will cope with the highest SPLs I'd ever expect to encounter.

That's not to say the 4061s are the perfect one-size-fits-all mic though. I ran dpa4061>mps6030>mt2496 recently at a (relatvely quiet) acoustic show. The recording came out merely okay, the noise floor was too high for my liking. The 4060s would have been a better choice in my opinion. It's unclear how much noise is coming from the mics or MT preamp. It would be interesting to run the 4061s through a super-clean preamp (like the mma6000) to see how good/bad the MT preamp really is, but that's not really an option for me at the moment.

[JD]

You wouldn't think that RRE would be the type of band that would produce "sickening" bass frequencies.  Interesting.

Yeah, I would have thought the same thing. I have never come across such strong bass in the hundreds of shows I have seen.
The bass was also hot for the opening band, Hackensaw Boys, as well as the background music played between sets. Guess the sound guy just felt like shakin' the Sherman Theater that night.

I ran dpa4061>mps6030>mt2496 recently at a (relatively quiet) acoustic show. The recording came out merely okay, the noise floor was too high for my liking. The 4060s would have been a better choice in my opinion.

I tape mostly acoustic shows, that is why I choose the 4060's. I'll have to keep my eyes open for a set of 4061's for the occasional loud music I tape.