Strange clipping on Ribbon mic

Author
Post
Essentials Only Full Version
stuart3844
Max Output Level: -89 dBFS
  • Total Posts : 87
  • Joined: 2009/02/11 18:25:49
  • Status: offline
2012/10/30 10:22:45 (permalink)

Strange clipping on Ribbon mic

I a recording a guitar amp using an Golden Age active ribbon mic and am getting a strange asymmetric clipping on the waveforms. Levels are quite high and i am using the -10db pad on the mic and fairly low gain settings and pad on the A-D interface (Saffire pro 40).
 
Whilst recording a symmetric waveform is shown on the DAW (X1) but when the waveform plots properly the top side clips and the bottom side doesn't. I am also recording the same sound with another mic and this is normal so its not any peculiarity in the sound source. Recording vocal or acoustic sound at a lower level produces a normal result
 
Any ideas?????

Sonar X1 Studio, ToneBooster Voxengo and Klanghelm plugins
Windows7 64bit on AthlonII x4 631, 8GB
Studio - Focusrite Saffire Pro40, krk Rokit 5s
sE2200, 2xsE4s, AKG112, GA R1 Ribbon and loads of SM57s
Home -  Focusrite Saffire 6 USB, Alesis M1 Mk2s, DT990

Facebook - "York Road Studio"

#1

11 Replies Related Threads
    The Maillard Reaction
    Max Output Level: 0 dBFS
    • Total Posts : 31918
    • Joined: 2004/07/09 20:02:20
    • Status: offline
    Re:Strange clipping on Ribbon mic 2012/10/30 10:44:37 (permalink)
    Asymmetrical waveforms usually indicate that the signal is rich with odd ordered harmonic distortion.

    The little chips in active stuff are real good at making odd ordered distortion.

    If you like the sound... great!

    If you don't like the sound... use the lower levels.


    The figure 8 pickup pattern also hears sound much differently than other patterns, so consider that also when comparing to your other mics.


    best regards,
    mike



    #2
    Bristol_Jonesey
    Max Output Level: 0 dBFS
    • Total Posts : 16775
    • Joined: 2007/10/08 15:41:17
    • Location: Bristol, UK
    • Status: offline
    Re:Strange clipping on Ribbon mic 2012/10/30 12:37:45 (permalink)
    Ribbons usually need tons of gain to get a reasonable signal recorded.

    I'd check your entire chain and make sure it's gain-staged properly from start to finish


    CbB, Platinum, 64 bit throughout
    Custom built i7 3930, 32Gb RAM, 2 x 1Tb Internal HDD, 1 x 1TB system SSD (Win 7), 1 x 500Gb system SSD (Win 10), 2 x 1Tb External HDD's, Dual boot Win 7 & Win 10 64 Bit, Saffire Pro 26, ISA One, Adam P11A,
    #3
    Beagle
    Max Output Level: 0 dBFS
    • Total Posts : 50621
    • Joined: 2006/03/29 11:03:12
    • Location: Fort Worth, TX
    • Status: offline
    Re:Strange clipping on Ribbon mic 2012/10/30 15:09:27 (permalink)
    careful Colin - you're offering advice which could be considered "silly practice bordering on misinformation" according to someone....

    http://soundcloud.com/beaglesound/sets/featured-songs-1
    i7, 16G DDR3, Win10x64, MOTU Ultralite Hybrid MK3
    Yamaha MOXF6, Hammond XK3c, other stuff.
    #4
    The Maillard Reaction
    Max Output Level: 0 dBFS
    • Total Posts : 31918
    • Joined: 2004/07/09 20:02:20
    • Status: offline
    Re:Strange clipping on Ribbon mic 2012/10/30 15:42:23 (permalink)
    There was a mention that the other mic was working fine.

    And that the ribbon mic was getting hammered... hence the -10dBpads and the level settings. 

    It all makes too much sense.


    I'll bet moving the ribbon mic back away from the guitar amp another 11" will seem helpful.

    Sometimes I "face" it at a 30* to 45* degree angle so that wind blast coming off the speaker cone doesn't over load the ribbon by hitting it square, but more often than not I just move it back enough so that it doesn't get blasted. Probably about 15" maybe a little more, for starters.

    That is for a regular ribbon mic. 

    If it is an active ribbon mic you may need to move it back another 13" as the mic may simply have to much gain for close mic'ing on a loud amp.


    best regards,
    mike

     

    edit spelling
    post edited by mike_mccue - 2012/10/30 15:45:55


    #5
    bitflipper
    01100010 01101001 01110100 01100110 01101100 01101
    • Total Posts : 26036
    • Joined: 2006/09/17 11:23:23
    • Location: Everett, WA USA
    • Status: offline
    Re:Strange clipping on Ribbon mic 2012/10/30 17:00:53 (permalink)
    Or maybe the ribbon has gone slack and needs to be retensioned. 


    All else is in doubt, so this is the truth I cling to. 

    My Stuff
    #6
    stuart3844
    Max Output Level: -89 dBFS
    • Total Posts : 87
    • Joined: 2009/02/11 18:25:49
    • Status: offline
    Re:Strange clipping on Ribbon mic 2012/10/30 18:24:29 (permalink)
    Thanks for your replies. I had already pulled the mic back quite a bit, prob about 24in from the cab, but still the same effect. We haven't had the ribbon long and are just getting used to its peculiarities.

    We are recording the cab in a 6ft sqr booth to get separation. The booth is reasonably well conditioned, but i had wondered if the asymmetry was something to do with using a fig 8 pattern in a confined space. Was interested in your comment mike.

    I had read that ribbons were happy with high sound pressure levels, but may be thats not so much that case with active ones.  My main worry is that the mic is defective in some way.

    Yes the sound is acceptable and any distortion isn't obvious due to the slightly overdriven source material. Lower SPLs such as voice produces no clipping and a super smooth sound. So overall happy with the results we are getting.

    Sonar X1 Studio, ToneBooster Voxengo and Klanghelm plugins
    Windows7 64bit on AthlonII x4 631, 8GB
    Studio - Focusrite Saffire Pro40, krk Rokit 5s
    sE2200, 2xsE4s, AKG112, GA R1 Ribbon and loads of SM57s
    Home -  Focusrite Saffire 6 USB, Alesis M1 Mk2s, DT990

    Facebook - "York Road Studio"

    #7
    stuart3844
    Max Output Level: -89 dBFS
    • Total Posts : 87
    • Joined: 2009/02/11 18:25:49
    • Status: offline
    Re:Strange clipping on Ribbon mic 2012/10/30 18:27:21 (permalink)
    bitflipper


    Or maybe the ribbon has gone slack and needs to be retensioned. 


    Dave, just saw your post after i finished writing. The ribbon is new so wouldst expect it to need that. Maybe i should be contacting the manufacturer.

    Sonar X1 Studio, ToneBooster Voxengo and Klanghelm plugins
    Windows7 64bit on AthlonII x4 631, 8GB
    Studio - Focusrite Saffire Pro40, krk Rokit 5s
    sE2200, 2xsE4s, AKG112, GA R1 Ribbon and loads of SM57s
    Home -  Focusrite Saffire 6 USB, Alesis M1 Mk2s, DT990

    Facebook - "York Road Studio"

    #8
    stuart3844
    Max Output Level: -89 dBFS
    • Total Posts : 87
    • Joined: 2009/02/11 18:25:49
    • Status: offline
    Re:Strange clipping on Ribbon mic 2012/10/30 18:42:07 (permalink)
    Just found this thread with exactly the same thing on the same type of mic

    http://www.gearslutz.com/board/so-much-gear-so-little-time/470550-strange-waveform.html

    Sonar X1 Studio, ToneBooster Voxengo and Klanghelm plugins
    Windows7 64bit on AthlonII x4 631, 8GB
    Studio - Focusrite Saffire Pro40, krk Rokit 5s
    sE2200, 2xsE4s, AKG112, GA R1 Ribbon and loads of SM57s
    Home -  Focusrite Saffire 6 USB, Alesis M1 Mk2s, DT990

    Facebook - "York Road Studio"

    #9
    quantumeffect
    Max Output Level: -47.5 dBFS
    • Total Posts : 2771
    • Joined: 2007/07/22 21:29:42
    • Location: Minnesota
    • Status: offline
    Re:Strange clipping on Ribbon mic 2012/10/30 19:41:46 (permalink)
    Asymmetric waveforms are very common when recording drums and some mic’s exacerbate the effect more than others (at least in my experience).  For example, if I run a side-by-side comparison of an EV RE20 and an AKG D112 on my base drum, the lopsided or asymmetric effect is more prevalent in the waveform generated by the EV RE20.

    From a practical stand point, the bass drum sounds as it should, but the lopsided waveform presents processing issues.  If I apply a compressor to the track, it appears as though the threshold is governed by the peak values on one side of the waveform yielding a less than optimal result.

    I too have read over the years that the effect is the result of:

    even-ordered harmonics
    odd-ordered harmonics
    out of phase harmonics
    air pushing on the diaphragm

    … but I have yet to find a published study systematically evaluating the effect (just people quoting other people from gearslutz).

    The guy in this video that was posted about a year ago does a really good job of systematically eliminating electronic artifacts and ascribes the origin of the effect to a lopsided sound source (it is worth watching and the text is transcribed for you).

    http://www.youtube.com/watch?v=-a8-ULhmz_4


    post edited by quantumeffect - 2012/10/30 21:21:16

    Dave

    8.5 PE 64, i7 Studio Cat, Delta 1010, GMS and Ludwig Drums, Paiste Cymbals

    "Everyone knows rock n' roll attained perfection in 1974. It's a scientific fact." H. Simpson

    "His chops are too righteous."  Plankton during Sponge Bob's guitar solo 
    #10
    The Maillard Reaction
    Max Output Level: 0 dBFS
    • Total Posts : 31918
    • Joined: 2004/07/09 20:02:20
    • Status: offline
    Re:Strange clipping on Ribbon mic 2012/10/30 19:55:37 (permalink)
    Hi Dave,

     A great way to observe this is to use an additive synthesizer and dial up some tones by purposefully adding even or odd ordered harmonics and then recording some stabs. Record them clean so that the signal chain doesn't introduce any distortion.


     In the OPs case, now that he has mentioned the 6' guitar booth... it could also be comb filtering.

     I think it's still most likely that it's just too loud in there for that mic... it's hard to say if it's before or in the onboard preamp.  If it's before it could be saturation on the transformer. It could also be the ribbon getting over worked.

     It's reassuring to think that it still sounds fine with lower volume sources like singers and acoustic guitar.


     At this point I'd suggest pulling the amp out of the small room and trying the mic out in a larger space.


     BTW, what was the other mic that seems to work ok? The sm57? Or the SE2200?


     best regards,
    mike


     


    post edited by mike_mccue - 2012/10/30 19:56:52


    #11
    bitflipper
    01100010 01101001 01110100 01100110 01101100 01101
    • Total Posts : 26036
    • Joined: 2006/09/17 11:23:23
    • Location: Everett, WA USA
    • Status: offline
    Re:Strange clipping on Ribbon mic 2012/10/30 21:14:17 (permalink)
    The ribbon is new so wouldst expect it to need that. Maybe i should be contacting the manufacturer.

    I didn't expect the rear hatch on my new car to leak, either, but it did.


    All of these inexpensive ribbons are made on the cheap in Shanghai and are famous for their high rate of manufacturing defects, ribbon tension being #1 on the list. I've read many accounts of people having to re-tension ribbons on brand-new Chinese ribbon microphones (as well as tighten screws and reassemble basket components that were left rattling around inside after manufacture).  


    Michael Joly, who's quite the expert on such things, says that 30 to 50 percent of new Chinese ribbons are improperly tensioned. And guess what? One symptom of an improperly tensioned ribbon can be asymmetrical waveforms.


    Good luck contacting the manufacturer. Hope you speak Chinese! :)


    All else is in doubt, so this is the truth I cling to. 

    My Stuff
    #12
    Jump to:
    © 2024 APG vNext Commercial Version 5.1