Plug an SM58 in a guitar amp?

Discussion in 'Recording/Live Sound' started by MartinPiana, Feb 27, 2012.

  1. MartinPiana

    MartinPiana Supporting Member

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    Is this going to work OK? Somebody was saying something to me about high v. low impedence.... About an SM57, any difference?

    Obviously, I'm a neophyte on such matters....

    Thanks.
     
  2. Peteyvee

    Peteyvee Premium Platinum Member

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    We used to do that in the old days. It will work, but sound terrible. Guitar amps don't do well with the human voice...
     
  3. stevel

    stevel Member

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    Right. Most mics work on Low Impedance and use an XLR connector.

    Guitar amps do not.

    So you have a couple of options:

    Buy a high impedance mic that uses a 1/4 cable. Typically these are of lesser quality.

    Buy a impedance selector which basically "converts" mic level to line level.

    XLR, low impedance, balanced (mic) cables have 3 wires in them. 1/4", high impedance, unbalanced (guitar) cables have only 2 wires in them.

    For this reason, you can't just buy an XLR to 1/4" adapter that isn't a TRS (tip/ring/sleeve) connector on the 1/4" side (without the wiring having had something sneaky done to it).

    You also in general should not plug TRS connectors into standard TS (tip/sleeve - like regular guitar cables) jacks - it can cause damage in some components (so don't plug headphones into line out, effects out, or other non-headphone out jacks).

    Your best option is to run a mic into something designed for it instead of a guitar amp (unless of course you can find a good high imp mic specifically designed for that purpose). As Peteyvee notes, the frequency response of a guitar amp is also not designed for vocals and unless you're just using it for simple announcements, it's not good for much else.

    HTH,
    Steve
     
  4. JohnSS

    JohnSS Member

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    It depends on your application. If you're using for rehearsal or to process vocals through stompboxes for an effect, then I don't see why not. You can get an adapter XLR to 1/4". Don't expect a pristine recording quality sound.
     
  5. phillygtr

    phillygtr Member

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  6. fisticuffs

    fisticuffs Member

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    You need more than an adapter. As explained earlier you have electrical problems to do with. You need a transformer (looks like a big fat adapter) that will match the impedance the amp is expecting to see. Only then will it still sound awful. Not worth your effort. buy a keyboard or acoustic amp meant to handle a mic.
     
  7. MartinPiana

    MartinPiana Supporting Member

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    So my local independent music store has a low to hi, XLR to 1/4" adaptor. the schematic shows it goes from 3 wires to 2. While the guitar amp is not voiced well for vocals, this adaptor should make the mic work as well as it's going to with this amp, right?

    This is what I'm talkin bout: http://www.google.com/products/cata...=X&ei=6_ZLT6LaI8jniALamK3bDQ&ved=0CIMBEPMCMAI
     
  8. rickenbackerkid

    rickenbackerkid Member

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    Yep, it will work but won't sound good for voice.
     
  9. stevel

    stevel Member

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    1. Thank you for supporting your local music store :aok.

    2. Yep - it's got to get rid of one of the wires some way. This basically means it "cheats" and to say it kind of simply, "removes some of the signal" too.

    3. Yes it will work as good as it will work. However, if you can find one with a transformer/impedance selector (as mentioned above), THAT will work as well as it's going to work. See: http://www.google.com/products/cata...sa=X&ei=0BtMT_Qp6cfQAfXPzJAO&ved=0CIMBEPMCMAA (not necessarily this particular model).

    Steve
     
  10. Rockerduck

    Rockerduck Member

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    I ain't terrible. I plug a Sm58 into the first channel of my Deluxe Reverb and play in the second channel. I use it for harmonica. Sometimes I sing alittle while playing the harp too. Not for connoisseurs, but it'll do.
     
  11. Nelson89

    Nelson89 Member

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    Whats the purpose of all of this? I have the boxes to do all this, but i'll only ever do it if i want that particular effect of essentially a saturated vocal sound that sounds like it's been through a filter, cool effect yeh, but not something i'd use all that often. Basically the right way to do it all would be to run it into a mic pre, then a reamp box, then into the amp.

    If the purpose is for practicing or whatever, i think in the long run it'll be cheaper and less hassle to get an acoustic amp or keyboard amp or mini PA to use instead if all you're wanting to do is hear the vocals. If all you want it for is the effect, then basically what i said above.
     
  12. jay42

    jay42 Member

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    ...if you're really going to do it, there isn't really a flat eq available, however, on a Fender you would start with Mid maxed, bass 1-2, treble 1-2.
     
  13. speakerjones

    speakerjones Member

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    I wouldn't start with anything maxed cuz it's probably going to feedback like a bitch.

    I actually wouldn't do it all unless you're 15, flat broke and starting your first punk rock band. In which case, it's OK.
     
  14. lspaulsp

    lspaulsp Gold Supporting Member

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    Check with Radio Shack. They used to make a Lo to Hi Impedance adapter which was 1/4". It actuially went from Lo to Hi.
     
  15. SideBMusic

    SideBMusic Supporting Member

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    Well, it sounds like something The Beatles would do to get a new effect.
     
  16. Peteyvee

    Peteyvee Premium Platinum Member

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    Harp doesn't have the same frequency response as the human voice and I'm sure it sounds OK for your purposes. You would sound a lot better playing harp through a different amp and singing through a PA, but I see where you're coming from and if it works for you, that's fine.

    Probably? :spit

    :spit:spit:aok
     
  17. phazersonstun

    phazersonstun Member

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    As far as not starting with anything maxed.........

    With most Fender tone circuits, the mid control is cut only.
    This means the mid control maxed is FLAT. Not boosted in any way.
     
  18. Peteyvee

    Peteyvee Premium Platinum Member

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    A Deluxe Reverb doesn't have a mid control. Isn't that what the OP has or am I getting confused? In any case, if I was going to revert to my misspent youth and plug a mic into a guitar amp, no matter what it is, I'm going to start with everything all the way down and then gradually turn it up until I know how the mic is going to react with the amp. IMO: That's just common sense.
     

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