Balanced or Ubalanced?

[sbmackie]

Hello,
I'm plugging a Shure SM57 into an amps that ha that has only two inputs, one of which is a 1/4 inch vs XLR. Do I need a "balanced" cord? The amp is not true stereo if that matters. But, the amp MAY be used as a PA component (it has a DI line out). Does that matter?

Thanks
Scott

[jonfields45]

The XLR cable from the mic to the amp is a balanced cable. All balanced means is there is a third wire for ground (and shield) separate from the + and - for the signal.

[sbmackie]

Jon,
Thanks for your reply. My very limited understanding is the mic is low impedance and the amp is high impedance which requires the use of a specific kind (balanced or unbalanced) The question is: which one?
Scott

[lschwart]

Originally Posted by sbmackie

Jon,
Thanks for your reply. My very limited understanding is the mic is low impedance and the amp is high impedance which requires the use of a specific kind (balanced or unbalanced) The question is: which one?
Scott

If the amp has an XLR input, then it is expecting a mic level, low impedance, balanced signal at that input. Use a regular XLR mic cable from the mic to the XLR input. Simple as that.

By the way, what brand and model is the amp?

Louis

[sbmackie]

Isch,
Maybe I'm not being clear. There is one XLR input, and one 1/4 inch input on the amp. I have no pickup on my guitar. I am using one mic for vocals in the XLR input, and I will mic the guitar externally and plug into the 1/4 inch jack.
The amp I am considering is a Marshall AS 50R or AS 50 D. I bought an amp that has inputs that will accept either XLR, or 1/4 inch plugs, and may keep that one, so the question still stands.
Scott

[lschwart]

Originally Posted by sbmackie

Isch,
Maybe I'm not being clear. There is one XLR input, and one 1/4 inch input on the amp. I have no pickup on my guitar. I am using one mic for vocals in the XLR input, and I will mic the guitar externally and plug into the 1/4 inch jack.
The amp I am considering is a Marshall AS 50R or AS 50 D. I bought an amp that has inputs that will accept either XLR, or 1/4 inch plugs, and may keep that one, so the question still stands.
Scott

OK. Ideally you would want two balanced, low impedance XLR inputs for your mics, but in some cases (if there's enough gain and you're cable is short) you can put a mic into a higher impedance 1/4" input with a simple XLR female to 1/4" cable. You'll just have to try. An amp with two XLR / 1/4" combo inputs (which can take either) like a Fishman Loudbox Artist might be a better fit for you, though.

Louis

[pieterh]

At best you will get a rather thin sound from the mic going into the non-xlr input, at worst the level will be very low and noisy (as the input is not really designed for low level balanced signals). You might be better off investing in a floor pedal of some sort that will take the mic signal, buffer it (boost it a bit) and then send it onwards via a regular tele output.

There are of course players who use mics directly into amps - blues harmonica players for example - so it may be fine. Bear in mind that those players rarely get or are even after a clean sound.

Which amp are you using?

[fotofantom]

...or, get yourself a small mixer with at least two XLR inputs, plug in your two mics, and run an XLR cable out to the amp.

[varmonter]

Originally Posted by fotofantom

...or, get yourself a small mixer with at least two XLR inputs, plug in your two mics, and run an XLR cable out to the amp.

this.... You really need two xlr inputs for what
you want to do. Do you know if your 1/4 inch
input on your amp is balanced ?? trs??
if not plugging your mic in may create a buzz..

[jonfields45]

Originally Posted by sbmackie

Isch,
Maybe I'm not being clear. There is one XLR input, and one 1/4 inch input on the amp. I have no pickup on my guitar. I am using one mic for vocals in the XLR input, and I will mic the guitar externally and plug into the 1/4 inch jack.
The amp I am considering is a Marshall AS 50R or AS 50 D. I bought an amp that has inputs that will accept either XLR, or 1/4 inch plugs, and may keep that one, so the question still stands.
Scott

If you do not mind sharing common tone and volume controls (and turning the volume up 6db higher, but that is not going to be a problem), an XLR Y-cable (standard stock item at Guitar Center) will combine two dynamic mics into a single XLR input. Another solution is a matching transformer, also Guitar Center standard stock, which will adapt the second mic's XLR to the 1/4" input (it will step up the voltage and you won't notice any gain or noise problems). Some options:

https://www.guitarcenter.com/Livewir...ale-Y-Cable.gc

https://www.guitarcenter.com/Audix/T...Transformer.gc

Since you've not purchased the amp yet, I agree it makes more sense to buy an amp with two channels compatible with an XLR cable.

[sbmackie]

Jon,
If I understand correctly, the transformer doohickey will make the microphone xlr compatible with the 1/4 inch in terms of impedence, signal hotness,etc. Maybe not perfect, but close.
Yes?
Scott

[sdelsolray]

Nevermind.

[jonfields45]

Originally Posted by sbmackie

Jon,
If I understand correctly, the transformer doohickey will make the microphone xlr compatible with the 1/4 inch in terms of impedence, signal hotness,etc. Maybe not perfect, but close.
Yes?
Scott

Yes. It will work just fine.

[Br1ck]

I would not buy an amp that could not handle two XLR cables, or one that did not have a Hi Z switch. At some point, someone is going to want to plug a piezo equipped guitar in.

It sounds to me like you would be better off with a powered speaker and a small mixer. Later you could add a second powered speaker and have a mini PA, or send a signal from your mixer to a house PA and use the powered speaker as a monitor. I think you will get a better vocal sound this way, and with no pickup in your guitar, why buy an acoustic amp designed for a pickup?

I'll put a plug in for the late lamented Carvin AG300, which has two XLR inputs, but they are no longer made, so you'd need to find one used.

[jonfields45]

One last piece of unsolicited advice... While using a mic for your guitar is a good option, if you gig that way with any regularity you are going to want a pickup in your guitar.