Fitting Microphones Inside A Concertina

[Alan Day]

I have used various mike systems.Internal mikes are OK if you do not use the air button and when you do it sounds as if you are having an asthma attack.I quickly took the mikes out.

Small mikes fitted to the concertina,to the hand amplify those notes near to the mike and reduced sound from those notes not in line with the mike

Cheap mikes also sound very tinny and requires total switch off of the treble and high use of the base.Not a nice sound at all

.My final solution was two good quality mike's placed about 18inches from each end to allow for bellows movement,fixed on stands and I have never found a better system of amplifying a concertina.

Al

[Wolf Molkentin]

I have used various mike systems.Internal mikes are OK if you do not use the air button and when you do it sounds as if you are having an asthma attack.I quickly took the mikes out.

Small mikes fitted to the concertina,to the hand amplify those notes near to the mike and reduced sound from those notes not in line with the mike

Cheap mikes also sound very tinny and requires total switch off of the treble and high use of the base.Not a nice sound at all

.My final solution was two good quality mike's placed about 18inches from each end to allow for bellows movement,fixed on stands and I have never found a better system of amplifying a concertina.

Al

 

Sounds reasonable.

 

Anyway, this morning it came to my mind that such a setting might be improved by the use of "plexi" walls just as some drumers do. One at the left and one at the right, which should collect the total of the instrument's sound and produce some nice reverb (just like sitting and playing in the bath room or so...).

 

But scarcely any player will want to expend effort on stage thus far, I'd guess...

[Stefan]

Using only one mic in the middle of the bellows seems to be a very good idea to me. The evenness and the volume would be ideal, also avoiding frettnoises.

 

Another technical term is, if a sound is "out of phase" (here is technical background: http://en.wikipedia.org/wiki/Out_of_phase#Phase_difference). Phasing can happen (it doesn´t have to) if two soundsources (e.g. mics) pic up the same sound but in slightly different locations (e.g. two different ends of a concertina). The overlay of the two signals can have the effect of cancelling out the sound. That means that the sound gets thinner. Probably some tones would be louder and round others would be soft and thin. If that happens with inside mics of a concertina, there is nothing you could do about it. With only one mic that could not happen.

 

I was also wondering how a concertina sounds INSIDE the bellows. Maybe it´s great, but there is the possibility of a strange sound just like in a tube.

 

So Dirge, if you are not afraid of the mechanical issues, there is pioneer work to be done. Maybe the cheap mics are just fine.

 

In any case (one or two mics) I would recommend a small mixer at the end of the mics. It has a few advantages: A decent mixer has phantom power, better mic preamps (to bring the mic level up to a usable output), you can mix a mono or stereo signal (with the left-right panning knobs, same as "balance" on stereo system), you can adjust your level and you have the possibility of making a "monitor-mix" for yourself.

 

Another advantage of two mics and a mixer is the possibility of adjusting the level of the right and left side independently (like Geoff pointed out).

[Stefan]

The more I think about it, the more I get the idea that "phase cancellation" could be a real problem with two mics inside a concertina. Here is a slightly better explanation (in the first part under "Mechanism"): http://en.wikipedia.org/wiki/Phase_cancellation.

 

The effect is quite common on stage and it is annoying, especially for me as a bassplayer: sometimes when I play bass, some notes come out really loud and others are very soft. That happens often in small venues, where the walls are not far away from my amp. The walls reflect the sound and bring it back to where I stand. I get the sound from my amp AND from the walls with a slight difference in time. This means that some frequencies are adding to one another (getting louder) and some are cancelling each other out (getting softer). If I move one meter to the side, the picture can be very different. That´s why I sometimes get complaints from my bandmates, saying their trousers are shaking while I can hardly hear myself ;-)

 

Phase cancellation is a problem when two sounds are both loud. Because the two mics on my concertina are on the ouside, they hardly pick up the sound of the other side.

[David Barnert]

Here's a thought, entirely untried:

 

Attach a little cloth (or metal) ring to each of two small microphones and slip them onto the middle finger of each hand, on the palm side, as far from the finger tip as possible. It shouldn't get in the way of your playing, does not require modification of the concertina, and can be moved to another finger if experimentation suggests the sound would be better there.

[Jim Besser]

I have used various mike systems.Internal mikes are OK if you do not use the air button and when you do it sounds as if you are having an asthma attack.I quickly took the mikes out.

Small mikes fitted to the concertina,to the hand amplify those notes near to the mike and reduced sound from those notes not in line with the mike

Cheap mikes also sound very tinny and requires total switch off of the treble and high use of the base.Not a nice sound at all

.My final solution was two good quality mike's placed about 18inches from each end to allow for bellows movement,fixed on stands and I have never found a better system of amplifying a concertina.

Al

 

After years of experimenting, I've come to believe Alan's system is the best. Internal mics have air problems; the Microvox which I used for years works, but sound quality is not great.

 

I now use two good directional mics on stands, pointed at the ends, individually controlled by the sound engineer. This has produced the best sound - by far - for me, without the hassle of cables and pickups stuck to the concertina, belt packs, etc. I"m actually getting better output than with the Microvox, with much better sound quality.

[Dirge]

 

 

I have used various mike systems.Internal mikes are OK if you do not use the air button and when you do it sounds as if you are having an asthma attack.I quickly took the mikes out.

Small mikes fitted to the concertina,to the hand amplify those notes near to the mike and reduced sound from those notes not in line with the mike

Cheap mikes also sound very tinny and requires total switch off of the treble and high use of the base.Not a nice sound at all

.My final solution was two good quality mike's placed about 18inches from each end to allow for bellows movement,fixed on stands and I have never found a better system of amplifying a concertina.

Al

After years of experimenting, I've come to believe Alan's system is the best. Internal mics have air problems; the Microvox which I used for years works, but sound quality is not great.

 

I now use two good directional mics on stands, pointed at the ends, individually controlled by the sound engineer. This has produced the best sound - by far - for me, without the hassle of cables and pickups stuck to the concertina, belt packs, etc. I"m actually getting better output than with the Microvox, with much better sound quality.

 

 

I'm quite happy to believe that folks, but quality is less important than quick set up and the ability to move around. The mic's have to be ON the 'tina so I can just get up on stage and plug in, and I was very keen to avoid the swan necks sticking out to the sides; both delicate and ugly, I decided.

 

Hence asking about mounting inside; the idea of fixing straight to the rails is close enough to the basic brief to consider too.

[Dirge]

Using only one mic in the middle of the bellows seems to be a very good idea to me. The evenness and the volume would be ideal, also avoiding frettnoises.

That's what I thought.

I was also wondering how a concertina sounds INSIDE the bellows. Maybe it´s great, but there is the possibility of a strange sound just like in a tube.

Again that's what I wondered. Hence the passing interest in accordion players and their doings.

So Dirge, if you are not afraid of the mechanical issues, there is pioneer work to be done. Maybe the cheap mics are just fine.

 

In any case (one or two mics) I would recommend a small mixer at the end of the mics. It has a few advantages: A decent mixer has phantom power, better mic preamps (to bring the mic level up to a usable output), you can mix a mono or stereo signal (with the left-right panning knobs, same as "balance" on stereo system), you can adjust your level and you have the possibility of making a "monitor-mix" for yourself.

 

Another advantage of two mics and a mixer is the possibility of adjusting the level of the right and left side independently (like Geoff pointed out).

Another plus of a single mic' is exactly that; it sidesteps the mixer thing. But this whole business is complex if it's not something you are used to and don't speak the lingo. Electret mic's don't need phantom power is a common 'learned' comment. But they need some power clearly from what everyone else says. I think there's a capacitor that needs charging but after that they draw no current if I've understood aright but it took a while. Then there are definitions of 'phantom power' and explanations of why some things that are called phantom power aren't....

 

The only immediately obvious problem I can see, on bigger duets at any rate, is the way the LH end has fewer frets to help balance the sound; an internal mic' won't see that. But I don't want to take a big duet on stage so that's perhaps a bit of a red herring. But 2 mic's allow you to choose. Tricky.

 

Next 2 questions.

 

1) (basic stuff again) So your normal musician wanting to mic' up an accoustic instrument just supplies himself with pickups or mic's and a battery power supply if he's using electrets; makes sure they have a long enough cable and leaves the sound man to work it out from there? No other considerations; everyone will be able to work with that? Mic', cable, plug, end?

 

2) If the power supply is to take 2 inputs, balance them and combine them what is that actually called so I can try and find something to do the job? How is it described to Mr Google? Or can I make it? A fixed resister on one side and a variable one whose range brackets the fixed one on the other feed? Could it be that simple. (All right that's probably 3 questions)

 

PS quite like your idea too, David. Chewing that one over as well.

Edited April 8, 2013 by Dirge

[Stefan]

Electret mic's don't need phantom power is a common 'learned' comment. But they need some power clearly from what everyone else says. I think there's a capacitor that needs charging but after that they draw no current if I've understood aright but it took a while. Then there are definitions of 'phantom power' and explanations of why some things that are called phantom power aren't....

That´s right. There is a difference between electred and kondenser mics. Electred only need a little power (typically 1,5 V), a small battery is enough. The cable of an electred only has 2 wires. Kondenser mics need more power (between 9 V and 48 V), this is called phantom power. Kondenser mics have 3 wires, +, -, and ground. This connection is called "symmetrical", it´s a "professionel" standard and has the advantage of cancelling out unwanted noises (humnoises for example). The end of a symmetric cable has an XLR or a "stereo" jack.

 

 

The only immediately obvious problem I can see, on bigger duets at any rate, is the way the LH end has fewer frets to help balance the sound; an internal mic' won't see that. But I don't want to take a big duet on stage so that's perhaps a bit of a red herring. But 2 mic's allow you to choose. Tricky.

To avoid dissappointment, you should be aware, that a miked sound is always a different thing than the accoustic sound. I would say that no mic sound can equal the natural sound of a concertina. I agree with Alan Day and others, that the best would be 2 mics on stands, because that gets close to what you would hear if you stand besides the player. Fitted mics give a different sound that is not so natural. When you get so close to the reeds, it´s like hearing with a magnifying glass, if you know what I mean. It´s also a different feeling of playing. I think of it, just as a different sound, like you would get when you plug in electric guitars into different amplifyers.

 

1) (basic stuff again) So your normal musician wanting to mic' up an accoustic instrument just supplies himself with pickups or mic's and a battery power supply if he's using electrets; makes sure they have a long enough cable and leaves the sound man to work it out from there? No other considerations; everyone will be able to work with that? Mic', cable, plug, end?

You should make sure that there is a normal jack (no mini jack) at the end. Or an XLR connection.

 

2) If the power supply is to take 2 inputs, balance them and combine them what is that actually called so I can try and find something to do the job? How is it described to Mr Google? Or can I make it? A fixed resister on one side and a variable one whose range brackets the fixed one on the other feed? Could it be that simple. (All right that's probably 3 questions)

I would say that´s a mixer. Every device that has two (or more) inputs, where you can adjust volume etc. . Some look different and have knobs instead of faders. For example acoustic guitars with pickups or mics have a build in mixer that is combined with the amplifyer.

For electred mics that is very hard to find. Maybe, like it was suggested before, you should get someone who knows how to make things like that.

Because of all these things, I chose to get (ok - more expensive) kondenser mics with an XLR connection that can use phantom power. If you had these, you wouldn´t need a mixer, even though it is convenient. The sound guy could provide you with phantom power.

 

Here's a thought, entirely untried:

 

Attach a little cloth (or metal) ring to each of two small microphones and slip them onto the middle finger of each hand, on the palm side, as far from the finger tip as possible. It shouldn't get in the way of your playing, does not require modification of the concertina, and can be moved to another finger if experimentation suggests the sound would be better there.

Davids idea seems good, but you should be careful about "touch noises". When you touch small mics like these, it´very loud. If you hit the frettboard or anything like that, it would be louder than your playing.

[Jim Besser]

The other thing to remember about internal mics and pickups like the Microvox: the small gauge cables and the connections often produce extraneous noise.

 

I liked the Microvox because I could move around - but moving around often produced pops, clicks and other unwanted noises that became very irritating when amplified by the sound system. I often found myself standing rigidly in an effort to keep the noise down. Stationary mics using heavy XLR cables are much less subject to this problem.

 

And, as others have stated, the sound is more natural.

[Dirge]

Thanks for all your patience with this everyone.

 

SO At the squeezebox end; we don't like a mic' in the bellows, the 'stuck to the rails' concept gets general approval, and Howard J's original build into the ends worked for him (where is he anyway?) We think cheap electrotet's is the way to go.

 

I have duly noted comments about quality and ignored them as too hi-fi for me to be interested; I am more worried by Jim's comments about extraneous noise, but again, it works for others; I think I build it carefully and hope to avoid joints etc..

 

The mixer come power supply is £40 from Microvox; buy that and make the mics myself seemed like the winning answer until I found someone who used to make them himself because he was so outraged at the price. 'Used to' sadly.

 

I know a man who does this sort of thing for fun but won't be able to get at him for a while. In the mean time the bottom line seems to be that although the Microvox setup is as good as you can do in these parameters, sourcing your own saves lots of money but probably won't give away much quality. So if I find a second hand Microvox power supply (that's what they call it) I shall buy it. Otherwise I shall start looking at components.

 

as I said, thank you.

[ttonon]

The mixer come power supply is £40 from Microvox; buy that and make the mics myself seemed like the winning answer until I found someone who used to make them himself because he was so outraged at the price. 'Used to' sadly.

 

 

Dirge, I'm not sure I understand your reason for getting a mixer, but if it's only to combine the signals from two microphones so that the combined result can be plugged into an amp, you can very easily make a passive mixer, in a Y configuration, with the two input cables depicted by the top of the Y and the output is depicted by the bottom of the Y. The low side (often ground) of each cable at the top are combined directly to the low side at the bottom, and the two high sides (hots) at the top are each connected to the high side of the bottom, each through a resistor. The resistors allow each signal to perform independently of the other, providing a kind of "squash" so voltages can move independently. The two resistors should be the same value and are not very critical. I'd suggest values anywhere between one thousand and ten thousands Ohms. You can mount all this in a small aluminum box, with all three cables hooked in, or you can install three jacks in the box, allowing you to plug the cables into the box.

 

Tom

[Wolf Molkentin]

If it's only to combine the signals from two microphones so that the combined result can be plugged into an amp, you can very easily make a passive mixer, in a Y configuration, with the two input cables depicted by the top of the Y and the output is depicted by the bottom of the Y. The low side (often ground) of each cable at the top are combined directly to the low side at the bottom, and the two high sides (hots) at the top are each connected to the high side of the bottom, each through a resistor. The resistors allow each signal to perform independently of the other, providing a kind of "squash" so voltages can move independently. The two resistors should be the same value and are not very critical. I'd suggest values anywhere between one thousand and ten thousands Ohms.

 

Always thought about this (prior to taking up the concertina) without being aware that it can be solved in such a simple way... Thank you for sharing the information!

[Dirge]

 

The mixer come power supply is £40 from Microvox; buy that and make the mics myself seemed like the winning answer until I found someone who used to make them himself because he was so outraged at the price. 'Used to' sadly.

Dirge, I'm not sure I understand your reason for getting a mixer, but if it's only to combine the signals from two microphones so that the combined result can be plugged into an amp, you can very easily make a passive mixer, in a Y configuration, with the two input cables depicted by the top of the Y and the output is depicted by the bottom of the Y. The low side (often ground) of each cable at the top are combined directly to the low side at the bottom, and the two high sides (hots) at the top are each connected to the high side of the bottom, each through a resistor. The resistors allow each signal to perform independently of the other, providing a kind of "squash" so voltages can move independently. The two resistors should be the same value and are not very critical. I'd suggest values anywhere between one thousand and ten thousands Ohms. You can mount all this in a small aluminum box, with all three cables hooked in, or you can install three jacks in the box, allowing you to plug the cables into the box.

 

Tom

 

Thanks Tom; this is the last piece of info I need for the moment. Great stuff; even I understand that. No wonder the chap on the net thought the Microvox item was a rip off. So if I want be able to adjust the balance between the 2 mic's can I make one of the resisters variable with a mid range value about the same as the fixed resister on the other line? And the battery for the electrets goes in series in the output, does it, or do I have to have a separate power supply on the instrument side of each resister?

[ttonon]

So if I want be able to adjust the balance between the 2 mic's can I make one of the resisters variable with a mid range value about the same as the fixed resister on the other line?

 

Yes, although you should be careful to keep the potentiometer and hook up wires small so that they don't become too much of an antenna that would pick up hum. Use the smallest pot, with the shortest hookup leads. In addition, any wires that you use for signal voltages anywhere that are longer than an inch or so should be the center conductor of coax cable, with the shield of the cable grounded on one end only. Small diameter coax is available. Shield grounding is the same for the coax cord that you will use for connection to the amp: ground only one end of the shield. Put the Y joiner at the far end of this (stereo) cord, just before the amp: there's no need for two long cords. With this set up, it may be more convenient to mount two pots on the instrument, one for each mic, because the Y will be mounted far away, where the amp is.

 

And the battery for the electrets goes in series in the output, does it, or do I have to have a separate power supply on the instrument side of each resister?

 

I don't understand. The Y itself is passive - no battery necessary. The standard electret mic hookup diagram shows a battery connected to a current limiting resistor, about 2200 Ohms, with the other end of the resistor split off to the hot wire for the mic and the isolation capacitor, about 1 uF. The other end of the capacitor is the signal wire for that mic, which can go to a pot, about 10k Ohm, and the same battery can be used for both mics. Does that make sense?

 

[Dirge]

I think if I read all this through a few more times I will understand it (I'm not joking, when you haven't a clue this is hard work!) so that's the rest of what I need. Time to find the local electronic components shop and have a play.

 

As for you not understanding, I think you did because you answered my question.

 

Great stuff Tom.

[cboody]

When this works. (No IF in this I'm sure!) some of us would like to see the diagram of hookup and some photos of the end product. I'm willing to give this a try myself with some description in place.

 

One passing thought: When we built my stereo mikes in a similar manner years ago we used a bit of stiff wire and some heat shrink tubing to give the mikes a stiffness. Worked great and helped the look too.

[Geoff Wooff]

I think if I read all this through a few more times I will understand it (I'm not joking, when you haven't a clue this is hard work!) so that's the rest of what I need. Time to find the local electronic components shop and have a play.

 

As for you not understanding, I think you did because you answered my question.

 

Great stuff Tom.

When you consider all the sweat and brain power needed, as well as actually doing it, the Microvox price begins to look cheap. I used to try to do everything myself but of late I realise that life is too short and ( each to his own) let the experts in each field complete their tasks and life is then much simpler.........., even for us cheapskates.