Amplification of an Acoustic Accordion Questions

[Thomas N]

I have a couple of accordions with a 1/4" output jack for external amplification. One has passive old-school electronics and the newer one has the nicer, battery-powered Sennheiser active electronics.

I have an older JBL EON speaker that I wanted to test out with these accordions. I don't think I've ever had the need to amplify these acoustic accordions and when I tried it out it doesn't work. My FR-8X digital accordion works perfectly with the EON speaker (that's what I bought it for).

I believe this probably has something to do with the balanced/unbalanced aspect of the acoustic accordions. I believe what will solve my problem is either:

1) Purchase a keyboard/guitar/bass amplifier.

2) Purchase a small mixer or DI Box and run the accordion into that, and the mixer/DI Box into the JBL EON.

I'd rather not buy another amplifier. I know that it's not a problem with the accordion since both accordions don't work with the JBL EON.

 

[JeffJetton]

I have one of those EONs myself and actually use it primarily for a keyboard amp! Its great. I agree that getting a whole new amp would be overkill.

Anyway, for the active Sennheiser, youd think it would just work fine. If it doesnt, maybe theres something wrong with the electronics? Make sure you have a good battery in there, of course.

Another thought is that maybe its putting out a mic-level signal rather than a line-level signal, in which case you might need like this to route it to the XLR (mic) input of your EON.

For the passive one, Id guess that you will need some sort of pre-amp to get the signal to the level your EON inputs can use. It probably wont even be at basic mic-level without some sort of boost (although you might hear something if you rigged it up to the XLR input). That could take the form of a mixer with 1/4 inputs to a built-in preamp, or as part of an active DI box (dont get a passive DI), or as a stand-alone preamp... like they make for acoustic guitars (LR Baggs, etc.)

 

[debra]

It's a bit strange that it does not work at all. The accordion mics produce microphone output which is a much weaker signal than the line output of the Roland. But even the weak signal should trigger the speaker into doing something. Of course when you play the accordion you won't be able to hear it. Someone else needs to have their ear against the speaker to detect the faint sound that you should still be getting.
So what you should be needing is a microphone pre-amp. I can recommend the Bose Tonematch engine (for which you will need an external power supply as you are not using it with a Bose amplifier). It has 4 inputs, can do reverb and can be set to "accordion" for better sound output when used with an accordion. It takes the 1/4" jack input and has 1/4" jack output.

 

[Thomas N]

I appreciate the replies from both of you. Paul - I think you hit the nail on the head. There is some sound coming out of the EON but it is very minimal. The sound of the actual accordion itself overpowers the amplifier. I'll take it into a music store and run it through a couple preamps and see what happens.

 

[JerryPH]

If your accordion uses the passive old-school electronics, that means it uses dynamic electret mics that are powered by a magnet. These magnets have lifespans, usually somewhere in the 5-10 year range, then they start loosing quality of sound until they are so weak that they cannot generate enough current to create any sound at all.

I was in the same boat myself, and when I went to Hohner looking for replacement parts, they say nothing like that has been made for several decades, however... they still do make standard hand held microphones that use dynamic electret mics that require no phantom power, nor do they even require a battery and there are a couple of good and bad points to this.

The good... no batteries required, cover enough range to adequately capture the sound of the accordion, its really hard to cause feedback with these mics, especially if they are inside the accordion bellows and basically a zero maintenance item.

The bad... volume output is lower, so when you try to hook them up to an amp, they sound fine, but the moment you hook them up to a mixer, you note that you have to raise the output of the pots to the point that it introduces hiss into the system. Yes you can use preamps... but that is $100-$200 better spent elsewhere.

If your mics were like mine (meaning dead), you have to replace them. I just happened to have several $10-$15 hand held mics that were of the dynamic electret kind. I broke them apart down to the capsules and replaced the mics of my accordion with these and they worked pretty well... NOT as well as a properly designed modern powered mic setup, but they sound as good as they factory originals, so I cannot ask for more than that for now. In the future, I do plan to add something much nicer (likely Sennheisers with 10 mics for the right hand and at least 3 or more for the left hand made by HATOOLS)

Right now, if you can get them all to work, the big thing that you need is some kind of mixer that lets you balance out the volumes of each input and balance it all out. Mixers can go from mild to wild, there are answers out there for nearly any budget and any need.

 

[Thomas N]

Thanks again for the advice.

The 930 Van Damme is not producing any sound and now I understand why. Ancient electronics and they are passive.

The 960 with the Sennheiser system is finally making sound. There is a lot of scratchy static and I've tried 5 different instrument cords. Some were 1/4 inch to 1/4 inch and some were XLR to 1/4 inch. Brands were Monster, Cable Matters and Hosa. I suppose it's the actual physical connector on the 960 that I will need to take apart and re-solder.

 

[debra]

Thanks again for the advice.

The 930 Van Damme is not producing any sound and now I understand why. Ancient electronics and they are passive.

The 960 with the Sennheiser system is finally making sound. There is a lot of scratchy static and Ive tried 5 different instrument cords. Some were 1/4 inch to 1/4 inch and some were XLR to 1/4 inch. Brands were Monster, Cable Matters and Hosa. I suppose its the actual physical connector on the 960 that I will need to take apart and re-solder.

A weakness in the design of the Sennheiser system (and also the Microvox) is that the jack plug acts as an on-off switch. So when you pull the plug the mics are off and no power is consumed. But using the plug to conduct the current (to switch on) in the end always ends up failing and causing static and/or more serious plops or bangs. As the Microvox has a volume knob that also switches off the power I disabled that switch function in the plug. But with the Sennheiser system you cannot do that unless you replace the volume knob by one that also has a power switch (and then route power through it).
With systems like the Sennheiser the behavior also becomes a bit unpredictable when the battery is low. The volume can simply drop and finally cut out but it is also possible that it starts creating lots of static hiss. Because the battery is inside people tend to not check it regularly. I once was called in for an emergency when an orchestra was about to start a performance and their bass wasnt working. I rushed to the scene with a (9V) battery and other repair gear. Turned out they had no idea there was a battery hidden under the grille. I replaced the battery and voilà it came back to life. Concert saved!

 

[acordiansam]

One thing You might want to ck. A lot of boxes were set up for stereo plugs. A tip ring sleeve. You could be shorting out the plug with a mono plug. Just a possibility?

 

[Alan Sharkis]

Batteries in those systems cam fail if the volume controls on the accordion are not set at minimum. Accidentally turning them just a little bit past minimum will cause them to drain. I know, I've been there. I guess you can't fit a volume control with a switch on it into the typical locations on an accordion grille because there isn't enough clearance for the switch.

 

[Thomas N]

All excellent suggestions!!!! It has been driving me crazy trying to sort out the static. Seems to be concentrated on the bass side as when I turn down the bass volume control most of the static goes away. I had no idea the batteries drained with the volumes not set to minimum. That would explain why my new 9v batteries don't seem to last long. In fact, that's what I did to get it working somewhat. I replaced a battery that I know I put in only a few weeks ago. I thought it might have been a bad battery.

I'll also check out the stereo plug. All cables I'm using are mono - I guarantee that.

You all have been extremely helpful. Thank you.

 

[debra]

Just to be clear, mics with battery power will continue to use power regardless the volume setting. The power drain only stops if the volume control has an on-off switch, but as Alan said, there may not be enough room behind the grille to install a volume control with switch. That is why often a power switch is incorporated in the jack plug instead. (I have seen such switch only incorporated in mono plugs though, not stereo.

 

[acordiansam]

Most preamp's set ups I have seen turn on as the core is plugged in. Don't leave the cord plugged into the accordion that should extend your battery life. Also if I am correct you need a cord with one stereo end going into two mono plugs. One for bass one for treble side. That way you can use different EQ and volume for each side if needed.

 

[kimric]

The Musitech mic system (commonly called Sennheiser whether it actually equipped with said mics or not) pretty commonly has problems with the 4 pin plugs that are used, and the wires that go through the bellows. You can test for the bellows wires by just moving the bellows without playing a note , if you get a crackle when you do it is often the bellow wires. The solderless single use plug that is used under the grill is often a source of problems as well, as the wires break off of the plug where they are pinched into the contacts. The 1/4 plugs can get worn but I find this is only occasionally the problem. The plug getting rotated and the wires coming off is more common.

The older mics in accordions are mostly crystal mics and generate a signal much the same way a modern lighter makes a spark when you push the button an strike the crystal http://hyperphysics.phy-astr.gsu.edu/hbase/audio/mic3.html . The crystal can deteriorate with age and it is often necessary to swap out mis to get a matched volume set. Both these systems should make plenty of noise on anything that is designed for a electric guitar level signal. You may have anything from 1-7 crystal mics in your instrument.

Check and see if there are actually any mics in your older accordion, sometimes they have been removed. Also many were set up for stereo output and putting in a regular cable will one channel to get grounded out. Check and see if the wiring is not decayed and crumbling.

I found that tube amps and hybrid tube amps give a better sound with the accordion in general, and a bass amp is a good second if you cant get a good keyboard amp. Regular guitar amps dont handle the accordions lows that well ,and make the crystal miss sound metallic.

 

[Thomas N]

The Musitech mic system (commonly called Sennheiser whether it actually equipped with said mics or not) pretty commonly has problems with the 4 pin plugs that are used, and the wires that go through the bellows. You can test for the bellows wires by just moving the bellows without playing a note , if you get a crackle when you do it is often the bellow wires. The solderless single use plug that is used under the grill is often a source of problems as well, as the wires break off of the plug where they are pinched into the contacts. The 1/4 plugs can get worn but I find this is only occasionally the problem. The plug getting rotated and the wires coming off is more common.

The older mics in accordions are mostly crystal mics and generate a signal much the same way a modern lighter makes a spark when you push the button an strike the crystal http://hyperphysics.phy-astr.gsu.edu/hbase/audio/mic3.html . The crystal can deteriorate with age and it is often necessary to swap out mis to get a matched volume set. Both these systems should make plenty of noise on anything that is designed for a electric guitar level signal. You may have anything from 1-7 crystal mics in your instrument.

Check and see if there are actually any mics in your older accordion, sometimes they have been removed. Also many were set up for stereo output and putting in a regular cable will one channel to get grounded out. Check and see if the wiring is not decayed and crumbling.

I found that tube amps and hybrid tube amps give a better sound with the accordion in general, and a bass amp is a good second if you cant get a good keyboard amp. Regular guitar amps dont handle the accordions lows that well ,and make the crystal miss sound metallic.

Thank you for this information! Thats exactly what it is. I thought it was in the bass mechanism because it only seems to happen when Im playing the bass. But now I understand that its the movement of the bellows that is doing it. Thats why when I play the bass alone it is more exaggerated.

Ill open it up and take a look. Is it usually just a reconnection that needs to be established or do the wires wear out? In other words, is this something I should attempt on my own with average electronic skills? Ill at least take a look and appreciate the advice.

 

[kimric]

The wires seem to wear out as they get flexed constantly and eventually fatigue. I replace the harness with a Molex plug with crimp connections to prevent further problems. Musitech is pretty bad about support so I just make my own cables. You have to whittle a tab off of the male end but then you have a industry standard plug that is easy to replace.