Problem with Fishman Rare Earth Blend Pickup

[Guest]

For many years I've used a Fishman Rare Earth Blend Pickup on my acoustic guitar going into one of those small Snark pedal tuners, then out to my amp/PA. Worked great.
I've not done any gigs for a few years but recently started up again and the tuner stopped working, dead as you like. I recall it was getting unreliable before.

So I tried a friend's pedal tuner and no signal came through, same with another pedal tuner I tried, both worked fine with other guitars. Mmm, weird, so I picked up a new Snark tuner, same model as before and that works but when you hit the pedal footswitch I've a huge bang when you turn it on/off.
Tried another guitar through the pedal tuner, no bangs.
I've changed the battery, replaced all my cables and pulled out the fishman to plug it in and wiggle the wires, can't find any loose connections. Any ideas?

[Hugh Robjohns]

The kind of big bangs you describe are often caused by DC volts on the audio line.

Do you still get them if you take the batteries out of the Fishman?

If not, the chances are there's something amiss with the Fishman electronics.

[Guest]

The kind of big bangs you describe are often caused by DC volts on the audio line.

Do you still get them if you take the batteries out of the Fishman?

If not, the chances are there's something amiss with the Fishman electronics.

Thank you Hugh, I will try it without the battery but I assumed it needed power to work. I guess it's looking like it's reaching end of life, it's 10 years old or so. Shame, if I don't use the tuner it still works fine.

[Wonks]

The pickup needs the power to work, but testing without the battery shows whether it is a preamp issue or not. If you still get the bang with no battery, it can't be battery DC (where it shouldn't be) causing the problem.

[Guest]

The pickup needs the power to work, but testing without the battery shows whether it is a preamp issue or not. If you still get the bang with no battery, it can't be battery DC (where it shouldn't be) causing the problem.

Ok, I'll test it tomorrow without the battery and report back. Thanks

[Wonks]

What's the fit of the endpin jack like? You can get the screw-on strap button fitting coming loose so it stands proud of the end of the endpin, rather than the endpin sitting flush or slightly proud of the strap button ('slightly proud' illustrated below).



If the jack can't plug fully into the socket, being held away by the strap button, you can get intermittent or zero contact with the tip, and the ring contact may or may not close the battery circuit, or may possibly bridge the tip and sleeve on the jack.

It's probably not that at all, but still worth a check from time to time.

[Guest]

Wonks, I so wanted it to be that, made a lot of sense but sadly not.

So I took the battery out and no output at all but no bangs. Figured time to buy a new one but just thought I'd have one more go at fiddling with the socket as over the years it would work its way loose and I'd always be twisting it to tighten which no doubt put strain on the cable. However, one more test and no bangs! I can't see any loose connections but I've put it back in place and so far still no bangs, Hugh was right so thank you guys, you've just saved me £200. At least now I know what the issue is and if it happens again I can get someone to look at the connections. Huge thanks.

[Hugh Robjohns]

Intriguing! I'm pleased its now working again and you know the solution and what to look for to anticipate future problems.

Without seeing it in person it's impossible to say for sure what's going on, but I will hazard a guess that the grounding path to the output goes high impedance when the socket works loose, and that allows the output to develop a DC bias.

That, or you disturbed something when removing/replacing the batteries. (Maybe one battery was previously not fitted quite right?)

Anyway, glad it's solved.

[gerrit.verhoeff@gmail.com]

Hi is iT possible to solder a container for two AA batteries onto the Fishman Rare Earth Blend Pickup, so that i don’t need to take iT out all the time, to replace the batteries? Or wil iT be to powerfull?

[adrian_k]

2 x AA batteries will provide roughly the same voltage as the button batteries in the pickup, so won’t be too powerful.

However, the button batteries provide a constant supply over a longer period, while the AAs’ voltage will drop as they discharge, which is not ideal.

I’m surprised you’re having to change the batteries often enough for it to be a problem?

[Sam Spoons]

Agreed, unless you are leaving the guitar lead plugged in the batteries should last at least 12 months (I have a couple of Rare Earths including a Blend).