Any experience about B-Band Acoustic Soundboard Transducer

bluetrain

Many seems to put K&K pure maccaferri peizo in their Selmer style guitars. I've heard lot of good about
B-Band Acoustic Soundboard Transducer (AST 1470) which is a similar thing to K&K pure maccaferri but it's not a piezo. I'm wondering has anybody installed this on their selmer guitars?

murrayatuptown

Hei!

I do not have any experience with it but have been reading about these electret pickups for a non-guitar application. You probably know plenty about them since they are from Finland.

In case you don't, or any other readers are interested, they are considered electrets rather than piezos, but both are slightly different variations of the same phenomenon (ferro-electricity).

They have some cool properties, but are apparently much higher impedance than ceramic or polymer piezos. I think they are usually sold with they B-Band preamp, and described as incompatible with other preamps. In addition to the higher impedance, they probably have proprietary connectors which would make connecting them to anything else impractical. If they only come with a B-Band preamp, that solves those issues.

I think the installation manual shows two methods of installation...on a guitar with glued-on bridge and supporting bridge plate underneath, and a guitar with no internal bridge support plate.

On the first style of instrument, they show it placed in the same orientation as the bridge, across the width of the guitar. For guitars lacking such a internal bridge-support plate, they show a possible installation perpendicular to the bridge, along the axis of the neck, between the fan brace bars. See page 5 of the installation manual http://www.b-band.com/uploads/Products/product_19/B-Band-A6T-installation-instructions.pdf

I think this 'vertical' installation appeals the most to me for an archtop or gypsy guitar, but the pressure-sensitive adhesive mounting method would be pretty difficult to do with an f-hole equipped instrument that is already assembled, let alone experiment with re-positioning one. If you are a builder, I think you have a lot more options with the top off the instrument. I'm sure they would work underneath the bridge 'footprint' as well, but the vertical placement appeals to me as being in contact with 'warmer' sounding areas of the instrument.

I've tried to research, a little, who uses B-Band electret pickups. There must be plenty of them, but so far all I found was some Yamaha and Ibanez acoustics. I just saw at least one Ibanez yesterday in a Sweetwater pro gear catalog describing it as having an Ibanez preamp. I don't know if that's a line level preamp following a B-Band one, allowing Ibanez tone controls, or they designed their own electronics to work directly with the B-Band sensor. It's certainly a possibility, but from what I can figure out the B-Band preamp may have as high as 40-50 Mohm input impedance, and you cannot solder these ribbon sensors - they are extremely heat sensitive.

I cannot see in the pictures whether they have 2 or 3 terminals on their pin connectors. If three, B-Band may be using a balanced or differential preamp. I know B-Band's parent company Emfit, makes medical and scientific equipment, and some of the other sensor products they make have three terminals. On the English websites they explain very little, but B-Band seems to do well where the instrument manufacturer has selected them. I have never heard of anyone deciding they couldn't live with one, other than a coupe opinions on an acoustic guitar website. I think they were comparing two different instruments, one with a B-Band pickup and one with another type. Opinions were formed, but who knows what the difference really was due to.

I see and hear opinions from people who do not like in-bridge piezos. This may be analogous to using a bridge pickup vs neck pickup on a dual-pickup instrument. The Bridge pickup has stronger characteristics than the neck pickup due to the physics of where the string vibration is picked up. I think there is some analogy to the sonic difference in where one picks...near the bridge or the neck...in my opinion the sound at the saddle/ bridge where the bridge is at the string ends is harsher and more metallic. Floating bridge is already a lot closer to the fingerboard so a pickup there may sound smoother. Of course, the picking style and traditional tone of
gypsy guitar is pretty bright already, so this will be interesting to hear what you find.

Most piezo-family (including B-Band) pickups inside the bridge (see manual referenced about, page two) or placed under components of the bridge depend heavily on the installation pressure and the B-Band manual discusses experimental shaping of the wood components to affect their coupling between the strings and sensor.

The B-Band A1470 type sensor is not compressed between wooden parts or subject to direct string pressure, and instead is adhesive mounted. I'd say that makes it function more like a contact mic. Inside a floating bridge instrument compared to the Pure Piezo between the bridge feet and body might make the 1470 less bright with less strong a signal (really just thinking here). Also, the 1470 is not probably not really intended for installation under bridge feet, if that was a consideration of yours. I suppose it's possible, but the 1470 and electronics are 'voiced' for the intended method and location of installation (adhesive-mount inside instrument).

Looks like the Pure Piezo IS much more readily accessible (for changes) than an internally mounted A1470. The more I think about it, the less practical '1470 seems in an already built Selmer/Maccaferri style instrument. No telling how much room there is internally under the bridge either, without looking or seeing a drawing.

I hope that's useful opinion, assuming you are still awake after reading this!

If no one reports back here their experience with A1470 in this type of instrument, and you hear of such experience elsewhere, would you please consider reporting that back here?

I'm also curious if the 1470 refers to 14x70 mm active sensor area.

I personally would like to try the '1470 internally, perpendicular to a floating bridge for my own curiosity, rather than assuming it had to be in the same orientation as the bridge. Of course, this assumes access to the interior is available. My feeling (in theory) is that bridge-foot installations get more 'string sound' than 'body sound', and this may also be true of embedded piezos and the B-Band UST type.

Have you asked B-Band, or maybe someone like AJL about this?

I looked at the AJL site, and it looks like their gypsy guitars are all acoustic. The only pickup I saw on the site was an archtop floating single coil type.

Maybe there are reasons...

Onnea!

Murray

Russell Letson

I had a B&B with pre-amp installed in my Dunn Daphne. The transducer is just in front of and parallel to the the brace that runs under the bridge. (My tech guy did a bit of fiddling to find the best spot.) To my ear it's a pretty natural sounding pickup, though a bit more feedback-prone than the Baggs Dual Source rigs in my flat-tops. It's also somewhat sensitive to handling noise, but that bug becomes a feature whan I want percussion effects. I usually run it through a Baggs Para-DI for volume control, and that does a lot to tame feedback and reduce the bass end.