Tech Tips

Combining the Acoustic Matrix and Rare Earth pickups
Did you know that you can combine the Acoustic Matrix active undersaddle pickup with the Rare Earth series of active magnetic soundhole pickups to create a new dimension in sound? This combination allows you to power both active systems from a single 9-volt battery and results in a T-R-S (Tip-Ring-Sleeve) output. The Acoustic Matrix signal on the tip of a stereo jack, and the Rare Earth signal on the ring, will allow you to send both signals simultaneously to separate amps or channels in a mixer to create your own acoustic sound. This modification requires the new Switchjack Equipped version of either the Acoustic Matrix Natural 1 or Natural 2 and any Rare Earth model pickup. We would be happy to E-mail the wiring schematics for this modification, or you can simply check it out in the Wiring Diagram section of our website.
Adjusting Phase settings on the Acoustic, Bass and Pocket Blenders
There are always a lot of questions regarding the proper way to set the phase buttons on the external Blenders. An easy way to achieve the proper phase setting is to start with the mic signal only. Listen as you switch back and forth with the mic phase button. One setting will give you a fuller, richer sounding signal with a little more bass response than the other position. This will be your in phase switch position. You then simply set the pickup channel the same as the mic. If the button is in the out position on the mic channel, it should be out on the pickup channel. Playing in phase will allow you to get a richer more feedback resistant natural sound from your instrument.
Adjusting the microphone level on the Prefix Stereo Blender
There are frequent questions about controlling the balance between the undersaddle pickup and the microphone level with regards to the Prefix Stereo Blender. Balanced output levels between the microphone and pickup will allow greater control over your sound. We have provided a trim control potentiometer on the underside of the preamp to better enable you to balance these signals. To adjust the microphone signal, set the BLEND slider to the center position and, with a small screwdriver, adjust the potentiometer until both the microphone and pickup levels are balanced.
Adding an internal connector to the Rare Earth series pickups
We occasionally receive requests to suggest a solution for the problem of having the Rare Earth series pickup permanently mounted in a guitar while maintaining the ability to remove the pickup when needed. This is possible by placing a connector in line between the pickup and the endpin jack. We do not provide the parts but we suggest using a high quality shielded stereo connector, which can be secured inside the instrument. Make sure that all solder connections are precise and shielded for optimum audio quality. Once the connector is installed, you can easily unplug the pickup when it is not needed. This modification also makes it possible to use a single Rare Earth pickup on multiple instruments.
Will the Powerchip allow me to blend my Powerbridge and magnetic signals onboard the guitar?
The answer to this is yes and no. The function of the Powerchip is to buffer the Powerbridge signal to better match up with the magnetic output. This impedance matching allows the Powerbridge and magnetic signals to be mixed to a mono or stereo output depending on the cable used. A mono cable will give you a combined piezo/magnetic signal to the tip of the output jack and a stereo cable will give you the magnetic signal on the tip and the Powerbridge on the ring. The Powerchip is not a blend pot, but a volume pot for the Powerbridge only. To adjust the amount of blended Powerbridge and magnetic signals, the Powerchip and the original magnetic volume controls must both be used.
Alternate BP-100 installation
To all BP-100 owners that have lost a Felted U-Clip, there is an alternate method of attaching the pickup to your bass bridge. Since the U-Clips can be a tough item to locate at your local Fishman dealer, you can use a standard hot-melt glue gun and glue stick as a temporary or even permanent solution. Make sure you have a nice flat surface area on the bridge to affix the pickup. A sanding block is the best tool for this. Once the area is sanded flat, apply a liberal amount of hot-melt glue to the back side of each element and affix to the bridge. Remove any excess glue and use a clothes pin (or the remaining U-Clip) to hold it in place until it dries. Once dry, youre all set. To remove the pickup, just heat it up slightly with your average blow dryer and it will come right off.
Using the Powerchip on an Archtop Guitar
We have periodically been asked to suggest a way to blend the Fishman Archtop Piezo replacement bridge signal with an existing magnetic pickup on an Archtop guitar. We have found the Powerchip to be an excellent solution to this problem. The Powerchip was initially designed to allow onboard blending of magnetic pickups with our Powerbridge Electric Guitar Piezo Bridge. It will also work on the Archtop and other similar blend situations. Two things to remember are, one, the Powerchip volume pot acts only as volume control for the piezo bridge. It is not a blend pot (See tech tip #5 for details on Powerchip operation and output scenarios). Secondly, you must have access for a 9-volt battery which is needed to power the Powerchip. Once installed, youll have the option of a mono mixed signal or a stereo T-R-S signal from the instrument. The Powerchip has proven itself to be a diverse product that will open up audio possibilities in many instruments.
Tune-o-matic Powerbridge Pickup tips Now that our Tune-o-matic Powerbridge pickup is online, here are a few things to consider before getting started.
Nashville vs. ABR-1 format
The Tune-o-matic Powerbridge conforms to the footprint of Gibsons Nashville style bridge. If you are replacing an old style ABR-1 Bridge with a Powerbridge, have your repair-person plug and re-drill the post holes on the guitars top to fit the hardware and hole spacing for the Nashville bridge.

Long Shaft Powerchip
We are now offering a special Powerchip with a length shaft, specifically for Les Paul Tune-o-matic Powerbridge users. The potentiometer for this Powerchip will retrofit perfectly into Les Paul models with long shaft volume and tone controls.

What modifications are required?
The Tune-o-matic Powerbridge Pickup can install without any major modification to a Les Paul. You will have to file a small notch in the pickup-mounting ring to route the Powerbridge wire. If you want to keep the cosmetics of the guitar absolutely untouched, we suggest that you purchase a new pickup-mounting ring to replace the original.

Choosing between the Acoustic Matrix Natural I or II
We offer our Acoustic Matrix Active Undersaddle Pickups with two preamp voicings, the Natural I and Natural II. These 2 preamps will accommodate different instruments and playing environments. This Tech Tip will give you a quick review on choosing the correct version for your guitar.

Natural I
Choose the Natural I if you want more bass response than the guitar naturally produces. Typically, the Natural I is a good match for players with non-scallop braced instruments (especially smaller sizes), who perform solo or in small all-acoustic ensembles at relatively low volumes. If your instrument is at all prone to feedback, you may want to check out the Natural II.

Natural II
This version is designed for instruments with lots of naturally deep bass like a big scallop-braced dreadnought. Also, if you play in a band with an amplified rhythm section, the Natural II will cut through and deliver the goods. Because of its ability to reject low frequency feedback, the Natural II is the choice of touring performers who play large venues.

With the correct version of the Acoustic Matrix pickup system in your guitar, playing feedback free and with great tone is as easy as plugging in.

Why dont any of our preamps have a pilot light?
We made a deliberate decision many years ago to not include a pilot light on any of our battery-powered electronics. Weve got good reasons. First of all and most importantly, a pilot light (LED) will unnecessarily reduce the life expectancy of a battery. Since we want to guarantee you every possible hour of use from each battery, a pilot light would be wasteful.

We also think that when it comes to the visual display, playing your guitar should be like driving a car. You dont need a light to tell you that the motor is running, right? So why would you need one to tell you your preamp is working? If you run with this analogy, it can help to have a dashboard warning light come on when youre low on gas or when you overheat the engine. Enter the Low Battery (and/or) Clip warning LED featured on many of our products. We include warning lights so that youll know ahead of time if youre about to get into trouble. Our Low Battery LED Is triggered to activate with about I hour of battery life remaining. Our Clip light blinks when your pickup overloads the preamp and is telling you to trim down the preamp input.

Can my Acoustic Matrix pickup element be cut to fit any length slot?
The Acoustic Matrix undersaddle pickup element comes in a standard length of 2.650 (67.3mm), with a sensing area of 2.500 (66.55mm), which will fit into 99% of the acoustic guitar saddle slots and string spacings that exist today. For custom length slots, we are happy to manufacture pickups on a special order basis. Due to the nature of the manufacturing process, the Acoustic Matrix pickup cannot be cut to fit once it is made. Saddle slots over 3 can be accommodated with a 2 piece saddle as we cannot manufacture a one piece pickup over 3 in length. Please see your local Fishman dealer for pricing and ordering information.
How much wood can be taken off the top of the Mandolin and Archtop replacement bridges for fitting and intonation adjustment?
We recommend removing no more than 5/32 of material when fitting either of these bridges to your instrument. There are 2 reasons for this. One is that the string volume may be uneven and unpredictable if the strings end up too close to the embedded pickup element. Secondly, removing too much material can weaken the upper part of the bridge considerably and may cause structural damage when under proper string tension. As always, we recommend professional installation for these products whenever possible.
Which Rare Earth Pickup is best for me?
With the addition of the new Passive Rare Earth soundhole pickup, the Neo-D, there are now more choices than ever to get a great sound from our Rare Earth series. This Tech Tip will run down the options for you. The Neo-D fills the gap from the beginning player to the cost conscious professional for a great amplified sound. No battery or additional cable is needed for this passive, single coil magnetic pickup. It comes equipped with a low-capacitance cable w/ 1/4 plug. The Active Rare Earth series begins with the Single Coil. For those of you requiring a brilliant cut-through tone, this is your pickup. For a noiseless signal with richer tone, check out the Humbucker. For the ultimate blend of an active magnet and a high quality condenser mic, the Rare Earth Blend or Custom Blend will do just fine. All the active Rare Earth pickups come with our Switchjack stereo endpin jack, which can be used hanging out of the soundhole, or installed as a permanent endpin jack with strap button. For all of you southpaws out there, ask your dealer about the left-handed versions of these popular pickups.
Can the Pro-EQ Platinum Bass be used with an electric bass?
Absolutely. The new Pro-EQ Platinum Bass preamp/DI was designed for any bass, acoustic or electric. In fact, the Platinum Bass was beta-tested by some of the music worlds finest electric bassists. We received a resounding thumbs up from all and the result is one of the most important Fishman product releases in some time. If you play bass, acoustic or electric, then this is the preamp for you. With an unmatched feature set and exceptional tone shaping, this product will enhance any electric bass signal.
After having an Acoustic Matrix pickup system installed in my guitar, I am noticing that some strings are louder than others. Is there something wrong with this pickup? How can this problem be solved?
It is virtually impossible for an Acoustic Matrix pickup to be more responsive in some areas and less responsive in others due to a defect in the pickup. The reason for unbalanced string volumes is a lack of even down-bearing pressure on the pickup under the weaker strings. This translates to lower volume for that particular string. This problem can be caused by many things including an uneven saddle slot, a saddle with an uneven bottom surface, a guitar that is "belly-up", a lifting or loose bridge, poor fit of the pickup in the saddle slot and an insufficient break angle of the strings over the saddle. A qualified repair shop should be able to identify which issue or issues you are dealing with and make the appropriate corrections.
Can the Resophonic pickup be used with my biscuit style resonator?
Since most of the Tech Tips posted on our website are initiated by customer emails concerning our products, I wanted to take this opportunity to give you the scoop on the Resophonic pickup. Weve had a lot of questions regarding the use of this product with both biscuit and spider type resonators. The good news is that it will work with both and comes with complete mounting instructions for either type of resonator. You can also install it passively or with an onboard endpin mounted preamp for a boosted and buffered active signal. Finally, a great alternative to microphones when amplifying a resonator.
Whats the Difference between the Martin Gold Plus and the Acoustic Matrix?
In a previous Tech Tip (see Tech Tip #10), we discussed how to choose the correct Acoustic Matrix system for your guitar. The differences between the Natural 1 and the Natural 2 were explained in detail to help you make the correct choice for your instrument. Here, we will answer a common question about the Martin Gold Plus. The Martin Guitar Co. has been a great friend and business Partner with Fishman for many years. They market and sell many Fishman products under the Martin Brand name. In the case of the Acoustic Matrix, the name Gold Plus is used. The Martin Gold Plus is the Acoustic Matrix Natural 1, narrow format 3/32, and the Martin Gold Plus Max is the Acoustic Matrix Natural 2, narrow format 3/32. No tricks, no gimmicks, just the same quality components with different names. The Fishman version also offers the option of a wide format, 1/8 pickup for wider saddle slots. Hope this clears up any remaining questions about this issue.
The SBT Soundboard Transducer - A new twist on pickup/microphone or dual Pickup combinations
For years now, one of our more popular pickup combinations has been the Acoustic Matrix Natural 1 or 2 active undersaddle pickup along with the Crown GLM-200 mini condenser mic run through our Pocket Blender. A great sounding system if I do say so myself (and I do). A new configuration that seems to be gaining popularity is to replace the microphone with our SBT Soundboard Transducer. When attached to your instruments soundboard, the SBT can provide a full and natural response that can be very effective when mixed with an undersaddle or even a magnetic pickup. The SBT is also an economical choice for a second source pickup. There is also a school of thought that the SBT can be a very effective main signal source when combined with the Crown GLM-200. Whether you are using the Pocket Blender or another mixer to combine signals, the choices are getting more interesting for dual pickup combinations all the time.
Whats the best position to mount the Full Circle Upright Bass Pickup?
Our Full Circle Upright Bass Pickup is encased within a height adjuster wheel. The post that holds the wheel in place is threaded (for precise adjustment) on one side, and is not threaded on the other.

Weve had many people ask if there is a tonal difference between threads up and threads down mounting position. The answer is yes, there is a subtle difference, but you should get satisfactory results either way.

Mount the Full Circle threads down, and the hot side of the pickup faces the strings. This translates to more defined articulation and attack, with a slight emphasis on string sound. When mounted threads up, the hot side of the pickup faces the body of the bass. Youll get a more wooden acoustic tone this way, with a more rounded attack and less edge. Which way is better? Its too subjective a decision to say one is better than the other, but our local bass repairman tells us that most of his customers prefer the sound of the pickup in the threads up position.

Adding a passive volume pot to a Fishman Powerbridge
If you already have a Fishman Powerbridge on your guitar, you may also have one of the original 5 Meg passive volume pots that was included with the bridge. We no longer provide the 5 Meg pot with our Powerbridges but rather, we now include a diagram to upgrade the performance of your Powerbridge with a standard 250k pot. We feel this is a better option and are now making this modification available in the installation instructions included with the Powerbridge, as well as featuring it here in the Tech Tips section and the new Custom Wiring Diagram section of our website. This passive circuit has a smoother taper and more even response than its 5 Meg predecessor. It will attenuate the Powerbridge to match up better with magnetic pickup levels. Components for this circuit can be easily found at any electronic parts retailer.
Adding a Rare Earth to a guitar with an onboard preamp/EQ
This Tech Tip will explain adding a Rare Earth Active Magnetic soundhole pickup to any guitar with a mono output onboard Preamp/EQ. You will not be able to control the Rare Earth with the onboard preamp, but it will give you the Rare Earth signal on one terminal of the Stereo Jack. You can choose whether to add the Rare Earth to the ring or give it the primary tip position. You will be able to access both pickups with a stereo Y cable, or choose just the tip terminal pickup by using a standard cable. This modification is not possible with systems that have an existing T-R-S stereo output, such as the Prefix Stereo Blender.
My Acoustic Matrix pickup is balanced and sounds great, but Im noticing a hum that sometimes disappears. I can make the hum disappear when I touch the endpin jack. Is this an electronic problem?
A humming pickup is almost never the result of an electronic problem, but rather the result of issues surrounding the installation of the pickup in the saddle slot. The most obvious reason to look for is a tear or rip in the foil wrap of the pickup. This material is the shield of the pickup and when disturbed will cause the pickup to hum. Another reason for hum is a poor fit of the pickup or saddle in the saddle slot. The Acoustic Matrix pickups ground properly when under correct pressure in the saddle slot. Anything than may impede the pickup from being properly compressed in the slot, can be a cause for hum. You should be sure that the pickup drops easily into the saddle slot. It should not be forced in to a tight slot. Also, be sure that the saddle slides easily into the slot while not being too loose. Because the bridge is made of wood, it will expand and contract with regard to humidity levels and temperatures. This movement can affect the pickup and saddle fit, which can result in the hum being intermittent. While this is the most difficult type of hum to correct, with a proper fit of pickup and saddle, it should be a rare occurrence.
What is the best way to add a volume and tone control to an Acoustic Matrix active undersaddle pickup?
Glad you asked. It just so happens that the new Fishman VTB volume, treble and bass circuit works perfectly in that application. This new circuit has a discreet shoulder mounted installation profile with 2 control pots. One is a dedicated volume pot and the other is a dual concentric treble and bass pot. This controller not only gives you fingertip control of your volume, but also the ability to boost or cut treble and bass frequencies to dial in your unique tone. It works well with either the Natural I or Natural II Matrix systems as well as the Martin Gold Plus and Powerjack. This item can be purchased through any local Fishman retail dealer and to make it even easier to get, here is the part number: ACC-MAT-VTB.
I never received Aura software or USB cable with the factory installed Aura on my new guitar. How do I get these items to use the software?
In the case of an OEM Aura, installed at the factory, we have already created images from that exact guitar model and the manufacturer (along with Fishman) has selected the best resultant matches to include on the factory device. The factory Fishman product is then locked with those images. Why? Because there are no better images to be gained. Hooking the product up to the computer to download images can only create worse results, not better. So, the factory installation of your Aura product is already optimized for your guitar, and can’t (and shouldn’t) be connected to your computer for alternate images. For more information, see our description of how Aura technology works.
Fishman’s list of Aura Images includes guitars, mandolins and other instruments. Does that mean I can use an Aura pedal to make my guitar sound like a mandolin?
Short answer: No. Long Answer: first of all, a bit of clarity on what Aura imaging does is in order. Basically, we record an instrument (let’s say, for the sake of argument, a Dreadnought 6 string acoustic) with several different recording microphones and the guitar’s Matrix under saddle pickup, all at the same time. Each microphone output is compared to the pickup output using a computer algorithm which is able to identify the difference between the pickup sound and the microphone sound. This difference becomes the image. If you play the Dreadnought with the Matrix under saddle through an Aura unit with this image loaded, the Aura is able to recreate the sound of the high quality studio microphone, using only the pickup signal. If you plug in a different guitar (say a Nylon string guitar) using the Dreadnought images, the result would not be for Classical to sound like a steel string acoustic. It would just sound bad. So, when people put an Ellipse or Onboard Aura in their guitar, aftermarket, or use one of our pedals, there must be some way for them to look through our images to find the instrument which most closely matches theirs. That is what the software is for. Usually good results start to happen when the body shape and top woods are well matched. The results improve with more matching characteristics. In a perfect world, we would have the exact model of guitar. Some folks take advantage of our custom shop, and have images created from their specific guitar, creating an exact match. Of course, an exact match is the best possible option.
I see I can get a Matrix outfitted Fishman system for my guitar in Wide, Narrow or Split formats. Which do I need?
This designation refers to the width of the saddle slot. Some companies, like Martin, have traditionally used a 3/32” saddle slot, which we call Narrow. Others, like Gibson, use a 1/8” slot, which we call Wide. Split format is for less common instruments made by some companies, such as Lowden, which feature two saddles, one short one for the E and B strings and a longer one for the remaining four strings. If you are unsure which model you need, measure your saddle carefully, using calipers, or simply show your guitar to your installer. They will usually be able to see right away which size will fit your instrument. If there is any doubt, a Narrow pickup can fit in a Wide pickup slot and work reasonably well, but Wide pickup can never fit in a Narrow slot.