Help with terrible sounding K&K Twin Mandolin Pickup

[eelcobeckers]

Some interesting bits of advice there. I suppose before i buy a preamp i might mess sround with a few DI boxes. I'm have 5 different ones, both active and passive, including some better quality ones like the radials and the BSS. I suppose that will guve me an idea where the problem might lie. I dont think the pickup is faulty though. It works fine,just sounds bad!

[varmonter]

Eelcobeckers are you going out of the bss di with a 1/4 inch
Cord to the mixer or a mic(xlr) cord?

[Astro]

If you plan to gig around town with it, there is some advantage to going the preamp/eq route. The advantage is you can determane what eq settings sound best and take it with you to every House PA so you can go with a pretty flat mix on the house mixer and you dont have to figure it out on the spot the night of the gig and for each different venue. You arent so dependent on their sound man (if they even have one) to figure it out.

I use an old Fishman Platinum Pro EQ preamp (impedance of 10mohm).

I dial down the trebles and highest mids almost completely and the bass significantly. Maybe if the impedence were one instead of 10 the EQ settings wouldn't be so drastic, I don't know. But what I get with the EQ/preamp sounds good and mellow the way I like it.

Also I have the added advantage of having the mandolins volume knob at my feet. Once the band really kicks in after sound check I often need to reach down and roll the volume up just to be heard in the mix. If I didnt have that, I would be screwed. Even when we do get a soundman at a venue, most of the time when you need an adjustment and look for him, he is gone. Few actually stay at the board and tweak things all night.

[pops1]

I use a Redeye and very rarely have to do anything with EQ, it has the 1 meg ohm input.

[capohk]

I wouldn't use a SBT type pickup without a pre-amp. They don't sound as good. That said, K&K pickups sound good by most people's standards when they are working properly. JJB pickups are essentially the same design, and also sound good when properly installed and functional.

If the pickup sounds terrible, it would suggest as others have stated that there is a problem somewhere in the signal chain. If you have eliminated cables and boxes, I would find a dental mirror or a small inspection mirror and have a look inside at the pickup itself. The two piezo discs should be super-glued underneath or just forward of the ends of the bridge feet. Sometimes double sided tape is used and this can become less than attached. As your mando is an oval hole, it should be reasonably easy to see if it is installed properly. It's easy enough to check the connections at the endpin jack too, in case you've got some funky solder joints or a grounding issue.


On the impedance issue, there seems to be equal weight of opinion on either side of the "whether it matters" debate. I generally like the tone from my Red-Eye in any setup, I struggle sometimes to find a good sound out of my Baggs Venue on it's own in the same situations so if I'm going into house PA or an amp with EQ, I'll use the Red-Eye, and if I'm straight into a powered speaker, then I use the Venue and run my Boss TU2 ahead of it to give the Venue 1meg input. This has been pretty successful for me. The buffer in the Boss pedal does the impedance matching and seems to help dial out the fake zingy sound I sometimes get.

Hope that helps, best of luck

Matt

[varmonter]

Plus one on the transducer inspection.the bass side transducer could be just dangling..

Also if your looking at high end di boxes the kk pure
Xlr preamp is also a di and is affordable in comparison to say a countryman di..plus you get
3 bands of eq at your fingertips and 1 mohm II.

[Folkmusician.com]

What color is the strap button on the endpin jack?

Do you know the year of the mandolin?

I ask, because K&K pickups are relatively new with Eastman. In the past they had Reso-Coil. And previous to 2012, they had no factory installed pickup.
Also is this a sunburst version of the 614? Some of these went to dealers with no pickups installed (I received a couple last year).

So we have earliest models, no pickup
Then Reso-Coil with an XLR out
Then Reso-Coil with a 1/4 endpin jack
Finally K&K that uses the Fishman SwitchJack

And then a few more random mandolins with no pickups at all thrown in for good measure.

Just wanted to be sure what we are dealing with here.

[almeriastrings]

I wouldn't use a SBT type pickup without a pre-amp.

You cannot physically use one without a preamp. Try it. Plug it straight into a power amp, for example...

The issue is where the preamp is in the signal chain. On thing it is generally worth avoiding is 'stacking' preamps, i.e. two high gain preamps in series.

A preamp does not have to be an external box. In many cases they are built into the mixer, or into an acoustic amp. The main thing is to get a suitable impedance AND level match.

Robert raises some interesting points... definitely worth being 100% certain what is in this mandolin (and checking the install). In one case I had a bad sounding pair of transducers, and the cause was they were wired out-of-phase, i.e., were cancelling each other partly out.

[eelcobeckers]

What color is the strap button on the endpin jack?

Do you know the year of the mandolin?

I ask, because K&K pickups are relatively new with Eastman. In the past they had Reso-Coil. And previous to 2012, they had no factory installed pickup.
Also is this a sunburst version of the 614? Some of these went to dealers with no pickups installed (I received a couple last year).

So we have earliest models, no pickup
Then Reso-Coil with an XLR out
Then Reso-Coil with a 1/4 endpin jack
Finally K&K that uses the Fishman SwitchJack

And then a few more random mandolins with no pickups at all thrown in for good measure.

Just wanted to be sure what we are dealing with here.

Hi robert, the mandolin is not sunburst, and has a blue endpin jack .the serial number is 10746374 will look up year of manufacture shortly. Does the colour of the endpin tell you what pickup is installed?

[Folkmusician.com]

OK, part of the puzzle solved!

The Blue Endpin Jack is the later Schertler Reso-Coil install (after they switched from XLR). That pickup operates at a mic level and can be ran directly into a good mic preamp. It will still work with a acoustic preamp as well.

So basically, your mandolin has a mic in it, not a piezo.

This will lend itself to a fuller tone, which will need more drastic EQ to clean up and keep from being muddy. It needs to be attacked with parametric EQ.

I looked up your direct box, and at first thought it would be perfect, but I see that it it is an unbalanced XLR input). So this somewhat complicates things. It doesn't look like this is really meant for mics. You want to be running the mandolin into a mic level input. I would suggest dropping a mirror in the mandolins and trying to identify how the jack is wired. Reso-coils are balanced pickups, and if the jack is wired that way, it would be best to run balanced right into the mic input on the mixer.

Without studying it, I am not sure how your direct box handles the 1/4" input. It may be fine to run it that way, maybe not. At any rate, neither input is balanced. Not a deal breaker in itself, but not ideal either. Balanced or not, it still needs to be a mic level input.

Which mixer are you using? Ideally, you will have a few bands of of parametric EQ to shape the tone.

I know this is starting to get confusing (and it really is).

1. despite, the 1/4 jack, just keep in mind, that this is a mic in your mandolin.
2. The pickup should be balanced, but may or may not be wired that way to the jack.
3. Assuming it is wired correctly to a stereo endpin, it is simply a matter of getting a balanced cable that goes from 1/4" stereo to XLR, and plugging it directly into the mic input on the mixer.
4. Play with the EQ until you get a tone you are happy with.

[almeriastrings]

I am familiar with that DI. Bad match all round for the Resocoil.

Explains a lot....yes, a 1/4" TRS balanced jack to XLR straight into the mic input XLR of your console should do it. The Schertler documentation on these is clear as mud, but it ought to be balanced on the jack....

[Cheryl Watson]

I had passive K&Ks installed in a high end mandolin and my high end OM Martin. The K&K sounds fabulous with my mandolin. I run it through either a Tone Bone (single channel model) preamp or a single Fire Eye Red Eye preamp. The Red Eye is more transparent by a good margin.

However, my Martin plugged in (it sounds GREAT acoustically) sounds TERRIBLE. Not only is the tone brittle and not transparent or acoustic sounding, it makes my own acoustic speakers and the church's speakers where I play buzz/sizzle. Turning the bass all the way off, reduces the buzz somewhat, but it sounds even worse. I've tried it without a preamp, with the Tone Bone, the Red Eye, with a parametric equalizer, a very detailed graphic equalizer, and a high end DI box, and nothing made the sound better. I ended up having go go back to a mic for a nice warm, clean acoustic sound, but then the mic is prone to feedback at higher volume levels, of course. The one place where it sounds OK, is through a friend's BOSE system (no preamp) with the right setting (Martin D28) on the board that is offered with the BOSE. One friend who used to do professional stage sound all over the world, said that something is wrong in the signal chain. But, then why does my mandolin sound so great and my guitar so lousy when I use the exact same setup? I am so confused.

I had the luthier who installed both K&Ks check out my guitar pickup to see what might be wrong. He could find nothing wrong with the installation or the wiring. He tried it again through his amp and it did not buzz/ sizzle, but it still sounds brittle. I'm about to pull my hair out, but instead, I think I will have that pickup taken out of that guitar. I probably should call K&K.

So anyway, just so you know that you are not the only player going through this. It's just that it's my guitar that is the problem with the K&K, not my mandolin. So perhaps either you need to buy a Fire Eye Red Eye (I use the balanced XLR out) or another good preamp or, there is something wrong with the installation or it is a defective pickup.

[Groundcoat]

Cheryl, I have K&K pickups in both my mandolin and guitar and both sound great without the need of any kind of preamp or fancy EQ. I strongly suggest you give their technical service department a call. I had a slight problem with my mandolin and they resolved the problem perfectly. They are very easy to deal with. Call them before you spend any money on a preamp or a mic or whatever. Don't pull your hair out, getting the right sound is just a process. Just think of all of the neat things you'll learn along the way.

[Folkmusician.com]

The Schertler documentation on these is clear as mud, but it ought to be balanced on the jack....

Exactly my thoughts after checking their website!

[eelcobeckers]

OK, part of the puzzle solved!

The Blue Endpin Jack is the later Schertler Reso-Coil install (after they switched from XLR). That pickup operates at a mic level and can be ran directly into a good mic preamp. It will still work with a acoustic preamp as well.

So basically, your mandolin has a mic in it, not a piezo.

This will lend itself to a fuller tone, which will need more drastic EQ to clean up and keep from being muddy. It needs to be attacked with parametric EQ.

I looked up your direct box, and at first thought it would be perfect, but I see that it it is an unbalanced XLR input). So this somewhat complicates things. It doesn't look like this is really meant for mics. You want to be running the mandolin into a mic level input. I would suggest dropping a mirror in the mandolins and trying to identify how the jack is wired. Reso-coils are balanced pickups, and if the jack is wired that way, it would be best to run balanced right into the mic input on the mixer.

Without studying it, I am not sure how your direct box handles the 1/4" input. It may be fine to run it that way, maybe not. At any rate, neither input is balanced. Not a deal breaker in itself, but not ideal either. Balanced or not, it still needs to be a mic level input.

Which mixer are you using? Ideally, you will have a few bands of of parametric EQ to shape the tone.

I know this is starting to get confusing (and it really is).

1. despite, the 1/4 jack, just keep in mind, that this is a mic in your mandolin.
2. The pickup should be balanced, but may or may not be wired that way to the jack.
3. Assuming it is wired correctly to a stereo endpin, it is simply a matter of getting a balanced cable that goes from 1/4" stereo to XLR, and plugging it directly into the mic input on the mixer.
4. Play with the EQ until you get a tone you are happy with.

Hii robert you are a wealth of information!! I'm beginning to understand why the problem is there. To answer your question i use the mackie DL16 digital desk which has fantastic parametric eq. I have a focusrite mic preamp in my little home studio do you think its worth trying that with the mandolin? Thanks again for all the help

[Folkmusician.com]

The Focusrite Preamp should work great! Just a question of whether or not you want to drag it to gigs. I would absolutely test it out at home though.

It looks like your mixer has 4 bands of parametric per channel. Perfect! The Focusrite Preamp should blow away the Mackie Onxy preamps, but you should do just fine direct into the Mackie.

Now.... We are still not 100% how your jack is wired or even exactly what is in your mandolin. I am not sure, but Schertler may have changed these at some point. The specs don't seem the same as I recall and there has been a change in price (lower now).

[Folkmusician.com]

OK, I found some old specs and they are what I recall (1500ohms and balanced)

Old Specs:
TECHNICAL SPECIFICATIONS

mechanical decoupling butterworth 2nd order, Q=0.6
nominal impedance 1500 ohm / 1000 Hz
frequency response 80 Hz to 14 kHz (+/-3dB)
equivalent output noise 139dB - 145dB typical
sensitivity 20mV/g
sensitivity (on instrument) ca. -28dBu
tmperature range -20¡C to +70¡C
contacts all hard gold 0.5um plated
connection XLR balanced or 1/4" jack on request
cable length 0.26m or other lengths on request

RESOCOIL is designed for musicians who need an internal solution fixed
inside the instrumentÕs sound box.

This sensor delivers the warm natural sound typically found in SchertlerÕs
DYN family of external contact microphones, with the added convenience of
a permanent installation that leaves no visible holes on the instrument.

RESOCOIL is suitable for use with classical type guitars, mandolin family
instruments, ukulele and resonator guitars.
----------------


Currently on the website, they are listing 380ohms, but they still list the Banjo version at 1500ohms. Not sure if this was a mistake, or it really is 380ohms now. Their warning: "Connection in to a high impedance input may cause volume/signal loss" leads me to believe, that could be a mistake.


New:
Nominal impedance 380 ohm @ 1 KHz
Frequency Response 40 Hz to 12 kHz (+/- 3 dB)
Dynamic range 139 dB, 145 dB typical
Sensitivity (on instrument) ca. -25 dB
Sensitivity (theoretical) 20 mV/g
Mechanical decoupling Butterworth 2nd order
Equivalent output noise 16 dB/0 dB = 0.002%
Contacts All hard gold plated 0.5 mm
Connection
XLR balanced
Jack unbalanced
Connection in to a high impedance input
may cause volume/signal loss

[eelcobeckers]

Yes i saw the specs on the schertler website, it was interesting to read that connection to a high impedance unit could result in loss of volume/signal. I have two gigs this weekend so i'll try 1. Through a mic preamp 2. Direct into desk and 3. With a passive DI to see how the tone changes. There's hope yet! Thanks everyone ��

[almeriastrings]

You should be fine into your Mackie DL preamps. Honestly, for live use there is almost nothing in it between the preamps in that and the Focusrite. The Onyx pres are pretty decent.

The lack of info on how these are wired on the Schertler site is disappointing. They need to address this.

Try first with a standard TRS to male XLR cable. If that works - fine.

If not, try an unbalanced jack to XLR.

MAKE SURE +48V IS OFF.

[eelcobeckers]

hi almeriastrings, quick question, you mentioned to make sure 48V phantom power is off? We use several DI's and condenser mics that depend on 48V to keep them going. will it damage or afffect the Scherlter pickup? What if i put it through a passive Di first? or is there another way around it? many thanks!

[almeriastrings]

hi almeriastrings, quick question, you mentioned to make sure 48V phantom power is off? We use several DI's and condenser mics that depend on 48V to keep them going. will it damage or afffect the Scherlter pickup? What if i put it through a passive Di first? or is there another way around it? many thanks!

If the Schertler is balanced via xlr, normally, they would be fine with phantom on.... however phantom power and a TRS jack is a bad combination as you can get 'shorting' and unbalanced application across the jack terminals. If it is unbalanced, then applying phantom power can destroy the pickup, the preamp, or both....

A transformer isolator should help. This another area where the manufacturers website is seriously deficient. The situation with phantom needs to be spelled out clearly. It isn't.

[fidlplr1979]

Piezo type pickups are very high impedance so to go through a passive DI and into the PA will result in very low quality sound, You require a high Z input preamp such as the Para-DI to make the impedances match. Good preamps do much more than amplify. I use K&K in both of the mandolins I use in the country band I play in and really like them.
Dave

This is the problem. It's a matter of impedance matching. Its also the nature of these surface-mount pickups like the K and K and the Shertler (which my 615 has) that they are going to pick up a lot of lower-mids in the frequency spectrum. The Shertler is actually a dynamic mic (which I prefer) and I don't use a DI at all just a Fishman PreQ. These are only about 100$ and they work great for boosting the signal at the same time as letting you do some EQ. But I go directly into a low-z 1/4" input on my PA.

[fidlplr1979]

hi almeriastrings, quick question, you mentioned to make sure 48V phantom power is off? We use several DI's and condenser mics that depend on 48V to keep them going. will it damage or afffect the Scherlter pickup? What if i put it through a passive Di first? or is there another way around it? many thanks!

Anything put in between the signal chain from the phantom-power source such as a DI or preamp(especially a 48v powered one) will protect the pickup from the 48v. I have a Shertler on my 615 and I have used phantom pwr with no problems but to be safe like Algeria said I'd avoid direct phantom power to your mandolin pickup. I usually go with a Fishman PreQ II in the signal chain (which requires power) and allows me to EQ out some of those mids. Notice I said EQ (out), it's much better to take out offending frequencies than to add the ones that are missing, so instead of adding treble exclusively when you EQ try pulling out from 500-1.2khz and cut everything below about 250hz. Remember high-pass everything. if you can

[eelcobeckers]

I have a gig tonight, so the plan is to try a few different setups. I'll start with a K&K preamp i borrowed, then try a little ART mic preamp, and finally direct into the desk with 1/4 inch jack. Will post results tomorrow! Wish me luck!

[eelcobeckers]

Anything put in between the signal chain from the phantom-power source such as a DI or preamp(especially a 48v powered one) will protect the pickup from the 48v. I have a Shertler on my 615 and I have used phantom pwr with no problems but to be safe like Algeria said I'd avoid direct phantom power to your mandolin pickup. I usually go with a Fishman PreQ II in the signal chain (which requires power) and allows me to EQ out some of those mids. Notice I said EQ (out), it's much better to take out offending frequencies than to add the ones that are missing, so instead of adding treble exclusively when you EQ try pulling out from 500-1.2khz and cut everything below about 250hz. Remember high-pass everything. if you can

Thanks for the tips regarding which EQ to notch out and to use HP filters. Looking forward to trying them out tonight!