Mandolin > K&K Twin Internal > Grace Bix - Help please

So I finally pulled the trigger on a Grace Bix (good enough for Jarrod Walker, right?...). I have a K&K Twin installed in my mandolin. I've tried various preamps/pedals, LR Baggs Para DI, Boss AD-10, Red-Eye, all to varying degrees of success. Lately I run direct more often than not. I do like to add light effects (delay, reverb). I also play electric guitar at church and sometimes mandolin where I use a Line 6 Helix. Another plus for the Bix is its FX Loop where I'll probably run a Line 6 HX Stomp for effects.

I'd love to hear from anyone using this or a similar setup. I'm open to your ideas.

The first question I have is about input impedance. K&K lists the mandolin pickup impedance as "High ohmic". The Bix manual says its input is 10Mohm and mentions some K&K pickups requiring lower input impedance and suggests wiring a special cable to bring the instrument input impedance to 1Mohm. Can anyone tell me if this wiring scheme is required for the mandolin twin?

Thanks for your time and response.
Ron

Electronics works with a factor of 10 so 1 meg to 10 meg will work, but the mandolin twin is 1 meg and you will get better sound at 1 meg than if you go into 10 megs.

If I recall correctly you’ll get more noise at the 10mOhm then the one, but both work. I have a Felix and it is switchable and there isn’t much difference between the 2 except body noise and feedback at high levels.

Make sure all of your effects are in the loop if you are using the xlr out. Pedals before the preamp don’t seem to work as well with piezo pickups. I know that doesn’t fit with the standard dogma but have tried it many different ways and that’s my experience, YMMV.

A good piece of advice I got here was don’t use the EQ to boost, just cuts. Does the Bix even have a midrange knob? Reasonable to leave off, let your natural sound come through and cut what you don’t want. Then you can get the most out of an appropriately set gain. But don’t just crank the bass and the treble to zero, there are some sounds that let you sound natural there, attenuating them is desirable though.

The placement of your piezo makes a big difference. And what it is attached to the top with. Not that you can exactly adjust that now, but just know it makes all mandolins sound a little different and have different characteristics. One mando I have feeds back on a D note more then the others, with the piezo placed by the same luthier. Just good to know.

I’ve had a Venue DI, a Radial tonebone, an Alix and a Felix, but I mostly use the Tonedexter these days. It just sounds the best to me. It did take like 20 different tone maps and 3-4 different mic trials to get the one that I use all the time now, but the impulse mapping to a mic sound is pretty natural compared to the regular preamp. And it is specific to your piezo output. Which I suspect is why it works so well, but I am getting off topic.

I feel like live sound is a skill you have to develop over time. I am much better then I once was but am always learning. Trial and error and making mistakes and learning from them is what makes you better.

Pedals generally don't work well with passive pickups, UST or soundboard transducer, in my experience (I used to do some live recordings), so use the FX loop for all of that stuff, which should be better aligned for input/output from a "guitar pickup" signal. Even a tuner pedal use, to me, suggests getting a preamp that has FX send/return capability. (I kept a Dee-Eye in the bag for use in cases where whatever was hooked up wouldn't work well.)

Thanks everyone! I'm still a little unclear on 1M vs 10M ohm going from the K&K to the Bix. Not sure what "high ohmic" means on the K&K? I just want to be sure I match the K&K impedance with the Bix. Pardon my hard head on understanding this...lol

I will be using the Bix as a DI out and running FX in the loop of the Bix. This part I do understand but certainly appreciate the feedback.

Thanks "dang" on the EQ suggestions. One of the gripes I read about the Bix is it not having a midrange control but I understand some adjustments can be made using the High/Low and Gain controls. We'll see.

Got a few days before the Bix arrives but ready to give it a try!

Try running straight into your Helix. Use the Mic Pre, along with an EQ block, and a compressor (LA Comp is my favorite). From there you can add whatever effects you like. I usually use the spring reverb.

I've had (and still have) a lot of different DI's, but these days I only use 1... an HX stomp.

If you get the preset right, in my opinion it'll sound as good or better than anything else.

I use mine with Mandolin, Acoustic guitar, Electric guitar, and Bass. I think it sounds great for all of them. Give it a try! They are incredibly versatile.

Looks like ohmic = “of or relating to a circuit element, the electrical resistance of which obeys Ohm's law”
High impedance is relative to the low impedance of an electric guitar pickup.
The 10 Mohm is often for a bass or a piezo that is giving a somewhat smaller signal.
A mandolin with the KandK with twin heads can give a touch more signal then the average piezo…
I think KandK is just saying it follows high resistance…
I would ignore the 1 vs 10 Mohm and give it a try, use the cable as described for the bix if you are having “excessive low end or feedback issues”

Quote:

---

Originally Posted by JFMando

Try running straight into your Helix. Use the Mic Pre, along with an EQ block, and a compressor (LA Comp is my favorite). From there you can add whatever effects you like. I usually use the spring reverb.

I've had (and still have) a lot of different DI's, but these days I only use 1... an HX stomp.

---

Yes! This is exactly what I do with the Helix at church. I'm primarily on electric guitar but once a month or so I'll bring in the mandolin. I also use the Mic Pre, EQ with high and low cuts and the LA Comp. Then I add light delay and reverb as needed. I'm spoiled with an excellent sound tech at church who makes it sound great in the house. The one thing I do have issues with is balancing preset outputs between the mandolin and guitar, but again the tech helps me out greatly.

In our bluegrass group I am using the HX Stomp with the same settings, other than the mic pre. I'm hoping the Bix will help with EQ and give a better gain structure. And having the FX loop and boost functionality of the Bix will be helpful too. All this in a smaller footprint than the Helix.

Quote:

---

Originally Posted by dang

I would ignore the 1 vs 10 Mohm and give it a try, use the cable as described for the bix if you are having “excessive low end or feedback issues”

---

Good advice! I will do that. Thanks!

I do not have the background on the tech aspects of the pickups and preamps. I do however have some experience with the k and k pickups. Both good and bad. The k and k in my loar 600 is ok. But it makes a difference what i plug into. Straight into my schertler amp its fine, sounds clean and full, but if you look at the top too quickly it picks it up and you hear the thump. Even though i am percussive in playing( i tap the top a lot) these pickups tend to over emphasize that thump. That same mandolin straight in to a PA, no pre or DI sounds thin. The best sound i got out of it is through a fishman tone DEQ. Not sure why, but i use that into a sound board into powered mains and the mandolin sounds close to natural. It still has the thump, but that pedal has a switch to lower the sub bass frequencies that get pushed through. The K and K preamp i have, uses a 9volt and has volume bass treble mids works ok, but does not make the instrument sound as natural. So the same mandolin with different amps/ preamps sounds different, and it was through trial and error that i finally got a sound i can deal with.

I had K and K in my Eastman ar610 archtop. They were poor at best. It didnt sound much like a guitar, and no EQ or preamp made a difference, so out they went, and in went a hand made Barberra Transducer. I have had the k an k in a few other instruments, as that is how they were shipped to me, but over all they seem a lot of work to get a natural sound, especially without that constant thump of the top when the wind blows or at spec of dust hits it.

I have a K&K into a RedEye. The sound is really nice, and I don't have any top noise. I have a finger rest/pickguard, and I have one piece we play that requires a percussive tap, the finger rest is not loud enough to make it work. I have to tap the bridge or top. So unless I am purposely trying to make noise it doesn't. I also play on a boat cruise where there is always air moving because of the boat moving, and sometimes a wind added to that, and have no problem with mine making noise.

Quote:

---

Originally Posted by Ron G

So I finally pulled the trigger on a Grace Bix (good enough for Jarrod Walker, right?...). I have a K&K Twin installed in my mandolin. I've tried various preamps/pedals, LR Baggs Para DI, Boss AD-10, Red-Eye, all to varying degrees of success. Lately I run direct more often than not. I do like to add light effects (delay, reverb). I also play electric guitar at church and sometimes mandolin where I use a Line 6 Helix. Another plus for the Bix is its FX Loop where I'll probably run a Line 6 HX Stomp for effects.

I'd love to hear from anyone using this or a similar setup. I'm open to your ideas.

Ron

---

Hi Ron, I don't know a lot about the electronics but I have one and the Baggs which is fine for playing in a bar, cafe or other noisy environmont but direct is much cleaner as is of course a good mic. YMMV

Hey there….

I have a K&K Pure Mini installed in my Martin and run it through the Pure pre-amp. It sounds great. Previously I had a B-Band and it was not for me.

For my mandolin, however, I have a Schertler DYN-M and run it through the Schertler Yellow pre-amp. It’s a whole different ball game than piezo pickups, truly. It drips with tone.

I don’t know why Schertler doesn’t catch on better in the U.S. I suspect it’s because it’s pricier, but for what you get it’s not too much more, and they have outstanding customer service. I had a problem with mine once and as part of the warranty they shipped me a new one the next day on the honor system. I mean if tone is king it’s worth it, right?

I used to use a Schertler years ago, but it fed back way too easily. A mic would have worked better. My K&K sounds very good, it's not a mic, but still sounds very good.

Yeah, it did that for me without the Yellow, but the Yellow reduces it drastically. Nonetheless, it has a setting to dry out the tone to varying degrees which practically eliminates any threat of it.