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- - K&K: WWTT ?!? (https://www.acousticguitarforum.com/forums/showthread.php?t=685134)

As in, What Were They Thinking? For the K&K Sound Pure XLR preamp, no 9V adapter jack? Only power source is phantom or battery?

I hadn't used my Martin with a K&K on a gig in years due to the undefined and mushy sound. "Natural"? Sure, just not useful in a stage setting. Bought a used K&K XLR preamp, makes all the difference in the world, much more focused. Love the phase switch.

One caveat: the K&K pre runs 9V, either via battery or phantom. If you're running this always-on pre on battery you have to monitor the battery status fairly regularly or risk low voltage distortion. They could have made changing the battery harder but not really - there's two very tiny screws that hold the top on, they just beg to get lost when changing. I'm just gonna tape them on the chassis somewhere in case I sell it someday, and use tape to hold the top on.

And phantom? Unavailable unless of course your mixer/amp has it, and you go directly in bypassing any and all FX or volume pedals. Bad design. The pre is specific to the pickup and logic dictates it's first in the signal chain, not last. I'm not gonna give up my pedals (boost, multi-fx, looper etc) just to get phantom power.

Quote:

Originally Posted by negriljerry (Post 7450947)

I had a similar issue with the preamp/mixer that goes with the Trinity system. But I just used a 9v battery to 9v standard pedal size plug and filed a notch in the casing to allow the cable to pass. That way I could just run the mixer on my pedalboard and never worry about a battery again.

Quote:

Originally Posted by negriljerry (Post 7450947)

As in, What Were They Thinking? For the K&K Sound Pure XLR preamp, no 9V adapter jack? Only power source is phantom or battery?

Hi negriljerry
I've owned a slightly different version of your K&K Preamp (it's two channel for the dual source Pure mini plus internal mic). But similar designed housing.

Here's a really simple fix for the screws…

I just pulled the screws and tossed them in the junk drawer.

Pulled out a roll of painter tape and taped the sides shut…I renew it when it wears out.

That way I can get into the case in about 5 seconds and adjust tone, output gain and 'pot' adjustment tool (tool is velcroed to the inside of the case). And I can seal it up a few times before I need to change the tape.

K&K also labeled the knobs and jacks on the TOP of the 'box' without repeating them on the end , so I just wrote the names under jacks and knobs with a Sharpie…by the way that box design was in use more than 25 years back.

When I asked them back then about external power, there really wasn't the thought of adding a jack on it. If they had, K&K would have likely wired it such that we'd have to buy their charger…so I'm just as glad they didn't.

https://live.staticflickr.com/7227/6...8a8298a2b4.jpg

https://live.staticflickr.com/7087/6...3280f93675.jpg

https://live.staticflickr.com/5332/6...99839d1913.jpg

https://live.staticflickr.com/8199/8...8a79aa7409.jpg

Mine's so old their labels all fell off, so I'm glad I wrote them onto the case.

They are capable and quiet preamps. Just not a ton of features or output options.

So I carry a passive direct box to run from guitar-->pre-->DI box-->PA/Amp

I have a Power Pack, an older model that's like the Pure Preamp without the mid control. Mine lost its screw years ago and the top stays on the case just fine without it.
They're odd devices, the box feels flimsy and the components used are nothing fancy, but they're quiet and fairly astutely designed to work well with K&K's style of pickup. I actually traced the circuit of mine out of curiosity one day, because it sounds a little better than a simple buffer plus gain and I wondered why. It might be because there's a little low end roll-off voiced into the very first gain stage that cleans up some of the excess low end before it messes with the headroom of the circuit or anything downstream.

My Fire-Eye Red-Eye just has phantom and battery. Not a big deal. The battery is just backup for when the phantom power bugs out, which so far has been never. I've been using it for five or ten years, and the battery is still fresh because it's never drawn from. (I test it every two or three years.)

But you're right, it wouldn't hurt to have an AC adapter socket rather than a battery. I hate using batteries, too. I think the new Red-Eyes do have an adapter socket.

Here ya go..

Preamp Power Supply

Quote:

Originally Posted by wood nacho (Post 7451743)

Here ya go..

Preamp Power Supply

Hardly a bargain at $58 plus shipping.

Things like this are the reason I've always purchased mixers with phantom power - I also ALWAYS use condenser mics, so it make all of it easy:D

I own a K&K Mini preamp I've had for years. I never used the battery because, well, it's one more battery i have to deal with.

Anyway, used something like this for years. Works great. I don't use the preamp anymore but if I did, I'd plug it in.

https://www.amazon.com/9v-Battery-El...s%2C120&sr=8-6

Quote:

Originally Posted by Medford Guitar (Post 7451959)

Yep- this is similar to what I was trying to describe above.

Very cheap and easy fix if you want to mount anything to a board that is only battery powered.