NEW!!! SC-1 Mic Preamp Kit
Status: Under Development:

UPDATE

Revision 4 PCB

Yup. Sorry guys... Rev3 is currently on a Fedex truck on the way here. If the planets are aligned right, I'll receive them tomorrow... otherwise I'll get it Monday.

But Revision 4 PCB is currently on my computer screen right now. This could put another delay to bringing this to production by a week or two.

But first let me explain why I decided to do a Revision 4. It adds several enhancements to make this preamp even better.

1. Slow-start phantom power - i.e. 48V isn't applied suddenly, but ramps up slowly. (high end preamps have this feature, so I think mine should have it too! ) This should also lessen the popping sound when you turn on phantom power, or if you accidentally turned on phantom power, you can quickly turn it off again.

2. Reduced/Eliminated clicking/popping when changing gain settings at the higher gain - Added some changes to the gain selector stage after corresponding with a THAT Corp. engineer. This is to lessen/reduce/eliminate popping sound when you change gain settings using the selector switch (popping sound most prominent at the higher gain settings (54/60/66/72). Again, this is NOT a *must* update, but it certainly makes for a more *refined* user experience. The possibility of using a "shorting" selector switch was also discussed, and I talked with a Grayhill rep about it's availability. Good News! There is a corresponding part number! Bad News! It's custom order, and will take a few weeks of lead time.

3. Use of EXTERNAL, 3rd-PARTY compressors/signal processors with the SC-1 via INSERT jacks - Somebody brought up the idea of using a real INSERT jack to interface the SC-1 preamp with an external compressor unit or signal processor. That way, you can connect your RNC or whatever compressor using INSERT cables to the SC-1. I had to add a resistor so *if* there is a short somewhere in the cable hooking it up to you external compressor, it wouldn't damage the preamp (because you're shorting it to ground). Again, this change was recommended by a THAT engineer... so there it goes.

4. Just minor cleanup in the PCB layout brought about by adding new components to the PCB.

So I hope you guys understand! I'm being transparent on what's going on behind the scenes. I hope you all don't get tired of waiting.

Let's put it this way... I am happy with the way Rev1. PCB is working. I think Rev4 will make it even better and a more refined product!

INSERT Feature

Found a 1/4" TRS jack with NC switches, wired them to the prototype preamp and tested it using standard INSERT cables. Hooked up an EQ unit, and mannn... it works!

Some pics.

The noise level does increase when you hookup a 3rd party unit via Inserts since now the signal has a longer route to travel, and also going out unbalanced, and coming back in unbalanced.

But definitely, the preamp can be fitted with INSERT jacks. The volume control of the SC-1 preamp also controls how much signal goes out to the INSERTed device.

Another photo:

Connecting an RNC to the SC-1 preamp via Insert cables.