Seventh Circle Audio

I received my J99 kit version 3.2 but the BOM and the schematic do not match, nor do the assembly instructions.

The picture with the mil max pins looks different. Do you push them through the top and solder them on the back? Assembly instructions do not specify where they go and since the picture doesn't match my kit it's a bit confusing. Holes up? I'm assuming they will hold the 990 op amps.

I received 2 zero ohm resistors not listed anywhere and I'm assuming those go in place of the load isolators. (Wish I would have gotten a couple of those with my C84 kit.)

On the BOM U1 and U2 are listed as AD797 but none came with the kit and I'm assuming the 990s go in their place.

My kit was missing 11 resistors which may have been due to the out of date BOM.

Any idea when there will be updated insructions etc.?

On Rev 3.2, the parts below are optional and are not included. Simply leave them unpopulated. The circuit is otherwise unchanged.

C21, C22, C28-C31
R27, R39, R41-R50
U8, U9

You should have 2x 150R resistors (R36 and R40) and 2x 100uF/63V capacitors (C7 and C23).

Thanks for the reply Tim. Can you answer the other stuff?

Mil max pins

zero ohm resistors

AD797 in the BOM

updated schematic and assembly instructions

The Mil Max pins are pressed through from the top. The little ridges on the edges catch on the fiberglass of the board, so it takes a bit of pressure to push them all the way in (I have a small philips head screwdriver that I used to push them through.) They will end up flush to the component side of the board when all the way in (and will stick a fair bit out the back.)

zero ohm resistors

Use these in place of L1 and L2, or just use a piece of wire.

AD797 in the BOM

U1 and U2 can be any of a variety of op-amps. The new boards (3.2 and later) will directly accept ICs (like the AD797) or discrete op-amps (like the JH990C).

updated schematic and assembly instructions

Updated instructions will be up in a few weeks, but the existing schematics and instructions still apply. None of the old part numbers have changed, but a few have been added.