Okay, you read in the last post about how the easiest way to come up with a capacitor list is find someone who has done the job you are looking to do and get them to give you their list. And then I talked about how I made a list, but I didn’t post it. Well, by popular demand, here is my Korg 800DV capacitor list. I will give you the board by board list, the specification changes I made to try and buy in bulk and the final list I ordered from Mouser.
SBC-049 has the following original capacitors – all are radial (both leads out of same end):
- 1x .47uf 16v Tantalum
- 1x 2.2uf 16v Tantalum
- 2x 10uf 16v Tantalum
- 7x 1uf 50v Electrolytic
- 2x 10uf 16v Electrolytic
- 6x 10uf 25v Electrolytic
This is the list I will be ordering after upping a few voltages and replacing tantalums with electrolytics. Tantalum capacitors have a neat trick they do where they suddenly die and become a dead shot ie a piece of wire, This isn’t ideal. The list:
- 1x .47uf 16v
- 7x 1uf 50v
- 1x 2.2uf 16v
- 10x 10uf 25v
SBC-50 has the following original capacitors -again, all are radial.
- 1x .33uf 16v Tantalum
- 1x .47uf 16v Tantalum
- 2x 10uf 16v Tantalum
- 4x 10uf 25v Electrolytic
- 3x 220uf 25v Electrolytic
This is the list I will be ordering after upping a few voltages and replacing tantalums with electrolytics and multiplying everything by 2 since there are 2 of these boards:
- 2x .33uf 16v
- 2x .47uf 16v
- 12x 10uf 25v
- 6x 220uf 25v
SBC-51 has the following original capacitors -again, all are radial.
- 3x 3.3uf 16v Tantalum
- 1x 1uf 16v Tantalum
- 7x 10uf 25v Electrolytic
- 5x 33uf 16v Electrolytic
- 1x 100uf 25v Electrolytic
This is the list I will be ordering after upping a few voltages and replacing tantalums with electrolytics and multiplying everything by 2 since there are 2 of these board. Note that I upped the voltage for the 1uf to 50v. I have these on hand and this is not a problematic voltage jump:
- 6x 3.3uf 16v
- 2x 1uf 50v
- 14x 10uf 25v
- 10x 33uf 16v
- 2x 100uf 25v
The power supply has the following original capacitors. All are electrolytic.
- 1x 1uf 50v
- 1x 100uf 16v
- 1x 220uf 16v
- 1x 220uf 25v
- 1x 470uf 25v Axial
- 2x 470uf 50v Axial
This is the list I will be ordering after upping a few voltages:
- 1x 1uf 50v
- 1x 100uf 25v
- 2x 220uf 25v
- 3x 470uf 50v
Now I do a big combined list from all the boards. 82 caps! But wait, there are more. One of the oscillator boards had a 2.2uf 16v tantalum capacitor on the back between two traces, and there are 2x 1uf 16v and 2x 10uf 25v tantalum capacitors between some of the sliders and switches on the control panel. Below is the final final – 87 capacitors. Only the 470uf axials will cost you more than maybe 25 cents each.
- 2x .33uf 16v
- 3x .47uf 16v
- 2x 2.2uf 16v
- 6x 3.3uf 16v
- 12x 1uf 50v
- 38x 10uf 25v
- 10x 33uf 16v
- 3x 100uf 25v
- 8x 220uf 25v
- 3x 470uf 50v
Now that we have that out of the way you may be asking yourself – why did they use two 470uf 50v caps and a single 470uf 25v cap? In general back when the Maxi-Korg was new, the more capacitance and higher voltage meant a bigger, heavier and more expensive cap. The smaller capacitor minimized shipped weight, board size and capacitor cost which maximized profit. Multiply that across the tens of thousands of products Korg made and you have some real money.
Today I don’t care because we are talking about maybe a $10 difference between the 87 capacitors and their impact on cost factors, and I plan to hang on to this one for a while, but in the 1970s competition among synthesizer builders was fierce.
Up next: probably tackling some of the sliders and pots on the control panel.
Preserve the Sound 