Mine cost me about $125 or so: five buffers, decent (but not overboard) caps and resistors, Cardas RCA jacks, the opamps with adaptors that Tangent sells. If you want to be really precise about how much it'd cost you, add the parts in Digikey and Mouser to an order and see what the total is -- doesn't mean you have to buy them, of course.
Top Mall-Fi poster. The T in META42. Formerly with Tangentsoft Parts Store
Sep 27, 2001
The minimum is around $50-60, without using components I would consider too cheap to bother with. The upper limit is your own willingness to spend money. Seriously, you could spend many hundreds on it. Whether that would be a good idea or not is something you'll have to decide for yourself.
Mine cost something between 75$-100$. I haven't counted exactly how much... Doesn't look too good because I've been cheap on parts unrelated to sound (case, LED, knob, switches...).
So, basically it really depends on what you want. For example, you can get a 100$ custom made metal case or simply recycle some kind of box you already have that cost you nothing. Use a battery pack instead of a 200$ linear power suppply... These are places where you have a lot of options without making concession on sound quality. It really depends on how much you are willing to spend on these one. Evidently, an amp working with 12-AA cell in a shoebox will not look as good as a brush metal case with LED and a power supply...
You may go with the minimum number of buffers (3). That way you save some money with minimal loss on sound quality.
You may also choose the opamps according to your budget. If you look on Tangent's parts list, you have different choice there. Going for three OPA627 will cost you much more than OPA2134/OPA134. But here, you will have to make some concessions on sound quality.
Just take the Tangent's part list and read the descritions. You could then see which part has an influence on sound quality and which one doesn't. Then put your money on the parts that influence sound quality and cut the others. That way you will end up with a good sounding (although not very good looking) amp at minimal cost.