[wilsonjm]

Here's my parts list...and...it comes to $78 for everything, which I think is really a lot for a cmoy amp. However, I should do this right the first time. So I'm willing to spend up to $100 to get the best sounding amp.


Radioshack 276-147 Grid-Style PC Board-2200 Holes $3.99
Radioshack 275-0624 SPST Micromini Toggle Switch $2.79
Radioshack 900-1446 5mm LED 2V With Holder-Green $1.45
Radioshack 274-852 Phono (RCA) Jack (2) $2.69
Radioshack 278-1215 UL Recognized Hookup Wire 22AWG $3.99
Radioshack 64-013 Silver Solder 62/36/2% 0.022" 1.5oz $3.99
Radioshack 273-1672 1.5-12VDC/300mA Regulated AC-To-DC Adapter $19.99
Digikey SC1107 1/4" Stereo Jack $1.96
Digikey OPA134PA-ND op-amp OPA134PA (2) $4.20
Digikey P10278-ND 1000 uF 25V electrolytic capacitor (2) $2.58
Digikey P3474-ND 0.47 uF 50V polypropylene capacitor (2) $3.78
Digikey 10.0KXBK 10Kohm 1/4W 1% Metal Film Resistor (5) $0.54
Digikey 4.75KXBK 4.7Kohm 1/4W 1% Metal Film Resistor (5) $0.54
Digikey 47.5XBK 47.5Kohm 1/4W 1% Metal Film Resistor (5) $0.54
Digikey 100KXBK 100Kohm 1/4W 1% Metal Film Resistor (5) $0.54
Digikey 1.00KXBK 1Kohm 1/4W 1% Metal Film Resistor, gain 11 (5) $0.54
Digikey AE7313 DIP-8 IC Socket, gold contacts (2) $1.08
Digikey CP-6-ND DC Power Jack $1.83
Digikey 226-2012-ND Gloss Al 0.925" Diameter 0.25" Shaft Vol. Knob $5.13
Digikey HM164-ND Hammond Enclosure 7x6x2" $13.35
Digikey P2U4103-ND Volume Control, Panasonic 10K $2.66
TOTAL: $78.16


I've ditched the batteries and gone to a Radioshack 12VDC 300mA regulated & filtered AC/DC adapter, since i am going to be using the amp several hours a day I don't want to deal with batteries.

I dont know if the Hammond enclosure (7x6x2) is large enough to include an internal power supply, and if so this might be too expensive and I would know nothing about the design needed for that internal PS.

how are the rest of the parts looking? Even though i'll spend $100 i of course want it to sound better than a $20 cmoy.

 

[erix]

It's a nice list but I'm wondering about a few things.

First, are you building a cmoy or a 47?
Next, is price or quality of the part the prime consideration?
After that, Why choosing only digikey and ratshack?
Furthermore, RCA jacks? Portable or not?

If price is a consideration I would peruse the Mouser catalog before going to the shack.

Generally, everything at Radio Shack is at least twice what you'd pay at Mouser. Granted, you have to pay Mouser to ship but you can use USPS priority (or 1st class) and get a decent amount of parts shipped for <$3

Penny Pinching: instead of buying 5 resistors to get the 2 you need, buy 2 RN55 1/8W Mil-Spec resistors from Mouser - much better part, cheaper too.

I realize Mouser doesn't have the B-B opamps (p.s. - why not a dual - makes no difference at this level and theres less chance of messing up if you use a dual) but TI has a great sample program.
I didn't just type that, did I?

If you want the best amp you can get for your $100 you should look into using either an 2426 rail splitter or a BUF634 for the virtual ground on your power supply - much more accurate. use the 2426 for a bone-stock cmoy, BUF634 everywhere else.

Tangent has an excellent tutorial on how to build one, with part numbers and suppliers.

I made this one and this one which show what you can do in a small space. Check them out before you order anything - you might decide you don't need stuff.

I think you could easily save money by avoiding RadioShack for all but the perf board - niether Digikey or Mouser has a low-cost version. They do have Veroboards which are much better and much$$

ok,
erix

 

[wilsonjm]

I have decided to build Apheared's CMOY #42 amp. This will be a challenge. Right now I am trying to come up with the schematic for it. I think I have it right (probably not lol) except for where to put the resistors and caps that are not included in the original Cmoy amp.