What cheap-0 parts do you reccomend? (Or could you sell me some?)

[gmilitano]

Here you go,

No hard data but sounds as if they've doine their homework...


here

Carbon Films are one step up from CC's... about the worst...

Great article. Exactly what I was looking for....Thanks.

Some good tips about using larger resistors to cut back on noise. I had thought about the fact that most pots are carbon. Good tip to use higher wattage and lower R pots with the nod clearly going to conductive plastic. I did not know that wirewounds were the best! I agree that distorsion caused by carbon is more pleasing. That is likely why carbon is the choice for tube gear.

Cheers,
Gio.

 

[rossl]

Re: Re: Re: Resistors for Chip Amp

Metal film resitors are essentially a thin, long wire. Thus they have inductance. I would have guessed that this would make them a poor choice for audio. However, it seems almost all Chip Amps are built with metal films?

precision thin film 0805 resistors aren't a long wire and are not high inductance.

http://dkc3.digikey.com/PDF/T061/1221.pdf

I know some of you guys won't consider using surface mount, but I don't mind paying 14 cents for a .1W, 0.5% low noise resistor.

The resistor is a small square of Ni-Cr alloy. There is a small inductance in the leads but this is much less than any standard leaded resistor.

Too bad it won't work in the kit mentioned at the start of the thread. When I make my own PCB I use these Susumu.

 

[jackinnj]

Re: Re: Re: Re: Resistors for Chip Amp

precision thin film 0805 resistors aren't a long wire and are not high inductance.

I buy the "end of run" reels of SMT parts on EBay -- the sellers are usually contract manufacturers -- they provide the exact part number -- you've got to be patient to wait and see when they come up for sale.

SMT devices are "de rigeur" (well not quite, but you get my meaning) when you are working with current feedback opamps.

 

[rossl]

Re: Re: Re: Re: Re: Resistors for Chip Amp

I buy the "end of run" reels of SMT parts on EBay -- the sellers are usually contract manufacturers -- they provide the exact part number -- you've got to be patient to wait and see when they come up for sale.

SMT devices are "de rigeur" (well not quite, but you get my meaning) when you are working with current feedback opamps.

Thanks for the tip but usually 10 or 20 resistors of any one value is all I need at a time (grin)

I should also point out to anyone considering surface mount, there is a huge difference between 0603 and 0805. With 0805 you can easily solder the resistor by holding one end with tweezers and tacking the other end with the soldering iron. A 0603 is small enough that it is hard to hold with tweezers and also keep the tweezers out of the solder. Stick with 0805 or larger!

I use some 0603 ceramic decoupling caps for really low inductance but they are a big pain to hand solder.

 

[jackinnj]

Re: Re: Re: Re: Re: Re: Resistors for Chip Amp

Thanks for the tip but usually 10 or 20 resistors of any one value is all I need at a time (grin)

I should also point out to anyone considering surface mount, there is a huge difference between 0603 and 0805. With 0805 you can easily solder the resistor by holding one end with tweezers and tacking the other end with the soldering iron. A 0603 is small enough that it is hard to hold with tweezers and also keep the tweezers out of the solder. Stick with 0805 or larger!

I use some 0603 ceramic decoupling caps for really low inductance but they are a big pain to hand solder.

I use 0603's (sometimes) -- but in my sensecence I prefer 0805's, 1206's 1210's --

here's a hint -- you can purchase Kester solder paste from DK and elsewhere -- you almost need a pin to apply it -- I set a tiny bit onto the pad and use extremely fine tweezers (they are from Italy) to place the parts. then cook it in a toaster oven (which is dedicated solely for this purpose.) i have yet to modify the oven for the precise heating and cooling times, but haven't yet scorched an IC or other SmT component.

 

[Spasticteapot]

I've been digging through Mouser, and I can't find any 2.7 ohm 2 watt resistors for the Zobel. Same with Digikey. Could I get away with paralelling 10 27ohm resistors, or would this kill sound quality.

Also, could anyone reccomend a particular brand?

 

[jackinnj]

DK has 2.7, 2W in several flavors -- Yaego, BC Components and Phoenix Components.

 

[rossl]

I've been digging through Mouser, and I can't find any 2.7 ohm 2 watt resistors for the Zobel. Same with Digikey. Could I get away with paralelling 10 27ohm resistors, or would this kill sound quality.

Also, could anyone reccomend a particular brand?

Digikey:
Yageo, 2.7W-2-ND
Panasonic, P2.7W-2BK-ND

both are in stock.
Panasonic is a little smaller.
Yageo claims to be non-inductive and is cheaper.

 

[Spasticteapot]

Much thanks.

As long as I'm getting all the help (THANKS!), I do have one more question, and an odd one at that.

I've seen assorted kits for "line level meters" that provide a bar graph of the output from a source. Can you reccomend one, and tell me the best place to connect it? I don't want to affect audio quality, but I'll be darned if they don't look cool.