12v to 5v

[wwenze]

Originally Posted by audiogeekess

Thanks, does the LM78M05 come with those input/output caps or do I need to buy those? Looks like they are outside the chip, but N-Brock said it had a few extra parts.

Chris, what capacitor would I use with a 5v battery? The same one used with that LM78M05? .1 uF?

This is the power supply I have: http://www.amazon.com/Pyramid-PS3KX-.../dp/B0002JTD2K

I need 5v 500ma for the DAC.

The capacitors don't come with the LM7805. They are required, but the larger value ones (100-1000uF) may be omitted in a mod if the power supply is ripple-free and low-impedance and the device it's powering already has its own capacitors. Small values (.1uF) will still be required for stability, check the datasheet.

[ChrisA]

Originally Posted by audiogeekess

Thanks, does the LM78M05 come with those input/output caps or do I need to buy those? Looks like they are outside the chip, but N-Brock said it had a few extra parts.

Chris, what capacitor would I use with a 5v battery? The same one used with that LM78M05? .1 uF?

This is the power supply I have: Amazon.com: Pyramid PS3KX 3-Amp 12-Volt Power Supply: Car Electronics

I need 5v 500ma for the DAC.

The 7805 is a chip with three leads. Looks like an larger transistor. so no it does not come with other parts.

On a battery the value of the bypass cap hardly matters, small is good 0.1 or 0.01uf is fine.

You can buy a power supply PCB in ebay for about $5 Read the data sheet for the LM7805 and if you don't understand it buy the PCB. There are many on eBay, see this item for one example: 120748494865

[audiogeekess]

Thanks for all the help and for tolerating my ignorance--I'm learning though thanks!

Looking at the schematic I beleive those are non polarized capacitors because of the 2 parallel lines for the cap schematic symbol. So I guess I'll get ceramic disc caps. I don't understand what the dot is for in the symbol though on the voltage input and the two dots on the output cap.

[ChrisA]

Originally Posted by audiogeekess

So order this 7805 from mouser? :

LM78M05CT/NOPB National Semiconductor (TI) Linear Regulators - Standard

It is the LM78M05CT/NOPB TO-220.

Even Radio Shack will stock these. I typically buy stuff like this from Futurlec, The Electronic Components and Semiconductor Superstore. They 25 cents each there. I see some guy on ebay has them three for 99 cents with free shipping. The 7805 is one of the most common parts on Earth.

[audiogeekess]

Picked up a LM7805, along with .1 uF cap for output power, from Radio Shack the other day. (I have yet still to pick up a .33 uF cap for input power since radio shack doesn't stock this cap--don't know how much this will help the sound.)

Powering the FIIO D3 with it. It sounds better than the stock switching power supply. Switching back and forth in A/B tests, the LM7805 (along with the $28 13.8V Pyramid 3A regulated power supply feeding it) has more clarity, separation--less muddiness. Now I have to go through my entire collection again as some albums that didn't sound that good before, sound great--pretty cool.

Btw, just today I noticed I had an LM317T on a board I harvested from today. I think I'll try out this regulator and A/B it to the LM7805.

[jamesdb]

Try reading this article on 24V supplies if you want the best, will need a few more part, but may be worth it for a DAC depending on your amp & speakers.24-Volt Aikido Amplifier with the 6GM8 & Aikido hybrid power amplifiers

[audiogeekess]

Originally Posted by jamesdb

Try reading this article on 24V supplies if you want the best, will need a few more part, but may be worth it for a DAC depending on your amp & speakers.24-Volt Aikido Amplifier with the 6GM8 & Aikido hybrid power amplifiers

Thanks I'll check it out. I have a very good amp and speakers btw, I can hear subtle little changes easily. It just keeps getting better and better every little thing I do

Behringer A-500 (tweaked a lil) + Infinity RS 2001 is what I have. Btw I accidently blew my tweeters today and got replacements out of Infinity SM-62 I picked up locally from Craigslist for $40. Sounds the same if not slightly crisper/better. I did notice the crossover board & components of the SM-62 were about 1/5th the size of the crossover in the RS-2001--no wonder the RS-2001 sounds so much better not to mention larger cabinet. These RS 2001 speakers are pretty darn nice!