I soldered this and several other surface mount DACs with a unregulated 40W iron.  I think you just have to make sure not to heat anything for too long.

Quote: I tried mine with a pair of 32ohm Grados and thought it sounded pretty bad, very flat and bland sounding.  Not sure if that was a problem of impedance or just pairing.  

A 4.7uF output cap is plenty.  Into a 10kohm load which is hopefully as low of a load as it'll ever see, it has a bottom cutoff frequency of 3Hz.

Quote:   I think the problem is the cans not the cable.

A couple suggestions I forgot to mention:   First, when resoldering the right side of the PCM1794 chip, I had a lot of trouble getting the pins with the capacitors in the way.  I'm not sure how critical the locations of C18 and C20 are but if they could be moved a little to the right, the...

Just finished soldering mine together.  The build went well for the most part except I spent some time resoldering the PCM1794 over and over until some pin finally got soldered and sound came through the output.  While I've only listened to it a bit, its much much better driving headphones than...

Quote:   Well a huge thanks to tomb then.  I think those two chips saved me $30 on my digikey order not to mention the time it would have taken to ship from backorder.   Leaving the crystal leads long is a great idea.  Would make a surface mount resistor possible which would be a...

Just got my board today and ordered my parts.  When I got the board today with the two chips, I realized I only paid $5CDN for the whole package.  Do I own someone another paypal payment?   EDIT: also the 1Mohm resistor spec'd in the BOM is now obsolete. I forgot to replace it with something...

Does the IV opamp put out enough power to drive headphones directly do you think?  Is the power supply robust enough to handle such a load?  This would make a really cool single board solution for portable listening.

One thing I've always wondered, is there data to suggest that lots of simple linear regulators sound better than a single well done shunt regulator?  I can understand that seperate power supplies isolate different sections of the circuit but shouldn't a good PSU design be able to offer cleaner...

While R8 and C5 do form a low pass filter, the idea of corner frequency and that formula don't really apply since there's current being drawn out of the resistor in effect making the resistor and capacitor not a simple RC filter.  However, the basic trend still applies in that the larger the...

Quote: What tube were you using?

  Quote: EDIT:  mis-read the schematic.  Not sure why you have the pot in there though.  The DC levels don't have to be precise since there's an output cap.

While not very efficient, I learned a lot just by following threads here and picking up bits and pieces.  If you don't quite understand voltage, current, resistors, capacitors, etc, you could probably google around to find a basic electronics introduction online.  I've also gleaned a far bit...

You might have already seen this video but it might offer some insight.  Looks like akg uses a UV curable glue.   http://www.youtube.com/watch?v=3LbsQRaQD6A

So I'm determined to add some negative feedback to my CTH.  I just hate having to turn up the volume just to center the music and the idea of further attenuating the signal before amplifying it so much seems silly.  I spent forever working through the schematics with my very basic understanding...

It would be great if that were added the the CTH main site.  I remember spending 30 minutes more than once trying to track down that spreadsheet and it'd be annoying to have it become buried again.

I would recommend soft nylon sleeving which you can get off ebay from the user furryletters.  It has no microphonics.  The only downside is that it only comes in black (at least that I've seen so far).

I think the idea is that selling DIY cables and amps should not be seen as a source of income and so you shouldn't charge for labor.  DIY is a hobby, not a second job and you should be making the cables for yourself, not to sell to others.  If I sold an amp I made at the full cost of all parts...

Quote: You could string together 4 25k 1/4 watt  resistors in series which would be much easier to find in a parts box.

Quote: I think the biggest reason is that solid core wire is stiff and people tend to move while wearing IEMs.  Beyond that, solid core wires can break easier.  In a stranded cable, the individual strands are more flexible and even if a couple do break at a point, other strands can carry...

Quote: 10k, 50k, and 100k are all common values.  As the resistance gets higher, noise becomes more of a concern.  This might apply especially to you if you're using one as a passive volume control.  On the other hand, lower values place higher loads on the DAC and the amp/active monitors...

For IEMs you'll want at most 26awg if not thinner.  Also I second navships wire for a first cable.  Its nice quality and cheap, especially when you consider shipping from other places.

Is there a way to reduce the gain of this amp?  I'm already using a 100ohm output resistor and find myself using the bottom 15 degrees of my pot at most.  Even with a nice pot, the channel matching is poor at the very bottom end.  I'd also like to not use the output resistor since its probably...

Output impedance also matters.  If a PSU has a high output impedance, the voltage will drop when large amounts of current are drawn.