[peranders]

I have finally made my first SMD audio project. It's a headphone amp using OPA627 or OPA134 or AD8610 together with a high speed buffer BUF634.

Works excellent, sounds good also.....

[randytsuch]

Looks cool.
Did you design the PWB yourself?
What kind of cans do you use?  I have a pair of AKG 1000's, so a headphone amp does me no good, they need at least a few watts to drive them.
BTW, I stumbled across your website a while ago, and was liked it.

Randy

[peranders]

1 Thanks!

2 Yes, says so on the pcb but I haven't made them. They are made in a factory.

3 Sennheiser HD545 reference (quite good)

[JoshK]

you are the only other person I have bumped into that owns the Senn 545s.   On the headphone forums I have read that some will prefer it to the 600s because it is a bit more forgiving and easier to push.  I haven't tried the 600s.  I use a McCormack MID headphone amp that sounds great!

[peranders]

When I bought these phones I listened to > 20 types, including HD600. I thought then that 545 sounded very neutral. They had no "pop sound". One other fact was that they were on sale 130-150 dollars was price.

[harvardian]

Peranders,

How timely! We are adding a headphone output to our PGA2310 version of the APOX-3. We will be using the OPA134 for input buffering into the PGA2310, a opa2132 as a diff amp (balanced->se), then the BUF634. It will taken out of the circuit with relays. What kind of regulators are you using. We are attempting to make the APOX-3 fully dual mono, which means using opto-isolators to keep the grounds separate.

Any other suggestions?

Dale

[peranders]

I use LM317 and LM337 SMD. You can download the schematics if you want to know more exactly what parts I have used.