@1Time Unfortunately, I don't have any other recommendations for you other than to use batteries. Regulated wall warts tend to be rather overpriced given the fact that common voltage regulator chips only cost around 20 cents. Perhaps this helps just a little. Since my first amp was a cmoy...

Quote: Originally Posted by 1Time That is funny. I'm neither the McCoy nor the Scottie type, but from what I understand from the paper I received along with my cMoy, the measured output from a non-regulated adapter will be greater than its labeled rating. Quoted from this paper...

I finally finished assembling my PPAv2 and a quick test with cheap earphones even revealed that it basically plays music, BUT my working voltages are seriously off. Measured at the C5 caps (which feed the op-amps), I get +/-5V und +/-6.5V on the left and right channels and, most strangely...

Quote: Originally Posted by Ampersand As I can't get my hands on any 627/637's, I was thinking of using AD797 on L/R/G. Anyone try this? Or see some glaring problem with using these? I don't think AD797 is unity gain stable, so it probably won't work in the ground channel. In the...

Shame on me for not noticing that detail in the picture - thanks again

Which way are the output transistors positioned? The board has a kind of marking (a thicker dash) on one side of the transistor "sign" printed on it, but does that mark the labeled or the metallic side of the transistor? Thanks for your answer(s)

I'm just building a new power supply for my amp and I'd like to add some serious low pass filtering before the regulator. I probably shouldn't put more than 5000µF in that position and I can use about 6 Ohms (to limit the voltage drop). Is there any point in "spreading" these 5000µF/6R over...

Quote: Originally Posted by holland Any pictures? How many pins? Two 8-pin SOIP chips. I'll post pictures as soon as I have time.

Quote: Originally Posted by holland For those who have it, what opamps does it use? There's still no info on that, the markings of the chips have been removed.

Well, I've made up my mind: the K701 is going to stay, the rests goes back. The K601 doesn't quite cut it, I could just as well keep my HD580. The K701's soundstage is just so much lovelier (especially for movies) and the K601 simply lacks the K701's "perfection" in detail and positioning...

There are two ways to get rid of hiss: - use headphones with a higher impedance or - increase the impedance of your headphones with an impedance adapter (building instructions are somewhere around here, it's basically two resistors plus wiring) Out of curiosity: Which headphones were you...

Quote: Originally Posted by tbonner1 How do you think the bass on the 601 compares to the 701? The 601 sure has an emphasis on midbass, it's really more a question of presence than quality - the 601 gives me "more" bass but the 701's might extend a little deeper. Accurency-wise...

Still burning 'em day and night but, honestly, so far I don't see much change. Quote: Originally Posted by Chris_Himself the K701 sounds like crap out of the box apparently. Ouch - that's like saying Pamela Anderson looks like crap without implants (then again, ...). My...

Introductory stuff ... Since I have the pleasure of welcoming all these headphones to my home for several days and I know how needy one feels for information when trying to decide for a pair-o-cans, I want to share some impressions with you. Sure, much has been said about K701 vs. K601, but I...

Nope, not neutral because of the treble emphasis. Whether 100% neutrality makes good headphones is on another page, though. I consider the sparkly treble an asset of the Beyers, despite the fact that I, quite frankly, can't stand it. What would we flame about if all headphones were equal?