Did you go single-supply on that one? (I'm asking because the TO92 part next to the battery looks like a TLE2426, but there's only one reservoir cap and two leads from the PSU board to the main board) If so, what made you choose that over the 'standard' CMoy virtual-ground option?

Oops. I will immediately edit the opening post, seems I was misremembering. Shouldn't have quoted names before double-checking. (edit: Oh dear... the only HV design on diyforums/Bezaar is the Torpedo, and that one isn't even labelled Millet. Man did I get that one wrong... )   Then again...

By low voltage, I mean "can be powered off a 24V/1A AC wall wart" :) . Most of the well-known tube designs need fairly high voltages, and require doing your own mains wiring with a toroidal transformer. For people who want to avoid that, what options are there? I've been reading through...

Quote: Are you talking about the metal case? "Package" is the wrong word, so that's why you can't find it. They're called "enclosures", and the one listen in the pupDAC BOM is the Hammond 546-1455C801BK, Mouser part no. 546-1455C801BK.

Here are some more thoughts on STX vs amp: http://www.head-fi.org/t/632163/essence-stx-or-headphone-amp-help-appreciated I'd say that if you already have the STX, keep it. DT770s are not exactly hard to drive, and the headphone amp built into the STX isn't bad at all.

Can't comment on whether you really need them to be micas, but they're $1.50-$2.00 each and you need two of them. Doesn't sound that expensive to me, considering that you're building a project that costs around $80 in parts alone (without an enclosure).

This may be a stupid question - I'm not an expert on this stuff by any stretch of imagination - but: In most of the solid state amp designs, a single BUF634 per channel seems to be accepted as being powerful enough to drive most headphones. Is there a tube/hybrid specific reason why you have...

... speaking of which, I'm running a configuration similar to yours (with 0.22uF input caps, though) and getting about 30mV DC offset on the headphone jacks. Is that still kind of okay, or should I think about output caps instead of/in addition to the input caps?

Quote:     "Looks okay" is probably not enough, if the resistor is actually fried, it might not have been the only part to take damage. For what it's worth, my X1 is back to life and it still has its old R44 in there, which measures about 3 Ohms (that measurement should be accurate, as...

Quote:   What's the point of the 499R resistor in the signal path? Is it simply some from of protection in case someone turns on the amp while the volume pot is turned fully to the right (i.e., shorted)?

I got the boards at pcb-devboards.de. I think Mr Ulrich will ship to the US if you ask him, but I'm not sure whether it's economically sensible to do so. For prototypes, the prices are hard to beat (except mayber if you have them done in China) - I found a few similar offers for one-sided...

@Avro_Arrow:   The boards are dual-layer with plated through holes. On the A47, the bottom layer hosts the star ground, on the PSU, it's a ground plane. But yeah, next time I'll try whether I can get away with a single layer. Thanks for the hint!

Those two are a bit rough still, but they are my first PCB designs and my first proper solder works, so I'm really quite pleased with the way they turned out!   9VAC to +-8VDC power supply for small headamps (7808/7908 linear regulators, 2200u Nichicon reservoir caps):      ...

Thanks to everyone who helped! I finished the PSU and an Apheared 47 today. Have some pics :) :         ... and both worked just fine from the start!

I'm not a doctor, so I can't really comment on whether you should put hydrogen peroxide into your ears at all, but whatever you do, do NOT use the concentrated 30% hydrogen peroxide. (H2O2 usually comes in 3% and 30% solutions, the concentrated one is certainly not meant to be put anywhere...

So much information - great stuff :) !   @agdr: I need to double check those ripple specs again. I wasn't really aware of that until now (and surprisingly, most head amp diy PSU designs out there do not seem to use parallel caps there). The LT regulators are a bit expensive. I may well try...

Do I need some form of inrush current limiting for those caps? The simulation shows 7A of charging current during the first charging phase, which is way too much for my AC Adapter and the diodes of course. Are there any real-world effects which do not show up in the situation and help prevent...

That would be great, as I can save a lot of space with 16V caps (or go for more uF at the same size). I'll shop around a bit and see what I can find :) .

Thanks for your input! New plan, possibly better: Using a 12V AC supply (so amplitude 16.8V), 12V regulators and 35V 2200uF caps. Simulation gives a load of about 1.5W (although purely resistive), and the ripple never drops below 15V, giving at least 3V of headroom to the regulators. That should...

Hi everyone,   the following design is meant to be used as a PSU for various CMoy-like projects. In its current form, it should take 8V AC from a wall wart and output +-8V DC. The reason for this approach is that I do not want to mess with mains wiring myself (otherwise I would have gone...

Thanks again, after changing the TDA2030, it's back to life :) .

Quote:   Thank you so much! Just to clarify, you are talking about DC offsets on line out/headphone out, right?  (By the way, what's your best guess on the value of R44? Just in case something is wrong with it, it'd be great to know what I should try to replace it with.)

Hi :)   So.. I got an Aune X1 DAC/Headamp today - sounds great by the way - and because I am a curious guy, I opened the case to check the interior. Because I am an idiot, I missed a small plastic ring when putting it back together, which shorted the heatsink of a TDA2030A in the power...

Okay, I can see why it's not too sensible starting with a $500 project... Concerning suppliers in Germany: We _do_ have big online stores like conrad.de and reichelt.de, and it's no problem getting resistors and capacitors from there, I think conrad even has the Alps blue potentiometer and...

Thanks for all the info so far. I'm quite sure I won't be able to resist the temptation . What's a good amp to start with? Should I try a CMoy/Mint first or is there any sense in starting directly with a Pimeta/PPA? I've got to say those tubes look quite sexy too...