X-Altra HPA-1 Class A Headphone Amplifier

[Bonsai]

This depends on how efficient the headphones are. The HPA-1 will drive 16 Ohms - it current limits at about 250-300 mA output. If you phones are efficient then they will be load enough well before this point, otherwise not.

I would try it, and if you’re not happy, then build a second amp.

 

[Mooly]

@LarsLWO Why are you posting under two identities within this thread?

 

[LarsLWO]

I‘m not. I‘m working together with my roommate. Isn‘t that okay?

 

[Mooly]

That is OK but I hope you understand why we have to ask.

 

[Vrystaat]

Andrew, thanks a lot,it is much appreciated ! I have received the board today. Just to good to be true with this Post Office in this broken place.
Now to order those minute nipper components !

 

[jaycee]

An interesting design Bonsai. I'll play with it in LTSpice, and then I might build this into my own DAC rather than the simple diamond buffer I was planning to add

 

[kaliwraith]

Bonsai, can you combine shipping on the headphone amp and phono preamp?

 

[Bonsai]

Yes, anything you want.

I have a power supply board coming for the headphone amp (it’s also for the coming line level pre). It’s about 2 weeks away if you want to wait for that as well.

 

[Bonsai]

Andrew, thanks a lot,it is much appreciated ! I have received the board today. Just to good to be true with this Post Office in this broken place.
Now to order those minute nipper components !

that’s great!

 

[kaliwraith]

Yes, anything you want.

I have a power supply board coming for the headphone amp (it’s also for the coming line level pre). It’s about 2 weeks away if you want to wait for that as well.

Very cool. Yeah waiting is no problem. I am very slow to complete projects...

 

[Bonsai]

Hello, the new Hifisonix Standard Linear PSU is up on my website here

Hifisonix Standard PSU

This is the ideal way to power the HPA-1 (and coming line level preamp)

 

[sonidos]

Wonderful! Of course, my finger has been on the trigger for the last couple of weeks. Looking forward to taking the next step.

 

[Bonsai]

 

[sonidos]

The psu board has arrived. Thanks very much, Andrew. Is the BOM available yet? No rush, I'll probably end up finishing this up in the Fall as I'm going to order the line-level preamp pcb when it's ready.

 

[Bonsai]

Sorry Sonidos,

Rushing around the last few days - house Reno’s finished now though. I will put it up today or tomorrow. It’s basically done but I have to check it first.

 

[sonidos]

 

[Bonsai]

Standard PSU BOM is checked and now up on the HPA-1 page here Hifisonix Standard PSU

 

[wirewiggler]

Andrew,
I received both boards thank you, I was not planing to build the headphone amp for a while but I was short a few parts for a project I was working on and went ahead and ordered parts for it. I have to admit i was surprised how affordable the parts were - about $30 - I had heat sinks already. I guess one reward for switching to smt parts is they are much more affordable parts.

Thanks
Bill

 

[wirewiggler]

Quick question regarding solder paste, our summer temps have been over 100 Degrees Fahrenheit in my workspace should I be storing the paste solder in the refrigerator? I have herd of people having issues with what I think is probably separation of the components.

Bill

 

[Bonsai]

Hi Wirewiggler,

Yes SMD parts are cheaper - mainly because that’s where the volume is nowadays. For example, I worked for a large semiconductor company for 20 yrs - we got out of TO92 already in 2007.

Re paste storage, unfortunately I am not able to advise on that - I use 0.5 mm solder for all my SMD assembly work.

Maybe one of the other diyAudio members would care to advise?