O2: High Performance Portable/Home Amp

[eroarex]

Originally Posted by NwAvGuy

Where are you located Rapide? There's now a European Group Buy for a complete kit.

A lot of DIY projects require purchasing from 3 -5 sources. A major goal for the O2 was to have everything on the board available from Mouser to save on shipping costs--at least in North America. For those outside North America, the group buys (so far one for Europe and one for Australia/New Zealand) should help a lot.

thanks a lot for this, just ordered the pcb from oli and the kit from jokener, thanks again, and i'm eager to test this amp myself

p.s. i've read the comments about the super fi 5pro, sadly i don't have them anymore i currently own senns ie8 and hd238 and a sansa clip to go with them and looking forward to something big like a hd650 or a hifiman he300 or he4, which i hope the amp can cope with

[CrowdAds]

[NwAvGuy]

Originally Posted by eroarex

looking forward to something big like a hd650 or a hifiman he300 or he4, which i hope the amp can cope with

I own the HD650 and the O2 drives them with ease. Some of the HiFiMan cans, however, are right at its "design limit". They're among the most difficult to drive headphones I could find anywhere.

I would suggest waiting to see what other users report with their HiFiMans, and taking into consideration how loud you like to listen, before you buy any of their more power hungry headphones. I'm working on a new article for my blog that goes into this topic in much more detail.

[Rapide_23]

Originally Posted by eroarex

senns ie8 and ... sansa clip

Slightly off topic, but its a great combo isn't it

Can't wait to get the parts to put an O2 together. Lots of group-buy threads on DIYaudio.

[The DarkSide]

I got a PM from someone in this thread, and it was accidentally deleted - please PM me again. Thanks!!!

[upstateguy]

Gearing up for mine....

[Rapide_23]

I demand build pics

[axon01]

Did something happen to the reviews at HF?

[Mid-Fi]

The two review threads that I read are still there:
Review: NwAvGuy's O2 DIY Amplifier by Shike
and
Objective2 Mini-Review by Maverickronin

[SpaceTimeMorph]

Another review for you guys: http://anythingbutipod.com/forum/sho...294#post574294

[NwAvGuy]

First, a big thank you to SpaceTimeMorph for his excellent review!

I received the final (fourth) round of prototype O2 PCBs, built up an amp, and it's the best revision yet. A few more little tweaks were made to allow using different battery terminals and making it easier to "socket" the gain resistors so they can be changed without soldering. The board is officially fully released. The baby has left the nest.

There's a bunch of revised information in the O2 Resources section including some new recommendations for wall transformers and a few other tweaks. There's also a potential group buy for front panels you might want to check out.

The group buy for the PC boards closed a few hours ago. Oliver is buying at least 750 boards! Several have asked if that's a new record for a DIY group buy.

A few asked for a high resolution shot of the PCB so here's the final board (hastily soldered together in a rush):

[Soaa]

That is a thing of beauty...

[Confispect]

Does look cool I don't know to much about (amps/whatever) but it looks nice.

[koolkat]

Beating the crap out of RSA, at a fraction of the price.

[msjjr]

Hi. I've just come across this thread and I would love to get one of the boards as well. I'm in the Toronto, Canada area and I'm not part of a group buy at all. Can anyone tell me how to acquire one, or is it too late? BTW, I'm not a DIY'er so I can't build one myself. Thanks.

[Mid-Fi]

Originally Posted by msjjr

Hi. I've just come across this thread and I would love to get one of the boards as well. I'm in the Toronto, Canada area and I'm not part of a group buy at all. Can anyone tell me how to acquire one, or is it too late? BTW, I'm not a DIY'er so I can't build one myself. Thanks.

MrSlim in Ottawa was making and selling 02 amps. It looks like the offer is now closed but you might consider contacting him and see if he has any spares.

[msjjr]

Thanks. I did PM him already, but hadn't received a response (yet) and I thought I'd ask here. Thanks.

[Limp]

DIYaudio.com is where it's happening.

All group buys are now closed, but it wouldn't surprise me if another were to start shortly, the interest has been amazing.

Ollie, who did the initial run, ordered a few hundred extras to sell to people arriving a bit late. Sign up and ask if he's still got boards unspoken for.

Linky

[msjjr]

Thanks for the help.

[MrSlim]

Originally Posted by msjjr

Thanks. I did PM him already, but hadn't received a response (yet) and I thought I'd ask here. Thanks.

Sorry, I've been busy elsewhere.. and didn't think to check my PM's here.
I just replied to you

[mrcl_kk]

@NwAvGuy: Does the use of the low power op amps affect the calculation for input overload (5/X for battery 7/X for AC)?

Building the O2 will be my first DIY experience, but I'm affraid it will be unnecessary to build one in the first place because of the haedphone I use.
I use Grado headphones and notice others to use a headamp for them. But the way I see it, I wouldn't have to use one for the lack of gain of for instance my Ipod (or anything else but an Ipod). Are there other diffirences then just the low output impedance of the O2 that will affect the sound?