This has been in the works a while. At the request of friends (and a few critics) I've designed my own portable/desktop amp--The Objective2 (O2 for short). I just published the third and final main article to my blog.
It's a very objective approach (what would you expect from an electrical engineer?) at a low cost "one size fits all" headphone amp. The goal was to show how much performance is possible on a limited budget. It's designed to outperform even far more expensive desktop amps using solid engineering rather than audiophile designer parts or mythical topologies.
For now it's a DIY amp but it's a free open source design and a few commercial companies have already expressed an interest in offering it in various forms. Some have called it the spiritual successor to the Cmoy but the performance is in an entirely different league (sorry for not being more modest!). Some highlights:
* Enough output even for difficult headphones like the full size HiFiMan Planars and 600 ohm Beyers (7 V RMS and lots of current). It will drive nearly any headphone from 16 - 600 ohms to "live" levels.
* Completely silent even with the most sensitive BA IEMs (zero hiss with 131 dB S/N )
* Near zero ohm output impedance (0.5 ohms)
* Very low distortion of any kind--some tests push the lower limits of my dScope audio analyzer.
* ~8 hours battery life for the normal version & ~ 30 hours for the low power version
* Indistinguishable from Benchmark DAC1 in blind listening tests
* Switchable gain for use with different source/headphones
* Unique battery rundown protection
* DIY friendly, self contained on a single PC board, no surface mount parts
* Designed for a rugged inexpensive all aluminum case with a pre-made customizable front panel available.
And, perhaps the best part: You can build the fully functional self contained PC board for around $30 in parts with everything but the bare board available from Mouser.
The performance of this amp, as measured on professional instrumentation, genuinely rivals the well regarded headphone amp in the Benchmark DAC1 and is significantly quieter. It also beats every other amp, overall, I've ever had on my bench--especially its closest competitor the AMB Mini3.
I welcome feedback on the project and hope it develops into something worthwhile. I'm not looking to make any money from it in any way. Here's the link to the final article which has links to the earlier information as well:
http://nwavguy.blogspot.com/2011/08/o2-details.html
I have put together a fault finding guide on the O2 (post #3775) that gives step by step testing and checking procedures. Click HERE
It's a very objective approach (what would you expect from an electrical engineer?) at a low cost "one size fits all" headphone amp. The goal was to show how much performance is possible on a limited budget. It's designed to outperform even far more expensive desktop amps using solid engineering rather than audiophile designer parts or mythical topologies.
For now it's a DIY amp but it's a free open source design and a few commercial companies have already expressed an interest in offering it in various forms. Some have called it the spiritual successor to the Cmoy but the performance is in an entirely different league (sorry for not being more modest!). Some highlights:
* Enough output even for difficult headphones like the full size HiFiMan Planars and 600 ohm Beyers (7 V RMS and lots of current). It will drive nearly any headphone from 16 - 600 ohms to "live" levels.
* Completely silent even with the most sensitive BA IEMs (zero hiss with 131 dB S/N )
* Near zero ohm output impedance (0.5 ohms)
* Very low distortion of any kind--some tests push the lower limits of my dScope audio analyzer.
* ~8 hours battery life for the normal version & ~ 30 hours for the low power version
* Indistinguishable from Benchmark DAC1 in blind listening tests
* Switchable gain for use with different source/headphones
* Unique battery rundown protection
* DIY friendly, self contained on a single PC board, no surface mount parts
* Designed for a rugged inexpensive all aluminum case with a pre-made customizable front panel available.
And, perhaps the best part: You can build the fully functional self contained PC board for around $30 in parts with everything but the bare board available from Mouser.
The performance of this amp, as measured on professional instrumentation, genuinely rivals the well regarded headphone amp in the Benchmark DAC1 and is significantly quieter. It also beats every other amp, overall, I've ever had on my bench--especially its closest competitor the AMB Mini3.
I welcome feedback on the project and hope it develops into something worthwhile. I'm not looking to make any money from it in any way. Here's the link to the final article which has links to the earlier information as well:
http://nwavguy.blogspot.com/2011/08/o2-details.html
I have put together a fault finding guide on the O2 (post #3775) that gives step by step testing and checking procedures. Click HERE
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And while you might say "professional" others fall asleep reading some of my articles or their eyes glaze over. I'm still trying to improve my writing and presentation skills and have a ways to go.
