[MacDEF]

1) Any version of the Cosmic

2) KurtW's META42

(seriously, I was blown away by it -- much better than I would have expected)

3) PortaCorda/Total AirHead/JMT-built tin -- these all have their strengths and weaknesses so I put them at the same level

I haven't heard a Supreme, so I don't know where it would fall (between 1 and 2 or 2 and 3).

Also, someone correct me if I'm wrong, but you can't really just say "META," right? Aren't there myriad ways of building a META?

 

[JMT]

Quote:

Also, someone correct me if I'm wrong, but you can't really just say "META," right? Aren't there myriad ways of building a META?

Correct, but the "META" designation refers to the board itself....the foundation for any of the variants.

 

[slindeman]

Ranked according to sound quality:

1. Tangent's META42 with AD843s
1. Headroom Cosmic

I didn't listen enough to come to any firm conclusion, but they are both very good sounding. My gut impression was that the META42 was better, but I would need a lot more time to make any real decision. Both, however are too large/heavy for my uses. Both use chips that aren't really designed for portable use, hence the need for bricks o' batteries. An AC powered META42 with AD843 would be a marvelous non-portable amp and is on my list to do.

2. META42 with AD823

This I just listened to last night (I'm building it myself). Amazing sound for the price, very portable with great battery life.

3. "47" / cmoy

The sound is good, but it lacks the details, punch, and clarity of the above amps. I can't see any reason to recommend these now that I've heard META42 with AD823, the extra $20-$30 in parts cost gives you an extra $100-$200 in sound quality.

I haven't heard the Total Airhead or Porta-Corda. I do really like the opamps used in the Porta-Corda so I imagine I would like it a lot also.

Overall I think the META42 with AD823 is the best portable headphone amp for my needs since it combines low cost, small size, battery friendliness, and great sound all in one. Plus it drives the HD600 very well.

 

[andrzejpw]

Hmm, I'm not sure I would discount the JMT cmoy just yet. I mean, I haven't listened to a Meta yet, but at the WOH tour, I was floored. His amp just sounded THAT good for the price.

 

[kelly]

Isn't the 8620 more effecient? It's said to be on par if not better than the AD843. If so, it seems like it would be a better "portable" choice than the AD823. ??

 

[fiddler]

Kelly, according to Tangent's opamp reviews, the AD823 is good for portables because it can tolerate very low voltages, all the way down to around 3V.

 

[kelly]

Quote:

Originally posted by fiddler Kelly, according to Tangent's opamp reviews, the AD823 is good for portables because it can tolerate very low voltages.

I realize that. What I'm saying is--doesn't the 8620 meet this criteria as well? I don't think Tangent was ready to comment on that opamp yet.

 

[JMT]

The 8620 definitely sounds richer and fuller when compared to the 823 in my opinion. However, it also costs more than 3 times the 823 (when you factor in the cost of the adapter). I just received some 843s and will comment once I install them.

 

[fiddler]

Tangent's done some tests and found that the 8610/20 can distort at voltages lower than 9V.
" Just beware that the chip isn't performing its best at 9V and lower. Personally I would hesitate to use this chip for a single 9V battery amp."

 

[kelly]

Quote:

Originally posted by JMT The 8620 definitely sounds richer and fuller when compared to the 823 in my opinion. However, it also costs more than 3 times the 823 (when you factor in the cost of the adapter). I just received some 843s and will comment once I install them.

Can you settle the efficiency issue while you're here?

Is the 8620 equally efficient to the 823 or will you need to eat through your batteries faster to get good sound out of it?

 

[fiddler]

I think the 8620 has pretty low current draw, just requires pretty high voltage to sound its best.

 

[andrzejpw]

Is anyone else interested in an 843 and 8610 comparison?

 

[eric343]

The AD8610 has one fifth the current draw (actually about one 2.5th, since two are needed) but needs 3x the voltage, according to Tangent. Ppl likes it all the way down to 6V.

 

[fiddler]

Quote:

...actually about one 2.5th...

You must mean two fifths?

 

[JMT]

Quote:

Is the 8620 equally efficient to the 823 or will you need to eat through your batteries faster to get good sound out of it?

I won't use the 8620 with a single 9v set-up. I agree with tangent, it needs better than 9v to really do what it can do. For a single 9v supply, you're better off saving the cost of the chip and adapter. I know that settles nothing.