[dta116]

Just finished my Meta42 and will follow with pics tonite.
Maybe I overdid it, It draws 35ma and battery life is only 5.6 hrs.

Now for another project - Can you Pro's tell me of the best project for a wall-powered hedphone amp to use with my home stereo system?

I know you will have questions, but I don't know what I want, I really don't know what is available.

NEEDS: Headphone amp w/preamp out.

WANT'S: maybe 3 headphone outs & preamp
1 for Senn HD580 (300 ohm)
1 for Beyer DT 770 pro (250 ohm)
1 for Grato SR 225 (32 ohm)
Preamp out

I prefer a little less brightness (listen for hours at a time).

I realize others have their own preferences, but I am only looking for input, and it is as always appreciated.

Thnak you for your support.

 

[Andrew LB]

Quote:

Now for another project - Can you Pro's tell me of the best project for a wall-powered hedphone amp to use with my home stereo system?

I hear the Kevin Gilmore Dynamic Class A amplifier kicks serious butt. www.headamp.com

 

[eric343]

I'll second the vote for the KGCA (Kevin Gilmore Class A - Kevin's design for dynamic headphones. The other big ones around here are the KGSS, or Kevin Gilmore Solid State [for electrostatic headphones] and Blue Hawaii/Bob, his tube-solid-state hybrid that costs a small fortune to build but apparently sounds amazing, also for electrostatic headphones... not many have built it though.)

 

[dta116]

Thanks Guys' Me Thinks I'll stick with solid state for now, the tube amps are definately better sounding, but for my needs the time and expense is better left for a future project.

I guess that narrowed my choices eah?

 

[finleyville]

Even though I am very happy with my META42 that I use only for home use (no batteries,) I now wished I had built Kevin's amp. The design looks very good and I have only heard great things about it's sound. However, the price of the KGCA amp was definitely more than my META using the same quality parts. Good luck and happy soldering!

 

[dta116]

I finally got the Pics, description, ect. uploaded last nite.

Meta42 Project

For you critics out there, I accept criticism.

 

[finleyville]

That looks very well done! Makes my META innards look neolithic. If you do tackle KGCA amp you should have no trouble at all. OR... You could start making your own interconnects. That will be my next project.

 

[tangent]

35 mA power draw isn't excessive for a META42. You can get it a lot lower, but you'll sacrifice sound quality.

The 5.6 hour run time also makes sense -- those look like Plainviews which are only rated for 170 mAh. I imagine they're wired in series, so you still only get 170 mAh out of a pair. You're getting better life than they say you should, so be happy.

 

[dta116]

Actually Tangent.......
I calculated the actual runtime to be only 4 hrs. (That is to a flat battery). But in real world it's probably about 3 hrs.
The way I tested the time was with an hour meter hooked up to the ckt. until it quit.

I have not yet actually put the thing to use !

 

[eric343]

VERY cool and professional META!

And thanks to the link hawking Cardas QE at $40/lb!

 

[dta116]

hey, Eric343

Noticed a ETA42 as your personal unit. Would like to see it.
Where's the "M" or is a different unit?
Any chance?

Thanks.

 

[eric343]

http://www.tangentsoft.net/audio/meta42/history.html

The ETA42, or eric343/Tangent/Apheared 42, is Revision I.

The META42 is essentially the result of some heavy-duty collaboration between Morsel and Tangent 'behind the scenes'; so I guess it should really be the MTA42 - I didn't do much for it apart from the fact that it evolved (I guess - Morsel or Tangent would know better!) from the board Tangent and myself worked on. The only real similarity between the ETA42 and META42 is the fact that both use EL2001 output buffers, have provisions against reversing battery polarity, use a TLE2426 railsplitter, have the signal chips and power capacitors in relatively the same place, and have a spot for a boardmount Panasonic EVJ. And the first three points are part of the original Apheared 42 design...

So basically, the ETA42 is the beta version of the META42. It works (quite well), but it's not nearly as polished or capable. And the META42 can (and usually does) sound better than an ETA42 - unless you're going all-out on the former and all-RadioShack on the latter...

There were only two ETA42s ever made (unless someone else ordered themselves some boards from the layout files that we posted while developing); one is my personal unit and the other belongs to Audio&Me.

This is what my personal ETA42 looked like when I first built it (it's since undergone a change of volume control knob and of headphone jack [BEWARE of these jacks: http://www.drsue.net/images/meta42-jack3.jpg , they're QUITE unreliable!] and I have a better digital camera!):
http://www.drsue.net/images/meta42-front.jpg
http://www.drsue.net/images/meta42-top.jpg

Pretty n00bish, eh?

Now they look more like this:
http://www.drsue.net/meta42/pictures...es/Image4.html





Ah, those were the days... I believe it's been almost a year since I built that guy... Amazing how time flies

[size=xx-small]good lord, I'm reminiscing on the 'good old days' and I'm only fifteen!

![/size]

 

[Gariver]

dta116: That's a very nice META42. It's so neat and tidy! Congratulations!

Michael Percy has the Cardas Quad Eutectic Solder...
----1 lb = $39
--1/2 lb = $21
--1/4 lb = $11

http://www.percyaudio.com

To test solders...
Stretch out equal lengths of different solders. Then check the resistance with your DMM. Results? Cardas wins! It's the best solder around, the one I always use.

 

[eric343]

Or better yet, the method I've always wanted to try is to use different solders as interconnects...

 

[dta116]

Quote:

Originally posted by eric343 Or better yet, the method I've always wanted to try is to use different solders as interconnects...

Explain please. This is a new one on me.