Corda HA-2
post-228834
Thread Starter
Post #1 of 27

lini

Thought the last line in Citizen Kane was nosebud.
Joined
Jun 22, 2001
Messages
6,117
Reaction score
21
Joined
Jun 22, 2001
Posts
6,117
Likes
21
Just in case nobody mentined it, yet: Jan should have relased the Corda HA-2 - a Corda HA-1 on steroids
- by now. Cost is 560 Euro/US$.

Greetings from Munich!

Manfred / lini

P.S.: Further technical infos as sent to the chosen few
by Jan:

** 2 headphone outputs (0 Ohm / 120 Ohm output
impedance).

** Maximum output 13V / 250 mA.

** Variable crossfeed filter switch:
1. Stereo
2. Low level crossfeed
3. Medium level crossfeed

** Input impedance 13 kOhm

** Gold-plated input jacks.

** Silver plated headphone jacks (Neutrik).

** Silver plated heavy duty switch (C&K).

** Alps Blue Potentiometer.

** 7 Watts toroidal transformer (Talema).

** 110V and 220V versions available.

** Power uptake 4 Watts

** Build-in groundloop breaker.

** Schottky rectifying diodes in the power
supply.

** Double regulated voltage lines.

** Low impedance electrolytic buffer capacitors
(Panasonic).
Total Buffer capacity 21.000 uF.

** Polyesterfilm bypass capacitors in the power
supply.

** Polystyrol and polypropylen (Vishay)
capacitors in the signal path.

** Metalfilm resistors in the signal path.

** Double sided PCB with 70 um copper.

** LM6171 opamps biased into class-A using
LM334 current sources.

** BUF634 buffer amplifiers at each headphone
output channel.

** Star-grounding.

** Ultra short signal paths.

** Signal paths and signal path components at
the bottom side
of the PCB for maximal shielding.

** Sturdy aluminium enclosure with anodized
front plate (8 mm)
and backplate).

** Laser engravings.

That's it. I also received some photos, but I've got no place to post 'em in proper size...
 
     Share This Post       
post-228866
Post #2 of 27

kpfeifle

100+ Head-Fier
Joined
Nov 26, 2002
Messages
179
Reaction score
25
Joined
Nov 26, 2002
Posts
179
Likes
25
Will the HA-2 also be offered in kit form?
 
     Share This Post       
post-228884
Post #3 of 27

lini

Thought the last line in Citizen Kane was nosebud.
Joined
Jun 22, 2001
Messages
6,117
Reaction score
21
Joined
Jun 22, 2001
Posts
6,117
Likes
21
Kevin: The mail doesn't mention a kit, so I don't know a definitive answer. But the board has quite a lot of parts, and there are parts on both sides of it - so maybe (speculation!) Jan considers it too difficult for the typical diy-builder...

More greetings from Munich!

Manfred / lini
 
     Share This Post       
post-228928
Post #4 of 27

Jan Meier

King Corda
Member of the Trade: Meier Audio
Joined
Jun 21, 2001
Messages
831
Reaction score
111
Joined
Jun 21, 2001
Posts
831
Likes
111
Dear kpfeifle,

"Will the HA-2 also be offered in kit form?"

No, definitely not. Experiences with the HA-1 have been quite discouraging and the HA-2 is simply a few levels more difficult to build. The double sided board also makes repairs/desoldering very difficult.

Cheers,

Jan
 
     Share This Post       
post-228976
Post #5 of 27

BoardC3

500+ Head-Fier
Joined
Jun 5, 2002
Messages
800
Reaction score
12
Joined
Jun 5, 2002
Posts
800
Likes
12
looking at your website i noticed a pre/power amp combo i was wondering when you will be selling it and about how much it will cost? (i need to know soon because im about to buy an integrated amp) thanks,
chris
 
     Share This Post       
post-229000
Post #6 of 27

Jan Meier

King Corda
Member of the Trade: Meier Audio
Joined
Jun 21, 2001
Messages
831
Reaction score
111
Joined
Jun 21, 2001
Posts
831
Likes
111
Dear BoardC3

I do have plans for a small power amplifier that those will not be realized within the near future. I have many other ideas that I like to give a higher priority. Can't do it all at the same time.

Sorry,

Jan
 
     Share This Post       
post-229062
Post #7 of 27

kpfeifle

100+ Head-Fier
Joined
Nov 26, 2002
Messages
179
Reaction score
25
Joined
Nov 26, 2002
Posts
179
Likes
25
Quote:

I have many other ideas that I like to give a higher priority


Jan:

Would you care to share? What can we expect in the near future?
 
     Share This Post       
post-229126
Post #8 of 27

andrzejpw

May one day invent Bose-cancelling headphones.
Joined
Jun 25, 2001
Messages
6,636
Reaction score
10
Joined
Jun 25, 2001
Posts
6,636
Likes
10
Whoa, a new corda, and with 1/4 jacks to boot!
So Jan, um, any review samples?


Jan: any estimate on the release?
 
     Share This Post       
post-229137
Post #9 of 27

Gergor

1000+ Head-Fier
Joined
Jun 7, 2002
Messages
1,089
Reaction score
11
Joined
Jun 7, 2002
Posts
1,089
Likes
11
Is it a prehead without the preamp option?
 
     Share This Post       
post-229249
Post #10 of 27

kelly

Herr Babelfish der Übersetzer, he wore a whipped-cream-covered tutu for this title.
Joined
Jan 1, 2002
Messages
5,435
Reaction score
11
Joined
Jan 1, 2002
Posts
5,435
Likes
11
Quote:

Originally posted by Gergor
Is it a prehead without the preamp option?


It has a smaller transformer and only one buffer per channel (Prehead has three) but Jan claims there is no audible difference with high impedance phones such as DT931 and HD600 but that there may be a *slight* difference with low impedance phones such as Grados. I trust Jan but I'll still hold out for my own audition--maybe sometime next year.
 
     Share This Post       
post-229461
Post #11 of 27

Gergor

1000+ Head-Fier
Joined
Jun 7, 2002
Messages
1,089
Reaction score
11
Joined
Jun 7, 2002
Posts
1,089
Likes
11
Very tempting... even though most of my headphone are low-Z. I recently bought a HD580 and I'm very happy with it, maybe I'll get it to drive the Senn exclusively...
 
     Share This Post       
post-229544
Post #12 of 27

Jan Meier

King Corda
Member of the Trade: Meier Audio
Joined
Jun 21, 2001
Messages
831
Reaction score
111
Joined
Jun 21, 2001
Posts
831
Likes
111
Dear Headfellows,

"Would you care to share? What can we expect in the near future?"

Right now, with Christmas time coming up, I'm completely overloaded, so no new projects for the next few weeks.

However, if time is there I hope to bring a passive crossfeed filter that can be placed in front of every ordinary headamp. It basically is the natural crossfeed filter with a build-in compensation for the load impedance represented by the amp.

More recently Harry and I started testing various interconnect cables. To be honest, we find prices of most interconnects rather overcharged and consider bringing some cables of our own.

Next project might be a new low-budget amp. an upgrade of the HA-1. However, this will not be launched within the next half year. I simply don't have the time.

And last there's that small poweramp...

But we shouldn't forget to mention that .........

Oops, I won't tell you that


"any estimate on the release?"

I didn't have time to update my home-page yet but the HA-2 should be available by the end of this week. Harry is soldering like a world-champ right now. No review samples though, unless there's a big meeting coming up.

"It has a smaller transformer and only one buffer per channel (Prehead has three) but Jan claims there is no audible difference with high impedance phones such as DT931 and HD600 but that there may be a *slight* difference with low impedance phones such as Grados."

The PREHEAD is extremely powerfull and will output 5 Watts (800 mA peak current) per channel at a 16 Ohm load! It even can drive high-efficiency loudspeakers

The HA-1 has an output of 250 mA per channel but with headphones this still is way more than enough. As whether sonic differences are to be expected from stacked buffers, please be aware that with both the PREHEAD and the HA-2 the buffers are placed within the feedback loop of a controlling opamp. It's the opamp that determines the quality of sound.

Small sonic differences might also be present if your mains power is strongly polluted, as the PREHEAD has a build-in mains-filter. However, both amps have a two step voltage regulation so again, differences will be small.

Cheers,

Jan
 
     Share This Post       
post-229551
Post #13 of 27

Gergor

1000+ Head-Fier
Joined
Jun 7, 2002
Messages
1,089
Reaction score
11
Joined
Jun 7, 2002
Posts
1,089
Likes
11
Now I'm extremely tempted. Any pics you'd share with us?
Is it the same size as HA-1 or bigger?

Edit: Oh my, since this March, I've bought 4 headphones, 1 headphone amp, 1 CD player, 1 outboard DAC, and now I'm thinking about getting another amp? I think I need help.
 
     Share This Post       
post-229571
Post #14 of 27

Jan Meier

King Corda
Member of the Trade: Meier Audio
Joined
Jun 21, 2001
Messages
831
Reaction score
111
Joined
Jun 21, 2001
Posts
831
Likes
111
Dear Gergor,

I hope to update my home-page today. Size of the HA-2 indeed is very similar to the HA-1. The new amp only has a thicker front-plate (8mm).

Jan
 
     Share This Post       
post-229572
Post #15 of 27

BenG

500+ Head-Fier
Joined
Jun 28, 2001
Messages
784
Reaction score
10
Joined
Jun 28, 2001
Posts
784
Likes
10
Quote:

Originally posted by Jan Meier
As whether sonic differences are to be expected from stacked buffers, please be aware that with both the PREHEAD and the HA-1 the buffers are placed within the feedback loop of a controlling opamp. It's the opamp that determines the quality of sound.


You mean HA-2, right?

Interesting news, on paper this is closer to where I originally thought your next amp after the HA-1 would be.
 
     Share This Post       

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top