Corda HA-1 as a DIY kit?
May 9, 2002 at 1:00 AM Post #2 of 14

davo

Head-Fier
Joined
Mar 18, 2002
Posts
80
Likes
0
Good question as I'm interested in doing this as well.

I have two further questions for the collective.

1. What power cord would you folks suggest?
2. What source to amp cable would you recommend (and what is the configuration...rca to rca?

Thanks in advance.
 
May 9, 2002 at 1:14 AM Post #3 of 14

chych

The butter knife's second victim.
Joined
Jun 21, 2001
Posts
1,985
Likes
13
HD5000, I hear the Corda is more for, non beginners... wouldn't try building it without much experience.

davo, that depends on your price range really... and a lot of us cannot tell differences in power cords...
 
May 9, 2002 at 8:28 AM Post #4 of 14

tangent

Top Mall-Fi poster. The T in META42.
Formerly with Tangentsoft Parts Store
Joined
Sep 27, 2001
Posts
5,969
Likes
56
The Corda was the very first DIY kind of thing I ever did. It took the advertised 5 hours to put together, except for the troubleshooting I had to do because of a few cold solder joints. If you're experienced, you don't make cold joints, so I suppose it is helpful to have some experience. It's just not essential, that's all I'm saying.

What you do need:

1) A good soldering iron. No Rat Shack junk. Get something with a nice, fine tip that will stand up to serious work.

2) A multimeter, or a lot of patience. The resistors are shipped unlabeled, so you either need to measure them or read the stripe codes.

3) Small screw drivers (standard and Philips), pliers, etc. Also, 2mm and 2.5mm hex keys (a.k.a. Allen wrenches).

4) A basic knowledge of how to read a schematic. If you don't know how, there's a book you can get at Radio Shack, "Electronc Formulas, Symbols and Circuits" which will tell you everything you need to know.

5) The instructions are pretty sparse and yet exacting. If you plug the wrong part into the wrong hole, you can destroy the amp. If you can follow instructions, you won't have problems. I sent Jan Meier a lot of commentary after building my amp. If some of that made it into the documentation he sends with the kit, you will have an easier time of it than I did. The main problem is that the capacitors aren't labeled (not so I could understand them, anyway) and so without a capacitance meter you have to just gather the caps that are of the same kind, count them, and then count the caps on the layout diagram to find out which set is which value. If Jan's documentation is now clearer, you won't have to worry about this issue. I suppose you could also study the pictures of populated boards on his web site -- they may have enough detail that you can figure issues like this out.

The Corda HA-1 is a fine amp. If you are suited to the task, building one from a kit is very educational and interesting. It makes you feel more connected with the amp when it's done. It's a part of you, not just something you bought from a hi-fi shop.

It's also a great introduction to DIY. You will know, after building this kit, whether you want to try building something from scratch or not.
 
May 9, 2002 at 2:14 PM Post #5 of 14

davo

Head-Fier
Joined
Mar 18, 2002
Posts
80
Likes
0
Tangent,

Thanks for your inputs and caveats. While it hasn't put me off from undertaking either this or possibly some other kit, I'll be sure to take my time and be a careful as I can and mind your suggestions.

I have soldering experience so all I'll need is a good soldering iron. I think I've got the rest of the required tools.

Thanks again for sharing your experiences.
 
May 9, 2002 at 3:37 PM Post #6 of 14

ponzio

That strange guy readingover your shoulder
Joined
Jul 6, 2001
Posts
114
Likes
10
Tangent is right, the most difficult part is sorting out the components. The instructions could be presented more clearly, but generally contain everything you need to know. The Corda was my first DIY electronic kit, and I'm glad I did it.
 
May 9, 2002 at 6:29 PM Post #7 of 14

tangent

Top Mall-Fi poster. The T in META42.
Formerly with Tangentsoft Parts Store
Joined
Sep 27, 2001
Posts
5,969
Likes
56
Please re-read my post above. I remembered some things right after I wrote it, but just then Head-Fi's database went mad so I couldn't update the article. I just barely sent in the changes.
 
May 9, 2002 at 7:40 PM Post #8 of 14

davo

Head-Fier
Joined
Mar 18, 2002
Posts
80
Likes
0
Tangent,

Not quite sure of your intent. I have re-read your post and see no changes, at least that I can recognize.

Am I missing something (not unusual for me)?

Thanks-
 
May 9, 2002 at 8:02 PM Post #9 of 14

tangent

Top Mall-Fi poster. The T in META42.
Formerly with Tangentsoft Parts Store
Joined
Sep 27, 2001
Posts
5,969
Likes
56
I added item 3, and I clarified the issue that confused me most about the assembly process. I went back and re-read my email to Jan Meier, which made me realize my previous post was...lacking.
 
May 9, 2002 at 10:05 PM Post #12 of 14

markjia

100+ Head-Fier
Joined
Nov 2, 2001
Posts
217
Likes
0
HD5000,

I wouldn't say so. I built the morgan jones diy tube amp using a rat shack soldering iron without much trouble. But if you end up having problems, just get a better one...they're not that expensive.
 
May 9, 2002 at 10:18 PM Post #13 of 14

Nick Dangerous

Mr. Tuberrific
Joined
Nov 19, 2001
Posts
2,623
Likes
27
Find yourself a Weller or Hakko soldering iron. Quality stuff. 25 to 35 watts should be enough.

Also get one of those "third helper hands" from Radio Shack for $9. Take off the silly magnifying glass and you're set.
 
May 10, 2002 at 4:52 AM Post #14 of 14

tangent

Top Mall-Fi poster. The T in META42.
Formerly with Tangentsoft Parts Store
Joined
Sep 27, 2001
Posts
5,969
Likes
56
Before I explain my beef with Radio Shack irons, let me point out that since I was burned by them (not literally), I haven't tried them again. I suppose something could have changed in the past, oh, 8-10 years I've been using other irons.

The last time I used an RS iron, it had this big crude tip that had a broader taper than a sharpened pencil. As I recall, the tip was a simple 1/8" diameter shaft with a 45 degree taper to it. That's completely unsuitable for delicate electronics work. But worse than that, it wouldn't hold solder well at all, and after enough heating/cooling cycles from cleaning the tip on a damp sponge, the tip literally cracked and shattered!

Since then, for pencil irons I've been using the $10 irons I can get at a local independent electronics shop. They're no-name irons, and the price is the same as Radio Shack's typical stuff, but the tips are replaceable, they have decent tapers, they hold solder well, and they stand up to normal use. Radio Shack irons seem designed solely for trivial tasks like tinning a few speaker wires and then being put back in the drawer for another few years, waiting for the next odd job.

I've also been using a soldering station, but I don't expect every DIYer to go out and buy one of those. They sure can spoil a guy, though.
smily_headphones1.gif


EDIT: Oh yes, and Nick's spot on: helping hands are great, and the magnifying glass is indeed silly and should be removed ASAP. After that, it's a better tool for most electronics work than even the vaunted Panavise, IMHO. Cheaper, too. Caveat: the alligator clips aren't brazed to the little arms, they're just crimped on. I've had to do an amateur brazing job on one of them when it broke, but since then it's given me no trouble. I just heated it up with the soldering iron set as high as it would go and once it started accepting solder I just poured a bunch in the cracks. It holds up well now. A proper brazing job would have worked better, though.
 

Users who are viewing this thread

Top