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AUDIO FORUMS >> D.I.Y. >> ZKIT1 1st build
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Message started by meteor on 12/23/18 at 20:09:09

Title: ZKIT1 1st build
Post by meteor on 12/23/18 at 20:09:09

Hi,
I'm new to Decware and the forum. I own several tube amps and want to build 1 stereo or 2 mono ones. It would be nice to build a ZKIT1 and keep it made of 100% USA sourced parts.

I have a few questions that hopefully someone can help me with.

1. Is there a source for a decent enclosure for the amp or any suggestions for a DIY one?
I've looked at the KIT built pictures and the amps look great.

I have some basic soldering skills.
2. Is this a good amp to build as a beginner &
What is the difficulty level?

I'm not just looking for DIY - I also plan to buy a Decware made amp.

Thanks!
John

Title: Re: ZKIT1 1st build
Post by Lonely Raven on 12/25/18 at 19:06:09

I've not built a Z-kit, but I have one that someone started that I bought off them for the parts, and I've built several guitar amps from scratch over the years - so take this how you will.

Hammond does small enclosures that many amp builders use.

http://www.hammondmfg.com/scpg.htm

This is a great amp for beginner, because it's done on a circuit board and it's like a paint by numbers in assembly. Just put the parts in their place, solder correctly, trim the excess leads, and enjoy. There have been dozens of people who have made this amp in this forum as well as others - take some time and search through the forums for photos and suggestions, as well as Google and see what others have done for ideas.

Looking at the Transformers and parts that came with my (2nd hand Z-kit) it looks like it will sound just as good and probably better than my early SV83A amp. I think you'll really enjoy it and it's a great way to get into the flea watt SET amps!

Title: Re: ZKIT1 1st build
Post by meteor on 12/27/18 at 15:50:56

Hi Raven,

Thanks for the link to the enclosures and your insights on the build.
I bought one of the Hammond enclosures in a size that should work well with the amp.

To assemble the amp, I've purchased from 5 different sources for the parts.
The Edcor transformers are shown as being made to order and have a stated 8 week lead time. We'll see how that progresses.

All of the other listed parts were simple enough to order with just a couple needing substitutions because of not being in stock.

I'm looking forward to building a hand assembled USA made SET stereo tube amp!!

Thanks again!
John

Title: Re: ZKIT1 1st build
Post by Lonely Raven on 12/29/18 at 01:57:44

Awesome! Please post regular updates? I want to see how it goes for you.

~Eric~

Title: Re: ZKIT1 1st build
Post by benlefebvre on 01/11/19 at 13:44:08

My ZKIT amp sounds great. My advice would just to be to make sure your solder joints look good. I had problems with my initial build - voltages were all off and the tubes overheated - that were fixed after I redid some sloppy soldering.

For future reference, folks can also get all-metal cases at a company called Landfall Systems. No affiliation - just a happy customer. They’ll build the box to your measurements. I usually build my own wooden chassis and then order metal top plates.

Title: Re: ZKIT1 1st build
Post by kurt_b on 01/25/22 at 13:27:55

Hello everybody,
I`m new in this forum and I hope anyone could help me to get the my ZKIT1 amplifier kit working. First at all it was really "fun" to solder all parts to the board. This was some kind of meditative "work" for me I really could enjoy. I build two amps with the goal to bridge them into mono, but here is the problem.

Every time when I switch on the power of the amp, one of the 1k 6,5 watt resisters starts to smoke after 3-4 seconds. I'm sure this can´t be right, even when this resistors can get very hot. Both amplifiers behave the same. That is why I think/hope I made some (stupid) beginner mistake. My knowledge is (very) limited in understanding the specialty of the schematics. I checked already the soldering spots, correct parts and jumpers, but I could not find the mistake. I know how to build speakers and crossovers but this is my first amplifier kit project. So I feel a bit sorry for my unqualified question but I hope anyone has an idea for help.

Thank you for every suggestion
Kurt (from Germany)

Title: Re: ZKIT1 1st build
Post by kurt_b on 01/25/22 at 13:37:46

on this picture its the 1k resistor next to the blue capacitors.

Title: Re: ZKIT1 1st build
Post by kurt_b on 01/25/22 at 13:41:02

this tubes I have installed. There are the same like in the manual

Title: Re: ZKIT1 1st build
Post by kurt_b on 01/25/22 at 13:48:13

this is the output transformer. I don't know, but could it be that I made a mistake by connecting him correctly (black cables connected to the blue and brown power cable)? Also I connected the ground oft the power cable to the soldering spot "chassis ground". I hope this is correct, but I don't know.

Title: Re: ZKIT1 1st build
Post by BWC54 on 01/25/22 at 15:13:34

Looks like your output transformers are wired incorrectly. Why is Wht/Blue connected where red should be? Wht/Blue is a 40% tap which doesn't get used. It's hard to tell what is wired to what in that picture. A picture of the other side is required.

Also, since you mounted the volume control on the wrong side of the board, it should work backwards.

Title: Re: ZKIT1 1st build
Post by kurt_b on 01/25/22 at 17:10:31

Many thanks to your reply. I checked the wiring of the little output transformers again. I still can't find a mistake. All wires colors are at there described place. I made my test with one set of tubes. How can I know if they are working properly without having a possibility to measure them? Maybe they are faulty

Title: Re: ZKIT1 1st build
Post by kurt_b on 01/25/22 at 17:16:25

sorry the photo above was not very good...Is it a problem that i twisted the cables of the little transformers?

Title: Re: ZKIT1 1st build
Post by BWC54 on 01/25/22 at 17:31:03

Don't know why I didn't notice it in the first picture. Your tube sockets are on the wrong side of the board along with the volume control. Output transformers look ok. You don't need to wire the wht/blue.

Title: Re: ZKIT1 1st build
Post by kurt_b on 01/25/22 at 18:28:10

I'm really thankful for your help!! I will change the orientation of the tube sockets (stupid mistake) and the volume control. Than I will see.

Title: Re: ZKIT1 1st build
Post by BWC54 on 01/25/22 at 18:46:57

I don't know if I would trust that set of tubes. You might have damaged them by putting high voltage where it shouldn't be. Might be ok but I'd buy a new set for initial power up to be sure. If you still have a problem after changing the sockets and volume control I'd try new tubes.

Title: Re: ZKIT1 1st build
Post by kurt_b on 01/25/22 at 19:24:00

I changed the orientation of the sockets and the volume control. It looks like that the problem is gone :) It was only a short test but the overheating of the resistor is over. Thanks again for the help again!

Title: Re: ZKIT1 1st build
Post by kurt_b on 01/25/22 at 19:27:36

One stupid question again. To measure the voltage at the suggested points I go there with the tip of the voltmeter and although to the "ground chassi" point right?

Title: Re: ZKIT1 1st build
Post by Mannytheseacow on 01/27/22 at 02:49:38

Yes, touch your negative lead to the chassis ground. Good luck!