Developing the DIY "Champ" for first time builders

[xtian]

Build coming along. I'll finish this weekend. Sprayed the chassis with Rust-Oleum Hammered spray paint. I LOVE how the Edcor trannies look! I'm naming this one Blue Meanie. I'll have some vinyl cut at Kinkos.

[xtian]

OK for input and output jacks to be grounded to chassis? In some builds I've used insulated output jacks so it doesn't touch the chassis.

[RJ Guitars]

I used to insulate them 100% which was what my HiFI tube Guru mentors taught me. However, I've found that guitar amp community doesn't seem to be overwhelmingly concerned with that practice. Since this is not a high gain amp there is no reason unless you have your personal technical reasons otherwise. This is typical for the Trainwreck builds including all the high gain models.

rj

[vntg]

I'm new here and a real amp noob. I have some electronics background from my airplane mechanic training. This thread brought me here via a link.
This looks like a good first project for me.
Can these be expanded at a later date? The idea being to experiment with a tone stack and MV. Maybe later go with a KT88 or 6L6GT tube?
I'd like to get my feet wet before attempting to build my dream amp which would be a 5E3 (kinda) with 6L6GT's, a multi tap OT and a 'verb.

[RJ Guitars]

I'm new here and a real amp noob. I have some electronics background from my airplane mechanic training. This thread brought me here via a link.
This looks like a good first project for me.
Can these be expanded at a later date? The idea being to experiment with a tone stack and MV. Maybe later go with a KT88 or 6L6GT tube?
I'd like to get my feet wet before attempting to build my dream amp which would be a 5E3 (kinda) with 6L6GT's, a multi tap OT and a 'verb.

vntg,

Your thoughts are well aligned with where we have taken this thread. There have been three iterations of this project emerge: Basic, Premium, and Supre. What you have described in your experimental amp is the Supre. Let me know if you's like to join in this effort. For the first round of any iteration we develop here on TAG I attempt to supply the parts for that build within a few dollars of cost... sometimes I win sometimes I loose. Read back with an eye toward the Supre build and see if that suits you. The chatter that is going around now would lead us from the Supre toward the DLM, if we only knew what that was?

rj

[xtian]

For the premium kit with Edcor trannies, I need suggestions on where to ground the center taps for the 6.3vac heater supply and the high voltage pair.

RJ, am I correct that you have not yet posted a layout for the Premium kit?

Sorry, one more thing: on your layouts, the in and out jacks look incorrectly wired. The lug furthest away from the entrance of the jack is the ground, at least on these switchcraft jacks. But you show this wired as if it were the tip (signal).

[surfsup]

For the premium kit with Edcor trannies, I need suggestions on where to ground the center taps for the 6.3vac heater supply and the high voltage pair.

Can you ground 'em at the IEC mains ground lug?

[xtian]

Yes, but for the heater center tap, sometimes you get good results connecting to the power tube cathode (right?) to raise the reference voltage.

[surfsup]

yes, I believe you can do that. I did that with my HO at first, but ended up building a 46V elevation circuit and tying the ground to one of the rail caps. But, ultimately that didn't help either. My hum problem turned out to be the ground rail design, so not sure how much tying the ground to a cathode helps since I've never experienced the benefits of doing that.

RJ's layout already has a similar ground design (well on the regular build) where the ground lines are individually starred and each runs to the main star ground at chassis, so I wouldn't think it would matter much if you chose either location, but I'm no expert!

[RJ Guitars]

OK - here is a first drawing. I was thinking that I could skate the Basic drawing through for the Premium. But if you consider that the thought was to create this for first time builders, they don't need the confusion.

This is the very early rough copy and as you can see each one is derived from the previous. If I had better version control you wouldn't see any of the early errors propagate, but that isn't always the case. .. but no excuses, the plan is to have each set of drawings complete and if you watch the rev #'s, you shouldn't get caught working from an old copy.

As always, I am not offended but appreciative if you find an error and point it out.

Note many of the changes were driven by your input... I like this amp a lot.

thanks,

rj

edit 3/27 - layout revved - subtle but important changes to the input and output jacks

[M Fowler]

After wrestling with marking, fitting and drilling holes in the cabinet I finally got the little bastard amp done!

Nice sounding and I like having the tone controls. Showed it to my grandson and he was happy but way too young yet to concentrate on guitar lessions

Mark

[surfsup]

http://www.russiantubes.com/prop.php?t=12&p=241

Found a 6p6s pinout here, hope it helps someone...

[RJ Guitars]

After wrestling with marking, fitting and drilling holes in the cabinet I finally got the little bastard amp done!

Nice sounding and I like having the tone controls. Showed it to my grandson and he was happy but way too young yet to concentrate on guitar lessions

Mark

- Cool! Sounds like thoroughly enjoyed the experience... Maybe you'll include your grandson in some of the photos? Looking forward to your pictures and audio clips. Did you use the tone stack like I made up for the Supre or something different?

[M Fowler]

rj I used the layout from Triode but you can see the differences can cap verse I used 22uf-8uf-8uf caps. I didn't use a standby switch either. Mine is single input and single speaker jack.

I used your board just pulled out some turrets and add more where I needed them.

Mark

[RJ Guitars]

http://www.russiantubes.com/prop.php?t=12&p=241

Found a 6p6s pinout here, hope it helps someone...

Great! That will be handy. The 6P6S pinout should be identical to the 6V6GT. They don't take the voltages that 6V6GT will but in these amps they are a good fit. I swap them back and forth in my Basic amp.

BTW - I had the 6N6C listed on the Eagle Basic layouts and I changed that to 6SPS on the Premium because that is what most of them are listed under on EBAY. Also when ordering these i had a real tendency to mix it up with the 6H6N (a dual triode) which I now have an extra dozen looking for a future project.

rj