Layout 5th Generation 183

Overdrive Special, Steel String Singer, Dumbleland, Odyssey, Winterland, etc. -
Members Only

Moderators: pompeiisneaks, Colossal

Post Reply
User avatar
erwin_ve
Posts: 1792
Joined: Fri Jan 25, 2008 8:06 am
Location: Dordrecht, Netherlands
Contact:

Re: Layout 5th Generation 183

Post by erwin_ve »

nickm57 wrote:One question about the snubber values, they are rely low. Raw sounding amp? similar to no snubbers?
Yes I was thinking the same. These are really low snubbers, on the other hand; the resistor after coupling cap v2b is 180k so that should smooth things a bit. Edit: is 150k mmm...Edit again it is 180k :P
Last edited by erwin_ve on Thu Nov 11, 2010 8:32 am, edited 1 time in total.
dogears
Posts: 1902
Joined: Wed Feb 01, 2006 1:29 pm

Re: Layout 5th Generation 183

Post by dogears »

Not raw at all. The 250K OD pots take care of that, combined with the EL34 tubes. 250K pots add a considerable amount of miller effect.
erwin_ve wrote:
nickm57 wrote:One question about the snubber values, they are rely low. Raw sounding amp? similar to no snubbers?
Yes I was thinking the same. These are really low snubbers, on the other hand; the resistor after coupling cap v2b is 180k so that should smooth things a bit. Edit: is 150k mmm...
User avatar
erwin_ve
Posts: 1792
Joined: Fri Jan 25, 2008 8:06 am
Location: Dordrecht, Netherlands
Contact:

Re: Layout 5th Generation 183

Post by erwin_ve »

dogears wrote:Not raw at all. The 250K OD pots take care of that, combined with the EL34 tubes. 250K pots add a considerable amount of miller effect.
erwin_ve wrote:
nickm57 wrote:One question about the snubber values, they are rely low. Raw sounding amp? similar to no snubbers?
Yes I was thinking the same. These are really low snubbers, on the other hand; the resistor after coupling cap v2b is 180k so that should smooth things a bit. Edit: is 150k mmm...
Thanks Scott, that explains a lot! So a different load regulates the Miller effect?
User avatar
sergio
Posts: 405
Joined: Mon Nov 26, 2007 9:36 pm
Location: italy
Contact:

Re: Layout 5th Generation 183

Post by sergio »

Recently I found this:

http://www.banzaimusic.com/JJ-330uF-385V-radial.html

can be ok for a D-Amp?
jborders5
Posts: 171
Joined: Thu Oct 18, 2007 2:07 am
Location: Phoenix, AZ

Re: Layout 5th Generation 183

Post by jborders5 »

sergio wrote:Recently I found this:

http://www.banzaimusic.com/JJ-330uF-385V-radial.html

can be ok for a D-Amp?
Thanks for searching. The link shows an axial cap, but when you search the part on the JJ Electronics website the only option is a radial snap in.

http://www.jj-electronic.com/pdf/TC_TE.pdf
http://agbamplifiers.com/
Dumble Clone Circuit Boards
User avatar
Structo
Posts: 15446
Joined: Wed Oct 17, 2007 1:01 am
Location: Oregon

Re: Layout 5th Generation 183

Post by Structo »

AES has this JJ radial cap.

350uF @ 385v

[img:83:144]http://www.tubesandmore.com/cemirror/in ... 50-385.GIF[/img]

1-3/8" diameter x 3-1/2" long
Tom

Don't let that smoke out!
jborders5
Posts: 171
Joined: Thu Oct 18, 2007 2:07 am
Location: Phoenix, AZ

Re: Layout 5th Generation 183

Post by jborders5 »

ampdork wrote:The original had some such sideways thing going on.

I'd suggest mounting them standing up like the others in the ps.
I have the one leaked gut shot, but it doesn't show if the originals had radial leads, snap in or screw terminals. Anyway, it doesn't really matter since I don't care if the amp looks different than the original.

Orienting the caps standing up probably would be a cleaner & stronger way to mount them since you wouldn't need to rely on silicone as the primary means to secure them. There is enough room on a typical PPS board that it could be modified to work. I would think drilling (4) 1/8" eyelets and running jumpers under the board is the best option without producing a custom PCB. You would want to keep the caps diameter around 30MM and watch how tall it is depending the height of standoff used.

[img:800:679]http://img210.imageshack.us/img210/8872 ... inopt2.jpg[/img]
http://agbamplifiers.com/
Dumble Clone Circuit Boards
chris_sanford
Posts: 131
Joined: Wed Feb 14, 2007 6:47 pm
Location: Portland, OR

Re: Layout 5th Generation 183

Post by chris_sanford »

talbany wrote:
Shout out any errors you see..Enjoy!!

Tony
Leads from bass and mid caps should be reversed. Presence cap is .1uf? Probably should be 1uf as per usual. Also, I have never seen the Jazz/Rock switch wired that way (connection between treble side common and bass side lower pole).. doesn't mean it's not right, just thought I'd mention it.

chris
User avatar
Structo
Posts: 15446
Joined: Wed Oct 17, 2007 1:01 am
Location: Oregon

Re: Layout 5th Generation 183

Post by Structo »

Also the PAB relay is labeled mid boost.
Tom

Don't let that smoke out!
talbany
Posts: 4696
Joined: Tue Mar 28, 2006 5:03 am
Location: Dumbleland

Re: Layout 5th Generation 183

Post by talbany »

Tom/ Chris
THX REV 4 up..Chris on the R/J.. I thought so too.. AFAIK the RJ switch is correct..If you want to trace it back figure out how it functions differently than that of the standard that would be great.. If you do this and find any errors I'll be glad to change the layout..THX

Tony
" The psychics on my bench is the same as Dumble'"
User avatar
Structo
Posts: 15446
Joined: Wed Oct 17, 2007 1:01 am
Location: Oregon

Re: Layout 5th Generation 183

Post by Structo »

Tony, first of all, thank you for all your hard work.
I know how tedious these layouts can be and how much work they are.

I was wondering if there was a better way to show that PAB relay, to show the way the traces are laid out?
Maybe use the #124 type graphic so you can manipulate the traces.

I know that the leads are on the normally connected contacts but for others not familiar with the way the relays work it would help if you could see the traces.

This amp is different in that it has both 22M resistors on the relay board instead of one 22M on the treble pot like #124.

Thanks!
Tom

Don't let that smoke out!
talbany
Posts: 4696
Joined: Tue Mar 28, 2006 5:03 am
Location: Dumbleland

Re: Layout 5th Generation 183

Post by talbany »

Structo wrote:Tony, first of all, thank you for all your hard work.
I know how tedious these layouts can be and how much work they are.

I was wondering if there was a better way to show that PAB relay, to show the way the traces are laid out?
Maybe use the #124 type graphic so you can manipulate the traces.

I know that the leads are on the normally connected contacts but for others not familiar with the way the relays work it would help if you could see the traces.

This amp is different in that it has both 22M resistors on the relay board instead of one 22M on the treble pot like #124.

Thanks!
Tom
Sure be glad to do that.
THX... Tony
" The psychics on my bench is the same as Dumble'"
jborders5
Posts: 171
Joined: Thu Oct 18, 2007 2:07 am
Location: Phoenix, AZ

Re: Layout 5th Generation 183

Post by jborders5 »

Structo wrote: I was wondering if there was a better way to show that PAB relay, to show the way the traces are laid out?
Maybe use the #124 type graphic so you can manipulate the traces.

I know that the leads are on the normally connected contacts but for others not familiar with the way the relays work it would help if you could see the traces.
Tony- Here are a couple of relay options with traces if it helps. You may need to play with the transparency on the green board option when printing or converting to a .jpg.
You do not have the required permissions to view the files attached to this post.
http://agbamplifiers.com/
Dumble Clone Circuit Boards
talbany
Posts: 4696
Joined: Tue Mar 28, 2006 5:03 am
Location: Dumbleland

Re: Layout 5th Generation 183

Post by talbany »

Jason
Thanks for the offer but just finished rev6..Hey how about giving me some lessons on Visio.. Your layouts are wonderful!!

Tony
Last edited by talbany on Thu Nov 11, 2010 5:22 pm, edited 1 time in total.
" The psychics on my bench is the same as Dumble'"
User avatar
ChrisM
Posts: 1169
Joined: Wed Oct 22, 2008 11:12 pm
Location: Toronto, Canada.

Re: Layout 5th Generation 183

Post by ChrisM »

Tony, you do not need lessons on Visio!!!
:D
Post Reply