Search found 378 matches
- Sun Apr 09, 2023 1:43 pm
- Forum: Dumble Files
- Topic: Ultraphonix adventure
- Replies: 200
- Views: 238756
Re: Ultraphonix adventure
im worn out please accept my sloppy clips ive been writing terrifying jokes for 40 hours https://www.dropbox.com/s/b7krctki168811z/sibly.MOV?dl=0 https://www.dropbox.com/s/x6kb17b4crv28hv/wcm.MOV?dl=0 Love it! Which version, in this thread, are these clips made from? Is it the schematic that Bepone...
- Fri Mar 31, 2023 4:12 pm
- Forum: Technical Discussion
- Topic: HEX Electrics 300X
- Replies: 12
- Views: 1684
Re: HEX Electrics 300X
I'm puzzled as well. How would a UL primary drop the screen voltage?
- Fri Mar 17, 2023 5:58 pm
- Forum: Technical Discussion
- Topic: 6L6 Cathode biased advice / ideas
- Replies: 13
- Views: 1665
Re: 6L6 Cathode biased advice / ideas
If you want to try something a little different, try a combination of Fixed/Cathode. Size the cathode resistor for 15-20 % of what you would typically use for a common cathode resistor and generate the rest of the bias with the fixed bias circuit. Do not bypass the common cathode resistor - it will ...
- Fri Jan 27, 2023 7:18 pm
- Forum: Dumble Files
- Topic: Ultraphonix adventure
- Replies: 200
- Views: 238756
Re: Ultraphonix adventure
here is the schematic, missing first gain 1MA V1 gain stage, 180k/2k7, second half 130k/1k8 V2 CF: 150k/1k8, cathode follower 82k cathode (intended compression, not like "normal" 100k/100k) sema.jpg Is the hand drawn schematic pretty much what you ended up with? I have a donor amp I may try this on.
- Mon Jan 09, 2023 4:16 pm
- Forum: Technical Discussion
- Topic: Octal preamp 2204 build questions
- Replies: 25
- Views: 11101
Re: Octal preamp 2204 build questions
Cool chassis design. Did you fabricate it yourself?
Bruce Clement, BC Audio, makes a lot of octal Marshall style amps. He typically does DC heaters on the 6SL7's to keep the noise down.
Bruce Clement, BC Audio, makes a lot of octal Marshall style amps. He typically does DC heaters on the 6SL7's to keep the noise down.
- Sun Oct 30, 2022 1:37 pm
- Forum: Garage Talk
- Topic: Where does tone come from in a guitar?
- Replies: 34
- Views: 4468
Re: Where does tone come from in a guitar?
That created a slightly disturbing visual that I can't un-seeReeltarded wrote: ↑Sun Oct 30, 2022 4:31 am Granted, it feels more like knowledge than a girl licking a wind sock and whispering the contents of her purse.
- Wed Sep 21, 2022 9:54 pm
- Forum: Marshall Discussion
- Topic: JTM45 style amp with KT66's can't run 6L6's?
- Replies: 40
- Views: 8757
Re: JTM45 style amp with KT66's can't run 6L6's?
So on the standard JTM45 w/KT66 -> 8k Prim, would it be a good mod to remove the 470K screen grids and replace with 1K or 1.5K to better protect the screens? Might add a little squish to the PA?
- Tue Sep 20, 2022 12:56 am
- Forum: Marshall Discussion
- Topic: JTM45 style amp with KT66's can't run 6L6's?
- Replies: 40
- Views: 8757
Re: JTM45 style amp with KT66's can't run 6L6's?
When the load line crosses the Vg1=0 line far below the knee (as it does when the primary impedance is too high), it takes less Vg1 voltage swing to reach the point where the screen current shoots up, and it's much more likely that the screens will be over-stressed. This would only be of concern wh...
- Mon Sep 05, 2022 7:22 pm
- Forum: Marshall Discussion
- Topic: JTM45 style amp with KT66's can't run 6L6's?
- Replies: 40
- Views: 8757
Re: JTM45 style amp with KT66's can't run 6L6's?
EL34 plate loading is around 3400 ohms, while it's around 8000 for KT66s. Optimally you'd obtain a new output transformer that's wound for KT66s but using the next higher impedance tap on the speaker jacks is a perfectly good workaround. KT66 are not much different from 6L6, and would really like a...
- Sun Aug 07, 2022 10:28 pm
- Forum: Garage Talk
- Topic: Two Rock Studio at my local pub
- Replies: 1
- Views: 1403
Two Rock Studio at my local pub
A local pub that's about a mile from my house has live music every Saturday night - typically cover bands that mostly appeal to Gen X'ers. Many of the guitarists are favoring smaller/lighter rigs ranging from small combos, floor modelers, pedal board amps, etc and most produce a pretty decent sound ...
- Mon Mar 14, 2022 11:12 am
- Forum: Technical Discussion
- Topic: Variac before or after Furman PF Pro.
- Replies: 5
- Views: 842
- Thu Mar 10, 2022 12:22 pm
- Forum: Marshall Discussion
- Topic: JTM45 style amp with KT66's can't run 6L6's?
- Replies: 40
- Views: 8757
Re: JTM45 style amp with KT66's can't run 6L6's?
Yep, the schematic above is for a RT66.
Antidote is based on JTM45.
From the Dr himself:
https://www.youtube.com/watch?v=PsymtzV7Jhg
Antidote is based on JTM45.
From the Dr himself:
https://www.youtube.com/watch?v=PsymtzV7Jhg
- Mon Mar 07, 2022 6:39 pm
- Forum: Marshall Discussion
- Topic: JTM45 transformer selection for 5881s
- Replies: 16
- Views: 3419
Re: JTM45 transformer selection for 5881s
I had a discussion with tech support at Tube Depot, specifically about the new production Tung-Sol 5881's. I wanted to put them in an amp with a 500vdc B+, he cautioned against it - stating that they would likely have a greatly reduced lifespan.
- Mon Mar 07, 2022 12:14 pm
- Forum: Technical Discussion
- Topic: full feature low watt amp
- Replies: 4
- Views: 976
Re: full feature low watt amp
Why not build a higher powered amp with power scaling? Then you have one amp that covers at home/studio and gig volumes.
5W is still pretty loud
5W is still pretty loud
- Sun Mar 06, 2022 11:59 am
- Forum: Marshall Discussion
- Topic: JTM45 transformer selection for 5881s
- Replies: 16
- Views: 3419
Re: JTM45 transformer selection for 5881s
Be careful with the plate voltages on 5881's, I think they're only rated for 400v.