Swamper amp project
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- guitardude57
- Posts: 355
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Re: Swamper amp project
Pretty cool amp Mark!
Cathode biasing makes things a little more forgiving, and keeps the volume somewhat more manageable, (especially if you don't have a master volume) on those big bottles.
My first (Testing - Proto chassis) Express circuit uses Cathode Bias on 6L6gc/5881 type, and love it. Helps keep the paint on the walls and the Border Collies from howling!
Cathode biasing makes things a little more forgiving, and keeps the volume somewhat more manageable, (especially if you don't have a master volume) on those big bottles.
My first (Testing - Proto chassis) Express circuit uses Cathode Bias on 6L6gc/5881 type, and love it. Helps keep the paint on the walls and the Border Collies from howling!
Mike
I am never surprised and always amazed
I am never surprised and always amazed
Re: Swamper amp project
Thanks I changed the screens from 470R to 1k/5w tonight.
I think I will change the amp to adjustable fixed bias being I have a bias tap on this PT. I would like to hear the difference. Also maybe change it to switched SS recto/tube recto.
It does have a master volume so I can tune it down for stage volume.
Had previously played around with different plate load resistors on V1a&b as well as different bias cap/resistors values. Even tried three different types of caps there as well. Right now I backed the gain down to more reasonable level.
Its really looking ratty with all the unsoldering and changes.
I find it best with JJ/6L6 rather than EL34.
Mark
I think I will change the amp to adjustable fixed bias being I have a bias tap on this PT. I would like to hear the difference. Also maybe change it to switched SS recto/tube recto.
It does have a master volume so I can tune it down for stage volume.
Had previously played around with different plate load resistors on V1a&b as well as different bias cap/resistors values. Even tried three different types of caps there as well. Right now I backed the gain down to more reasonable level.
Its really looking ratty with all the unsoldering and changes.
I find it best with JJ/6L6 rather than EL34.
Mark
Re: Swamper amp project
Lastest version of the Swamper amp.
Suppose to be sunny tomorrow maybe I can find a better backdrop and take better pictures.
Suppose to be sunny tomorrow maybe I can find a better backdrop and take better pictures.
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- RJ Guitars
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Re: Swamper amp project
Nice work Mark! I think it is only fitting that something called a "Swamper" amp has a snake skin covering.
Sunny in Minnesota in January may be good light for photos shoots but I heard the wind chill there today was -36F... forget those "cryo" cured tubes... we should just send a few of the regular ones to you and you could put them out on the back porch for a day or two.
Sunny in Minnesota in January may be good light for photos shoots but I heard the wind chill there today was -36F... forget those "cryo" cured tubes... we should just send a few of the regular ones to you and you could put them out on the back porch for a day or two.
Last edited by RJ Guitars on Fri Jan 24, 2014 4:42 am, edited 1 time in total.
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- JazzGuitarGimp
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Re: Swamper amp project
That's a good looking' amp, Mark! Are the first two controls volume? How are they arranged?
edit: Oops, sorry, I didn't see you had posted a schematic on page 1.
edit: Oops, sorry, I didn't see you had posted a schematic on page 1.
Lou Rossi Designs
Printed Circuit Design & Layout,
and Schematic Capture
Printed Circuit Design & Layout,
and Schematic Capture
Re: Swamper amp project
Thanks guys, it was either snake or alligator for the swamp look.
Now you know why I don't have tube problems rj, my secret cryo tubes.
Some values have changed on the schematic and this one is fixed bias.
Colossal has offered to make an updated schematic so I will get on that.
Mark
Now you know why I don't have tube problems rj, my secret cryo tubes.
Some values have changed on the schematic and this one is fixed bias.
Colossal has offered to make an updated schematic so I will get on that.
Mark
Re: Swamper amp project
Looks great Mark.
Sounds like you have refined the design and it is performing well.
Sounds like you have refined the design and it is performing well.
Tom
Don't let that smoke out!
Don't let that smoke out!
Re: Swamper amp project
Thanks Tom there is always room for improvement but this circuit has been local guitar players approved
Re: Swamper amp project
This is using a Mojotone BF Bassman chassis so I had to get the faceplate to work with the existing pot holes so this is what I came up with working with mojo's faceplate guy. I think he did a great job with the plate.
The cabinet is mojotone and currently speaker is WGS G12 C/S-75w American bite.
Mark
The cabinet is mojotone and currently speaker is WGS G12 C/S-75w American bite.
Mark
- randalp3000
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Re: Swamper amp project
Looks great Mark, of course. Have you ever tried it without the Cathode follower and tone stack?
Re: Swamper amp project
No I wasn't looking to experiment on this circuit I've have many other amps I can play around with.
Re: Swamper amp project
My early Swamper amp http://ampgarage.com/forum/download/fil ... &mode=view has changed hands a few times but keeps on Rocking Fargo ND area these young guys are keeping Rock alive thankfully. New tubes (Cathode bias). A year ago I put in a new mid pot 250k, added presence and resonance on the back panel. Cheaply built amp but sounds great. Channing guy on strat with rag hanging off head stock/singer in a band called the Knotties.
https://www.youtube.com/watch?v=2XWju7qBJZc
https://www.youtube.com/watch?v=AsaV6FNt_og
https://www.youtube.com/watch?v=2XWju7qBJZc
https://www.youtube.com/watch?v=AsaV6FNt_og
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Re: Swamper amp project
Nice sounding amp
Re: Swamper amp project
Thanks, it's hard to get good sounding video but in person the amp has tone qualities I like.
He thinks it's too bright which I could reduce the mid pot the previous owner had me add for more mid range and that Strat doesn't help with it's lip stick pups.
He thinks it's too bright which I could reduce the mid pot the previous owner had me add for more mid range and that Strat doesn't help with it's lip stick pups.