2203... Effects Loop
Moderators: pompeiisneaks, Colossal
Re: 2203... Effects Loop
(deleted)
Last edited by matt h on Fri Mar 27, 2015 2:41 pm, edited 1 time in total.
Re: 2203... Effects Loop
Yup we should have our own TAG board and I am willing to help sponsor.
Mark
Mark
Re: 2203... Effects Loop
I remember your post on Metro forum about that. Copied the Lerxst circuit too from Steve's layout.Reeltarded wrote:The Mojo SS loop board already ripped Steve off.
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dorrisant
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Re: 2203... Effects Loop
Deric, is that one that you built? Looks like two boards there... Right?
I wonder how much it loads the preamp. Is the input impedance very high?
I wonder how much it loads the preamp. Is the input impedance very high?
"Education is what you're left with after you have forgotten what you have learned" - Enzo
Re: 2203... Effects Loop
Has anyone tried building an fx loop with MOSFETs .
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dorrisant
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Re: 2203... Effects Loop
Matt, I pmed you back.
Cbass, K O'Conner suggests a cascode design using a j-fet input and a mosfet regulator as the output of a buffer stage. The j-fet has tubelike input impedance but has poor output impedance. The mosfet has the output impedance needed. This combo is supposed to be the best of both worlds. I don't know about the others... Yet
Looks like Deric's design above uses them.
Tony
Cbass, K O'Conner suggests a cascode design using a j-fet input and a mosfet regulator as the output of a buffer stage. The j-fet has tubelike input impedance but has poor output impedance. The mosfet has the output impedance needed. This combo is supposed to be the best of both worlds. I don't know about the others... Yet
Looks like Deric's design above uses them.Tony
"Education is what you're left with after you have forgotten what you have learned" - Enzo
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JazzGuitarGimp
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Re: 2203... Effects Loop
I'd be happy to donate my time to do a pcb layout for the TAG Loop Board.
Lou Rossi Designs
Printed Circuit Design & Layout,
and Schematic Capture
Printed Circuit Design & Layout,
and Schematic Capture
Re: 2203... Effects Loop
(deleted)
Last edited by matt h on Fri Mar 27, 2015 2:40 pm, edited 1 time in total.
![[IMG:160:101]http://i40.photobucket.com/albums/e243/stumper1/DC%20Rocket/th_DCRocket_zps9e366a60.jpg[/img]](http://s40.photobucket.com/user/stumper1/media/DC%20Rocket/DCRocket_zps9e366a60.jpg.html){kind=link}
![[IMG:160:120]http://i40.photobucket.com/albums/e243/stumper1/DC%20Rocket/th_DCRocket014_zps91541dd1.jpg[/img]](http://s40.photobucket.com/user/stumper1/media/DC%20Rocket/DCRocket014_zps91541dd1.jpg.html){kind=link}
Re: 2203... Effects Loop
I'd invest in this, sure thing. Gonna be needing one for an upcoming build, and I'd rather not have to tweak the design as it is now, because it does need tweaking. And it's another tube. Not that I don't like tubes, mind you. The whole friggen amp it'll go in needs tweaking, and that's being modest... 
Yeah, I'm down with a "transparent" TAG effort loop! I'd love to say I can help more than monetarily, but, ya know.. Derpderp.
Yeah, I'm down with a "transparent" TAG effort loop! I'd love to say I can help more than monetarily, but, ya know.. Derpderp.
Re: 2203... Effects Loop
Yes, that is one I built. Yep - 2 boards. The bottom board is just a shield - a 2 layer board with the bottom as a ground plane would probably work great. This was just my low-tech solution. It has a switch that bypasses the loop completely so you can A/B it very easily. Sounds (and feels) the same either way.dorrisant wrote:Deric, is that one that you built? Looks like two boards there... Right?
I wonder how much it loads the preamp. Is the input impedance very high?
Last edited by Deric on Sun Dec 07, 2014 11:52 pm, edited 1 time in total.
Deric®
Re: 2203... Effects Loop
For the record....not my "design". Just a direct rip-off of one of the loops being discussed here. The PCB layout is my design but VERY much "inspired" by the original.dorrisant wrote: Looks like Deric's design above uses them.
Tony
Deric®
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dorrisant
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Re: 2203... Effects Loop
I agree with what Matt said... I don't want to make a fortune. I just want to be able to source a flexible loop design that does all the things the installer wants from it, like:
1) installing trimpots for level controls or mount them in them the back panel for external adjustment.
2) option for relay or switch controlled true bypass. This way a switch could be panel mounted or the bypass could be footswitch controled via relay.
3) mounting holes for the board to be standoff mounted. This would allow more flexibility for mounting... Switchcrafts or Cliffs could be wired in.
4) The key feature would be the high voltage input capability. It would be good to have the signal swing take up no more than 60% of the available signal window for the best linearity.
I have no doubt that Lou would do a much nicer layout in a shorter amount of time... I would gladly take a step back here. I would offer to do assembly and testing if is necessary. Overall I want to provide a PCB and parts kit maybe even offer assembled boards, whatever level the buyer is comfortable with. I just see a need and want to push forward with an offering that the people here at TAG can take advantage of. This could be a drop in solution much like VVR.
I'm sure there are some features or options that need to be addressed... ?
Tony
1) installing trimpots for level controls or mount them in them the back panel for external adjustment.
2) option for relay or switch controlled true bypass. This way a switch could be panel mounted or the bypass could be footswitch controled via relay.
3) mounting holes for the board to be standoff mounted. This would allow more flexibility for mounting... Switchcrafts or Cliffs could be wired in.
4) The key feature would be the high voltage input capability. It would be good to have the signal swing take up no more than 60% of the available signal window for the best linearity.
I have no doubt that Lou would do a much nicer layout in a shorter amount of time... I would gladly take a step back here. I would offer to do assembly and testing if is necessary. Overall I want to provide a PCB and parts kit maybe even offer assembled boards, whatever level the buyer is comfortable with. I just see a need and want to push forward with an offering that the people here at TAG can take advantage of. This could be a drop in solution much like VVR.
I'm sure there are some features or options that need to be addressed... ?
Tony
"Education is what you're left with after you have forgotten what you have learned" - Enzo
Re: 2203... Effects Loop
I am wondering given the CF in the 2204 and the tone stack off the cathode, whether it is really necessary to have a solid state buffer and not just a solid stage return stage for the FX?
I have built a Marshall style preamp with a full D'Lator on board and just the return gain stage of the FX. I can NOT tell any negative tonal differences with just the return gain stage. I did it both ways with the same amp.
with respect, 10thtx.
I have built a Marshall style preamp with a full D'Lator on board and just the return gain stage of the FX. I can NOT tell any negative tonal differences with just the return gain stage. I did it both ways with the same amp.
with respect, 10thtx.
Re: 2203... Effects Loop
Why? compartmentalization.
From the amp's standpoint, whatever you throw in the loop isn't going to change the loading on the cf/tonestack. consistency is good.
from the stuff in the loop's perspective: you can tailor the signal out of the send for pedal or rack gear to prevent inputs from clipping. similarly: consistent (whether high or low maybe not as important) impedance and signal.
at least my quick reasoning. obviously, any loop is the worst thing in the world. but if you gotta (absolutely have to) have one, ways to make it more useful under more conditions. One man's pedals might not care. One man's rack gear might not care. Another man's everything might care.
From the amp's standpoint, whatever you throw in the loop isn't going to change the loading on the cf/tonestack. consistency is good.
from the stuff in the loop's perspective: you can tailor the signal out of the send for pedal or rack gear to prevent inputs from clipping. similarly: consistent (whether high or low maybe not as important) impedance and signal.
at least my quick reasoning. obviously, any loop is the worst thing in the world. but if you gotta (absolutely have to) have one, ways to make it more useful under more conditions. One man's pedals might not care. One man's rack gear might not care. Another man's everything might care.