Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Mike_J on January 31, 2016, 07:46:16 am
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I have been tinkering with the MS-Visio software that was installed on my computer the other day. Doing a mock-up of the Deluxe Reverb - One Channel with passive FX and PPIMV. Came to a terrifying revelation.
It does appear that changing from Fender to Marshall style, tubes down versus tubes up, creates some complexity if keeping the left to right Fender front panel layout is deemed preferable. Going left to right means turning the pots upside down and running into the b side of the preamp tubes first. This means the bypass cap and resistor would start out on the inside and the tone caps,etc. would be on the outside. An entirely new layout would be required.
I am starting to lean towards going right to left with the front panel layout. Will need to have a new faceplate made either way because I want to get the wires to and from the PPIMV pot as short as possible. Anyone else have any experience or suggestions concerning this matter?
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I do all my layouts with tubes across the bottom, pots across the top with input jack(s) on the top right. My layout matches the bottom view of an amp with knobs pointed away from you. Fender is the same as Marshall. I started doing layouts like this because all the old original Fender amps are drawn like this.
You can rotate the tube sockets if the pins are on the 'wrong' side.
Look at this simple Marshall layout. Works equally well for Fender...
http://sluckeyamps.com/6v6plexi/6v6plexi.pdf (http://sluckeyamps.com/6v6plexi/6v6plexi.pdf)
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Mike - when I built mine, I ran into the same thing, so I just built it with the pots going right to left and the input and power switch on the right. I didn't really feel it was a problem at all. Power switch could have been rerouted to the left side on the front, but I wanted it close to my PT.
Sluckey - that is really nice. Thanks for sharing.
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Mike - when I built mine, I ran into the same thing, so I just built it with the pots going right to left and the input and power switch on the right. I didn't really feel it was a problem at all. Power switch could have been rerouted to the left side on the front, but I wanted it close to my PT.
Sluckey - that is really nice. Thanks for sharing.
Definitely starting to agree with the right to left idea. You can see the problem from the mock-up. Thankfully the mistake cost me a $.50 sheet of cardboard. Learning not to start chassis or board drilling until I see how everything will fit.and line up. Unfortunately made a $25.00 mistake by having the faceplate and back plate made too early but it is what made me cathch this.
Thanks
Mike
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I do all my layouts with tubes across the bottom, pots across the top with input jack(s) on the top right. My layout matches the bottom view of an amp with knobs pointed away from you. Fender is the same as Marshall. I started doing layouts like this because all the old original Fender amps are drawn like this.
You can rotate the tube sockets if the pins are on the 'wrong' side.
Look at this simple Marshall layout. Works equally well for Fender...
http://sluckeyamps.com/6v6plexi/6v6plexi.pdf (http://sluckeyamps.com/6v6plexi/6v6plexi.pdf)
Thank you sluckey for your help. I am enjoying the MS-Visio. Would be worthless without your amp parts, etc.
Figured out what you were saying about the layout in the middle of doing this but already had a couple hours of work in it and just wanted to use it for my mock-up. It accomplished what I wanted it to do but I will use your system in the future. Still having a difficult time getting away from the cut and paste world. I like a full-sized mock-up where possible. Easier to see where wiring problems or solutions and transfer them to the build for me.
Thanks
Mike
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I've been using Visio since version 1. All it could do back then was organization charts and flow charts. It's come a long way! Drawing schematics and layouts for guitar amps is just a fraction of what Visio can do. I've even used it to layout a nice landscape. IT people use it to draw nice network diagrams. And on, and on, and on...
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I do all my visio layout just like I like to work on amps
The pots are closest to me and the tunes are farthest away
This makes way more sense to me than the reverse
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Unfortunately made a $25.00 mistake by having the faceplate and .......
Where did you have them made?
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Where did you have them made?
Guys I have a great contact for faceplates. https://www.facebook.com/WaspEngravings/ (https://www.facebook.com/WaspEngravings/)
Also Mike, I have transferred my builds to combo style. One thing I have discovered is some tube sockets are oriented differently. Parts Express ha s 9-pin socket that requires a 3/4" punchout rather than a 7/8. The pins are positioned a different way in association with mounting holes than other tube sockets I have used.
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Unfortunately made a $25.00 mistake by having the faceplate and .......
Where did you have them made?
I have the faceplates and back plates made by a local printing / sign shop. They make them on vinyl covered by a laminate. Seems to be quite durable. I use Inkscape to do the programming and when I am done email the files to him. He prints them and calls me when they are ready. I chose this method because silk screening is very expensive unless you are making many identical amps. Also this is thin so long shafted pots and jacks aren't necessary. I am very happy with it. Plus it is not that big of an expense to make changes.
Thanks
Mike
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Attached is the initial mock-up of the Deluxe Reverb one-channel build with a passive effects loop and PPIMV. I have compared it to Doug's AB763 one channel schematic using the yellow highlighter method and except for the addition of the fx loop and PPI circuitry it agreed.
I used MS-Visio as much as I could but had to resort to cutting and pasting various files together in order to get everything life-sized on the mock-up. This will help in making boards and in measuring for the faceplate and back plate using Inkscape.
Hopefully, this is a better effort than the cut and paste and white out modifications to Doug's original layout drawing which ended up being unreadable.
I was hoping in posting this is to get opinions concerning the layout. For example, does anyone have an opinion regarding what the proper distance is between power caps from the pots when the power caps are on the main board? I am thinking it might be a good idea to move the main circuit board away from the pots maybe another inch. Hopefully, this would help ensure that the electrolytic caps on the board don't get too close to the pots and the signal running therein. Don't have any scientific rational as to why I should do this or not though.
Other questions I could think of include, does it make any difference whether I ground the shield for the cable going from the circuit board to the preamp – in jack on the preamp ground or the power ground? Also, does the feedback wire go to the eight ohm tap? Additionally, are there any must have mods that you would add to this given the room I have in the chassis? Would be nice to get all of the changes done before drilling on the chassis or ordering another faceplate or back plate.
Thanks
Mike
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If you are concerned about your PS E-caps, couldn't put them all on one separate board and then maybe move that an inch closer to your PT? :dontknow:
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If you are concerned about your PS E-caps, couldn't put them all on one separate board and then maybe move that an inch closer to your PT? :dontknow:
When Doug made his AB763 build he put most of his power caps in front of his main circuit board. I read somewhere that it is advantageous to keep the electrolytics and their grounds as close as possible to the circuitry they are feeding. That is the reason I didn't put the preamp electrolytics on a separate power board. I am not certain whether Doug placed his in front of the board for that reason or due to space limitations in his chassis.
Thanks
Mike