adnick
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Was wondering if I might be getting a bit too anal
DIY Another set of mono 300B amps or walking the diy plank 0-:
- Thread starter adnick
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Do It Yourself
Wait— what now?
forget the the 300B that table is awesome!!!Here’s what I’m thinking, the top will have a horn speaker type curve, the base is projected to be 9”x12” —was wondering if I could get away with the 300B tube in the center position a bit forward?
Of course that can certainly change as parts arrive and comments ensue
View attachment 95799
Andre.
adnick
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I kinda figured that, when the Lundhal 2785c arrives I’ll post some photos; it will need a cover, are there any technical concerns about the cover type/material?
Thanks,
Andy
adnick
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Thanks, but It’s just an old barn door
adnick
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Originally thought about a 41 tube but after discussing the project with Paul_b, the plan is replacing the 41 tube with 7B5/6K6 using one of Paul’s designs—project wouldn’t be possible on my end without his help/expertise 👍
Andy
Yeah. Ever considered to have the PSUs separated? Handling of units is much easier, no interaction of magnetic fields, and if you need a PSU for eg testing/constructing another amp, you already have finished PSUs.
I have the strange habit to give every tube its own PSU/B+ (and also own filament PSUs), have a bunch of external PSU units.
Used to be very helpful when finding problems just by switching left/right units too.
RPMac
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Thanks, but It’s just an old barn door
Old barn wood is always interesting…hundred year old board from a hundred year old tree 🌳Thanks, but It’s just an old barn door
Umbilicals are notoriously unreliable, and you actually lose control of whether the components interact, as the power supply can be put in a large number of locations and orientations.
Simply: No Sir.
And positioning PSUs out of any OPT interaction range is a superior feature.
Remember that this is the OP's first build and a straightforward build will more likely be successful especially since the designer doesn't consider remote power supplies to be necessary for quiet operation. If he were building a phono-stage then it might be worth the additional effort
Thinking back over all the equipment with umbilicals that has rolled across my bench, I'd estimate that more than half of those components required repair to the umbilical cord as part of the service work. I even had one preamp where I fixed the umbilical and it came back a few months later with a different wire inside the umbilical severed.
I'll also reiterate that having a separate power supply introduces the possibility that some future owner will set things up in a sub-optimal way and induce the exact interaction that could be avoided by simple proper arrangement of the iron in a traditional build.
adnick
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Parts are showing up daily, might be able to actually start working on the amp in a week or so….
Kinda been on double secret medical probation and haven’t been working in the shop but should be back at it this week.
Since the Bottlehead C4S was sitting in the parts box so it was something to do while cooped up in the house ….. @paul_b had explained to Dave how to separate for mono use, so thought I’d see if I could follow instructions.
Kinda been on double secret medical probation
and haven’t been working in the shop but should be back at it this week.Since the Bottlehead C4S was sitting in the parts box so it was something to do while cooped up in the house ….. @paul_b had explained to Dave how to separate for mono use, so thought I’d see if I could follow instructions.
adnick
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Agreed Ed 👍 It’s certainly good distraction therapy
