After looking into the chassis thing and trying to fit the full PSU and the transformer in a box, decided to go the 5U chassis rout.
Whats another 60 bucks at this point, right?
A little more room to work with and more heat sink.
When does your chassis arrive?????
I don't think I could make a 3U work... unless I throw symmetry completely out the window... Which I might be able to get over at some point in my life. Not today—pic attached of my current layout. I may end up rotating the PSU 90degress clockwise. Height isn't really the issue... it's depth.
I've been stalking this thread for a bit now—and done a lot of reading—probably not enough yet. I'm pretty sure I know a lot less than you do about all of this amp craziness... Yes that has led me on quite a journey with the help of some key members up here (6L6 and Fidget). I've built 2 ACAs and a B1K (that thing is amazing)—for the F5, discrete diode bridge and full input snubber action and Quasimodo toroidal sensation-ing for me (Still need a scope). Also the "back" parts kit in the store went out of stock with that kit in my cart!... right as I pulled the trigger on the whole thing... So I got to upgrade my speaker posts (this was surprisingly not straightforward)—and figure out how to source the jacks and IEC (the store actually has this part listed, sorta—and NO it doesn't come with fuses when you buy it from Digikey or Mouser—Gah!).
I still have some seriously basic questions though—I know the wiring will be a challenge... and some basic "issues" that were interesting. For instance the PSU traces are so huge that I wasn't expecting such the soldering challenge... Things had to get pretty damn hot to start flowing. I also think I need to beef up my connections in terms of wire sizing between the diode bridge and PSU—I used 22 ga solid... and my instinct is telling me I should redo that, probably with clippings from some 14-2 I have laying about. Polarity of the LED was a total mystery on the board too. Some Quasimodo lessons came into play and I charged the board with a 9V battery to figure that out.
Pic below of my build layout in an 4U. Nothing is attached...still working it out.

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The differnce here is that i said 400mm. You have a 300mm 🙂 you also get more cooling capacity with 3U 400mm then you get from a 4U 300mm 🙂
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The differnce here is that i said 400mm. You have a 300mm 🙂 you also get more cooling capacity with 3U 400mm then you get from a 4U 300mm 🙂
YES! that would work...of course, of course. It's unclear if that includes the bottom perf plate etc... I found that pretty key to my noob-i-ness...
There is no 3U 400 deluxe...
I’ll look into that for the future. There’s one hole on the UMS that wouldn’t be able to be drilled, but that particular hole isn’t used in any of the Pass designs, so I think it would be no issue at all.
I’ll look into that for the future. There’s one hole on the UMS that wouldn’t be able to be drilled, but that particular hole isn’t used in any of the Pass designs, so I think it would be no issue at all.
Thanks for the heads upon the 3U chassis guys, did not even now that option was available.
Plus I save a few bucks and have all the equipment to drill and tap holes.
Ordering one tonight.
A deluxe version would be nice for people that do not have the capability though.
Plus I save a few bucks and have all the equipment to drill and tap holes.
Ordering one tonight.
A deluxe version would be nice for people that do not have the capability though.
Well, with the back panel parts kit OOS until the end of October and a chassis on the way.
I decided to source my own, found the Schurter 6765 on Digikey for 15.43 ( I chose the option of no light in the switch), had to order a few other things anyway.
The RCA connectors I purchased from PE for a total of 64.48 with shipping and sales tax.
A little over the original parts kit cost (which is a great deal no doubt) just couldn't wait.
I decided to source my own, found the Schurter 6765 on Digikey for 15.43 ( I chose the option of no light in the switch), had to order a few other things anyway.
The RCA connectors I purchased from PE for a total of 64.48 with shipping and sales tax.
A little over the original parts kit cost (which is a great deal no doubt) just couldn't wait.
...?? 65 bucks for the RCAs? Or is that including the binding posts??
The RCAs are $4.25 in single quantity Neutrik NF2D-B-9 RCA Jack D-Series White/Black
The RCAs are $4.25 in single quantity Neutrik NF2D-B-9 RCA Jack D-Series White/Black
Get some fuses!!! That's my current hangup... Can't find any locally... I too had to roll my own "back parts kit"...
Pic of where my F5 stands attached. Had a bunch of help from some fine peeps up here—You know who you are!
Ready to go with the bulb tester, fuses are here this week... Then I can test out the power supply,...and fingers crossed start the biasing routine.
!! Excellent fun.
Pic of where my F5 stands attached. Had a bunch of help from some fine peeps up here—You know who you are!
Ready to go with the bulb tester, fuses are here this week... Then I can test out the power supply,...and fingers crossed start the biasing routine.
!! Excellent fun.

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Checked the status of my 3U chassis order today and it was last tracked as being at Stansted airport in the UK but had of delivery date of this Friday, fingers crossed.
I am beginning to think maybe they will just fly over the house and through it out of the window.
Anyway, can you tell I am anxious
I am beginning to think maybe they will just fly over the house and through it out of the window.
Anyway, can you tell I am anxious
I finished my F5 , now I am doing the settings.
I set just one side at the moment and get these values, how good are they ?
Output >> 0 +/-
On R8 >> 0.367 v
Iq at PSU >> 33.7 v
I am on a 240v primary.
I set just one side at the moment and get these values, how good are they ?
Output >> 0 +/-
On R8 >> 0.367 v
Iq at PSU >> 33.7 v
I am on a 240v primary.
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