F5m kit

The downside with that arrangement, capacitors above the transformer, as i see it, is that the transformer will create heat. And heat rises.

And the added heat is really not the ultimate treatment in the really long run, for capacitors.

…That is If we really are getting into the weeds, and really splitting every single hair on the Carmels back. 🙂
 
I'd love to hear about how people are implementing the dual power supply option. I have the Modushop PassDIY chassis arriving this week. Curious about layout for both PS boards and thoughts about single or dual transformer? What do you all think?
I have one coming next week as well. I'm planning on using 2 x 200va, most likely situated side by side at the very front. Haven't made up my mind yet but since I have the dual supplies I figure might as well go all the way.
 
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F5m, part deux

I don't like monoblocks. They're ungainly, wires everywhere. I built my F5m that way initially only out of expediency & always intended to put it in a single chassis, but got restless waiting for others to enable my dream of a fancy custom 3U, so. In the 4U Deluxe it went, this time with Papa's intended power supply & a single Antek AS-2218 for transformation duty. Don't mind the wiring, I don't like to solder & I'm prone to re-use partial connectors I have laying around.

I built this power supply with the "matched" CL-60 thermistors I've talked about earlier, also out of expediency (or laziness). I wasn't sure this would work, but it did, the rails are 24Vish, the bias holds stable at 1.1A to 1.2A & the DC offset is <10mV cold to hot, both channels. Good enough for the main system.

The first records played were some blues- Howlin' Wolf (live in Europe, 1964, something I picked up in the Seattle airport), then Lightnin' Hopkins Blues In My Bottle, a record I know well. I've learned to love the way my 2-ways sound when slapped around by an amp with control, like an Aleph Classic, so I was hoping for bass presence, if not outright control. Those first two records were promising, considering how distracting the treble was at first. Bright, forward, clear detailed compared to the Aleph, but plenty enough bass, in a kind of 70's way. Interesting to me too that in my system, it almost sounds now like there's a transformer in the signal path. I don't know what that means yet.

Tonight was Jethro Tull's Stand Up, then a couple of Moody Blues records I acquired but hadn't yet listened to. The verdict holds, the F5m has quite a bit of bass control. This is a very good amp for me.
 

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F5m, part deux

Those first two records were promising, considering how distracting the treble was at first. Bright, forward, clear detailed compared to the Aleph, but plenty enough bass, in a kind of 70's way. Interesting to me too that in my system, it almost sounds now like there's a transformer in the signal path. I don't know what that means yet.

Tonight was Jethro Tull's Stand Up, then a couple of Moody Blues records I acquired but hadn't yet listened to. The verdict holds, the F5m has quite a bit of bass control. This is a very good amp for me.


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Some suggestions, which may or may not help, but is good practice:

  • uncouple the signal input and speaker output wires
  • tightly twist the speaker out wires and locate them to the bottom of the chassis and side wall of chassis
  • locate the signal input wires toward the top of the chassis and side wall of the chassis
  • tightly twist the AC power wires from IEC to connector block
  • tightly twist the DC wires from bridge rectifiers to power supply board
  • tightly twist the V+ V- Gnd wires from PS board to amplifier boards, locating the wires toward the front of the chassis, away from the speaker and input wires

- rotate the power transformer to see if there is a quieter position
 
I looked back a few pages and didn't notice an answer, but does anyone know or have estimates on when the power supply included versions will be available?

Edit: Or, if I go ahead and get the Core kit now, will the power supplies become available later?
 
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