a twreck build started - questions

[rockstah]

Those big 16AWG brown wires are the heaters. The brown/white is the heater CT. For an Express you want to use the 300VAC wires.

the Heater CT goes to ground, correct?

the gray (5v @ 3A) is my PT secondary? ?

[img:161:120]http://img1.putfile.com/thumb/9/24901232176.jpg[/img]

[Normster]

I think this pic will help clear things up. I changed the PT wiring colors to match Moose's trannys.

The brown/white and red/yellow wires both go to ground.
The yellow (300V) wires are your PT secondary.

The gray (5V) isn't used. It's a heater supply for a tube rectifier (like a Rocket/Liverpool).
The yellow/green (260V) also isn't used, except in the Rocket/Liverpool with EL84s.

[rockstah]

appreciate that my friend!

[rockstah]

so the electrolytics/filtering - three 20u's - three 40u's and two 22u( cathodes ) - wonder if anyone has done this with three 22u - three 47u and two 25u( cathodes?

(the diagram shows three 22u, two 47u and one 33u )


as well I'm pondering if i want to use mustards, sozo's or orange drops for the coupling (tone) caps.

any food for thought appreciated here.

Mark

[Normster]

I used 3 x 40uF and 3 x 20uF Sprague Atoms for filtering and 25uF Atoms for cathodes. I can't actually hear the difference between 22uF and 25uF.

I believe the coupling caps were Mallory ODs in Francesca but I used Sprague PS series ODs from tubesandmore. I've read that they're very close to the Mallory. I try to stay away from 715s since they are noticeably harsher in my Dumble builds. Haven't tried the Mallory 150s but imagine they would be a bit smoother sounding.

[keithrick]

I used 3 x 40uF and 3 x 20uF Sprague Atoms for filtering and 25uF Atoms for cathodes. I can't actually hear the difference between 22uF and 25uF.

I believe the coupling caps were Mallory ODs in Francesca but I used Sprague PS series ODs from tubesandmore. I've read that they're very close to the Mallory. I try to stay away from 715s since they are noticeably harsher in my Dumble builds. Haven't tried the Mallory 150s but imagine they would be a bit smoother sounding.

+1, I built mine the same way as Norm, I did however intially use the Mallory 150 series and they sounded fine. I then switched to the PS series as I had extra from a ODS build. If I had to compare to the PS series I would say that the midrange is a little clearer with the PS series. The Mallory's did seem a little warmer/smoother as Norm suggested. Some would also consider this muddiness. I would try both or a combination. Good luck!

[rockstah]

i hear ya. so whats up with the layout that shows three 22u - two 47u and one 33u - is this another amps spec?

[rockstah]

so no one has tried mustard caps?

[rockstah]

I used 3 x 40uF and 3 x 20uF Sprague Atoms for filtering and 25uF Atoms for cathodes. I can't actually hear the difference between 22uF and 25uF.

I believe the coupling caps were Mallory ODs in Francesca but I used Sprague PS series ODs from tubesandmore. I've read that they're very close to the Mallory. I try to stay away from 715s since they are noticeably harsher in my Dumble builds. Haven't tried the Mallory 150s but imagine they would be a bit smoother sounding.

where can one get these mallory OD's?

we have
Type PS Orange Drop Capacitors

Polyester film, radial leads, +/-10% tolerance





Type 715P Orange Drop Capacitors

Polypropylene film. Radial Leads. +/-5% tolerance. Rated for 85° C Operation





Type 715P Orange Drop Capacitors

Polypropylene film. Radial Leads. +/-5% tolerance. Rated for 85° C Operation



CAPACITOR, MALLORY 150'S, .0022 µF @ 630 V

Tubular metalized polyester construction
±10% tolerance
Axial leads
Non-Inductive, Self Healing



what did Ken use? Polyester film or Polypropylene film is the question.

Mark

[Normster]

Sorry, forgot to mention that. Ken used Mallory PVC601's in Francesca. 600V, Polyester film, +/-10% tolerance. (Same as Sprague 6PS series.)

New stock is all manufactured by CDE I believe. Just rebranded for Sprague, Mallory, etc.

[rockstah]

PVC601 CA955 Mallory .1uF X 600V PVC Mylar/Paper

hmm still looking but cant quite seem to find the values i need of the PS6 series caps. .022, .0022, .1 ... still searching.

[rockstah]

whats the b+ of the 300 taps and the 260 tap?

can someone talk about the 5200 and 6600 settings on the OT?

[gearhead]

PVC601 CA955 Mallory .1uF X 600V PVC Mylar/Paper

hmm still looking but cant quite seem to find the values i need of the PS6 series caps. .022, .0022, .1 ... still searching.

The PVC 601's are Polyester Film/Foil, sometimes also listed as Mylar:
http://www.acksupply.com/catalog/caps.p ... 20Mylar%22


Mallory is now a division of Cornell-Dubilier, so you will now find them under that name, such as at Allied:
http://www.alliedelec.com/Search/Produc ... ESC=PVC601

Big Power Filter Electrolytic Caps = Mallory TC series ( TC 75, 78 )
Smaller Electrolytic Caps = Rubycon (no longer made)
Big (Orange) Caps = Mallory (now CD) PVC series
Smaller Caps = Mostly Silver Mica

If you haven't already done so, highly recommend downloading the pics of Francesca. BIG, great, great shots. You can read the brand and part numbers on most components.

[philmanatee]

Email allynmey with a list of parts you need, I think youll be pleasantly surprised. Phil

[rockstah]

hey thanks people!
ill be back on monday - have a few shows in calif and ohio!



Mark

p.s. my parts from allynmey should be here by then.