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The "$250" Amp? - 6LU8 Compactron SE, UL

Kegger said:
With a pretty standard 120v wall voltage you should be able to follow the build just right.
Click to expand...

I'm having trouble determining what different types of capacitors I need to order from the BOM. I'm fairly sure the electrolytics are the small cans with either 1 lead on each end or two on the same end, like the common blue, grey, or black ones in most electronics... correct? C2 & C3

What are By-pass/coupling, poly or oil capacitors (C1, C4, C5, and the .47uf caps in the PS) ? I find polypropelene and polyester, no oil. Are these the flat, rectangular type?

Which are the large, can-shaped ones? the 150uf and 7uf?

I've been able to find the tubes, all the resistors and some of the caps at Antique Electronic supply. I'm also finding that no one seems to carry everything, so there will be multiple orders. Is the Antek transformer only available directly from Antek?



.33 uf 250v By-pass/coupling, poly or oil Capacitor (C1, C4)
.33 uf 400v By-pass, poly or oil Capacitor (C5)
33 uf 400v Electrolytic Capacitor "can be a poly cap" (C2)
220uf 100v Electrolytic Capacitor (C3) (50v rating on up, and upto 470uf)
1uf 400v poly or oil Capacitor (additional input caps for supply voltage tweak)
150uf 400v Electrolytic Capacitor (power supply cap) (120uf will work here as well)
.47uf 400v By-Pass, poly or oil Capacitor (power supply bypass) (can be same as C5)
7uf 400v poly or oil Capacitor (input cap for supply) (6.5uf - 9.5uf here)
 
The ones with leads on both ends are called axial and the ones with both leads on one end are called radial. And yes, those are the
common caps in aluminum cans with plastic coatings which are those electrolytic caps for the power supply and possibly decoupling.

Oil means paper in oil: http://angela.com/angelajensensequapaperinoilsignaltypecapacitors.aspx PIO caps..
Also the Russian ones from Ebay are nice and inexpensive

For bypass and coupling caps, I used Dayton and Jantzen from PE: POLY means polypropylene
http://www.parts-express.com/crossover-capacitor-index.cfm

Not sure if you mean in my pics but the big caps on top of the amp on mine are the 7uF motor run cap and the C2 33uF caps. They
were just a choice I made and you don't have to get the same thing. (There a tweak I did and many use these type caps in there)
(these are quite often oil caps as well, or at least referred to as)

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Here are the electrolytics in my amp:
6LU804.jpg


The 150uf an 220uf are snap in type. Yours don't have to be.

I'm pretty sure no one else but AnTek carries that AnTek iron.
 
sled108 said:
I've looked there, but have never seen 6Lu8 listed...What should I look for?
Click to expand...

If you do a search for 6LU8 you should find a fair amount of info, I also believe a
thread involving Tubelab and myself going over a build may have Spud in the title.


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Thanks for posting the pic's Goya, and helping people in the thread, appreciate it. :thmbsp:
 
I've got a SE build in the works utilizing E-Linear.(completely different then this)

But with that setup you need/want a pentode as the driver for larger gain/swing.
(there's a fair amount of feedback with that design, so more gain needed/wanted)
 
I'm leaning heavily towards building a Hagerman Cornet phono pre but I'd like to hear what you can say about that phono pre.
 
Well..Goya...I'm still Burning it in...But it does Sound Good...I has wonderful Mids & Highs Right off of the Schematic...I've used a variable Resistor at R5 which controls the 50-100 Hz...So, I'm Messing with that, plus the Caps need to Season..But, it still has a Great 'Tube' Sound...I'm Running it against a Marantz 7T, and a SkyCoral OPA2227 PhonoAmp...The only Drawback that I can tell about it is that it has a Lower OutPut and you Need to Twist the Joy Knob a Tad more...But the Dynamics are Still Right, and Maybe I'm not Running the 6DJ8's as Hot as I could...Come on Now...2 RS 12.6Vs at 134V B+?? Other than That....Check the Insides that I just posted...How's your 'Solder Hand' ? The Schematic looks Sweet and Easy...The Reality looks like the Pic...A Real 'Oil Refinery' Challenge...The Choice is Yours...

Here's how it Sounds...Kinda....I guess for this Tune a Giant Pair of Cervin Vegas are what's Needed...I just hope the your Computer Speakers are...'Not Fragile'....


http://www.youtube.com/watch?v=uurGBvwGQY0
 
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GOYA said:
I'm leaning heavily towards building a Hagerman Cornet phono pre but I'd like to hear what you can say about that phono pre.
Click to expand...

Hey GOYA, I built the Hagerman Octal Cornet. It sounds great. I had an original cornet here for a bit and did many hours of A/B comparisons. The Octal won hands down. Much fuller sound and greater detail.
 
No, you can swap 12AU7s (9 pin) out for 6SN7s (octal) and 12AX7s (9 pin) for 6SL7 (octal) with a few changes in components in the schematic. Hagerman has published octal variants of both the Cornet and Cornet 2.
 
Hey Kegger...Any thoughts on how to Kick it up a Notch with the 6LU8's...I've a couple Sets to Spare, and would like to Hear what They can do..Right now the Amp sounds Great, but it seems to be Holding Back a bit...Can I make it Cry and Sing?
 
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