L'Amp: A simple SIT Amp

Chassis

My chassis is slowing coming. It is 18x15. The heat sink is 14"L 4.5"H 3.5"W. I thought it's good enough for this job. Is the choke placed in the right position for less interference ?
 

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Looks about right to me. I would chrome plate the transformer covers and those corners for a more spiffy look when you finish testing.

I like it as it is. imperfections , contrasting colors, recycled stuff.

I am very interested in hearing how the LAMP with 2SK180's sound. I have some too, have not gotten around to building with them however. Looks like I need a giant heatsink!!!
 
I like it as it is. imperfections , contrasting colors, recycled stuff.

I am very interested in hearing how the LAMP with 2SK180's sound. I have some too, have not gotten around to building with them however. Looks like I need a giant heatsink!!!

I'll post on every step I go. Hope someone with experience will give guidance and or advice. The Chassis looks big, but it's big if compare to my other amps.
I still have trouble to place all those parts around, up and down.:confused:
 
Hi there, My sit amp has a slightly tilted up sound, or a keenness in the higher parts of music over the lower register content.
Im on a quest to boost its lower freq. tone a little.
My amp is the MR single ended, fixed bias design (no source resistor)
Its loaded with a 12R power resistor with 27V on the drain. The 2sj82 is drawing 1.8A , I have a 10Uf input and 15000uf output blocking caps.
Is there any direction i could go to darken the amp?
 
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Joined 2009
Paid Member
Hi there, My sit amp has a slightly tilted up sound, or a keenness in the higher parts of music over the lower register content.
Im on a quest to boost its lower freq. tone a little.
My amp is the MR single ended, fixed bias design (no source resistor)
Its loaded with a 12R power resistor with 27V on the drain. The 2sj82 is drawing 1.8A , I have a 10Uf input and 15000uf output blocking caps.
Is there any direction i could go to darken the amp?

Wire wound resistor was darker, thick film brighter in my arrangement.

The solution was an inductor changes the sound completely in a darker direction and gives more power, but Helas less transparent of course than the resistor solution.
 
The passives, especially the coupling caps contribute significantly to the perceived tonal balance. Don't know what you have in there atm, but a large Mundorf Mlytic at output may push the sound in the right direction.

Or paralel good quality big film caps to humbler electrolytics output caps. ;)

Good luck,
.M.
 
Hi Michael,
the idea of Juanitox of using tube rectifiers instead of lamps is pretty good (lamps are really rare here in Europe).
Can you suggest some other workarounds like this? For esample also halogen lights could be ok?
It would be great (for dumb like me!) to have some advices in this respect.

Thanks a lot!