Hiraga 20W class A

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My focus is on complementary-parts-steps. These sound much different, have much different characters (and cascodes, darlingtons and others get the influence in noise, in, at moment not regarded, distortions - every alteration of the signal - of all - involved active too - parts). The sum of (very much different) parts decide on how clean. The Hiraga, i did tuned some, I did build some, is a rumbling thing. Much fun, but never a clean tone.

What is your definition of clean tone? Do you know any of commercial amps or diy amps had that characteristic?
 
The most se sound clean. Stuff as first watt 1 - 3. Or most se-tubes. Result of less parts, less stages, no different stages (pp) or very different stages (complementary-pp). The most tubeamps have got better psus (c-l-c as example). But: clean speakers are necessary to assess - no multiway, no crossovers, no rumblimg wooden-casings, tuned drivers ...
And clean sources: no wadia, no teac ... no massive recordplayers ... no complex multistage-riaa ...

My mind,-!
 
Anyone have an opinion about using MJL 1302 and 3281 as outputs? According to Farnell these are high quality audio transistors.

One of the best. Now I using MJ15024G+MJ15025G, cause my heatsinks made for TO-3.
 

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The most se sound clean. Stuff as first watt 1 - 3. Or most se-tubes. Result of less parts, less stages, no different stages (pp) or very different stages (complementary-pp). The most tubeamps have got better psus (c-l-c as example). But: clean speakers are necessary to assess - no multiway, no crossovers, no rumblimg wooden-casings, tuned drivers ...
And clean sources: no wadia, no teac ... no massive recordplayers ... no complex multistage-riaa ...

My mind,-!

You have a point there. But it may be personal taste. I also like my SS SE amp than Hiraga amp, my amp based on Power Follower with addition stage and gain, its topic was somewhere in this forum.
 
Lie around for ten years or more ...
two pairs of "Le Monstre", two pairs of "Le Classe A" and others. A little angle to attach, and they would run. But it hurts my ears, my aesthetic,-)
Do you not listen the difference, clean or less clean,-?

Some suggestions for the origin Classe A:

Replace the big copper strands by solid core, 1,5 mm.
New order of ground an C-R-C - look picture.
Replace the origin bridging cap by x times 220 uF or others, same types! same values! as much as possible.
Input only one channel ground - I prefer right.
Psu - amp: 0,6 mm.
Input - amp: max 0,2 mm.
Amp - output: 0,6 mm.
NO lace! Exept laqueured lace.

... to get a much cleaner, finer sounding origin - or diy - "Le Classe A"-!!!
 

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Founder of XSA-Labs
Joined 2012
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Lie around for ten years or more ...
two pairs of "Le Monstre", two pairs of "Le Classe A" and others. A little angle to attach, and they would run. But it hurts my ears, my aesthetic,-)
Do you not listen the difference, clean or less clean,-?

Some suggestions for the origin Classe A:

Replace the big copper strands by solid core, 1,5 mm.
New order of ground an C-R-C - look picture.
Replace the origin bridging cap by x times 220 uF or others, same types! same values! as much as possible.
Input only one channel ground - I prefer right.
Psu - amp: 0,6 mm.
Input - amp: max 0,2 mm.
Amp - output: 0,6 mm.
NO lace! Exept laqueured lace.

... to get a much cleaner, finer sounding origin - or diy - "Le Classe A"-!!!

Are these 3D dead bug amps truly PCB free? Do you have one attached to a heat sink and peripherals like inputs, power, output? It would be cool to see how you manage all that without having something bolted down. Cool looking though.
 
Have found pictures. But not a Hiraga. A Aleph 3. 8 years ago? For a friend. But he did not trust in thin diameters - I love thin diameters.-)
 

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Guys, someone was saying something about using multiple resistors to get 0.33 or 0.4 ohm..... Can't find that post anymore. But it was supposed to improve the Hiraga a lot. Does anyone get this? And what types should be used? Wirewound?

Thanks!

Hi Sjoerd,
Yup, it does improve the sound clarity and other aspects allot and lower the overall noise. To get 0.33 you need to parallel 3 pcs of 1ohm @3w ,metal oxyde. These will get hot even at 3w but acceptable. Or wirewound non inductive types could be used here . I havent tested wirewound n.i. but have tested simple wirewounds and will never go back to them.
Cheers
Sergiu
 
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