I'm thinking about buying an amp kit to put into a Onkyo M504 donor chassis. Its a dual mono design with ~ +/- 70v rails. Power supplies are good and its got great big meters on it. It was hit by lightning and repaired in the past. I bought it after it died a second time. I then got it working for all of about 4 hours before blowing the right channel again. A few weeks later, a slip of the test probe blew the left channel. Each time it dies there are may low level components that fail along with the main outputs including $20 dual jfet inputs. I've got waaaay more time/money wrapped up in it than I care to admit. There are also plenty of cheap/fake ebay parts I put in before I knew any better. All in all, I just don't want to mess with fixing it anymore.
I kinda thought about going low wattage class A like a Pass. One of my other amps is a HK Citation 16a. Its ~150 WPC but runs in class A for 5 watts and can heat the whole room. 😀 Maybe I already know what good Class A can sound like since I have efficient JBL speakers? I also have a Phase linear 400 with the white oak board that is powerful and sounds great with my lower efficiency speakers. I could go in any direction with this I guess.
Anyway, would you guys have some quick recommendations on an amp board kit that meets or exceeds the originals sound quality? What would you do it it was yours?
I kinda thought about going low wattage class A like a Pass. One of my other amps is a HK Citation 16a. Its ~150 WPC but runs in class A for 5 watts and can heat the whole room. 😀 Maybe I already know what good Class A can sound like since I have efficient JBL speakers? I also have a Phase linear 400 with the white oak board that is powerful and sounds great with my lower efficiency speakers. I could go in any direction with this I guess.
Anyway, would you guys have some quick recommendations on an amp board kit that meets or exceeds the originals sound quality? What would you do it it was yours?
Well, I would go for FO 1.4 modules
Non expensive and seems excellent VFM... Or rather sound for money. Plus these seem perfect to fit in older amps to give them a new life.
See Vendor section for detail and you might perhaps need some small thinking to resuse (if you have to) your current linear PS
I hope this helps
Claude
Non expensive and seems excellent VFM... Or rather sound for money. Plus these seem perfect to fit in older amps to give them a new life.
See Vendor section for detail and you might perhaps need some small thinking to resuse (if you have to) your current linear PS
I hope this helps
Claude
My speakers are 101 db@1W 1m but I like to have dynamic range for classical music. So I like to have 30-35 v peaks available when I'm listening at a .5 v base level. 1812 overture starts soft but has a cannon shot near the end. I'm using a single 70v power supply. Less voltage available requires a restricted dynamic range source like the old LP's of the fifties.
For +-70 the only IC I know of is TDA7293. I looked, ST are not selling the evaluation boards anymore. So you would have to build on bare board or perf board. Or look for a kit at chipamps or someplace. LM3886 the standard kit will only use one of the rails. LM3886 won't go quite that high in peak current, anyway.
The advantages of class A are bit lost on me, since with adequate idle cross current on class AB I'm getting the best simulation of difficult source like top octave piano or bells I've heard in my life. I can't see playing 1812 overture all at 1/2 volt. That would be like musak. Mozart, or CPE Bach on a harpsichord or clavicchord, maybe. No piano, there is too much power in the hammerstrike of a Bosendoerfer for 5 watt max IMHO. The pings of George Winston on his Bosie are like icicles breaking off the tree limbs in a high wind. On CD or LP, the youtube MP3 versions of his tracks sound like porridge.
For +-70 the only IC I know of is TDA7293. I looked, ST are not selling the evaluation boards anymore. So you would have to build on bare board or perf board. Or look for a kit at chipamps or someplace. LM3886 the standard kit will only use one of the rails. LM3886 won't go quite that high in peak current, anyway.
The advantages of class A are bit lost on me, since with adequate idle cross current on class AB I'm getting the best simulation of difficult source like top octave piano or bells I've heard in my life. I can't see playing 1812 overture all at 1/2 volt. That would be like musak. Mozart, or CPE Bach on a harpsichord or clavicchord, maybe. No piano, there is too much power in the hammerstrike of a Bosendoerfer for 5 watt max IMHO. The pings of George Winston on his Bosie are like icicles breaking off the tree limbs in a high wind. On CD or LP, the youtube MP3 versions of his tracks sound like porridge.
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And tell me where do you find this information?Its a very dangerous statment.If you dont know what you writing then dont write at all.
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