Review: Onkyo M-508 Amplifier

Category: Amplifiers

I like the way sound decays on this amp - it gives a luxurious feel to it. The color is not neutral though - it has a forward sounding treble, while pretty, can sound fatiguing with a strong tweeter. It looks nice enough. I think some of the top end Japanese products are ok (denon, yamaha, onkyo). You might be pleasantly surprised. Some reviewer compared it to sunfire amps. If you can pick one up for a few hundred dollars, it might just be your ticket to audio nirvana at a reasonable price - I love the luxurious feel of this amp.

Associated gear
Marantz CD player
M 506r pre onkyo
Ribbon tweeter american speaker (no longer in production)

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I had the baby brother M-504. It was bulletproof. I finally sold it to change to Adcom & Parasound. I liked everything except the binding posts-they won't accept spades.
Great sounding power amplifier. I had 2 504's bi-amped after selling my 508. I replaced it with the new sunfire signature 7-channel amp, which allows me to now incorporate home theater. If you can find one, I highly recommend buying this piece. Mine were purchased overseas and was dual-voltage.
I wonder how much of the treble problem isn't a room issue more than an amp issue. I doubt that Onkyo would design a flaw like that into their amp.
I got mine Grand Integra M-508 twenty years ago on the tropical island of Guam for $550(while in the Air Force). It's been hauled all over the world with me and used at least twice a week(for hours on end). The only problem I've had is one of the green lamps on the right power meter burned out-- other than that it has been bullet proof. It has no problem with the treble-it has always had a deep,smooth,rich,luxurious sound--sort of like a 70's vintage high end Marantz. However, I am worried that the eight huge 10,000uF capacitors are going to go bad in a few years(just due to old age), and to get them replaced would cost about $500 for parts and labor.