Gary D Olson
Skilled Tightwad
Yamaha m-70, c-70, & t-70 fixed, thanks to rob41!!!
Greetings.
It's hot here in Southern California - triple digits - yet I drove 30 miles to Pasadena to meet a craigslister selling the above Yamaha gear for $300. We agreed on $250 over the phone.
When I arrived, I plugged an iPod into the preamp (c-70) and switched everything on. The music from the LEFT channel sounded scratchy and much less volume. "Bad LEFT speaker" I ask myself?
I unplugged both speakers, then plugged the LEFT speaker with the ungodly sound into the RIGHT channel of the amp and it sounded great. Okay; it's not the speaker. Bad speaker terminal on the amp, perhaps?
I switched the speaker back to the LEFT channel on the amp using speaker "B" output. It sucked again. Hmm. Not the speakers or the amp terminals. Bad LEFT channel on the amp?
I inverted the L/R RCA connection coming from the pre, and it sounded great again. Good. That proved it isn't the amplifier. It also proved the RCA cable is working properly. (Gulp) Bad iPod connection? (PLEASE)
I invert the RCA left/right coming from the iPod. It sucked again. That narrows it down to a bad LEFT channel on the preamp. I told the seller (who had no idea what to do through all this) that a repair would likely start at $60 and offered him $190.00 for the trio. He took it.
The tuner was bundled and is of no concern at the moment. I was mostly after the amplifier which works and sounds fantastic, but 4 VU meter lights are out and I'd like to fix that. I also need to fix the preamp and either use it or sell it. I'm no repairman, but I'm fearless at TRYING to fix things with a "successfully-fixed / still broke / utterly-destroyed" ratio at about 70/20/10. Oh, and I do own a cheap multimeter thing-a-ma-jig and soldering iron. I'd greatly appreciate any advice about DIY repair on this, even if your advice is that tinkering around the innards of these components is best left for experts. If that is the case, I'll pay to have it repaired (in 2048).
Thanks!
Greetings.
It's hot here in Southern California - triple digits - yet I drove 30 miles to Pasadena to meet a craigslister selling the above Yamaha gear for $300. We agreed on $250 over the phone.
When I arrived, I plugged an iPod into the preamp (c-70) and switched everything on. The music from the LEFT channel sounded scratchy and much less volume. "Bad LEFT speaker" I ask myself?
I unplugged both speakers, then plugged the LEFT speaker with the ungodly sound into the RIGHT channel of the amp and it sounded great. Okay; it's not the speaker. Bad speaker terminal on the amp, perhaps?
I switched the speaker back to the LEFT channel on the amp using speaker "B" output. It sucked again. Hmm. Not the speakers or the amp terminals. Bad LEFT channel on the amp?
I inverted the L/R RCA connection coming from the pre, and it sounded great again. Good. That proved it isn't the amplifier. It also proved the RCA cable is working properly. (Gulp) Bad iPod connection? (PLEASE)
I invert the RCA left/right coming from the iPod. It sucked again. That narrows it down to a bad LEFT channel on the preamp. I told the seller (who had no idea what to do through all this) that a repair would likely start at $60 and offered him $190.00 for the trio. He took it.
The tuner was bundled and is of no concern at the moment. I was mostly after the amplifier which works and sounds fantastic, but 4 VU meter lights are out and I'd like to fix that. I also need to fix the preamp and either use it or sell it. I'm no repairman, but I'm fearless at TRYING to fix things with a "successfully-fixed / still broke / utterly-destroyed" ratio at about 70/20/10. Oh, and I do own a cheap multimeter thing-a-ma-jig and soldering iron. I'd greatly appreciate any advice about DIY repair on this, even if your advice is that tinkering around the innards of these components is best left for experts. If that is the case, I'll pay to have it repaired (in 2048).
Thanks!
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