W A R N I N G !


W A R N I N G !

This page is full of non-facts and bullsh!t, (just like the internet and especially forums and other blogs), please do not believe entirely without exercising your intellect. Any resemblance to real things in reality is purely coincidental. You are free to interpret/misinterpret the content however you like, most likely for entertainment, but in no case is the text written on this blog the absolute truth. The blog owner and Blogger are not responsible for any misunderstanding of ASCII characters as facts. *cough* As I was saying, you are free to interpret however you like. *cough*

Monday, June 15, 2009

Downward-firing speaker


My idea of a joke.

It sounds like... downward-firing speakers.

The thing powering the speakers? It's the NAD 3225PE that I just repaired.

And the fan on the 3225PE? The handy 120mm Sunon running on 5V powered by the handy 230V -> 4-pin molex adaptor, cooling the amp.

I'll talk about the amp. I bought it from another forummer on XtremePlace garage sales forum.

The seller described it as left channel faulty, only right channel working with CD/AUX input. He also mentioned preamp + phono amp most likely not working when asked. Which I found strange, because you'd be testing your gear to see how much of it is working to boost the sale value, instead of saying "most likely not working".

I do not consider "something glowing and producing smoke inside" as "right channel working" condition. But that is what I saw upon powering up. No wonder he did not test the rest of the circuit - who would have the guts and brains to?

Considering the risks involved with glowing things and reduced possible rewards, $30 is too much to ask for something that may have the only working part being the chassis.

While the sense of value varies between people and the value of this thing is uncertain, if he had any integrity he wouldn't delete the thread immediately after.

And he still had the cheek to tell me this thing was in storage for a long time and one day when he decided to use it it just spoilt. A post of the symptoms at diyaudio forums quickly gave me a response that this is a usual case of thermal runaway that occur in this series of amps (with the pros there even pointing out correctly which are the other parts that got fried). Rubber marks on the top cover further supports this suspicion - something was placed on top of the amp, when the manual explicitly stated to have at least 50cm of clearance on top of the amp, and is something you ought to not do with a passive-cooled top-vented device rated at 150W, as common sense says.

Was he a young lad? Nope, he's an uncle. I've met more uncles than young chaps with bad sales behaviour actually. Seems that society screws your character.

Fortunately this catastrophic failure turns to be a plus, as it is a known common failure with solution available, and the seriousness of this means that the rest of the system would be in working condition, since this alone renders the product unusable.

Maybe not for those wanting to use part of its function, attracted by the $30 "partially working condition", and getting pissed when they see smoke. The seller said I was the first to respond and there are two others behind me, which is strange because that would mean that nobody responded for the at least 1-2 days after he posted the thread and 3 responded within the next 12-hour time frame, but I could be wrong.

A few talks with the pros, schematics in hand, more than $40 worth of replacement parts, a few weeks of waiting and decision making, cutting of PCB traces, the most exciting part - first power up,

Viola! I got a vintage SS amplifier for $70.

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