The first article in this series involves the “HIGH POWER” amplifiers found all over FleaBay. Fantastic specifications, cheap price, and made in China. Now, to be completely fair, there is an awful lot of good stuff that comes out of China. Having an immediate family member that imports product directly from China, we have been exposed a bit and may have some interesting insights. If one wants to have a widget manufactured in China, one can have it manufactured to any tolerances and specs one wants. Meaning, you get what you are willing to pay for. China is capable of manufacturing widgets in world-class facilities to world-class specifications. China is also capable of slapping stuff together with the bare minimum of quality and even use contraband/fake parts all wrapped up in a shiny-looking package. That being said…We ordered a “High Power” amplifier and paid $169 for it.
While it is an impossible stretch to purchase a quality 6500wpc amplifier for this weight and price; could it actually be a very good 150wpc amp in actuality? The seller shipped it for "free" UPS Ground, and it weighs 35lbs packed so really this is a $169 amp. Is it worth it? Well... We like the case. It looks good enough for a rack. There are no air filters for the front intakes, but the case is solid. On the back panel there are two 24Vdc fans, some fake Speakon jacks, binding posts which feel pretty nice, 1/4" TRS and XLR jacks. Beyond that, the build quality is just crap.
The main amplifier PCB's are bent into place, and will probably crack in time. They're coated in some kind of sticky sealer, which will just get a nice fuzzy coating of dust within about an hour of use. It might be flux or something from the assembly process that wasn't cleaned? Who knows. The components weren't well placed; looks like the boards were just thrown together. Very doubtful there is any QC involved building these. There is a heavy duty three prong power cord, but the safety earth ground isn't connected to the chassis. EARTH GROUND IS NOT CONNECTED! It’s connected to the transformers internal screen, but that's it.
Obviously, there is no UL or CE certification. There's an empty stud for the ground connection, but it didn't get connected. All the high voltage AC and DC connections are insulated. The transformer is rated for 53V-0-53V and it has a 0-20V winding and a 15V-0-15V. No power ratings on the side, but I would guess 550VA. The DC rails measure +/-70Vdc. This is high for three pair of Toshiba output transistors, but normal compared to QSC, Behringer, etc…but make no mistake, this is not QSC quality.
The amp design is not a QSC copy, and has a discrete amp stage. The SIL08 package on the board is a UPC1237 IC making up the protection circuit. The amp has relays for disconnecting the speakers at turn on/off and for a fault, but they're small 5A components which would not have a chance in hell of protecting a speaker if the output shorted to one of the rail voltages. The contacts would weld shut and the speaker would die a horrible and smokey/sparky death, probably right before the over-sized 15A main fuse blew. There's no soft-start circuit for the large toroidal power transformer, so the inrush current at start up would blow a properly sized main fuse.
Conclusion: DUD! STAY AWAY .... Unless you really need a 2U case, 550VA transformer and a pair of heatsinks. The rest is pretty much junk.
