JBL MPX600
The JBL MPX600 is a professional two-channel power amplifier rated at 300 watts per side (600 watts RMS total), built in the USA and rack-mountable. It runs in Class AB and offers both XLR and TRS inputs. A used unit that surfaced on eBay — described as a takeout from a tour — sold with light surface scratches and a cosmetic rating of 7.5 out of 10, with the seller noting it "tested perfectly" and would make a solid studio or DJ amp.
Documentation on the MPX600 is thin. No production years, original retail price, frequency response, or distortion figures have surfaced in the available record. The only period-adjacent reference found appears in EQ Magazine (February 1995, p.102), which discusses a sound company's use of outboard gear and equalizers in a live setting — the MPX600's specific role there isn't detailed, but it places the model in the mid-1990s professional audio landscape.
One notable ambiguity: the eBay listing title calls this an "MPX Series" unit, while the item specifics list the series as "MG." Given the conflict, the series designation is best treated as unconfirmed. A forum post comparing the MPX600 against the larger MPX1200 ("other than the obvious power diff") suggests the two were considered alongside each other by buyers, though no conclusions from that discussion were captured.
Known specs, as far as the record goes:
- 300W × 2 (600W RMS total)
- Class AB
- XLR & TRS inputs
- Rack-mountable, rack ears included
- Made in USA
- Weight listed inconsistently: 65 lb vs. 49.5 lb package weight
For a working pro amp at a used asking price of $350, the MPX600 appears to have been a competent, no-frills workhorse — but beyond that, most of its story remains undocumented.
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