Author Topic: Behringer EP2500 Power amp schematic  (Read 4332 times)

AudioJohn

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Behringer EP2500 Power amp schematic
« on: December 19, 2006, 05:43:35 PM »
As many of you will know - access to any Behringer schematics are guarded better than the Crown Jewels in the Tower of London, so I was amazed to see this on another Web forum - and think it deserves to be widely seen and discussed.

http://www.eserviceinfo.com/downloadsm/27101/Behringer_EP-2500.html

No doubt some of us will be interested to compare this with another well known amplifier........


LazyOne

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Behringer EP2500 Power amp schematic
« Reply #1 on: December 19, 2006, 07:07:59 PM »
it probably is a sort of oem design and they are not that bad.
the only thing is. how is the supply? they cut back costs on that. the main design is good but the quality of the components isn't that great.
i am talking about. transformers,heatsinking,buffer capacitors!,etc....
i have a dap p2000 amp (it says 2*1025w rms @ 4ohm). i believe it doesn't differ that much from design. and the sound is acceptable. i only paid 450€ for that thing! i did it open and if you see that massive transformer+ buffer capacitors and massive cooling then it is quite a good price. you just have to look out what you do with it. treat it with some respect i mean.
i also have an inkel ma610 and ok thats also a simple design (altough completely discrete and class A/B). the difference is that it is build to last. it weights a lot more and can do 2 * 350 w rms continous i believe in 4 ohms or was it 300? (and i mean constant not burst or something)
the dap can do 1kw rms but not constant beceause it will overheat then.
i think the behringer would also overheat if you have a continous sine.
but then again we are talking about music and not sine waves!
for the price it isn't that bad.

walter

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Behringer EP2500 Power amp schematic
« Reply #2 on: December 20, 2006, 06:22:50 PM »
QSC, If I recall correctly, is who Behringer had design and build the EP1500 and EP2500. Now they are produced at Behringer City. I checked the link, but only got the one page. There is also a page with the other channel, and a page with the power supply, and the input jack section. But just try and get the Beefeater to give out that info.
   On that schematic, there is a Bias pot VR6. That pot can be adjusted so that there is 80mV across R106. If there is no bias across R106, and either one or both zener diodes D9,D12 are bad, upon replacing the zener diode, the amp works, What other components or voltages should be checked? I thought zener diodes were kind of fragile, especially these glass kind, and excessive heat can be the cause of failure.
Blown like a fuse

JohnRoberts

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Behringer EP2500 Power amp schematic
« Reply #3 on: December 20, 2006, 06:40:30 PM »
Quote from: "walter"
QSC, If I recall correctly, is who Behringer had design and build the EP1500 and EP2500.
 


And why would QSC help them design a product positioned to under cut their RMX series? More likely scenario is the design was reverse engineered the old fashioned way and process details leaked out of a Chinese factory back door that was already making RMXs for QSC.

If copying is the highest form of flattery, the flattery in this case extended to portions of the owner's manual too.

JR
John Roberts
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Tune it, or don't play it...

walter

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Behringer EP2500 Power amp schematic
« Reply #4 on: December 21, 2006, 01:06:01 PM »
Why indeed. I go to a local pizza pub, a sign in the window reads," Our competition sells for less, they know what their product is worth.".
Blown like a fuse

lydmann

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Behringer EP2500 Power amp schematic
« Reply #5 on: December 23, 2006, 07:13:01 AM »
Behringer,QSC and ALTO uses almost the same schematic,and exactly the same chassis except the front panel.

Must be made at the same factory in China somewhere.

Repair tip:
The pins on the driver transistors often break mecanically.

lydmann

JohnRoberts

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Behringer EP2500 Power amp schematic
« Reply #6 on: December 23, 2006, 10:54:58 AM »
Quote from: "lydmann"
Behringer,QSC and ALTO uses almost the same schematic,and exactly the same chassis except the front panel.

Must be made at the same factory in China somewhere.

Repair tip:
The pins on the driver transistors often break mecanically.

lydmann


I find it extremely unlikely that the chassis are the same exact part, run from the same hard tooling, despite what appears to be a very close copy. I am not familiar with ALTO, but the Behringer uses a smaller power transformer than the QSC and probably shaved a few other less obvious corners.

I suspect any reluctance to publish schematics may be more to conceal what isn't different than what is.

Regarding your repair tip, are you suggesting that all three brands exhibit the same exact failure vector, or is this more a general statement about plastic power devices?  

There seems to be much misinformation and poorly based assumptions floating around the web but QSC is a well respected, established power amp company with a several decades long track record of designing power amps. The Behringer amp was born fully grown so to speak.

It appears clear to me the RMX was a novel design created by QSC, derivative of their previous designs and they have no commercial reason to license or oem the amp to a competitor. Draw your own conclusions about how they now face a very similar competing model. IP law does not offer much protection for non patentable circuitry. In hindsight they could have filed a "design" patent (like on the coke bottle shape) for the amp's general shape and feature placement, but surely didn't anticipate such a close copy.

There have been successful defenses of trade dress (look and feel) but these are difficult to prove and expensive to pursue worldwide.

JR
John Roberts
http://circularscience.com
Tune it, or don't play it...


 

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